I am wanting to put a 95 Northstar with the 4T80e into my 87 GT.

I have used the search on this site and I dont seem to be able to find anyone that has done the same thing. THey all seem to have switched up to a manual.

I would like to have some type of back ground on this installation. Can anyone direct me into the right direction for information?

I have heard that it can not be done cause of the OBD1 issue and some stuff about the PCM looking for other stuff and then makes it not run right, bla bla bla.

I want to do this very much. I have waited 26 years to find my perfect Fiero GT and now I want to put in what is in my mind one of the best engines ever.

I can't answer your questions, but I do have something for you to consider. One of the reasons people don't use the 4T80E is its massive 300 lb weight. That, coupled with the Northstar start adding up to a sizable change in the front to rear weight distribution. It's probably the least of your worries though considering the other problems I've also read about running the N*/4T80E combination as a stand-alone unit.

The biggest issue other than weight is the 2nd gear starts. I am working on that issue on my car now.
I will do my best to answer whatever questions you have, but I did not build this car.. Madcurl had the 4t80e and his ran fine with no 2nd gear start issue, He has since left the forum,, I tried asking him few questions about his but never got a reply then he left... I am adding wheel speed sensors and the EBTCM into mine, from what I read that seems to be the only thing in mine missing that will cause the issue..
My car ran pretty good especially on top end but pretty sluggish off the line, and so are most I have talked to that run the 4T80e, I hope to fix that soon in mine.. I am running obd1 with the factory ecm..

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


87 GT
series 1 3800sc (7.597 @88.53 1.579 60ft)
(series II swap in progress)
85GT Northstar/ 4t80e
86GT 3800 n/a
My Build

Get ahold of troy ritchie.. He works at Mr. transmission here in red deer..Google for the phone number. He will be able to help you out with this combo..

As an alternative idea, If you have the time and resources and are committed to that idea, I suggest considering a modified torque converter from CHRfab to adapt the N* to a non electronic 4T60. They're cheap and easy to find.

The starter fits in the 4T60 bellhousing, bolt pattern is very close, different stall speeds available, axles fit and there are people who have used a built 4T60 against nitrous fed LT-1

Stand alone computer would allow you to turbo or a modified supercharger, belt driven etc. You could force massive amounts of air and fuel through it, lots of different combinations, complete Shelby series 1 motors have sold on EBay for cheap.

[This message has been edited by rourke_87_T-Top (edited 09-05-2013).]

So what stand alone computer are we talking about?

And what would the issue be with using the STOCK ECM with this system? If I am using the whole drivetrain and the stock wiring harness what would be the problems?

I have installed a 3800 L67 into an older 96 GTP and didnt have any issues with the way that it ran and I used its stock ECM.

Thanks

Shelby series 1 engines were the olds aurora engine. Ryan Hess has a N* with the 4t80e and a tap shift that he engineered. The last I heard he was wishing that he had the 4t65e hd for the 100 lb weight saving. Fieroaddictions turbo N*, he chose the 4t65e hd for his car. The 4t65e hd has a lot of aftermarket build parts available and I'm not sure that anyone has any thing that will make the 4t80e stronger.

for him to run all these mentioned he is going to have to convert to OBDII correct?

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


87 GT
series 1 3800sc (7.597 @88.53 1.579 60ft)
(series II swap in progress)
85GT Northstar/ 4t80e
86GT 3800 n/a
My Build

No.

quote Originally posted by dratts: ... Fieroaddictions turbo N*, he chose the 4t65e hd for his car....

What did he use for a torque converter / flexplate ? To adapt the different sizes / pattern ?

REPOST**

So what stand alone computer are we talking about?

And what would the issue be with using the STOCK ECM with this system? If I am using the whole drivetrain and the stock wiring harness what would be the problems?

I dont think anyone can answer this correctly. Cause it only makes sense that if you are removing the Engine and Transmission from the donar car complete with harness and ECM then it should work.

well thet are a lot more issues than just drivetrian and computer... the computer looks for lot more info from sensors the fiero doesn't have... wheel speed sensors etc.. my car was built back in 1997 and I guess the p.o. was content .. I am trying to work out the issues he left alone..
I have not considered the above options cause I thought Id have to convert to obdII.. all the work I have put in I would hate to pull back apart and go another direction ..

------------------ sorry, was thinking of the 7730 ? or whatever pcm and having to convert to obdII


87 GT
series 1 3800sc (7.597 @88.53 1.579 60ft)
(series II swap in progress)
85GT Northstar/ 4t80e
86GT 3800 n/a
My Build

[This message has been edited by jb1 (edited 09-06-2013).]

http://www.chrfab.com/new_products.htm

Yeah I was checking out the Holley EFI. But it says it only works with a 4L60 or 4L80, and I dont know if the N* works with these?

It also says that the 95 N* Computer is a chip modifiable ECU and they use them.

quote Originally posted by rourke_87_T-Top: What did he use for a torque converter / flexplate ? To adapt the different sizes / pattern ?

Sorry, I have his car, but I don't know what flex plate or torque converter issues he had.

quote Originally posted by Inferno: But does the 4T65E-HD bolt up to the N* and the Flywheel and TQ converter work directly? Or can you use the 3800L67 FLywheel and TQ Converter?

No they do not go together.

quote Originally posted by Inferno: Yeah I was checking out the Holley EFI. But it says it only works with a 4L60 or 4L80, and...

