What size are the compressor A/R and turbine A/R on your GM4? I can't seem to find the bracket in your photos, where in relation to the turbo is it? The T4 looks like it would orient nicely for me in the engine bay since I'm planning on running an intercooler rather than alky injection... but I was really hoping to imitate your setup as close a possible in order to use the final chip burn you and Rockcrawl come up with save me alot of testing, guessing, and work. Choices choices. Thanks again for some more brain picking. Maybe if I match the A/R's I might still have a chance.

There's another route you could have gone with the computer, the 1227730 and 1227727 are electrically identical. The 1227727 came in the 1989-90 Grand prix witch was available with a turbo. So, there is the code out there that supports boost for your computer. The only problems, its a 6 cyl, only 3.1L displacment and uses DIS ignition. But it is something to look into. The code also has provisions for an electrically operated wastegate.

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

"How do I get one of those Smileys that rolls back and forth accross the screen?" -Archie

Actually, I'm goign to be forced to use a better turbo. Since I'm using an intercooler I'm going to have to figure in pressure drop. From what Pete is saying, I don't think the GM4 will support 5-7 PSI with and intercooler. Luckily the T4 is more popular and will probably be able accomodate my needs easier. That is if I am correct in assuming that a T4 can make the boost I need.

PBJ, Rockcrawl, that chip (when it is ready)is the missing link. If a different turbo is putting out the same PSI on the same motor, is it still similar enough to run descent with that program (with an MSD boost retard box)?

The turbo bracket came off the 3 bolt holes in the back of the rear head. It came up enough to clear the oil filter, then out to support the turbo.

Rockcrawl and I discussed the use of the 727, but as you mensioned is DIS. We found on our road test with the 5 psi boost and what was available to us now, ie fuel mapping (Time), and manual waste gate control (free-$40.00), exteranl boost retard module($160.00 or ebay), we can control the upgrade well. and within a reasonable price as compaired to going and buying more ecm's and so on.

As for the intercooler, I was told it was not neccessary for 5 psi, but would look nice. I was also told water injection was not neccessary at 5pis, I did it just because I could-likely you are the same way about the intercooler.

I am sure if our 730 prom could be set up for any similar system. but its not proven yet.

I don't know what compressor size I have, since I was not going to look into it untill I had a problem with no boost. Since I don't its bumped down on priority-sorry. (stock anyways)

Pete

I'm guessing that the GM4 doesn't have that many options when it comes to A/R's, if any at all. So I could probably just look up the stock specs. Good luck with the rest of the tuning.

Can you tell us a little bit about the wiring? Did you keep anykind of a chart or diagram of it? Maybe Rockvrawl can give you a little space on his site for some details about this like a grocery list and such.

quote the 1227730 and 1227727 are electrically identical....

I'm aware of the TGP code. FYI, the 1227749 is a just 1227730 with two different drivers. We decided it wouldn't be good use of time to try the TGP code, only to risk having the same kind of problems and even more due to the DIS/DIST incompatibility. It's not the ECM that's giving us trouble, it's the SyTy code. Just for S&G, we plugged the 730 memcal into the 749 and the car ran great. I'm going to wire one of my own cars for a 749 so I can tune it here in PA whithout time constraints. When I get it right we'll just need to fine-tune the turbo related portions on Becky's car (I don't have a turbo). Until then, the car will continue to run on the 730 chip that I developed two years ago for my first Cadero, but with the MSD BTM to handle the timing under boost. The 749 would be better, but it'll take some time. I remember how much time I spent with the 730. I bet I burned 100 proms or more.

So the 749 can use a 730 PROM and work just like a 730? And the car runs pretty good on a N/A chip with the MSD box?

Also another question. Pete, you said you were running a boost controller. Is 5-7 PSI all you can get even with the controller? Or is it not installed yet? Would you think a boost controller, manual or electric, would allow the turbo to produce more boost (like around 6 or 7 PSI with an intercooler)?

I can not say exactly what the turbo is going to put out, like I said the seal blew out on top of the throttle plate. We did see over 5 psi on the gauge as the seal was blowing out and held 5 once the seal had failed. The turbo waste gate was not controlable by the 730 ecm and wired to have full boost. During the road tests the ecm was hacking at ignition timing because we have not got a boost timing master yet. We did not have alot of road test because of road condition and time and lack of "proper" documenation on the vehicle (if you know what I mean"

I think this turbo will put out more boost, but it is definatly on the big side for this motor, with the motors low end torque it worked well so far.

