Mach 5's TGP 3.1 big numbers build

[Mach 5]

so had some issues with the crankshaft again so ive decided to consolidate all my projects and work with what I got. Please see for sale thread for the many parts that I have for sale that will be funding to finish this car. The 1990 McLaren shell (Racer X) is also up for grabs.. That being said I will continue on my quest to attempt to build bigger and finish what I started. A 7xx HP engine.. Interior will also be restored along with the exterior.



The last piece I need to make it work is a Crower billet crankshaft. Then I can finish the motor and work on the interior/ exterior. I know much of everything sounds confusing as Im all over the place with my projects but this is why Im starting semi-fresh. So I can ensure everything will get done and Im hoping this car by the time of the Ohio meet.



I will need to ask.. Does anyone have an A/C setup for sale?? all the lines and everything? and also Im looking for at least 1 seat mainly the drivers power seat in gray leather as its frame is broken and torn.. also need a sunroof module





build



1989 Pontiac Grand Prix SE Turbo



-GTX3582R

-RRRM Headers and Downpipe

-Crower Billet Crankshaft

-Program Billet Main caps

-Carillo H Beam Rods

-JE Pistons w/ chrome moly rings

-Tilton Twin disc Clutch unsprung

-Getrag 284

-The Driveshaft Shop axles

-Koni Shocks

-Birchmount rear Leaf

-Intrax Front Springs

-dual 3 inch Dynomax Ultraflow mufflers

-exhaust cutouts which will be operated via Hobbs Switchs

-TGP Wheels

-96 brake conversion

-3xxx race ported heads and intake

-65mm billet throttle body

-water/ air intercooler

- WOTTECH Race Roller Cam

-Crane link bar roller hydraulic lifters

-GM roller rockers

-Personal Steering wheel

-Racetronix dual walbro fuel pumps

-Griffen aluminum radiator

-BXX Fab Tubular Heim Joint Rear Arms Trailing and Lateral

[Guest]

hitting 7xx hp with that turbo is going to be tough to do. You will need to be between 21-28 lbs of boost to hit the 70 lb/min required to even get to 700 bhp. You might want to think something larger than a 62mm wheel to hit 7xx hp.

Not sure what displacement you are looking to have, but the lz4 crank is a steel crank. You can get them cheap. It is a 76mm stroke. Mate it with a lx9 block and you will have a 3.1 on a stock bore, and a 3.2 on a .030 overbore. The reason I am saying to go with the lz4 crank is because the lz9 crank will definately require notching of the block near the oil pan to clear the larger rods. Not sure if the lz4 crank will but if so it will be less.

Or if you get an lx9 engine from a junkyard, most likely you will get one that has a steel crank from the factory, which means you can use the 2.0 big end rods and WOT tech sells forged versions. Thats a 3.31 stroke, so you will be at 3.5 liters then if you were to use the lx9 block.

if using a lz4 crank, you of course will need to use or find the 2.25 big end rod which isn't hard to find but you are looking for forged rods anyways so you can find them to fit the lz4 crank. Like I said its a steel crank and its cheap from jyards

A single walbro 450 will support your hp goal as well. No need for two pumps

[Xnke]

Will be a cakewalk with a slightly bigger turbo and a 3500 engine.

Send the heads/intake out to Slover's Porting Service and tell them it's a full-race car and you'll be able to make the power. They may ask you for three heads to return two, however, and it will cost what it costs in the end.

[Mach 5]

Ive snapped 2 3500 cranks already. The turbo is most efficient in that boost level. Im looking for 7xx which would be crank horsepower. should be able to hit it no problem I believe. but we shall see. I will post pictures of the build progress this week sometime maybe even tonight if I get a chance

[Guest]

Ive snapped 2 3500 cranks already. The turbo is most efficient in that boost level. Im looking for 7xx which would be crank horsepower. should be able to hit it no problem I believe. but we shall see. I will post pictures of the build progress this week sometime maybe even tonight if I get a chance

I must have missed your dyno numbers somewhere to have broken two cranks. Vids? Can we assume they were the steel ones? where did the cranks break?

$3300 for a crower crank. must be nice to have deep pockets.

That turbo is not most efficient at 70lb min. You are at your choke point which is near 65% eff or less. Its actually prob closer to 60% eff Most eff for that turbo is in the 2-2.5 bar area and around 50 lb/min of airflow. Thats about 78% eff.

