TGP 3.1 differences vs every NA 3.1

[Jeff M]

Well I was hoping to wait and get this all on my web site, most of us are not too concerned as we already have it in our cars, but seems the info is spreading in it's need/interest, so for everyone, here is what I have found so far, please add anything I missed:

 

As for the engine and the McLaren Project, first off Dean is Vice President and Director of Facility Operations, great guy and a very sharp/smart man, we have talked on the phone, and met a few times at car events such as SAE MotorSport Conference and the SEMA Show, Wiley McCoy was there too, great guy who is also very sharp with a real passion for cars, and our/his baby. To repeat some of what was said before, but more so to put all the info in one place, here is what was done to the TGP engine and a little more, some components are used in other vehicle engines as well (see post below for casting numbers).

 

"Select engine components" meaning they were checked when taken from the parts bin for closer tolerances, that includes some of the engine items listed below:

Unique Vin V version of the VIN T Block, part number 10140528, stock VIN T Block is part number 10089656. Block, 20% Nickel content to improve strength, very small amount of tin for same.

(Yet unreleased at that time), head casting 10087511 and its larger, less defined heart shaped combustion chamber, with the deep dished 28cc/ml piston top to achieve the .1 drop in compression ratio to 8.8 (or 8.78 depending on what you read).

Forged Rods, these forged versions are unique to the 1989-90 TGP and TSTE only, part number 10070113, C-1037 Heat Treated Steel Forging, SAE 1050 Air Quenched Rod Caps.

Hardened Crank (Nitrided), Nodular Cast Iron with journal camfer/deep rolled fillets, casting 981 but this one IS unique to the 1989-1990 TGP and TSTE, worked on after starting as a 981 crank! Part number 10110549. Ion Nitrided/hardened depth of .02"-.03" raising surface hardness from 30-35 Rockwell C to 60 Rockwell C.

Mahle Autothermic Hypereutectic Pistons with Reinforcement Bar/Steel Strut to add strength to the top of the piston, 12% Silicone.

Stock 3.1L cam, as used in the 2.8L, 3.1L Vin T and Vin V.

Mellings Iron Body High-Volume Oil Pump.

Engine Oil Cooler as some Monte Z34s had, maybe others, unique water tap to regulate water to turbo, and fittings to plumb it in.

Coolant line take off welded on to provided for turbo water system return.

Oil tap port fitting added to block/metal braided hose for feed line to turbo.

Unique oil pan with turbo oil drain line fitting, and metal hose extension.

Unique Rear Exhaust Manifold to feed with other Exhaust Manifold the Turbo’s Exhaust/Turbine Side, constructed of cast nodular iron.

That damn OEM Crossover Pipe.

Larger 22 lb injectors.

Upgraded Fuel Pump taken from the Vette Parts Bin.

Garrett Water Cooled Turbo, T25 though smallish, at least one of the larger versions of it, for less lag problems though all lag is programmed into the chip, unplug the computer from controlling the boost and tire smoke in less than a second, way too much boost/spin to get a good launch, needs a bigger turbo for lag and traction control!

Boost control solenoid and lines.

ABS Unit Heat Sheild.

Unique Fuel Supply/Return Lines/Engine Bay Area, in front of ABS Unit.

 

 

Tranny setup is unique, larger tranny cooling lines and an aux tranny cooler in fender well.

Hardened Gears and Gear Carrier Set.

Additional Nested Accumulator Springs, other little changes to the tranny, some not listed until it's taken apart for inspection.

1898 rpm Stall Converter, not a High-Stall as the stock turbo is not large enough to warrant it!

Vacuum Line Check Valve/Bleeder at Modulator, Vacuum Line has internal restictor in-line to limit boost pressure and to allow check/bleed to fuction.

 

Larger (Blackstone) 3 Core Radiator that is plumbed for the larger tranny cooling lines.

Largest Electric Cooling Fan from the parts bin at the time, for main engine cooling.

Secondary/smaller cooling fan to assist engine cooling, condenser and intercooler air flow needs.

Blackstone Air-to-Air Intercooler.

 

Some other things but this should get out most of the info people are interested in.

 

Enjoy!

 

Jeff M

[GnatGoSplat]

Yes, the difference is definitely in the heads. I believe the 89 3.1L N/A (which also used the same heads) also produced slightly less HP than the 1990 version. So it makes sense that the 89 3.1L N/A which had the same heads also had the same lowered compression.

 

The first person I recall mentioning the different deck height was Curtis Walker. I don't know if he was certain of it, heard it somewhere, or just guessing. At any rate, I think from that point, we all accepted it as fact, but after comparing casting numbers, I don't think it's true.

