While I was fixing the broken F40 with a new one, I decided to fix the forged motor and reinstall it as well getting it all out of the way in one session. It was a lot of work and I spent all of my vacation time plus some extra getting it done.
Things I did differently and new upgrades: 745HN connecting rod bearings for the increased compression ratio and boost. .020 thicker Cometic head gaskets for ~ 11:1 compression & 89 octane use in low boost situations sensing the unrest in the Middle East & pending pump shock. Head studs. Clearanced oil squirters which were broken off by the pistons due to use of shorter 5.7" connecting rods. Moly piston rings. Steel fuel lines with fittings. Mallory adjustable fuel pressure regulator. Fuel pressure increased to ~55psi. Inline fuel pump added. 60mm wastegate, if I'd known it was as big as it is I would have gone for the 44mm. 50mm blow off valve.
Mild port and gasket match performed by Sappy on the 60 degree forum: Brand new 3900 heads, with pocket porting and gasket matching on the intake ports, fitted with custom Manley race series valves, PAC 1518 spring, Manley retainers, and new valve stem seals.
Manley Race series performance valves (intakes are NK-842; exhausts are XH-426) with chrome stems and hardened valve tips, swirl polished and fully machined.
I unwrapped the exhaust manifolds because the heat was taking its toll causing the flanges to draw inward and place a shearing force on the bolts. I simply cut the problem ends off and bolted the manifolds to an extra cylinder head and welded them back together.
The 60mm wastegate was placed up top for two reasons, it's adjustable from 4 psi which it is set at and it would have been to crouded down below where the smaller 35mm unit was placed. This makes adjusting the pressure very easy and quick without a spring replacement or having to jack the car up. It's much larger than what it needs to be so flow is not a problem. I didn't have access to dimensions before purchasing it and had no idea it would be as big as it is.
Wastegate and blow off valve.
Old next to the new.
I redesigned the exhaust also because the drone was getting to be more than I could stand. The mufflers look like typical glasspacks but they are not, they are baffled and contain no packing and are finished off with a set of chrome plated dual resonator tips. The drone is gone, the car is much quieter and sounds great.
Mock up on old drive train. 3" to dual 2.25 inlet, to dual 2" outlets with a planned wideopen cutout intended for the central joint at a later date if test results suggest it's needed.
Mufflers with ends moved and about to be welded together with a 4" diameter pipe.
Signal port installed for measuring exhaust back pressure against boost to determine status of efficiency and whether or not there's room to move down to a smaller turbine housing for quicker spool up.
Not trying to be a dick, but why are you spending this much on a forged motor and then putting ebay crap wastegate and BOV on it? You can get a decent turbonetics wastegate for around $200 and a decent blow off valve for around the same, a small investment consider the consequences if either failed. Otherwise, I really like this build. It's nice to see someone start from the ground up and set up a motor for boost.
Originally posted by ConvictedRedneck: Not trying to be a dick, but why are you spending this much on a forged motor and then putting ebay crap wastegate and BOV on it? You can get a decent turbonetics wastegate for around $200 and a decent blow off valve for around the same, a small investment consider the consequences if either failed. Otherwise, I really like this build. It's nice to see someone start from the ground up and set up a motor for boost.
I wouldn't mind a name brand wastegate but in this circumstance I'm not running a high performance level of boost to warrant the investment in parts that don't make the car faster or the engine stronger. The wastegate is actually custom made of stainless steel by the company it was purchased from in CA and the blow off valve looks better than and works just as good as the OE Saab blow off valve I had before.
The motor is solid and that's most important to me, I can easily replace the assessories. Despite not being a familiar name product, that wastegate is allowing me to limit the engine to 3 psi and then slowly increase boost 1 psi at a time in the seconds it takes me to open the decklid and turn the screw. There are tables in the code to limit boost in the event of a wastegate failure.
I don't put a lot of confidence in names anymore especially when the name adds as much to the price as the quality. I have a Mallory adjustable fuel pressure regulator that I read several reviews on after I purchased it that suggests it's not a good dependable part despite the name. It was too late for me to return it but I directed someone else to an aeromotive unit that had much, much better reviews regarding dependibility. There's also my Walbro fuel pump that's about as tough as glass.
