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What is the max horsepower a 1987 V6 5 speed can handle? by slider
Started on: 09-06-2016 09:49 PM
Replies: 22 (1259 views)
Last post by: Dennis LaGrua on 09-09-2016 02:11 PM
slider
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Report this Post09-06-2016 09:49 PM Click Here to See the Profile for sliderSend a Private Message to sliderEdit/Delete MessageReply w/QuoteDirect Link to This Post
Just wondering if it can handle a turbo without mods
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Report this Post09-06-2016 09:53 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Without mods? No. Turbo will require some modifications, like a different MAP sensor, possibly better ignition, different spark plugs, and a reporgrammed module for the ECM.

I wouldn't put more than about 8 PSI through a stock 2.8 though.
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slider
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Report this Post09-06-2016 10:10 PM Click Here to See the Profile for sliderSend a Private Message to sliderEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks for the reply sorry I was a little vague.
From what I have been reading it sounds like a good idea to change out some of the ignition components. A better coil such as Accel is affordable.

Will my 5 speed handle the extra hp with out changes?
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Report this Post09-06-2016 10:16 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by slider:

Thanks for the reply sorry I was a little vague.
From what I have been reading it sounds like a good idea to change out some of the ignition components. A better coil such as Accel is affordable.

Will my 5 speed handle the extra hp with out changes?


I don't know what the condition of your clutch is, but it might be a good idea to upgrade it too. Just don't try to launch hard on boost or shift hard into peak boost and you should be fine. People run the Getrag with 4.9 and 3800 swaps, so a 2.8 with a small turbo at ~8 PSI peak should be fine, as long as the clutch is good and you don't thrash it to pieces.
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Blacktree
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Report this Post09-06-2016 10:17 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageSend a Private Message to BlacktreeEdit/Delete MessageReply w/QuoteDirect Link to This Post
Transmissions are actually rated for torque, not HP. But a mildly turbocharged 2.8 V6 shouldn't be too much for it.
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Report this Post09-06-2016 10:26 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Oh, and you'll need injectors. I'm not sure which other injectors fit exactly, but I think I've seen Mustang 17 lb-hr injectors mentioned before that can be used.
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Report this Post09-07-2016 06:39 AM Click Here to See the Profile for MonkeymanSend a Private Message to MonkeymanEdit/Delete MessageReply w/QuoteDirect Link to This Post
I've got a naturally aspirated 3800 with the stock 5 speed Getrag (and a Spec 3+ clutch). I rarely launch hard but I haven't had ANY slippage and nothing's blown up.
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slider
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Report this Post09-07-2016 08:43 AM Click Here to See the Profile for sliderSend a Private Message to sliderEdit/Delete MessageReply w/QuoteDirect Link to This Post
Lots of great info here! thanks!

Where do I get a Getrag trans? Is this after market or did they come from the factory on GM cars?
My 96 Camaro had a 3800 is this where you got it from or I suppose there were plenty of Gm's that came with this
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2.5
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Report this Post09-07-2016 09:02 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
5 speed getrag torque specs were originally underrated.
It was rated: "the gearbox is only rated for 200 ft-lb."

Quite a few people run them on V8s and 3800s

Fieroguru ran 317 torque at the wheels

[This message has been edited by 2.5 (edited 09-07-2016).]

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2.5
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Report this Post09-07-2016 09:10 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post

2.5

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Member since May 2007
 
quote
Originally posted by slider:

Lots of great info here! thanks!

Where do I get a Getrag trans? Is this after market or did they come from the factory on GM cars?
My 96 Camaro had a 3800 is this where you got it from or I suppose there were plenty of Gm's that came with this



"'86-88 2.8L 5-speed "Getrag": This exact transmission is unique to the Fiero. According to the Hollander manual, five-speed transmissions from the cars below can be used if the shift arm is rotated 180 degrees. However Rodney Dickman (rodneydickman.com) advises this information is incorrect. Rodney makes a hardware kit which will allow these transmissions to be used with the Fiero. Transmissions which will work are: Cadillac Cimarron '87-88 gear driven speed sensor
Chevrolet Beretta '87-89 2.8L gear driven speed sensor
Chevy Cavalier '87 2.8L five speed, w/electronic speedometer
Chevy Cavalier '88-89 2.8L electronic speedometer
Chevy Celebrity '87-88 gear driven speed sensor
Chevy Corsica '87-89 2.8L gear driven speed sensor
Pontiac 6000 '87-88 gear driven speed sensor
Pontiac Tempest '87-89 2.8L gear driven speed sensor