"...and T transmissions"

Is there a reason the Northstar flexplate won't work with the 4T65E converter?

quote Originally posted by Inferno: REPOST** So what stand alone computer are we talking about? And what would the issue be with using the STOCK ECM with this system? If I am using the whole drivetrain and the stock wiring harness what would be the problems? I dont think anyone can answer this correctly. Cause it only makes sense that if you are removing the Engine and Transmission from the donar car complete with harness and ECM then it should work.

As I mentioned on RFT, the stock computer has been used.
HOWEVER, people who have done so have had varying results. Jon Lagler/Rockcrawl/FieroAddiction seem to have gotten it to work. Some others have not.

I tried the stock chip when I first did my swap, but without the automatic transmission, it was useless. I don't have first hand experience more in-depth than that.

As far as control options for the transmissions goes... the basic shift solenoid logic for the transmissions is straight-forward. However, the pressure control solenoid and torque converter clutch solenoid operation strategies change over time and with different transmission families... so something that runs one transmission may not necessarily run others.

[This message has been edited by Will (edited 09-07-2013).]

quote Originally posted by Will: Is there a reason the Northstar flexplate won't work with the 4T65E converter?

They don't just bolt up, need to adapt them. 3 lug converter pattern to the 4 lug pattern on the N* flexplate, yes they can and have been adapted, with ring on the converter or by modifying the flex-plate.

quote Originally posted by rourke_87_T-Top: "...and T transmissions"

My mistake yes it does.

Did Jon build another N*? The one I got from him has a Holly Commander computer.

quote Originally posted by Will: Is there a reason the Northstar flexplate won't work with the 4T65E converter? As I mentioned on RFT, the stock computer has been used. HOWEVER, people who have done so have had varying results. Jon Lagler/Rockcrawl/FieroAddiction seem to have gotten it to work. Some others have not. I tried the stock chip when I first did my swap, but without the automatic transmission, it was useless. I don't have first hand experience more in-depth than that. As far as control options for the transmissions goes... the basic shift solenoid logic for the transmissions is straight-forward. However, the pressure control solenoid and torque converter clutch solenoid operation strategies change over time and with different transmission families... so something that runs one transmission may not necessarily run others.

Ok so........

It seems that I maybe looking at swapping in a Manual Transmission.

HELP!

What transmissions are usable? And to be clear does that then mean that I can use my 95 N*? And what computer (ECM) would I use then? Stock reflashed? Stand Alone? LS1?

Help me nail this down guys. You are all the experts on this stuff, everyone knows this.

You can use any transmission that was used on the Fiero (5 speed Isuzu, 4 speed Muncie, 5 speed Getrag), or the F23 (new GM compact cars) or the F40 (Pontiac G6, Saab) with the least amount of modifications since the bellhousings have similar (but not exact) bolt patterns. I've listed the transmissions in order of increasing strength, complexity to install, and cost to install, and although I wouldn't use the Isuzu, I've listed it anyways.

You can use your 95 Northstar on any of these transmissions. For PCM's, there are solutions for OBD1 (Ryan Hess' 7730 retune), OBD2 (stock reflashed from Westers Garage in Alberta, and LS1 reflashed), as well as aftermarket ones too. All have had varying degrees of success with controlling the Northstar but none are perfect and all require you to be able to some software modifications to suit your particular car. There's a couple threads here on PFF discussing the pros and cons and some go into lengthy detail describing what people have had to do to make things work. It would take five pages of text to summarize each option from the thousands of posts about this subject and everyone has a different idea of what's best. Your best bet is probably to use the search function using the words Northstar (or N*), PCM, OBD1, Hess, Ajxtcman, Will, gsxrbobby, zac88gt, OBD2, CHRFab, and those will lead you to others as well. Be sure to include the archives in your search.

quote Originally posted by dratts: Did Jon build another N*? The one I got from him has a Holly Commander computer.

I assume he did for a customer, as I he posted the info I mentioned on this forum

quote Originally posted by Inferno: Ok so........ It seems that I maybe looking at swapping in a Manual Transmission.

Uhh... Why?

There are aftermarket controllers, such as the aforementioned Holley that can control the transmission. It just takes money.
I think by the time you source a transmission, have the flywheel modified, secure a clutch... you'll be out more money than if you bought an aftermarket controller.

[This message has been edited by Will (edited 09-09-2013).]

From my research already, using the Holly system has issues and doesn't completely work with the 80e. Unless you can point me in a direction that I have not read about.

If I go with a Manual it will be the F40 so long as I can find one for a decent price. Not many around my area right now yet at any salvage yards.

If an MR2 owner can get his to work then I should be able to as well.

If you decide on the f40, I have two of them, both 0 miles. I don't remember what my plan was but they were cheap so I got two of them. One for a back up. I'm not going to be using them now.

quote Originally posted by dratts: If you decide on the f40, I have two of them, both 0 miles. I don't remember what my plan was but they were cheap so I got two of them. One for a back up. I'm not going to be using them now.

Thanks for the offer, but I would have to believe that shipping to Edmonton, Alberta Canada would be a killer.

quote Originally posted by Inferno: From my research already, using the Holly system has issues and doesn't completely work with the 80e. Unless you can point me in a direction that I have not read about.

I haven't read anything about the newest Holley and the 4T80E, so I can't comment.

Aftermarket controllers:
http://www.summitracing.com...smission-controllers
http://www.usshift.com/

There are a LOT of these on the market... Google is your friend.