My latest custom project- 4T80E swap in our 1997 Grand Prix UPDATE- Its on the road!

Interested to see how this plays out.
I've got a pretty stout turbo build but the trans is always going to hold me back.

This was done back a couple years ago by Pontiac Jeff @enginered performance

Theres another build thread floating around on Bonneville club I believe.
http://montecarloforum.com/forum/six...65-4t80-31241/

^thats sick thankyou

Jeff had put it on BC before it became GMForums.. it's a twin charged Bonne with 4T80

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Originally Posted by SnowFlake

Interested to see how this plays out.
I've got a pretty stout turbo build but the trans is always going to hold me back.

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yeah no kiddin....we are getting near 8k invested into the trans of the Turbo regal i built for Heavykevy....and its coming back apart for the non tcc groove equipped GMR Armet 100 input shaft (have fun trying to find one of these in the future) along with the converter getting rebuilt for a 3rd time to machine the TCC groove into the turbine hub.
that way we can keep the 1200hp rating of the IS and retain complete TCC functionality with no loss in strength....believe it or not ...this is the cheap fix....way too risky to modify the unobtainium IS which replacment of would cost ~3500$ each shaft and would require a batch of 20 hahahahaNO. the billet Tq converter is farrrr cheaper at 900$. machining the turbine hub is the better option as that portion of the hub is not under any stress and has plenty of meat to cut the groove.

lifes a ***** when your pushing over 600hp/575ftlbs at the wheels with a POS 4t65e

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Originally Posted by 91parkave

This was done back a couple years ago by Pontiac Jeff @enginered performance

Theres another build thread floating around on Bonneville club I believe.
http://montecarloforum.com/forum/six...65-4t80-31241/

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yeah jeff and i have been working with the 80e for years.
jeff controlled his bonnie 80e via a GM diesel 4l80e controller and tunercat.
i figured out how to control it via the stock 65e PCM for the WhippledRiv.

what daves doing with the 80e into a W... has not been done yet (closest i got was a day spent on trial fitment about 5-6 years ago with a 2nd gen W subframe)
the 80e is stupid easy to swap into the B/C/G/H body cars...the W is the *****...otherwise the TR would have one...
it has been stuffed into a 1st gen W so the 2nd gen was possible i just ran into the rack clearance issue

^^^^^ that being said makes me drool at the thought of a 500 plus hp 4t80 bonneville epic sleeper!!!!

what makes it so much easier/more difficult between the chassis styles? is it just the steering rack getting in the way?

The GXP Bonneville came with a 4T80 if that helps you understand fitment. Couple of tweaks and in it would go. I know 2003 SSEi was looking at it and found 65 parts before doing it. The placement of the drivetrain in a W body vs the others and likely the way the mounts are configured is what appears to me as the largest issues.

If I were aiming to build another 3800, it would be a Bonneville. Things are much easier in the bigger bodies.

Yes in a 2000+ H body, there is no modification to the subframe to swap in the -80. All the mounts are factory GM. I was all set to do this, but doing research found that there were issues at the time controlling the shifting patterns and the TCC operation. Plus I found GMR parts for the POS -65.

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Originally Posted by Turbocharged400sbc

yeah no kiddin....we are getting near 8k invested into the trans of the Turbo regal i built for Heavykevy....and its coming back apart for the non tcc groove equipped GMR Armet 100 input shaft (have fun trying to find one of these in the future) along with the converter getting rebuilt for a 3rd time to machine the TCC groove into the turbine hub.
that way we can keep the 1200hp rating of the IS and retain complete TCC functionality with no loss in strength....believe it or not ...this is the cheap fix....way too risky to modify the unobtainium IS which replacment of would cost ~3500$ each shaft and would require a batch of 20 hahahahaNO. the billet Tq converter is farrrr cheaper at 900$. machining the turbine hub is the better option as that portion of the hub is not under any stress and has plenty of meat to cut the groove.

lifes a ***** when your pushing over 600hp/575ftlbs at the wheels with a POS 4t65e

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I'm right there with ya. Haven't done the trans stuff yet (have a lot of parts but nothing installed) but if an 80 proves to handle the power I'd look into swapping to that. Also the clearance in the back of the engine sounds good... I'd really like to be able to run a 3.5" exhaust but the pipe simply won't fit between the engine and brake booster.

Are there upgrades available for the 80? Similar to the 65.. stronger IS, chain, clutches, etc, etc...

Wonder if the 80e would clear w-body frame with oval exhaust tubing instead

oval is going to cost more if it needs to be fabricated why make it complicated just use round and plogs.

Sub'd

Even being a manual diehard, this would be cool to see. Manual bonneville would turn some heads though so I'm still not sure what I plan on for my build. This just made my decision harder. -_-

The 4T80E is the trans that GM should have used in the first place.

Are the gear ratios the same as the '65?

Here are the 4T65E ratios-

1st - 2.92:1
2nd - 1.56:1
3rd - 1.00:1
4th - 0.70:1
Rev - 2.38:1

Here are the 4T80E ratios

1st - 2.96:1
2nd - 1.63:1
3rd - 1.00:1
4th - 0.68:1
Rev - 2.13:1

There are several overall ratios/final drive ratios also that differ from the 4T65E

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Originally Posted by 98GrandPrixIraqVet

^^^^^ that being said makes me drool at the thought of a 500 plus hp 4t80 bonneville epic sleeper!!!!

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id love to do a bonnie, already did a Riv
http://i260.photobucket.com/albums/i...y/hotstuff.jpg

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Originally Posted by SnowFlake

I'm right there with ya. Haven't done the trans stuff yet (have a lot of parts but nothing installed) but if an 80 proves to handle the power I'd look into swapping to that. Also the clearance in the back of the engine sounds good... I'd really like to be able to run a 3.5" exhaust but the pipe simply won't fit between the engine and brake booster.

Are there upgrades available for the 80? Similar to the 65.. stronger IS, chain, clutches, etc, etc...

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nope, but everything is far beefier, hell even the 4th gear clutches are nearly twice the diameter and have 4 times the surface area. the chain is wider than the GMR and with sprocket bearings twice the size of the 65e.
the riv never had a problem going to 200+ kpa in 4th

only thing i ever see having an issue is the IS and its design is simpler than the 65e so making an aftermarket unit would be far cheaper, and even then the IS is larger and thicker walled than the 65e.

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Originally Posted by 2Fast4U

Here are the 4T65E ratios-

1st - 2.92:1
2nd - 1.56:1
3rd - 1.00:1
4th - 0.70:1
Rev - 2.38:1

Here are the 4T80E ratios

1st - 2.96:1
2nd - 1.63:1
3rd - 1.00:1
4th - 0.68:1
Rev - 2.13:1

There are several overall ratios/final drive ratios also that differ from the 4T65E

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yup, the 80e has 3.11, 3.48 and .3.73 FDR

the best part is all the final drive reduction is through the differential planetary the chain is 1to1 only (39/39)

so changing your final drive is just pulling the diff cover and 4 bolts to change the planets/sun

we plan for a 3.73 in the rear and a 3.48 up front on the 442

Cool project Dave

Jeffs car was fun to see at nationals. Ran high 11s I believe.