Pete

quote Originally posted by FieroGTT: Is 5-7 PSI all you can get even with the controller? Or is it not installed yet? Would you think a boost controller, manual or electric, would allow the turbo to produce more boost (like around 6 or 7 PSI with an intercooler)?

Man oh man, let's not get too greedy here people. I think PBJ definately has the right idea with his 5 lbs. of boost. The Caddy 4.9 has 9:1 compression if my memory serves me right, and it's known to be a motor that is known to not be too kind to head gaskets when stressed....although the later motors are a lot better than the earlier ones were in that reguard. It's due to the aluminum block with cast iron heads design.

For those that have driven 4.9 powered Fieros (I've driven Ed Park's twice and pushed it pretty hard) the engine definately isn't lacking in power, especially off the line with all that torque on tap, it just runs out of breath in the upper end. The intake manifold and cylinder heads just aren't designed to flow that much air at high rpms normally aspirated. A little bit of boost forcing air down those small passages should overcome this problem quite nicely without stressing the engine too much.

Ken S.

With all the precautions such as the intercooler, bov, and MSD box I don't see 7 psi being too much of a problem. Boost usually doesn't magically blow a motor, detonation does. 5 psi is a great place to start, but I want to make sure I have the ability to up the boost a bit if the engine proves it can be handled.

Ahhh...now I see, the turbo isn't running out of air...the motor just isn't spooling it up to a higher psi. I think you're right, you will definitely see more boost once everything is sealed.

I would encourage anyone to boost the 4.9 above and beyond 5 psi. That way I will know if I should run less boost than 5 psi or still be grinning happy with the 5 psi I told myself I would limit the boost too. I am not trying to break any thing with this turbo set up, including records, engines or other peoples 1/4 miles.

Just having fun with testing my and other peoples skills on an area with little to compair too.

This car is my wife's daily summer driver remember.

Pete

Ugh..., PBJ you make me feel like such a slug. I haven't looked twice at my winter projects and there you are finishing a turbo project AND installing a dash. Good God man! What drives you?

Keep up the amazing work. You're an inspiration! (+'s) to you and herGT Now if I could just get off my lazy duff...

quote The Caddy 4.9 has 9:1 compression

Actually it's 9.5:1, 5psi is plenty. When (I mean if ) she blows a head gasket, Pete can hog out the heads and use Quad4 pistons to get it lower.

Pete,

I would not waste the money on the MSD BTM box. For the same money, you can buy hardware to write chips and Terrys software.

The problem is fuel needs to be controled also and some RPMS might need to be retarded more then others and not linear like the BTM does it.

Howard, You missed something. The BTM is temporary until we get the Syclone code working. The TPI code doesn't recognize anything above 0 manifold pressure. Besides, I'd bet most aftermarket or homebrew turbos and superchargers are using a BTM or no boost timing control at all. $160 and 30 minutes or less to install vs $300+ and several weeks of tuning. The BTM doesn't look too bad.

quote Originally posted by blakeinspace: Good God man! What drives you?

I am starting to get nervous about next winter. What will I come up with to do.

quote Originally posted by PBJ: I am starting to get nervous about next winter. What will I come up with to do.

You are going to come down to WV, stay a couple weeks, and help with my 85GT 86GT and 87GT, they all seem to be missing something..... oh yeah TURBO ive got a stock 2.8L in my 85 and 86GT and ive got a 70-80k mile 3.4L in my 87GT i think turbo will help them quite a bit. so when you get time, just come on down to west virginia, ill let you drive the cars through route 60 clear into rainelle WV, from gauley bridge WV to rainelle WV i would say you will have more road turning fun than anywhere else on the east coast!!!

come on down.

matthew

[This message has been edited by PBJ (edited 01-09-2003).]

quote Originally posted by PBJ: I am starting to get nervous about next winter. What will I come up with to do.

Don't worry, I'll keep you busy with ideas

quote Originally posted by PBJ: I am starting to get nervous about next winter. What will I come up with to do.

i got an idea, right, you do the same swap to my car for free. its something thats never been done before and will astonish everyone, you wanna be different right?

