Going over my list for my swap this winter and a thread here got me thinking of going very mild boost 4-7 psi. But honestly I have no idea where to start. I have the "High Performance Fieros" book that covers Turbo install but doesn't cover much details like setting the boost level and other issues outside of installing. Does anyone have any good links for someone getting started into turbo retrofitting? Choosing parts and how to adjust things. what are the disadvantages of putting the turbo far away from the exhaust manifolds? Why don't you see anyone with a turbo way down just before the CAT where there's lots more room? What about a small low pressure turbo without a intercooler?

I know this forum is full of turbo fiero guys that have successfully boosted their car from 2.8 to 3.4 and on up. And it's full of people that are really interested in the ins and outs.

Thanks all!

Here is a good article to read... http://www.westcoastfiero.c...o_systems/turbo.html

Also alot of stuff at Turbo City is pretty informative..

As far as members, Will, Dennis LaGrua, PBJ, and FieroX, to just name a few, are very informative on the subject.

------------------
Former West Coast Fiero Employee
www.WestCoastFiero.com


Eric Nelson
Internet Sales Manager
Power Ford Valencia
nelsone@autonation.com

you can put a turbocharger any where you have room for it .the disadvantage is that you need an electric scavenger pump to get the oil pumped back to the oil pan .if you dont have a good gravity drop straight down in to the oil pan ,oil will leak past the seals and it will smoke badly .most stock turbos are set up for 6-8 psi boost .i dont know where you could find one with only 4 psi boost ,but you would still need bigger injectors to prevent detonation .check out rb racing website for lots of general info relating to turbos .

I have the "high Performance Fiero" book, it has been sitting in a box since i bought it...

If you want to learn about turbos the ONLY thing you need is the book below!!!
I have done a few turbo setups pretty much just based on what that book taught me. Of course i also scanned th enet looking at other people builds to get ideas. From my experience pretty much any engien can handle 10PSI without conflict... Personaly i have boosted stock engien up to around 15PSI without problems. However those engien that went over 10PSI where newer engines with better tuning capabilities and all around better design for a turbo (16V, DOHC etc...). I actualy boosted my stock DOHC in my neon at about 12PSI daily and when i hit the track i would bump it up to 16 or so. Ran it like that for about a year with no problems before selling it.
Pretty much just took all the stuf fi needed off of a 1G DSM (B16G turbo, SMIC, 450cc injectors, Manual Boost Controller) all i had besides the "hardware" was an SAFCII. I REALLY embarrassed some people in that car!

Maximum Boost written by Corky Bell
http://www.amazon.com/Maxim...rmance/dp/0837601606

[This message has been edited by SLOWnSTEADY (edited 08-15-2007).]

I started my turbo quest about 4 years ago with nothing but desire. There are tons of books that cover theory very well but a step 1, step 2 book does not exist. It all depends on money, time, and space with money being the most important. For a DIY turbo you will need a welder. At least a gas type Mig welder. A Tig is nice to have also but not required. If you want to mildly boost a stock engine the simplest solution is buying a junkyard T3 with built-in wastegate ($75-$100), rebuild it ($90), weld up a turbo manifold ($100-$200), add larger injectors ($75 used), add '85 ECM with Darth chip ($100-$200), 2 bar MAP ($50), Blow off valve ($60-$150). That gets you the big parts. Add various intake/exhaust tubing, clamps, hoses, etc which quickly adds up. This is for the stock 2.8. If you have the 3.4L you can switch to the 7730 and use the DIS and a turbo chip for the 3.1L turbo cars.

As wftb said, turbo's are usually mounted above the oil pan for oil drain back. And I am starting with no intercooler and mild boost. I do plan on upgrading later to a T3/T4 Hybrid and using an intercooler. (much later like when I toast the engine...)

I do not have any Fiero turbo links since Dennis took his pages down. I can give you a recipe for a system but you would have to put it together for your taste.

Now that is what I am after. I have ordered a few books from amazon.com (gotta loved the used section!) There are very few websites out there with useful info, most of it is "look at my turbo I installed" with zero real info. If we can make this thread a good place for the newbie to Forced Induction-turbo style it may help some people make the decision to either try it themselves if they have the tools, buy a kit from design 1 or give up and swap engines.