As long as the part performs as expected it's worth the price paid. When the budget can sustain it, I prefer to buy American.
[This message has been edited by Joseph Upson (edited 02-17-2012).]
I wouldn't mind a name brand wastegate but in this circumstance I'm not running a high performance level of boost to warrant the investment in parts that don't make the car faster or the engine stronger. The wastegate is actually custom made of stainless steel by the company it was purchased from in CA and the blow off valve looks better than and works just as good as the OE Saab blow off valve I had before.
The motor is solid and that's most important to me, I can easily replace the assessories. Despite not being a familiar name product, that wastegate is allowing me to limit the engine to 3 psi and then slowly increase boost 1 psi at a time in the seconds it takes me to open the decklid and turn the screw. There are tables in the code to limit boost in the event of a wastegate failure.
I don't put a lot of confidence in names anymore especially when the name adds as much to the price as the quality. I have a Mallory adjustable fuel pressure regulator that I read several reviews on after I purchased it that suggests it's not a good dependable part despite the name. It was too late for me to return it but I directed someone else to an aeromotive unit that had much, much better reviews regarding dependibility. There's also my Walbro fuel pump that's about as tough as glass.
As long as the part performs as expected it's worth the price paid. When the budget can sustain it, I prefer to buy American.
somethings to remember though, if more units of the name brand sell than the off brand, even with a lower failure rate, you may have a larger quantity of failures, you really need to look at a ratio of sales:failures before jumping to any conclusions about a product.
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Originally posted by ericjon262: somethings to remember though, if more units of the name brand sell than the off brand, even with a lower failure rate, you may have a larger quantity of failures, you really need to look at a ratio of sales:failures before jumping to any conclusions about a product.
Not jumping to conclusions anymore than the assumed "Made in China, must be junk" attitude is. It's funny how U.S. manufactureres can shift jobs out of the U.S. to foreign countries saving millions in the process and the benefit of doing so not expressed in their prices. The consumer on the other hand accessess the same practice of financial maneuvering by buying a foreign made product directly at a cheaper price and he/she is cheap or some how automatically buying an inferior product. The business sector has done a good job of brain washing the consumer I'd say.
I've read more actual accounts of some of the name brand parts that I have performing poorly than I have seen "cheap China" parts meeting the description. In addition to the sales:failures ratio, one must also consider the learning curve. Case in point, Hyundai.
The engine is running fine so far and the transmission is still holding up. It appears the tendency to decrease spark plug gap on a boosted engine is another area that needs to be looked at along with the trend of reducing compression ratio with boost based on theory instead of need.
Initially the rebuilt motor was getting what appeared to be unusually good city mpg compared to the first build which had more to do with tune I thought. Not long after it appeared to decline a little to about what you'd expect for an engine with its displacement. This was on Bosch plat/copper plugs which I apparently regapped to something narrower.
I checked with NGK for a recommendation on heat range regarding my engine specs and the rep stated the stock 3900 plug is on the hot side and he recommended two heat ranges lower for my setup which would be the TR6 which it turns out is an application for the Turbo Grand Prix. I used the IX Irridium.
The Bosh plugs were gapped at about .028 following the trend. I figured since I didn't have a problem with stock plugs and the stock gap initially that I would install the plugs at their preset .040. So far there have been no problems and after driving it aggressively for a couple of days, I noticed I wasn't burning as much fuel as previously. It appears that seemingly small change in plug gap back to stock is good for what so far appears to be about 2-3 mpg.
Before, several boosted runs back to back would result in a little gas guzzling with the narrow gap, but not with the stock plug gap setting. My daily commute is right at 20 miles one way so the round trip fuel needle position noticeably changed until the new plugs went in.
Unless it's necessary due to symptoms, I wouldn't shrink the plug gap due to boost. Hopefully within the next two months i'll have dyno, or drag strip data to complete the thread.
Originally posted by Justinbart: So, you're judging how much gas you are using by the movement of the gas gauge needle from one year to the next?
Note that says "the rebuilt motor" which means this year. Sorry if I lost you but the comparison is between the Bosh plugs before regap (.040) and after earlier this year and the NGK plugs gapped at the OE .040 setting which indicate the drop in economy resulted from the regap to .028 as the economy now is back to what it was after the rebuild.
