will it make 230 whp with those terrible flowing heads? will it even make it to 200 whp? nope. your 187 dyno was a farce which you admitted on www.realfierotech.com
For what it's worth, I did before-and-after dyno tests of the Trueleo headers. The "before" was ported stock manifolds with a Fiero Store Y-pipe (not as restrictive as stock). So I already had a decent exhaust setup going. But the Trueleo headers increased power and torque over that. Most of the performance improvement was above 4000 RPM. And there was no noticeable loss of torque in the lower RPM range.
Long story short, the Trueleo headers are good for an engine that likes to rev (and/or breathes really well). So that new camshaft should compliment the headers nicely.
[This message has been edited by Blacktree (edited 09-28-2015).]
Thanks, I have been using them for 8 years and they were on the engine that made 249 ft*lbs on a Mustang dyno, so I was well aware they didn't hurt my torque. I have the new motor built but discovered ignition issues. I've regapped the plugs and it feels better now. I hope to do some actual tuning soon. Torque feels good on the new motor (since the re-gap) now that it's a bit more broken in. Still under 500 miles on it with moly rings so it still smokes. Also, my muffler developed some holes so I couldn't get a good reading on the A/F ratio when trying to get a base tune. Need to get it patched up...it never ends it seems...
Along the way I've had to replace yet another 5x4.75" wheel bearing and a West Shore rear bump-steer control arm... ...it just never ends...
Hey Lou, try driving the car on long accel and decel. That will make the rings seat faster and better. My rings are usually seated in the 1st half hour of driving. And remember, don't use synthetic oil during break in.
Hey Lou, try driving the car on long accel and decel. That will make the rings seat faster and better. My rings are usually seated in the 1st half hour of driving. And remember, don't use synthetic oil during break in.
I have heard chrome-moly rings smoke for about 1200 miles...
My heads are almost done, they should be here in the next 2 weeks along with my short block. Then I have to put it together. Keep us informed on your progress! Good luck!
race on 10/10/2015 Made it to round 3, had the lead but my body rolled onto my wide 315R17/35 tire that sticks out so I lost control... Would have had an 18 second lap. I can really push the turns now with my tire upgrade. New cam makes peak torque at 3600 instead of 4000 of the stock 3400 roller cam and peak hp at 4700 instead of 4900...which is exactly what I needed to lower my drop clutch and only get pulled on 1.5 lengths off the launch against the AWD car. I was able to make up ground in turns 1+2 & 3 and take the lead in turn 4. Now the long wait until next May. The car that "beat" me is a perennial 2nd place finisher this year and missed 2nd place by 2 feet in this event.
stock rims weigh about 17.75 lbs with stock tires on and inflated, the wheel/tire package weighs 44.5 lbs each (15x7 215/60-R15). my tires (315/35-R17) weigh 33.4 lbs. My current wheels are 17x9.5 but heavier than these new 17x10 wheels. I won't know the weight difference until I have the rubber dismounted. So it looks like my new combo will only be about 11 lbs heavier than stock per wheel+tire.
Gonna be doing some surgery on the Trueleo intake.
A shame Trueleo didn't do their testing on ported heads. While these velocity stacks may help the stock 2.8, I think they have ended up being a restriction for my engine. Also, I'm finally removing the S neck that puts the throttle body infront of the decklid hinge so that I can run a proper cold air tube.
The rounded ends on the velocity stacks significantly improve airflow. If you cut them back, you'll need to replicate the rounded ends, or you will lose port flow. If you're not careful, you could actually end up with worse port flow than you started with.
The graphic below illustrates what I'm talking about.
But I think the fact that they sit in the tubes occupying space is a restriction overall. Remember, this is a 3.4 with a .040 over bore, not a 2.8. Also my heads flow much more than 150cfm... It probably does improve flow for a 2.8 but becomes a restriction for a 3.4... The 3.4 generates more vacuum. My peak HP is coming in about 300 rpm below two different cams' advertised peak. 4900 with the stock 3400 roller cam and 4600 with the 480/480 lift cam advertised at 4900. I'm using a 2.5" exhaust with 1 3/8" ports and primaries...so it's not the exhaust... This is the same motor that made 187rwhp/249 ft*lbs with the ported Fiero intake. I've made ~177/221 ft*lbs with this intake before putting on heavier wheels. My tune and timing is spot on so the only difference left is the intake. After cutting off the neck to have it the way I originally wanted (no S curve), multiple people looked inside and did not like the tubes. So time for some open-intake surgery...