 

I don't think that post by "dizacav" is accurate either.

 

The TGP engine has things which are "tightened" a bit more than the 3.1 vin T, the vin V engines have a bit larger lift when it comes to the crankshaft and things like that, but nothing major.

 

A bit larger lift on the ("crankshaft"? He meant Camshaft-jm), and I think it has been established a long time ago that the same camshaft is used on the TGP and NA (jm). I think the problem is the person he talked to is a "Vice President and Director of Facility Operations". That sounds like an upper-level management position. I don't know about most workplaces, but around here, upper-level management's main job task is politics - meetings, employee motivational activities, making sure everyone is performing their duties efficiently, etc. Upper-level management is usually rather disconnected from the actual work being performed by lower-level employees. I would not imagine that any VP or Director will have the first-hand knowledge to provide specific technical details with any degree of accuracy.

[Jeff M]

Some more info: First small stuff, Mr. McCoy was President at McLaren back when the TGP and TSTE were done, McCoy drove a White TSTE for several years and liked it, but kept it mainly for a test bed since they were the ones that EPA Certified it’s Emissions Compliancy. It was 15 years ago when this project was done at McLaren, seems Dean might not be remembering all the fine details, not that he should, even Mr. McCoy who I know was involved could only remember so much after all this time.

 

VIN T Engines used from 1988-1990 stock head casting numbers: 10048651, 10048696, 14089834

VIN T W/O/SEFI Engines used from 1991-1994 stock head casting number: 10087511

VIN T W/SEFI Engines used from 1993-1994 stock head casting number: 10087511

VIN M Enhanced Engines used from 1993-1995 D-Port stock head casting number: 10154743

VIN M Enhanced Engines used from 1996-1999 D-Port stock head casting number: 24503769

VIN J Special Emissions Spec used in 1999-? stock head casting number: 102181170

 

VIN V Engine (cast with a “T†on the block) used in 1989-1990 TGP and TSTE had stock head casting number: 10087511

 

The stock/NA VIN T engines of 1988-1990 used the 3 different casting heads that all had the smaller designed/more pronounced heart shaped combustion chamber, which was replaced with the 10087511 in 1991-1994 with its more open/less defined heart shaped combustion chamber, then back again for VIN M 1993-1995 and VIN M 1996-1999 with the smaller chamber and more pronounced heart shaped combustion chamber (shuffling the deck a lot!). Changing the piston’s dish volume allowed working with these different heads/combustion chamber volumes, and the 2 different head gasket thicknesses of .040†and .060†to achieve design compression rations for the engine

 

So, for the 1989-1990 TGP and TSTE, they used the yet unreleased at that time, head casting 10087511 and its larger, less defined heart shaped combustion chamber, with the deep dished 28cc/ml (what Mahle quoted me and I cc’d out of it too) piston top to achieve the .1 drop in compression ratio to 8.8 (or 8.78 depending on what you read).

 

Anyone else find more info please let me know. Also remember over the years past work done to your TGP may have changed some things/heads, seems pretty easy to mix things up here if the mechanic did not have all the info he needed. Last, do not use the FelPro Performance Head Gasket 1029, too thin and will raise the compression ratio!

 

Added: Upper and Lower Intakes for 1989 and 1990 TGP and 1990 TSTE.

 

1989 TGP Upper Intake Casting Number 10110556

1989 TGP Lower Intake Casting Number 10070110

1990 TGP and TSTE Upper Intake Casting Number 10131046

1990 TGP and TSTE Lower Intake Casting Number 10110432 and 10137026

 

1989's had PCV Line into lower intake, 1990 had PCV into Upper Intake, BUT it may have been a mid-year production change in 1989 so if someone finds thier 1989 TGP has the 1990 setup, please let us know!!

 

Jeff M

[GnatGoSplat]

Jeff,

My parts catalog shows the following application for heads:

 

88-89 2.8W 10048649

89 3.1T 10087509

89-90 3.1V 10087509

90-93 3.1T 10048649

 

This is the same in my parts catalogs dated Feb 92 and also May 98.

This doesn't correspond to your head casting chart, as the GM parts catalogs show that only the 89 3.1T (the one with vacuum EGR) is the only other engine to share the same heads as the 3.1V.

[Jeff M]

Jeff,

My parts catalog shows the following application for heads:

 

88-89 2.8W 10048649

89 3.1T 10087509

89-90 3.1V 10087509

90-93 3.1T 10048649

 

This is the same in my parts catalogs dated Feb 92 and also May 98.