Obviously the difference is significant enough for me to notice right away that there is a change when the frequency at which I refuel over the same route is less or later and the fuel level at the end of the day is higher. That's over a few days comparison between the Bosch and new NGK plugs.
As for the previous year economy, I can remember back that far also and yes the economy is better over that span of time as well. No one puts fuel in it but me so I know.
Just a gentle reminder to keep this thread active until I can get some data from either a track which is too far away, or a dyno for a reasonable assessment, just say no to low compression boost. The motor moves so much air that the colder it gets outside the higher the boost climbs above 7 psi. It's pulling through 5000 rpm until I take my foot out of it. I'm more concerned for the transmission than I am the motor. It's doing fine on 93 octane and has hit 10 psi on 89 without knock retard. I don't deliberately press midgrade fuel like that, sometimes I forget that's what's in the tank on intended conservative driving days, I use it periodically because I generally don't have problems with knock retard with it.
This log was taken today in about 55 deg ambient temps.
This is a very interesting thread that I have only just finished reading! (Sorry, hadn't seen it before!)
I think that if I had alu heads, I might have gone higher static comp ratio on my 3800 ? In the end, I chickened out and kept it 8.5:1 !!
Keep up the good work !
PS I like your manifold repair. I had the same problem on an old Renault 5 Gordini Turbo. However, I just elongated the stud holes in the flanges and port matched the exhaust again. Should have cut and rewelded !!!
The lag looks horrifying if you are only making full boost for 1 RPM cell. It should be flat from 3000-6500?
It does pretty good, what you're seeing are the effects of on/off boost cycling and braking (in second and third gear likely), while cruising as well as the effecst of speed limits, none of that was from a standing start. The colder temps are causing boost to climb higher than the intended boost level also.
It'll hit about 7 psi by 3200 rpm from a standing start and before the slight drop in compression a little bit more than that. It doesn't hit nearly as hard off the line as it did at 11.5:1 (good for the tranny) and I contemplated dropping down from the .81 turbine housing to the .69 to recover it but so far the Turbo techs are suggesting it will choke the motor. For the kind of driving I do I really don't make good use of the upper rpm range not to mention there's no room for it on the street anyway.
I'm still shaking from nearly being nailed after cresting a hill on the hwy in the right lane with a cop sitting broadside on the shoulder about 100 yds out, so far above the 65 mph limit, I'm not going to say much about it other than I didn't even bother trying to brake. I guess he was aiming at the inside lane and thought the Celica he nabbed not far behind me had to be responsible due to location. Whatever the case, I don't want to be in that situation again. I just got a little carried away while airing it out to log boost level AFRs. This is why the boost peaks on the snapshots are shaped like an arrow, I have to get out of the throttle before speed gets too high so at best I can do a 2nd gear pull and a partial 3rd.
[This message has been edited by Joseph Upson (edited 12-23-2012).]
Did ben give you a before and after flow sheet on the heads? I know I'm not looking at them in my own hands, but it looks like the way the floor was ported would hurt flow once bolted to a LIM.
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Originally posted by ericjon262: Did ben give you a before and after flow sheet on the heads? I know I'm not looking at them in my own hands, but it looks like the way the floor was ported would hurt flow once bolted to a LIM.
There is a flowsheet somewhere on the 60 degree forum for his 3900 head port work. I don't believe he did much more than just smooth that area out a little for transitioning. I didn't buy them for the port work, they were part of a set of performance parts he was getting rid of and I got all of it at a great price considering the valves were burnt in my current heads at the time and I didn't want to crack open the good extra motor I have just for the heads. They work fine as far as I can tell.
ok, I haven't had a set of 3900 heads in my hands, so it's hard for me to see what I'm looking at, but looking at the pictures, it looks as though the floor was lowered, which from what I've seen of most of the other 3x00 motors. would probably reduce flow.
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ok, I haven't had a set of 3900 heads in my hands, so it's hard for me to see what I'm looking at, but looking at the pictures, it looks as though the floor was lowered, which from what I've seen of most of the other 3x00 motors. would probably reduce flow.