I do have a very nice gas-mig welder, my Geo's exaust system is almost 98% mig welds and 2% exaust pipe by now. and have friends and family that have almost everything else.

How about using secondary controllers like some of the honda guys use? can you get away with those in the Fiero to save effort or is it still the best way to swap out the ecm to an 85 and start there for stock?

[This message has been edited by timgray (edited 08-16-2007).]

I'm not sure of using a piggy back fuel controller as the ones I looked at were expensive so that is as far as I went. At first I was going with the '85 ECM because of the knock sensor input. Then after reading Darth's 7730 swap I went that route. There are so many ways to tackle more fuel delivery it makes your head spin. I would hazard a guess the easiest is the '85 ECM w/knock sensor, then the 7730 ECM (knock sensor too), then the typhoon/syclone ECM, then aftermarket type controllers like F.A.S.T.. The odd man out is the DIY controller Megasquirt. It is very versatile, somewhat inexpensive, but you will be tuning on your own. More and more people are using it though so help and support are getting better.

My decision making was two-fold. Where to mount the turbo/exhaust and how to control ignition/fuel delivery. Mounting for me was over the trans as there is plenty of room over the auto trans. The manual trans have shifter cable issues to deal with. I can't speak to those.

the main thing you are trying to control is engine destroying detonation .on my ecotec swap , i am still using the unmodified ECM .the bigger injectors and my electronically controlled Snow water meth injection take care of the problem . the only drawback is hot starting ,the computer doesnt compensate for the bigger injectors when you start up so you have to avoid flooding.that is not a problem with the 2.8 because it has a seperate cold start injector .sounds like the 85 ECM with the knock sensor is the way to go .
a blow off or recirc valve is a must .without it you will destroy you compressor blades in short order . cheapest is the bosche plastic one .64 bucks from summit racing .

quote Originally posted by Hudini: This is a good idea. I wish something like this existed for me when I started. I'm wondering where to begin? With forced induction basics like adding more air requires more fuel or just start with the how to? Where do you want to start?

FINALLY! I have been asking these same questions for a while now without result. You guys are really coming thru.
Maybe a place to start would be "How to select the right turbo for your application". All I hear is T3..wah wah...T4...wah wah... T3/T4 wah wah.....kind of like a "Charlie Brown" school teacher. I have access to Garrett (Honeywell employee, We own them) and they have different wording like GT3071....GT3892...etc. I know it would be better for water and oil cooled, but how to pick the right size.....something about compressor map?

Here are some pics of the first turbo installation that we did. This was about 7 years ago.




The turbo is a Garrett T-3 from a mid 80's Ford Thunderbird 2.3L. I bought it for $50 at a junkyard and rebuilt it with a $80 kit from Limit Engineering (kits also available on eBay). The T-3 turbo mounting flange came from Limit and the crossover pipe is formed from six pcs of mandrel bent 2" OD SS tubing mig welded together. Your crossover pipe MUST not be larger that 2" or you will slow the exhaust flow and get very poor bottom end performance. A mounting bracket holds the turbo over the trans housing and is just a couple of pieces of L channel steel welded together. It is suspended on a spring mount as to allow movement so the crossover doesn't snap.
A piece of corrugated aluminum flex air pipe mates the turbo inlet to the stock air filter housing.
Originally we had an MSD BTM but with boosting you need both fuel and spark control. We solved this by adding a 2 BAR MAP sensor and a chip program that I developed. Later on we added a blow off valve that was purchased on eBay and later still we upgraded the turbo to a T4/T3 hybrid (using the Grand National Compressor wheel) , and put it on a high performance built 3.4L The original setup on the 2.8L was done for around $750 but with 50 hours of work planning and fabricating.. The final iteration with Sprint headers, a knock sensor based on the 85V6 ECM) and turbo modifications added another $700 to the price. If you turbo your 2.8L make sure that your engine is functioning up to specifications before you try boosting. You can adjust the boost by adding an adjustable rod end to the waste gate so on a used good engine (w 50K miles or less) just keep the boost to 7-8 psi max and you'll have about 200HP.

[This message has been edited by Dennis LaGrua (edited 08-16-2007).]