This doesn't correspond to your head casting chart, as the GM parts catalogs show that only the 89 3.1T (the one with vacuum EGR) is the only other engine to share the same heads as the 3.1V.

 

Yep , I have a bunch of parts books too and find they are misleading at times, specially since the heads off of the last several TGPs I worked on where the 10087511. Since you listed these numbers here, does your book show casting numbers along with part numbers, which are these? What I would really like (aside from what you can find) is the casting numbers off the 1989 since I just don't see anything but 1990s here, mainly to confirm the heads but also the lower intake since it has the PCV line into it, and 1990 has it into the upper intake.

 

Jeff M

[maddux31]

I have had two 90's and currently have an 89. My P & I catalog says part#10087509. My 90's all had casting #10087511. I'm looking at my 89 and it has 10087511 also. Must be some GM engineering on the different #'s. Dale M. Omaha, NE.

[Jeff M]

I have had two 90's and currently have an 89. My P & I catalog says part#10087509. My 90's all had casting #10087511. I'm looking at my 89 and it has 10087511 also. Must be some GM engineering on the different #'s. Dale M. Omaha, NE.

 

Thanks a lot dude Chris already said this but to clear the air here, casting numbers are different than part numbers, and that is why I am only going to refer to casting numbers. Also most people looking into working with any of these heads will only see casting numbers unless they are buying new (?), AND GM is known to change casting numbers but NOT part numbers for the exact same part, and vise-versa, so that makes it harder to know what you are working with, so casting numbers are best though those can bite you in the butt like the crank above being a 981 but not the same 981 as a NA, challenge is your GM parts man has to be pretty good (or make the effort) to help you with casting numbers, for that you need to know the aftermarket specifically the engine rebuilders (where I got my data). These guys see literally 100s of thousands of engines and note where they came from, what they are like, will work with, how to modify to work with others, durability, work to fix, etc, a real challenge but they to me proof out what "was" made, and how it looks, compares and works with other applications etc. I know that the heads for the TGP and the 1991 on ones were made in Mexico (its labeled on there) but the others that are not labeled and have an insignia are made in France, and were better castings/more consistent in dimensions etc, but from those rebuilders, state a low 3-4% junk rate on the aluminum ones, but 10% on the iron ones. Our turbos were also made in France.

 

Would you buy chance have seen the casting number on your lower intake, hell if by chance the upper intake on the 1989 since it too is different since there is no PCV hole under it?

 

Thanks again!!!

 

Jeff M

[maddux31]

My upper intake on the 89 is casting #10110556 and the lower intake on the 89 is casting #10070110. Lower intake says mexico but upper intake does not say manufacture site. Don't know of the #'s off the 90's but I had receipts for head work off one of my 90's. And again the part #'s in the P & I catalog are different than the cast #'s. Jeff, thanks again for all the info on the rebuild, should be running tomorrow.

[Jeff M]

My upper intake on the 89 is casting #10110556 and the lower intake on the 89 is casting #10070110. Lower intake says mexico but upper intake does not say manufacture site. Don't know of the #'s off the 90's but I had receipts for head work off one of my 90's. And again the part #'s in the P & I catalog are different than the cast #'s. Jeff, thanks again for all the info on the rebuild, should be running tomorrow.

 

Thanks again!!! Check 2 lower and 2 uppers I had from 1990s and got 10110432 for lower and 10131046 for upper, added them above. :oops: Shit :oops: you are one of the many emails and PMs I have to do, many of those priorities like yours, sorry for messing around here having fun, will get to you before (I hope) you start your assembly!!!!

 

Jeff M

[Guest TurboSedan]

after reading this thread i decided to go check my #'s...

 

my TSTE 'V' engine (pulled from local j/y TSTE):

 

heads - #10087511

lower intake #10137026 (double diamond 'IF' insignia, not Mexican)

upper intake #10131046

 

i also have a box full of other misc. TGP parts. this upper intake has the breather tube going to the upper intake like my '90 TSTE stuff does, so i'll assume it's '90 also. i bought these from eclipse5302 fwiw:

 

lower intake - #10110432 (Mexican)

upper intake - #10131046

 

the stock '91 heads on the NA 3.1 in my Cutlass have casting #10048696

 

joshua

[Guest TurboSedan]

would definately be a good sticky!

[Jeff M]

Well, it’s now a Sticky. Might not be as long of a Topic as it once was but since its an Info-Topic Sticky now, I took out anything that was not “info†for the Topic, making it easier to get to the information needed. As always, if anyone finds anything else to add let me know!!

 

Jeff M