He just smoothed the entrance a little, I'm sure he's aware of the effect on air velocity enough to be careful about it. I learned the hard way a long time ago on a set of small block heads. Not sure how these heads compare to the specs he posted which are shown below.
[This message has been edited by Joseph Upson (edited 12-23-2012).]
You'll have to check with Ben to interpret that data as far as the reason behind the difference. It was posted some time ago and I don't know if the differences between those sheets are because of changes in how he measured them, or something else. I don't frequent that forum anymore and don't recall the conversation about the results in the thread. It's possible those results are for the heads I have on the motor but he never said anything to suggest that when I purchased them.
ben got out of the 3900 stuff because the heads are really easy to mess up, he may have just been clearancing out all his 3900 stock, improved or not...
ben got out of the 3900 stuff because the heads are really easy to mess up, he may have just been clearancing out all his 3900 stock, improved or not...
I think it was more than that, the heads are fine stock, he seemed to have a bitter taste regarding the motor a little stronger than simply not being able to improve on their flow much would suggest from what I gathered. I recall him rounding up some core pieces to experiment on, certainly wouldn't be wise to practice on a brand new set. The VVT motors don't lend themselves very easily to modifications, that would be a good reason along with the small number that have been swapped plus the low demand for related performance parts as a result. I would like to look into a larger exh valve along with opening up the port, I believe a turbo motor would benefit quite a bit from that.
The 3900 head has a lower floor to start with than other 3x00 heads, about .200" if memory serves. Looks to me like he just ran the sanding roll inside the port to clean it.
You'll have to check with Ben to interpret that data as far as the reason behind the difference.
Interpret? I can do math thanks.
its all right there, black and white, clear as crystal.
quote
I would like to look into a larger exh valve along with opening up the port, I believe a turbo motor would benefit quite a bit from that.
Why would you even think this? The exhaust side is where you want a small stout valve that will not give you any floating issues. Exhaust pressure is double that of intake pressure on a turbo car so you can flow twice as much through the same area.... Intake side is where you gain power, getting air out is never easy.
[This message has been edited by darkhorizon (edited 12-24-2012).]
Originally posted by darkhorizon: Interpret? I can do math thanks.
its all right there, black and white, clear as crystal.
Why would you even think this? The exhaust side is where you want a small stout valve that will not give you any floating issues. Exhaust pressure is double that of intake pressure on a turbo car so you can flow twice as much through the same area.... Intake side is where you gain power, getting air out is never easy.
I didn't think the numbers would "tax" you too awful much, but without the context unless you communicated with him or saw the thread regarding it, you're making an assumption that maybe incorrect. The number differences may be due to his method of measure during the initial tests, which I recall some debate about, not necessarily a before and after comparison. I don't know for sure aside from the little I recall about it due to the time. I just don't recall it being a before and after but more so a correction.
It's been some years since I saw the show on it, but I recall the larger exhaust valve for performance improvement in a turbo application as being one Duttweiler used. You would also have to assume the stock valve size from the factory is perfect already to suggest there would be no benefit and that's unlikely, not to mention displacement has been increased. If the LS1 can benefit from a larger valve then it would stand to reason that it offers some improvement along with working the port since both engines have the same bore. My understanding is that exh valves are smaller because once opened much of the airflow is passive unlike the intake side and due to combustion pressures it's easier to open a smaller diameter valve against it.
Since air is being forced in as opposed to pulled in the flow dynamics are a little different, there's also the issue of the substantial increase in volume of the combusted gasses. It's a stock valve in a modified application that makes perfectly good sense when you consider the needed increase in exhaust system flow.
I figure within reasonable limits it'll work about as well as high compression with boost. It's not something I'll be doing anytime soon but I'll certainly look into it.
[This message has been edited by Joseph Upson (edited 12-24-2012).]
Originally posted by darkhorizon: Why would you even think this? The exhaust side is where you want a small stout valve that will not give you any floating issues. Exhaust pressure is double that of intake pressure on a turbo car so you can flow twice as much through the same area.... Intake side is where you gain power, getting air out is never easy.
Here is a link to some definitive flow numbers over various 3X00 engines, intakes and a couple of throttlebodies performed by Sappy. I also found a comment of his that will probably also bear out in the data below that states the 3500 and the 3900 have virtually the same exhaust port despite the different exhaust valve size so it stands to reason a larger exh valve and port work in the 3.9 may provide appreciable flow improvement with the turbo. Perhaps swapping from the variable intake to the single stage will offer a benefit also.