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

--Adam--
1987 Blue GT 5-speed
IM AOL: GTFiero
Fiero mods almost done...i know that because im running out of possesions to sell for money

Wahh...whole page and NO PICS!

quote Originally posted by USFiero: Wahh...whole page and NO PICS!

Well. . .we can't have that! I'm trying to build a reputation here! My user name should be Her86GTpics. . . But I would like to have more of this in the summer:

Jon, I didnt miss anything. I think its a waste of $160. And who cares, what everyone else is doing!??! I know my next homebrew turbo system is going to be running Motec. (the sportswagon needs a kick in the pants)

And about the 1 bar problem, I am sure you guys are smart enough to make a 2 bar map work.

It should just be a different signal. If you can write all the tables in the PROM, you can change them to work with the new signals that the 2 bar provides. Im no EE though. You could hook one up to a scope with a vaccuum source or ask Terry to know for sure.

I just dont think performance is going to be optimal with the BTM and a rising rate fuel pressure regulator.(You havent said that youre using one yet, but I have a feeling youre going to go there for fuel management)

Pete, I wish you the best of luck and do not mean to be negative. However, I researched buying one of those myself, and did not feel it was worth buying.

looks like I scared PBJ into editing his post away

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

I really hate to get anywhere near off topic on a topic like this that im really going to devote alot of time to....but....Is it just me or are Her86GT and PBJ the cutest thing you've ever seen? Rockcrawl, first hand opinions?

Ok, a little turbo just to be fair. How easy will the 749 ECM and custom PROM swap into your setup (aside from the actual tuning)

quote Originally posted by FieroGTT: How easy will the 749 ECM and custom PROM swap into your setup (aside from the actual tuning)

the 730 to 749 swap would be about 2 min worth of wire changes at ecm, re plumming turbo for ecm control instead of manual control and swaping map sensor for 2 bar. Not very long at all.

Pete

quote Originally posted by FieroGTT: Is it just me or are Her86GT and PBJ the cutest thing you've ever seen?

Awe! Thanks eh. . .not bad for being married 9 years We're just lucky we have the same hobby.

quote Originally posted by Standard: .2 ft/lb's of torque! must be a screamer!

That's about what a Quad 4 puts out below 3000 rpm, isn't it?

Rob

...Donning Flameproof undies...

------------------
86 SE V6 4 Speed

Damn, I've been out of touch with this topic too long. I was in London on the 4th helping a friend move there from whitby. I missed out on an awsome time to see the car and meet rockcrawl!

My friend probably 15 min away from you. Just up wonderland road and make a right at Springbank. Can't miss his place, just accross from the cemetary.

Can't wait to see the car this summer. Spin them tires!!

Just wanna bump this back to the top. Anyt more progress guys?

Did some more cleaning up on the engine to get it Carlisle ready. We are just waiting for the MSD 6BTM boost timing master. Once everything is put together and running smoothly, we will hopefully have dyno results available. The dyno results we are really waiting for will be done at Carlisle. I will post some more pics once the engine looks show-ready.

quote Originally posted by Rob Ernst: That's about what a Quad 4 puts out below 3000 rpm, isn't it? Rob ...Donning Flameproof undies...

LOL sometimes I think that's not far off

I don't think it's too bad, considering I have .5 litres less displacement than a 2.8, and make 50 more hp and only 5 ft/lbs less torque

I don't think it was mentioned before...but what clutch are you using with this setup? What clutch do you think could handle this setup?

quote Originally posted by FieroGTT: I don't think it was mentioned before...but what clutch are you using with this setup? What clutch do you think could handle this setup?

its an Automatic

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

--Adam--
1987 Blue GT 5-speed
IM AOL: GTFiero
Fiero mods almost done...i know that because im running out of possesions to sell for money

I have done some "cleaning" up of the wires and such.

before

now

its getting there

Pete

Can you believe that it took us three hours to clean it up and make it look like that! I love the detail stuff - you wouldn't want to see the way Pete would leave it. . .he figures, it's done when you can drive it not when it LOOKS GOOD!

I drove it today for the first time - mind you it was just around the dealership parking lot, but WOW, does it ever go! ! !
I think it might be on the road sooner than it was last year

[This message has been edited by Her86GT (edited 01-21-2003).]