For a low boost application larger injectors may be premature. There are calculators all over the net to help determine fuel requirement for boost level and engine size. Low boost is the operative word in your quest and in my experience, you should be able to manage 4-5 psi easily with some minor changes to the stock programming, particularly a few degrees retard on wideopen throttle, better yet if you use 92 octane you may not need to retard the timing at all with 4-5 psi because each octane point above 87 octane which the engine runs fine on will buy you detonation resistance for about 1 psi of boost, plus the cushion already programmed into the chip which should already allow you to get away with about 2 psi and no adjustments.

You want your injectors to run right up near their max safe zone for your boost level to reduce tuning issues like running too rich at idle. The larger the injectors the more tuning necessary to dial them in so there is no need to have more injector than you actually need. The stock injectors will automatically function at a higher flow rate when the manifold is pressurized because of its effect on the pressure regulator, the same principle behind having a vacuum line feed to it to lower fuel pressure at idle due to the vacuum on the diaphragm so wideopen throttle fuel pressure should increase by your boost level ~45 + 5psi=50 psi at the regulator.

The engine I'm about to swap out has been beat on for about 5 years at 7psi and it has never seen the use of proper tuning equipment unfortunately, but amazingly it stood up to the abuse sometimes seeing well over 6k rpm. If you avoid the bad habit of ignoring the benefit of a wideband O2 datalogger you can get the most out of a low boost build especially if you can increase intake flow.

Maximum Boost is a must have, the proper understanding is more important than anyones step by step install on their vehicle because once you understand the "why" behind it all you'll find that the vehicle about to be turbocharged is irrelevant because you'll know in advance what the requirements are.

[This message has been edited by Joseph Upson (edited 08-16-2007).]

quote Originally posted by rjblaze: FINALLY! I have been asking these same questions for a while now without result. You guys are really coming thru. Maybe a place to start would be "How to select the right turbo for your application". All I hear is T3..wah wah...T4...wah wah... T3/T4 wah wah.....kind of like a "Charlie Brown" school teacher. I have access to Garrett (Honeywell employee, We own them) and they have different wording like GT3071....GT3892...etc. I know it would be better for water and oil cooled, but how to pick the right size.....something about compressor map?

You can easily call a turbo maker like Turbonetics to get their recommendation for a turbo. Give them all your information and they will tell you which turbo (their turbo of course) is best. These turbos are very expensive though. The reason most use the T3 or T3/T4 Hybrid is price, support, and availability. I don't think Garrett even makes the T3 or T4 anymore. BTW the T3/T4 Hybrid is the T3 turbine section mated to the (bigger, more efficient) T4 compressor section.

Like Dennis, I got a junkyard T3 and rebuilt it. I know it is a bit small for the 3.4L engine simply because it came off a 2.3L engine. It should spool fast and make max boost quick but will run out of boost at the higher RPMs. A better choice is the T3/T4 Hybrid because it has a bigger compressor that will make more boost at higher RPMs.

Like Joseph said, get the book Maximum Boost to learn the ins and outs of theory. Then you will understand why you need a Blow Off Valve and a Wastegate, why you want to retard timing under boost and add more fuel to control detonation. Then call a turbo shop like Turbonetics to see what they recommend. Ball bearing, water cooled, 60 trim, ad nauseum. When your eyes roll back in your head from the price, then go get a junkyard T3. If you can stand the price, then the rest is easy.

I am actually lucky that the actual turbo won't cost me much at all due to the Honeywell/Garrett (I am an employee and already talked to someone about getting one for a ridiculuosly low price).

I have just ordered "the book" to help me understand what I want.

Do any of these:
http://www.turbobygarrett.c...chargers.html#medium

Look good for a 3400 roller block, worked Camaro head, 7.66:1 (Too low?) compression motor? I was hoping not to have to change the pistons on my extremely low mileage (1500) 3400 I got. I will be using all the associated fiero intake (Modified), etc. I was thinking the GT2560R-9 or the GT2871-9.

You guys are a fountain of knowledge. Thanks for the help.

timgray: thanks for getting this started!!!!!!!!