[This message has been edited by lou_dias (edited 12-23-2016).]
IMO, what you really need are larger diameter tubes and a larger plenum. So basically, the whole upper intake needs to be replaced. Talk to La Fiera for some ideas.
IMO, what you really need are larger diameter tubes and a larger plenum. So basically, the whole upper intake needs to be replaced. Talk to La Fiera for some ideas.
My Formula daily driver also has a 3400 block but uses the stock ECM and Camaro 9.0 pistons... It's using a ported Fiero intake (the upper I made 187/249 with) that now has the DAWG-mod and it runs like a champ. I still haven't dyno-tested it or done any tuning to it. You're starting to make me want to switch back...now with the DAWG-mod it isn't crippled at 4200 rpm infront of a 3.4...
I'm hoping that the Trueleo tubes aren't a restriction and the the velocity stacks are just inserted in there lowering the inside diameter at the entrance of the tubes... I'm using a twin 42mm TB from a 91 V8 Firebird which is good for 400cfm...
I think I know what you're talking about. You can probably fix that by widening the plenum. Try to imagine slicing it down the middle, and prying the two halves apart. That should give your velocity stacks more breathing room. Make it wide enough, and your throttle body can bolt right onto it.
Cutting the trumpets flush will reduce the pressure drop in the plenum, but at the expense of increasing the pressure drop at the inlet of each runner.
Will the reduced pressure drop in the plenum make up for the loss in performance at the runner inlets?
If there are no significant gains to be had by opening up the plenum, it is silly to even think of chopping the trumpets.
To confirm that the plenum is indeed a bottleneck, I suggest you measure the pressure drop between runner #6 and runner #1. With a barb fitting at each end of the plenum, and a water-filled clear tube, you can have a passenger observe the pressure drop at WOT. 4 inches of water is approximately equal to 1 kPa.
"My Formula daily driver also has a 3400 block but uses the stock ECM and Camaro 9.0 pistons... It's using a ported Fiero intake (the upper I made 187/249 with) "
Lou, what you have to look is WHERE those 187 horses were made. Looking at your graph your HP peaked at 4300, then after that is coming down. That 4300rpm limit is where your intake system starts to choke. When I say system I mean TB, Intake and cam design. What I would do is get a bigger cam and make plenum bigger to move that 187 and even more, upper in the RPM range.
I have a upper plenum I can lend you and you can test it. It has plenty of plenum volume and nice runner length tor high hp and torque. It will stick out the decklid. But if you want to try it just pay shipping and I'll lend it to you. Its made out of a camaro intake.
[This message has been edited by La fiera (edited 02-14-2017).]
"My Formula daily driver also has a 3400 block but uses the stock ECM and Camaro 9.0 pistons... It's using a ported Fiero intake (the upper I made 187/249 with) "
Lou, what you have to look is WHERE those 187 horses were made. Looking at your graph your HP peaked at 4300, then after that is coming down. That 4300rpm limit is where your intake system starts to choke. When I say system I mean TB, Intake and cam design. What I would do is get a bigger cam and make plenum bigger to move that 187 and even more, upper in the RPM range.
I have a upper plenum I can lend you and you can test it. It has plenty of plenum volume and nice runner length tor high hp and torque. It will stick out the decklid. But if you want to try it just pay shipping and I'll lend it to you. Its made out of a camaro intake.
Yes - the neck was stock. Also, while the runners where ported, the gaskets were left stock and not cut to allow more air thru to match the larger ports. On page 7, I show a picture comparing the sizes of my ports to stock... I've since DAWG-modded it and that's on my Formula now with the 57mm bore Fiero TB. On my race car, I am installing a ported 2.8 F-body intake bored to 60mm mated to my twin 42mm TB.