A gtx4202 is closer to max eff at 2.5 bar and 70lb min than your x35r

[Mach 5]

im rarely ever on here. usually on w-body. LG5 3.1 w/ a 3500 crank, roller cam, and a gt3076r.. journals were cut down to fit h beams. the second crank just broke the other day..ugg the first crank had a relatively small radius the second one had an 1/8" radius and we chamfered the rod and bearing to suit..

the gtx3582r is rated for 750hp with the t4 twin scroll setup 1.06 a/r I will be using..

hey man I just work like everyone else. I figured I would share my build. I respect everyones knowledge, thoughts and opinions.

-Jarek


video- https://www.youtube.com/watch?v=TUa6wpQcW6A

https://www.youtube.com/watch?v=tSCBC2_ERg4

https://www.youtube.com/watch?v=8tLw8c02Br4

[Guest]

How much was cut from the cranks? I would look at using larger journal rods before cutting down a crank, to keep the strength. There have been reports of people making that much power and more on stock crank LX9s without issue. I know of an LZ9 making somewhere around 125HP more without any reported crank issues.

[Mach 5]

it was cut down to a 2" journal size. I would have rather had 2.100 journals but I already had the h beams and I bent the 981 stock LG5 crank so at the time that was my best option. The shop I deal with and myself called around to try getting it hardened and a few companies said it wasn't worth the cost. I don't have much history on here but I have a 1990 McLaren and an 89 gp se. I was building this motor for the 90 tgp but due to this crank problem and my funds running lower than id like Im cutting my losses and moving on all in to this project which will go in to the 1989 TGP SE. That car mans a lot to me as it has been in the family fr a very long time. It was the car that picked me up form the hospital when I was born as well as my first car. My mother passed away in 2012 and this being her car many memories road trips etc.. so Im keeping the 89 and selling the 90 to hopefully my friend unless that idea backfires then Ill just keep it around.. Anyways enough with my tangent...


If Im home from work at a decent time tonight I will post pictures of my progress. The block will be going to the machine shop as soon as the other motor is out..

and for reference since Im sure many will be confused...

Mach 5- 1989 Pontiac Grand Prix Turbo SE (white)
Racer X- 1990 McLaren Pontiac Turbo Grand Prix (red)


the engine that blew in the Mach 5 was originally in the Racer X which decided to switch so I could build the motor that Im building for the Mach 5 now.. since as of last week my second crank broke..


-Jarek

[Guest]

modifying the crank to fit your rods is not the correct way to do things. Buy the rods to fit your crank. I could have sworn the lx9 crank had 2.0 inch rod journals to begin with so why was machining necessary? Im confused.

I made 370 whp and 460 tq using a cast 3.1 crank. Thats over 400 crank hp and 500 tq. The steel one should do 500hp easy without a sweat.

Yes a 3582 can push 75 lb/min but I was merely correcting you when you said its at max efficiency there. its not. It can make that power but it is maxed out and to make 750ish crank hp, will depend more on overall efficiency of your engine, and the aggressiveness of the tune.

lz4 crank can be turned down to 2.1

[Guest]

The LX9 has larger journals than 2.0". I believe they are 2.1", I'll have to measure one of my LX9 cranks to know for sure.

[Mach 5]

Its a 2.250" journal.

[Mach 5]

I never dynod it on the 23psi I used to run, only at 16psi when it had headers and it made 321hp 408tq @ 17psi with ported TGP logs. the 981 cranks actually twisted and bent for me quite a few times before I finally had the 3500 crank machined to fit the block. The journals were always ok on the 3500 crank just that it broke at the radius. I know it wasn't right but at the time I didn't have all the funds to swap rods and such. It worked for 16k miles so whatever Im not happy but it was a lesson learned.. Either way this thread isn't about that engine.. Its about the latest project. I already have most of the parts and Im all about building a gen 2 3.1 block since that's what my car came with.

[Mach 5]

some pix..

[Xnke]

The large-journal cranks are 2.25", shared with the 4.3l engine.

Sent from my KYOCERA-E6560 using Tapatalk

[Mach 5]

I picked this specific turbo for its overall powerband as well as its ability to perform at higher boost levels. No reason to go to a larger turbo just to make peak numbers. Ill be pulling the other engine out this week and then the project will officially start.

hhmm I didn't know the 4.3 had the same journal size. prob the same rod length too right??