[This message has been edited by rjblaze (edited 08-16-2007).]

quote Originally posted by rjblaze: I am actually lucky that the actual turbo won't cost me much at all due to the Honeywell/Garrett (I am an employee and already talked to someone about getting one for a ridiculuosly low price). I have just ordered "the book" to help me understand what I want. Do any of these: http://www.turbobygarrett.c...chargers.html#medium Look good for a 3400 roller block, worked Camaro head, 7.66:1 (Too low?) compression motor? I was hoping not to have to change the pistons on my extremely low mileage (1500) 3400 I got. I will be using all the associated fiero intake (Modified), etc. I was thinking the GT2560R-9 or the GT2871-9. You guys are a fountain of knowledge. Thanks for the help. timgray: thanks for getting this started!!!!!!!!

As far as the benefits of your association, see what you can do to get turbo members a good price for upgrades, as for your 3400 the worse thing you can do is take the aluminum heads off of it and put the Fiero intake on it. That engine is turning easy 300/300 power levels on 10 psi in stock form. Low compression is a thing of the past that carried over from pre fuel injection and then fuel injection without the ability to reprogram. Those days are gone. You should run the highest compression that your boost level will allow, that will keep your efficiency up to maintain good gas mileage and off the line response. Again do not downgrade your engine and then boost it back up with the turbo. The 3400s that have posted over 300 hp are all running at least stock 9.5:1 compression, further more it is a perfect opportunity to start with the Turbo Grand Prix code and a 730 ECM, you will only need to tweak the tune since you will already be close.

I made the mistake of installing the Fiero intake on a 3100 that was like new, and if that wasn't insult enough I was in a hurry and put the low performance iron heads I had sitting around on it. At about 8:1 compression it still ran impressive, how much better had I left it stock. You can have your camshaft reground for about $90 to get more performance also. Leave the aluminum heads on it whatever you do.

We should be talking to you about which turbo to get! Lol, you have access to the people who design them.

Seriously, call Turbonetics and give them your engine info. They have a program that will spit out the best one for your needs. Since selling turbos is a very profitable business, there are not many open source turbo calculators. I did see one from a company in Australia. It lists the GT25 with the .82 a/r turbine housing as a match. Of course, it may list this turbo for every engine on the planet because they have tons of them in stock......

http://www.turbofast.com.au/TFmatch.html

mmmm turbos...

Even more great info! A reccomendation for where to start on a 2.8 or a 3.4 is best for a dummies kind of thread. I am assuming that the higher the boost the more complex everything gets.

Ok so locating the turbo is not that big of a deal, you just want to get the oil in and out. Would upgrading to a high volume Oil pump be a really good idea then? Where do you recommend tapping for oil to feed the turbo? is popping it back into the oil pan side the best solution?

Intakes for the turbo. Use the stock airbox or ditch it? How about exaust feed? Did you modify a stock crossover pipe or build your own? adapter plate tips? What mistakes did you make that someone else could easily fall into on the intake side and the exaust side? What kind of intake pipe did you use? aluminum with silicone joints? all steel welded? why?

I have lots more questions, I also have about 3 turbo books and a ECM tuning book for Forced induction coming from amazon. What would be really great is that out of this thread someone would do a turbo for their 2.8 and completely document it with every tiny detail and post it to compliment it. I would loveto see turbos be as well covered here as the 3.4 swap and 3800sc swap have been.

From what I can tell the T3 from the old thunderbird is really easy to get, there are 5 of them on ebay now and a local junkyard has several. Would a T3 be a great choice for a low boost for the 2.8 and 3.4? what are the disadvantages of having too small of a turbo?

Just for curiosity, 200hp from 6-7 psi boost on a 2.8, does that mean on a 3.4 it would be very easy to hit that 200hp mark with low boost? at what boost are you required to upgrade to a 2 BAR?

[This message has been edited by timgray (edited 08-16-2007).]

Thanks guys!

Joseph: Wise man say: Listen to those who know, ignore those who blow smoke, and KEEP THAT #@&%# 3400 together as mother GM intended and Joseph recommends and make GOOD POWER WITH TURBO! This is one grasshopper that listens!

Hudini: Getting to talk to those guys is a WHOLE lot harder than you think! I tried that and found myself in that "Charlie Brown" state of mind. Wah......Wah.....Wah Wah Wah! The marketing people are much easier!