I think you'd be better off using a Camaro 3.4 intake - it flows better but it is set up for DIS so doesn't use a distributor and needs modification at te rear to clear your distributor (or fitting DIS to your engine).
Someone must have done this before. My application is an in line engine so I didn't have to deal with the location of the stock throttle body.
Note that the throttle body had to be installed upside-down to put the bellcrank on the correct side.
This one is also upside down. Gee...2 bolts just like the Firebird intake... I should order a gasket to see how it would line up with the 2.8 gasket.... Don't like the height though and my twin 48mm does offer as much or more flow.
This one is also upside down. Gee...2 bolts just like the Firebird intake... I should order a gasket to see how it would line up with the 2.8 gasket.... Don't like the height though and my twin 48mm does offer as much or more flow.
Yes Lou but you are chocking the flow of the TPI TB with the black restrictor!
Originally posted by La fiera: Yes Lou but you are chocking the flow of the TPI TB with the black restrictor!
The adapter may not be choking the airflow as much as you think. Let's assume the opening in the intake manifold is 60mm diameter. That will give it cross-sectional area of about 28.3cm2. Now, let's assume the throttle plates are 48mm diameter, and the actuator rod is 6mm diameter. The throttle body would have a total cross-sectional area of about 30cm2. We're talking about a 6% difference in cross-sectional area. Yes, the air will speed up a little bit through the throttle neck. But as long as the walls are smooth in that area, the parasitic power drain should be negligible.
I see your point but the problem is that with the puny upper manifold and the black chocker the air will be very turbulent. He needs to keep the same diameter throughout and increase the plenum. The idea is to keep the plenum full by slowing the air in (big TB and big plenum) and then speed it up at the runners. If you empty the plenum before it can be filled up the engine will not hit 100kpa and its going to rev slower, it will also go into vacuum and that will affect power proportionally.
But if Lou's engine only revs to 45-4800 max, that set up should be ok. He'll have a heck of low to mid range curve!
I agree that the plenum on that intake is way too small. The intake ports are kinda small, too. But like you said, if he only revs it to 4500 RPM, then it may not make a big difference.
The plenum filling is a good point, though. And that's why I'm building a dual plenum intake. Each plenum will have twice as long to refill after each cylinder inhales.
I once had an idea for a dual-plenum intake using a TPI V8 throttle body. The idea was to make a big plenum with a divider wall in the middle, to split it in half. So each of the two plates in the TPI throttle body would be feeding a separate plenum. If someone were to do that to a 2.8 or 3.4 V6, I think they should use twin 52mm plates. The twin 48mm may not be large enough.
[This message has been edited by Blacktree (edited 06-01-2017).]
My adapter morphs to a 59mm round circle so it guides the air from the wide mouth to the perfect circle. I didn't use as high a polygon count in this print but I can acid-smoothen it with the vapor from nail-polish remover. I wanted to make sure it would last before going nuts. Again, I bored the FIREBIRD intake neck to 59+mm so no restriction there. The middle intake is the shortened one I used back in 2009 and the ports on the upper Firebird intake were widened to match along with the gaskets cut to match. My lower is the same lower, well-ported I've been using from the get-go.
Just waiting for my guy to remove the left Archie rocker panel to run the air filter with CAI to the throttle body, then I can take it to the dyno for tuning. He works on race cars for a lot of people that compete at Seekonk Speedway so I got to wait my turn... /sigh
The 480"/480" rollercam I'm using has an advertised peak of 4900 rpm. The TB and intake should flow plenty to 6000rpm. My next build will be a 3.5L version with the .510" cam. That engine will be high revving and will use longer V8 rods with shaved 3.5L pistons to reduce the dish-height to compensate for the longer rod and increase compression. I'll also be switching to the 1.76" intake valve and radius the opening appropriately. I'll probably machine down the valve stems as well.
At that point I'd probably switch to the LT1 throttle body...
[This message has been edited by lou_dias (edited 06-02-2017).]