And no you dont magically gain power by adding a larger exhaust valve in a turbo motor.
What a insightful analysis.
Power to be gained by larger valve is most definitely not magical.
What it will do is create a larger curtain area, especially important at lower lifts where flow across a poppet valve is much lower, allowing more gasses to escape sooner in the exhaust stroke. Does this effect power? It effects the ability to achieve an higher thermal effiency of the combustion cycle, by allowing more complete evacuation of post combustion gasses. This lowers the cylinder pressure and mean temperature during the induction cycle, allowing the engine to achieve an higher isentropic effiency, and netting a higher VE.
It is not uncommon for many Turbocharged IC engines to have a higher exhuast manifold pressure that inlet manifold pressure, due to suboptimal runner design, turbine selection, and nonexistant resonance tuning combined with operating range limitations. A well designed system should have cylinder pressures that far exceed the exhuast systems prior to the turbo, Flow across a valve is a dependant on orifice size and pressure differential.
DH, read a book, you might learn something. If everything you say was true, we might as well all run Flatheads with Holset's strapped on top.
Power to be gained by larger valve is most definitely not magical.
What it will do is create a larger curtain area, especially important at lower lifts where flow across a poppet valve is much lower, allowing more gasses to escape sooner in the exhaust stroke. Does this effect power? It effects the ability to achieve an higher thermal effiency of the combustion cycle, by allowing more complete evacuation of post combustion gasses. This lowers the cylinder pressure and mean temperature during the induction cycle, allowing the engine to achieve an higher isentropic effiency, and netting a higher VE.
It is not uncommon for many Turbocharged IC engines to have a higher exhuast manifold pressure that inlet manifold pressure, due to suboptimal runner design, turbine selection, and nonexistant resonance tuning combined with operating range limitations. A well designed system should have cylinder pressures that far exceed the exhuast systems prior to the turbo, Flow across a valve is a dependant on orifice size and pressure differential.
DH, read a book, you might learn something. If everything you say was true, we might as well all run Flatheads with Holset's strapped on top.
Precisely my thinking, at some point with cylinder heads flowing far more exhaust gass than the engine they were designed for produces, there is a possibility to come near, reach, or exceed their capacity to flow the volume effectively, a circumstance that can benefit from modification. I used the LS engine as an example of an engine with a larger exhaust valve because the heads for the 3.9 were patterned after them according to GM along with the stroke increase modification I had performed. I'm just aiming for as much efficiency in the operating range as can reasonably be expected.
I made it home to redo the wiring harness and wound up fixing everything that needed fixing, as a result the car is still being put back together after 2 weeks. First on the list next to the harness was the jumpy fuel gauge and the noisy, sensitive Walbro pump. Several years ago I purchased a set of shorty 30 lb/hr injectors along with the rail and pump module from a new GM 8100 V8 truck that was converted to propane. Since it runs a rail pressure in the 50s and my setup runs 40 it should be more than sufficient considering it supports the torque of an 8.1 litre V8 and it's bigger than the Walbro and should also be quieter.
While underneath the car I also found two cracks in the cradle near the rear transmission mount pad. Since I'm using interlocking poly mounts I took a torque strut installation for granted so I'll be adding one of those to offset the additional stress that the mount pad is being subjected to unabated.
On second thought, that one is probably from jacking the car up at that point center of the cradle.
[This message has been edited by Joseph Upson (edited 03-23-2013).]
Finally made a trip to the dyno. It seems some changes I made over the past month during the temporary switch back to code59 and then back to 8F after 59 ran very inconsistently to down right unreasonable compared to the first time I used, are going to take some more undoing. When I left off 8F, it was running pretty decent except for a closed loop intermittent idle hunt that showed up just before the code switch and remained after the switch back. I'm suspecting the TPS sensor as tightening the exhaust manifold bolts one of which was very loose did not resolve the idle hunt and I noticed the TPS was a bit slow to change when I adjusted the throttle open a little more.