I am working on those contacts to help out fellow turbo'ers get upgrades.....definitely a little tougher....but trying.

I used a high volume pump because of 3 things: remote filter, remote cooler, and turbo. The oil feed is off a T with the oil pressure sending unit at one end and a 1/8 male NPT to -4 male AN fitting on the T. The other end of the T is a small 3 inch 1/8 male NPT brass tube to connect the adapter that Rodney sells for the 3.4L conversion. It just moves the assembly out a few inches to clear the adapter for the remote filter. With A/C cars you would need to account for the compressor. Oil return consists of drilling a 1/2" hole in the oil pan near the top. Then welding a 1/2 female NPT 45 degree elbow on the oil pan to accept a 1/2 male NPT to -8 male AN fitting. You want the return a 1/2" so oil flows freely back to the pan. I looked all over and found the best spot (for me) was right below where the a/c compressor would be if I had one. You can pick any spot that won't be blocked by something like the starter, etc. You can use all NPT stuff from the hardware store if AN stuff is too expensive for your build. Just use barb fittings where I used AN fittings. Then use the hose of you choice. I'm using SS braided hose just for strength, abrasion/heat resistance, and looks.

[This message has been edited by Hudini (edited 08-18-2007).]

quote Originally posted by timgray: at what boost are you required to upgrade to a 2 BAR?

Since the normal operation of the intake is always at a negative pressure I'd say as soon as you get into a posative pressure situation you'd want to have it in the system BUT it has to be enabled by the ECM.

Good luck!

------------------

quote Originally posted by timgray: Intakes for the turbo. Use the stock airbox or ditch it? How about exaust feed? Did you modify a stock crossover pipe or build your own? adapter plate tips? What mistakes did you make that someone else could easily fall into on the intake side and the exaust side? What kind of intake pipe did you use? aluminum with silicone joints? all steel welded? why?

The stock airbox would work if you have room to mount the turbo with it in place. I removed mine to put a trans cooler in that spot. Now if you look at Dennis's pictures you'll notice how he mounted his turbo with the turbine section towards the front of the car. It appears he mounted it directly to the Y pipe. The turbo would need some kind of support because it's too heavy to hang on the pipe without cracking the welds. The turbo intake is on the back of the car and you cannot easily reach the air box. I mounted mine on a home made crossover that connects the 2 stock manifolds. The turbine section is towards the rear of the car. This allows air to be drawn from the area where the stock air box used to be. I did this to route the exhaust down by the trunk for the shortest route possible. My big mistake was not using expansion joints on the original crossover. Expanding pipes bend things. I used 8 gauge mild steel weld els. They are cheap and strong. Stainless steel is the best material to use but takes a little more care to weld and it's relatively expensive. The intake is cheap 3" PVC coupled with rubber pipe adapters (used on cast iron drain pipes mainly) It has high crush strength and is away from high heat plus it does not conduct heat well. As you can tell, cost is a factor for me.

Here is another calculator: http://www.squirrelpf.com/turbocalc/index.php

Does anyone have some good VE numbers for the 2.8L (and 3.4L if you have them)?

quote Originally posted by Hudini: Does anyone have some good VE numbers for the 2.8L (and 3.4L if you have them)?

Hudini, I find this an interesting thread, so I hope this answer to your question helps.

On page 94 of his book, "High Performance Fieros," Robert Wagoner lists the MAXIMUM volumetric efficiency of the 2.8L Fiero as 0.83 at 3600 RPM. My interpolation from a graph he also shows on page 94 of that book indicates the VE for that engine declines to about 0.71 at 5200 RPM.

I can't vouch for the accuracy of his numbers, but at least they make sense in that the maximum VE he reports for the Fiero 2.8L is much lower --- and occurs at a lower RPM ---than the maximum VE he shows for various incarnations of the LSx engines in recent years of the Corvette. For example, he reports the 2001, 2004, 2005, and 2006 Corvette LSx engines as having a maximum VE ranging from 0.99 at 4000 RPM, to 1.05 at 4800 RPM.

[This message has been edited by project34 (edited 08-18-2007).]