Five-speed Getrag transmissions from the cars below can be used in the '86-88 2.8L 5-speed Fiero by switching the speed sensor, shift arm, and/or speedometer cable. The shift arm must use the Rodney Dickman kit to work.
Cadillac Cimarron '87-88 cable drive speedometer
Chevy Cavalier '87 2.8L five speed w/cable drive speedometer
Chevy Cavalier '88-89 2.8L cable drive speedometer
Olds Firenza '87 2.8L five speed


Other 1987-94 GM cars (Pontiac Grand Prix, Pontiac Grand Am, etc.) used a similar Getrag 5-speed transmission but the linkage system for the slave cylinder and release arm is different than the Fiero. On these transmissions the release arm is inside the transmission and the slave cylinder mounts to the bell housing. Rodney Dickman offers an adapter that allows this version of the Getrag 5-speed to be used in the Fiero.

http://fierosails.com/TransMan.html


Another source of info:
http://www.rodneydickman.com/n11.html

[This message has been edited by 2.5 (edited 09-07-2016).]

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slider
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Report this Post09-07-2016 09:19 AM Click Here to See the Profile for sliderSend a Private Message to sliderEdit/Delete MessageReply w/QuoteDirect Link to This Post
Excellent sources thanks!
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Report this Post09-07-2016 05:36 PM Click Here to See the Profile for BillSSend a Private Message to BillSEdit/Delete MessageReply w/QuoteDirect Link to This Post
No problem with 7-8 psi using stock injectors. Any more and you really want forged pistons and knock sensing (I ran 12 psi with larger injectors)
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slider
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Report this Post09-07-2016 06:43 PM Click Here to See the Profile for sliderSend a Private Message to sliderEdit/Delete MessageReply w/QuoteDirect Link to This Post
How much hp increase can I expect with 7 - 8 psi on a V6? Or maybe I should ask how much
torque increase.
Or does it depend on too many things?

[This message has been edited by slider (edited 09-07-2016).]

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Report this Post09-07-2016 07:09 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by slider:

How much hp increase can I expect with 7 - 8 psi on a V6? Or maybe I should ask how much
torque increase.
Or does it depend on too many things?



Roughly 50% when that much boost is being made. The thing is that you aren't going to make peak boost through the entire RPM range.
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slider
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Report this Post09-07-2016 07:20 PM Click Here to See the Profile for sliderSend a Private Message to sliderEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks for answering!

50% of the current hp? I've heard differing ratings for the V6 this is an 87 SE. I've heard 120 and 145.
Can it be setup to be strong in a RPM range of your choosing? For example I like the mid to high end.
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Report this Post09-07-2016 07:42 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by slider:
Thanks for answering!

50% of the current hp? I've heard differing ratings for the V6 this is an 87 SE. I've heard 120 and 145.
Can it be setup to be strong in a RPM range of your choosing? For example I like the mid to high end.


Stock HP rating is 135-140 for the 2.8. With 8 PSI peak boost, you can expect around 200-210 HP at the crankshaft.

As for where it will be strongest, it's just a matter of how you tune the setup.
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Report this Post09-08-2016 02:00 AM Click Here to See the Profile for garage monsterSend a Private Message to garage monsterEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by slider:

Where do I get a Getrag trans? Is this after market or did they come from the factory on GM cars?
My 96 Camaro had a 3800 is this where you got it from or I suppose there were plenty of Gm's that came with this


Not sure about this question. I believe the 5 speed transaxle in an 87GT is a Getrag. Mine was until I swapped in a later model 6 speed.