As for the Dyno experience, it's down right scary to watch and hear the motor wind up the way it did and I assumed the guys conducting the tests would guide and advise me along the lines of the common sense stuff. When I was asked about the rpm range, I gave a safe limit of about 6300 rpm stating it would do it. I assumed the guy would only take it as far as it was actually pulling short of the limit I gave.
The dyno sheet shows otherwise as apparently the power was breaking up not far beyond 4000 rpm and I was told the motor felt like something was causing it to fall over at a certain point, so with that said there was no cause to run it much further beyond that point, especially not 6K.
The motor was run in closedloop so when ever he shut it down between runs the cold/hot start timer kicked in (I didn't realize this until just before the last pull and had him wait a couple minutes) and the commanded fuel AFR was roaming as a result going into the test, not sure if it had any effect up top though.
SUMMARY of events:
The variable intake valve makes a difference: First pull with the valve closed represented by the blue trace; HP 307, TQ 315 AFR 11.0, 13.7 psi Second pull with the valve open represented by the green trace: HP 295, TQ 322 AFR 11.3, 13.6 psi Third pull with the valve closed represented by the red trace: HP 304, TQ 311 AFR 10.48, 13.9 psi
The first two pulls occurred within 5 min, the third pull had about an 8 min break from the 2nd while I added ice to cool the water down thinking it was going to get chilled but the 2 warm gallons melted the remaining ice in the time it took me to step down and turn my back. It brought the inlet temps down to ambient 98 deg where I was thinking I might see 50 and possibly blowout problems from water condensation forming in the intercooler.
The tech was right up to a point, the last pull was well on its way to being the best until it either fell over from spark die out, or it was too rich. Here is why, I added more fuel to the boost multiplier (2 clicks) from about 130 kpa through to the top. Normally the motor runs about 12-12.5 AFR until about 7 psi where it dips down into the 11s and by 10 psi is bouncing off 10.9. Since the upper level was already very rich I incidentally made it worse or a combination of ignition and rich condition caused it to break up even sooner. The charge pipe blew off the turbo but I believe that occurred at throttle closing suggesting the spring in the blowoff valve is too strong and therefore not opening soon enough to relieve pressure.
I know the car has a lot more in it, because I've run it before without breakup and if it has always been at this power level, pushing near 500 hp in it is crazy as it is already much too fast for the street. I added the thermostat causing it to run much hotter ~200 + deg and that doesn't help the results, not to mention the timing retard that kicks in at those temps (no spark knock though). It has pulled well beyond 5000 rpm so it should be closer to 400 hp/tq when all is in order. The dyno tech said the dynojet is on the conservative side but didn't translate that into numbers.
I'm not happy and I'm not mad because I know the results are problem limited. I am hot here in FL so it will be a while before I work on the kinks and go back for another test.
Hopefully I'll have the video up by tomorrow so you can see the pulls and note the signs of blowout and overly rich condition, and maybe I'll have that email with hopefully a better dyno printout.
Hope this helps someone and hope I stop saying hope so much.
[This message has been edited by Joseph Upson (edited 08-19-2013).]
Forgot to mention, the plugs are new and gapped at .025, since my compression is so high, i'll probably need to take it down to .015 for the next dyno visit. The test was performed with pump 93 and around 10 psi methanol is injected (I think, haven't confirmed the light is coming on as proof in a while now) although amazingly it is not necessary per testing without it up to at least 13 psi before. That's another area that has to be checked. It has also hit 18 psi within the past couple months so looks like I'll need to go back and find that tune as today with the same adjustments it didn't break 14 psi so something is definitely up.
Forgot to mention the guy did not fully apply pedal as the first two pulls showed 80% TPS and the last 86% in the log. This is info I'm finding out after the fact.
[This message has been edited by Joseph Upson (edited 08-19-2013).]
The motor sounds like it's skipping at idle but it's not, that's the sound often complained about after a large injector swap and adjusting closed loop idle to run at 14.7:1 AFR along with a BLM at 128. It doesn't do it in openloop or with an AFR around 13, however, the car feels like it just runs better in closed loop. None the less the sound is just as annoying in the car as it is outside so that will be changing as well.
There was no knock retard recorded at the break up points, only some on high rpm decel at very high vacuum.
[This message has been edited by Joseph Upson (edited 08-19-2013).]