Those numbers do help, thank you. I think the Vette benefits from tuned port ram effects to produce nice pressure waves which fill the cylinder over 100% N/A. Our numbers do not surprise me. I wonder how much we can raise the VE by adding a turbo to the stock intake? It's going to be fun finding out. I bought my oil feed line today. 5' of SS braided hose with crimped female -4 AN fittings - $17. Got to love the local hose company. The hot rod shop would have been 3 times that.

quote Originally posted by Hudini: I wonder how much we can raise the VE by adding a turbo to the stock intake?

On page 36 of the book I cited earlier in this thread, author Wagoner's contention is that volumetric efficiency actually DECLINES with a turbocharger, which at first glance might seem counterintuitive. The rationale he affords for that assertion essentially is that the addition of a turbocharger introduces an additional restriction in the engine's intake and exhaust system. ("By adding the turbocharger, the intake and exhaust plumbing has been modified, and the [air] flow is reduced.")

Conversely, if reducing intake or exhaust flow reduces VE, this seems to imply that improving either one ought to increase VE.

Thus, for example, given the notorious restrictiveness of the stock intake manifold in the 2.8L V6 Fiero, it would seem to follow that a turbocharger on that engine should produce more power with a more efficient intake manifold than with the stock one.

Also, at higher RPM, the limitations imposed by the restrictiveness of the stock intake on the 2.8L V6 are probably only magnified with greater engine displacement, like that afforded by the 3.4L engine swap. Put simply, for a 3.4L in particular, a turbo on a Trueleo intake manifold (or any other more efficient intake) presumably should produce more power for us than would a turbo on a stock Fiero intake manifold.

Excellent thread. I might eventually boost my Aurora (once it's running) so I had this thread going for background info. Might as well add it to the info here: https://www.fiero.nl/forum/Forum2/HTML/081033.html


bob

I plugged the Aurora's 4.0L and a max power 6400 rpm figure (guess) in this calculator http://www.turbofast.com.au/TFmatch.html and it spat out the GT25 with .64 a/r (Garrett calls it 62 trim). Raising the max RPMs to 7000 and going to 8 psi said switch to the .86 a/r turbine housing. This site lists slightly different a/r numbers than the Garrett website. Realize the GT25 lists for somewhere around $1000 new. A less expensive option is the proven T3/T4 hybrid.

Perfect info so far guys! More Exhaust questions.

Can the stock Fiero exaust Logs be used? will porting them give a benefit? It was mentioned that going to greater than a 2" diameter causes turbo lag problems. Will staying with the stock restrictive setup also cause problems?

[This message has been edited by timgray (edited 08-18-2007).]

Just to throw my experience in with my early 2.8L turbo setup; the stock 15 lb injectors ( if they are clean and operting up to spec) can supply enough fuel to 9 -10 psi of boost. The fueling tables in the ECM program must be changed (as well as the PE tables) and at WOT the injector duty cycle rises to 100% ( above the 80% recommended) However this is OK for the short W.O.T 15 second bursts (typical 1/4 mile) that your engine will be operating in.

------------------
87GT 3.4 Turbo- 0-60 5.2 seconds
2006 3800SC Series III swap in progress
Engine Controls, PCM goodies,
re-programming & odd electronics stuff
" I'M ON THE LOOSE WITHOUT THE JUICE "

quote Originally posted by timgray: Perfect info so far guys! More Exhaust questions. Can the stock Fiero exaust Logs be used? will porting them give a benefit? It was mentioned that going to greater than a 2" diameter causes turbo lag problems. Will staying with the stock restrictive setup also cause problems?

I used the stock (ported) logs because of cost. I also used 1.5" weld els for the turbo manifold as they are bigger than the stock logs but small enough to fit the T3 turbo flange. When you look inside the T3 turbine section you will notice it gets very small right before it goes into the turbine blades. You are looking for the exhaust to maintain high velocity which is why you can get too big.

I could have just cut a hole in the turbo manifold and welded on the turbo flange but wanted the exhaust gas pulses to hit the turbine blades and not each other. Just cutting a hole and welding on a flange would have saved space though. This pic shows what I did for the turbo manifold. SS would be better for heat retention, long life, and high velocity. I went for low cost. The expansion joints are critical as I learned the hard way.