BY the way, I run a 383 sbc and never had trouble with the Getrag
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Report this Post09-08-2016 08:41 AM Click Here to See the Profile for fierosoundClick Here to visit fierosound's HomePageSend a Private Message to fierosoundEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by slider:

Where do I get a Getrag trans? Is this after market or did they come from the factory on GM cars?
My 96 Camaro had a 3800 is this where you got it from or I suppose there were plenty of Gm's that came with this


The Fiero uses a transaxle like a FWD (front wheel drive) car. The Camaro doesn't.

 
quote
Originally posted by 2.5:

Rodney makes a hardware kit which will allow these transmissions to be used with the Fiero.
Transmissions which will work are:
Cadillac Cimarron '87-88 gear driven speed sensor
Chevrolet Beretta '87-89 2.8L gear driven speed sensor
Chevy Cavalier '87 2.8L five speed, w/electronic speedometer
Chevy Cavalier '88-89 2.8L electronic speedometer
Chevy Celebrity '87-88 gear driven speed sensor
Chevy Corsica '87-89 2.8L gear driven speed sensor
Pontiac 6000 '87-88 gear driven speed sensor
Pontiac Tempest '87-89 2.8L gear driven speed sensor

Five-speed Getrag transmissions from the cars below can be used in the '86-88 2.8L 5-speed Fiero by switching the speed sensor, shift arm, and/or speedometer cable.
The shift arm must use the Rodney Dickman kit to work.
Cadillac Cimarron '87-88 cable drive speedometer
Chevy Cavalier '87 2.8L five speed w/cable drive speedometer
Chevy Cavalier '88-89 2.8L cable drive speedometer
Olds Firenza '87 2.8L five speed




More here: https://www.fiero.nl/forum/Forum9/HTML/000038.html

I installed a NOS FWD Getrag in my Indy.
https://www.fiero.nl/forum/F...3/HTML/000077-6.html


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Report this Post09-08-2016 08:51 AM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by garage monster:
Not sure about this question. I believe the 5 speed transaxle in an 87GT is a Getrag. Mine was until I swapped in a later model 6 speed.

BY the way, I run a 383 sbc and never had trouble with the Getrag


Yes, the stock 5 speed in all V6 Fieros was the Getrag 282. The only way it wouldn't be the 282 is if someone swapped a different trans in, it was a 4-speed (85-86), or an automatic.
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slider
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Report this Post09-09-2016 11:20 AM Click Here to See the Profile for sliderSend a Private Message to sliderEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by garage monster:


Not sure about this question. I believe the 5 speed transaxle in an 87GT is a Getrag. Mine was until I swapped in a later model 6 speed.

BY the way, I run a 383 sbc and never had trouble with the Getrag


Forgive my ignorance sbc? Small block chevy?

Did you have to beef up the suspension quite a bit for the additional weight?
I realize I'm getting a little off topic from the original question
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Report this Post09-09-2016 11:56 AM Click Here to See the Profile for Easy8Send a Private Message to Easy8Edit/Delete MessageReply w/QuoteDirect Link to This Post
I am sure he did not beef up the suspension at all. Look at v8 archie's site, he has tons of info about this. I run an LT1 in an 86 with the 5 speed transmission. The suspension is stock on my car. When it runs (long story) it runs like a raped ape. I do not recommend the 5 speed on a drag car but a daily driver works fine.
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Report this Post09-09-2016 12:40 PM Click Here to See the Profile for RotrexFieroClick Here to visit RotrexFiero's HomePageSend a Private Message to RotrexFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
I agree with the stock Getrag being able to handle a turbo 2.8. I ran that and a turbo 3.4, and have a 3800sc. I have stomped on it few times and it has not exploded.

I think manual transmissions in general have to be build to handle at least twice the torque of the engine they are bolted. Simply, consider the jolting and shock they take, the spikes in torque would easily shatter gears at the engines rated torque.

Do we have a manufacturers confirmed torque rating for our little Getrag?

If so I need to get a torque gauge on my dash so I don't exceed it!
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Dennis LaGrua
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Report this Post09-09-2016 02:11 PM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
I'll go with the figure of 200ft lbs for a sound good condition Getrag 5 speed trans as that's what one of the GM designers told me years back. Lots of swaps use this box with higher torque and for short bursts/limited WOT use they seem to hold up fine. Clutch drops, or repeated 1/4 mile runs where the torque applied is way over spec will bring a different result.

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