Thinking of going wild 3.4, 3.5, or 3.9???

[Shifter23]

I am posting here and on W-Body forums to collect advice on the ideas of doing a modern transplant in a tired TGP.  Me and NTRCOOL have been toying with this for a while so any input would be appreciated.  The TGP to be used would be one that is already incomplete and would be getting "gutted" for racing.  All parts removed will be shelved to preserve the 10 TGP, and TSTEs between us.  Stock turbo is not a must either but since we would be building from 2nd hand parts the turbo ideas would be a limited situation too.  3.4 and later 3.5 engines are easily found but just curious on thoughts of the newer 3.9 powerplant too.  THis is an experiment in the making and probably will be a nasty road ahead but either way we are pondering it seriously.

[90grandprixstet]

personally i would pick a 3.4 due to the fact there cheap, easy to obtain, and alot of people have swapped them, with the 3.5 u run into a few issues especially if you get the VVT one...

[mfewtrail]

Really depends on how much work you're willing to do and what kind of power you're after. The stock engine can make plenty of power with an upgraded turbo. The only way I would swap out my 3.1 would be if I blew it up. I would then go with a 3500(LX9), make custom manifolds, x-over, etc. and probably keep it OBD-I running the TGP code. The 3500 has right around 200hp naturally aspirated....so it's already got 60hp more than our original base engine. The 3500 swap without a turbo would be on par with a stock TGP. A good sized turbo on a stockish 3500 could make as much power as most of us would ever want in a FWD car. If you can weld/fabricate things on your own, everything could be done relatively cheap. The biggest expense would be the turbo & a nice intercooler to go along with it. I can find 3500's in my area with 50,000-75,000 miles on them for as low as $200 for what it's worth. They go for cheaper than the old ass 3.1 MPFI engines in my area due to lack of demand.

[GPChief]

L67/L32 & 4T65E FTW...just turbo that.

[Jonpro03]

L67/L32 & 4T65E FTW...just turbo that.

BOOOOOO!!!

Really depends on how much work you're willing to do and what kind of power you're after. The stock engine can make plenty of power with an upgraded turbo. The only way I would swap out my 3.1 would be if I blew it up. I would then go with a 3500(LX9), make custom manifolds, x-over, etc. and probably keep it OBD-I running the TGP code. The 3500 has right around 200hp naturally aspirated....so it's already got 60hp more than our original base engine. The 3500 swap without a turbo would be on par with a stock TGP. A good sized turbo on a stockish 3500 could make as much power as most of us would ever want in a FWD car. If you can weld/fabricate things on your own, everything could be done relatively cheap. The biggest expense would be the turbo & a nice intercooler to go along with it. I can find 3500's in my area with 50,000-75,000 miles on them for as low as $200 for what it's worth. They go for cheaper than the old ass 3.1 MPFI engines in my area due to lack of demand.

YAAAAA!!!!!

I plan on turboing a 3500 in my tgp exactly as ^^^ described

[90grandprixstet]

yea lets try and keep the 90* v6's out of our turbo GP's

[Shifter23]

Me and Matt a.k.a. NTRCOOL want to do a TGP so yeah no 90* engines there is tons of support but at the car shows we get tired of hearing hey dude just put a 3.8 supercharged in it.  We could turbo one but we have a project that is going that way and that is via. a 87 Buick Lesabre T-type that will be made the way GM should have done it.  Some argue and say it is FWD well if you want RWD then get a Regal T-type or GN.  So good call GP Chief but we are going the long way lol.  Any other input is appreciated.

[TGed]

3900, there is no replacement for displacement.

[Jonpro03]

3900, there is no replacement for displacement.

3900 = more work than its worth. I will be very surprised if anybody gets a 3900 to run on tgp code

[TGed]

3900 = more work than its worth. I will be very surprised if anybody gets a 3900 to run on tgp code

I never said it would be easy. lolololol

Megasquirt and change up the valve train system = work.

[Jonpro03]

Change the valvetrain = necessary
Megasquirt doesn't have the capacity to run a VVT system... Also you have to worry about the intake because it has dual intake runners. And the throttle because its electronic.

[Shifter23]

Good info. So far it looks like a 3400/3500 hybrid is the most logical choice.  I am a stickler about displacement, but looks like the 3.5 might be the choice.  Is there anything that might be a "snag" with this swap?  I understand the usual stuff but gotta ask just in case it never hurts.

[Jonpro03]

Im planning the same swap... hope to pick up my 3500 next week. Engines around here don't come with accessories. I plan on swapping all of the accessories over if I can. I know that the crank sensor won't work and it needs to be swapped or an external crank sensor installed. Ill try to find the post from the guy on 60degreev6.com who's already done this swap.

[Jonpro03]

Here's what I was thinking of... I guess it wasn't a tgp.
http://60degreev6.com/forum/f96/3500-swap-questions-t36647
From what I understand... You need to worry about the coolant temp sensor. It was moved to the rear head so you need to extend the wires or buy the adapter from wottech http://wot-tech.com/shop/all/cts-extension/prod_254.html

Theres a problem with the crank sensor. This is from pg 3 of that post

OBD-I uses:
7X crank sensor. (Reads from 7 slots in crankshaft)

OBD-1.5 & OBD-II uses:
7X crank sensor. (Reads from 7 slots in crankshaft)
24X crank sensor (Reads from 24 notches in back of dampener)
cam sensor (Reads from a notched ring on camshaft)

LX9 3500 uses:
56X crank sensor. (Reads from 56 notches on crankshaft)
cam sensor (Reads from a notched ring on camshaft)

LZ series engines use:
60-2 (60 teeth with 2 missing) crank sensor
cam sensor

OBD-I cars do not require the use of the 24X crank sensor there is no need to change the front cover and dampener. Superdave is running this setup.

Your car has OBD-II and requires 7X & 24X crank sensor inputs. The external trigger from the store takes care of the 7X sensor. Using the front cover and dampener from your current engine will give you the 24X sensor since the 24X sensor is mounted to the front cover behind the dampener.

Hopefully that makes it a little clearer.

Changing the front cover is pretty easy. It can be done without dropping the oil pan if you want. Just pull the dampener and remove the front cover. For a good seal, be sure to use a little silicone in the corners where the pan and block come together before putting the front cover on. Also, make sure to use the new front seal for the dampener since it should come in the gasket kit.

Unfortunately I don't know what the tgp ecm needs. I know it needs a 7x crank signal but don't know where to get it on a 3500. Hopefully somebody else can chime in here. If it requires an external crank trigger... here's the link
http://wot-tech.com/shop/all/external-crank-trigger/prod_42.html

You have to use the 3100 fuel rail and either grind the UIM or adapt the FPR to fit... OR use a 31/3400 UIM
The TGP exhaust manifolds will be really small on the 3500 but will work with some grinding. I plan on doing that.
I don't know about the EGR but I doubt it would work. So get a block plate:
http://wot-tech.com/shop/all/2000-aluminum-egr-delete-kit/prod_166.html
I use this on my LG8 in the 96 prix.

Throttle body: The 3500 uses an electronic throttle. I plan on using a 56mm from a 3400 with this
http://wot-tech.com/shop/all/3500-plenum-tb-adapter/prod_30.html

I hope this gets you started...

[GhrarhG]

You have to use the external crank sensor setup from WOT on the 3500 to get the 7x pulse which the tgp ecm needs.

If they mahe another run of tb adapters soon, you can use it to bolt a cable driven 65mm tb from the 3.5 dohc motors