This shows how small the T3 turbine section opening gets once into the turbine.

quote Originally posted by timgray: Can the stock Fiero exaust Logs be used? will porting them give a benefit? It was mentioned that going to greater than a 2" diameter causes turbo lag problems. Will staying with the stock restrictive setup also cause problems?

Perhaps the simplest answers to your 3 questions above are:
1. Yes.
2. Yes.
3. Yes.

More specifically, yes, you can run the stock Fiero exhaust manifolds, just as you can run the stock Fiero intake manifold. However, you can improve the engine's VE, especially at higher RPM, by improving the airflow of both, either with aftermarket solutions (e.g., a Trueleo intake and Sprint headers) or homemade ones (e.g., a dual plenum intake that is set up properly and one-off headers or porting of the exhaust manifolds).

I want to add that the following Thread is also full of great info about the crossover pipe to Turbo connection.

https://www.fiero.nl/forum/Forum2/HTML/082954.html

I should also hunt for other turbo threads that are full of good basic info and lost them here as well.

Any more tips and info on the exaust side? How about how to mount the turbo. How do you keep the weight of the turbo from cracking everything?

Also heat shielding, is it a good idea or a bad idea to put a heat shield around the turbo to keep from cooking everything?

Some folks do hang the turbo on the crossover. It all depends on the strength of the pipe and type joints used whether it will last. I welded a brace under mine that bolts to the trans. That was my initial problem with not using expansion joints. The welded/bolted brace had no give so the heat bent the crossover. Then when the crossover cooled it leaked.

I'm definitely going to use some type of shielding on the turbine section. With mine it's simply too close to the pipe between the compressor outlet and the throttle body. Also, keeping the exhaust gas velocity high is aided by keeping the heat inside the pipes and turbo. And on top of that, mine is mounted somewhat close to the decklid. Don't want to melt that.

quote Originally posted by Hudini: Anyone else know of a proven combination, one that you liked, ran well, not too big, not too little, etc?

Even if people don't know the model number of the turbo, specifying just the amount of boost that they've been running successfully, as well as the engine's compression ratio, likely also would be useful information for this thread.

The Garrett T-3 turbocharger comes in different sizes. It was not only used on the Ford 2.3L but also on the McClaren turbo setup offered on the 3.1L turbo Grand Prix and on the Buick Grand National 3.8L. What you say is true that the Ford 2.3L version works great on the 2.8L but it a bit too small on the 3.4L This can be solved by installing the Grand National compressor wheel on the Ford T-3 version or by starting out with a turbocharger that is correctly sized. As per Hudinis post do not oversize your turbo or oversize the diameter of your crossover pipe. Keep it at 2" OD and wrap it in heat shielding for strong low end perfromance.

quote Originally posted by Hudini: The T3 is a small turbo. It came stock on many OEM turbo cars like the 2.3L Fords. The 2.8L is only slightly larger so it's a pretty close fit. The 3.4L really pushes it too far as some have reported running out of boost at 5psi. (which is fine for me) Too small a turbo means the turbo cannot produce more boost even though the car produces more exhaust for the turbine (at high RPM). Too large a turbo means no boost is produced until high RPMs which means power comes on late, maybe past the power band. Here is a youtube video of G-pop Shop doing a rebuild. They sell lots of rebuild kits on ebay. http://www.youtube.com/watch?v=I2CwBwrdnvA At any boost you need a 2 bar (or higher) MAP sensor. 2 bar simply means 2 times the force of atmospheric pressure. Did you know you have 14.7 pounds of air pressure on you right now (at sea level)? That is 1 atmosphere or 1 bar. So to measure anything over normal atmospheric pressure you need a sensor capable of reading more than 1 atmosphere. So for any boost less than about 14.7 psi you get a 2 bar. (That's 14.7 atmosphere (1 bar) plus 14.7 boost (+1 more bar). So 30 psi turbos need a 3 bar MAP and so on.

------------------
87GT 3.4 Turbo- 0-60 5.2 seconds
2006 3800SC Series III swap in progress
Engine Controls, PCM goodies,
re-programming & odd electronics stuff
" I'M ON THE LOOSE WITHOUT THE JUICE "