I compared the tracing from the first pull to a test I did on the hwy after some changes and there are significant differences in peak boost and the slope which topped out just above 18 psi and also held as well as reached 14 psi at least 2 seconds faster on the road than 13 on the dyno. The boost onset was so fast I had to back out of the throttle which was already less than what was used on the dyno at just over 60% vs 80.
For some reason on the dyno boost hit peak and then dropped about 1.5 psi before he released the throttle. I have not made any adjustments to the wastegate. Perhaps the dyno was doing something strange.
There may be a problem with hopefully my laptop instead of the ecm. Recently a couple of high boost runs have locked the log in error mode where the normally blue log signal turned red and the logging freezes.
I also noticed while screen capturing the snap shots that the seconds at the bottom of the monitor screen are duplicated. Is this a TunerP glitch or something else.
Clearly the lean is mean cliche does not apply to my application as richening the low boost range to bring the AFR into the 11s made a big difference, even when compared to the other pulls where the initial enrichment at boost onset was in the 12s. All of the dyno pulls show the same sag in the boost curve climb and that's apparently what the operator was describing to me as something holding it back and then releasing it.
The fueling correction with a narrower spark gap should yield a sizable improvement.
[This message has been edited by Joseph Upson (edited 08-21-2013).]
Haven't had anymore trouble with spark blowout. So that it's no longer hearsay I did a quick video of the boost gauge as proof of the 15 psi boost level with my compression ratio. I have run as high as 15 psi without water injection although I have it coming on at about 10 psi. I forgot to open the electric exhaust cutout so initially boost was limited to 10 psi.
I'm about to do some New Years upgrades and repairs since the spark blowout problem has been resolved.
Smaller 44 mm wastegate to replace the monstrous 60 mm which I purchased without knowing the dimensions of otherwise I would not have. The difference in install height will be about 4" plus a trimmer waste and new location to allow room for the long overdue dog bone to the give the interlocking poly mounts a break.
Somethings gotta give:
Studs for the exhaust manifolds to resolve the bolt loosening problem once and for all.
And some more go fast quicker with a .68 turbine housing to replace the .81 to bring boost on starting at about 2000 rpm instead of 2400 rpm due to the relatively large turbo being a little to conservative off the line. Initially when the engine was at 11.5:1 compression along with a fully advanced cam the bottom end performance was brutish, but once it was dropped to 11:1 and a cam with a little more duration was degreed in a lot of the bottom end torque was shifted upwards.
The front exhaust manifold appears to have held its shape since the heat wrap was removed due to warping and flaking. It is fairly flush against the gasket.
[This message has been edited by Joseph Upson (edited 01-01-2014).]
I got the exhaust manifold studs installed and found that they were desperately needed. Below is a picture of what I found while removing the bolts along with at least two others that were loose on the same manifold. I used medium threadlock on install of the studs.
The new turbine housing comparison, .81 down to a more practical street size .68.
I spray water/meth preturbo also and so far there is no blade erosion present. The blades are pretty thick and much more sturdy than a smaller turbo say a T3 for instance. Upon inspection of the nozzle which was a McMaster Carr industrial get up not one of my Snow Nozzles, I found that it had clogged and this had more to do with the fact that I left it in place and unused for quite a while although it was sealed. When I tested it I found a low pressure stream of water. Fortunately the nozzle is very close to the compressor wheel nut which pulls the fluid in toward the center making it difficult for droplets to reach the higher speed outer diameter of the blades at high rpm.
The nozzzle I have in place now is one of my extra snow nozzles but I'm not sure which size other than that it is not the largest but definitely more than 1 gal/hr.
The wastegate was worth the effort, I gained a huge space savings not to mention access to the rear plugs again without having to remove the coil/module assembly. It holds boost just above its 15 psi rating.
So far the results have been quite positive, the turbo spools up quicker as can be seen in comparison to the snapshot in an earlier thread. The turbo can be heard a bit easier also. The snapshot doesn't show it because I haven't run the car as hard as it will go briefly from a standing start to maximize spool up quickness but it is easily felt. I'm still adjusting the tune to accommodate the earlier boost onset by working the AFR down into the proper enrichment range. I have the dump pipe and torque strut left to finish it.
