My LSx Coupe Build

[Jimbo]

Went 7.1@95 in 95* temps. Can't wait to get an antiroll bar and some cooler air. I want 6.9 cam only!

That's running nice. What cam is in it?

[Big A]

weak,.....

You run faster for less?

[Wicked98Snake]

Awesome man, it was nice to meet you at the cruise a few weeks ago. As cool as it was watching you go down the track it was even better to drive behind you as you were driving it home, I'm jealous!

[grove rat]

You run faster for less?

i doubt it

btw, check out that fools new avatar!

[d1tko]

nice ride

[dville_gt]

That's running nice. What cam is in it?

235/240, .648"/.609", 111 LSA, car is really being helm back due to the stock 317 heads, the ports are "okay", similar to ls6 heads, but the combustion chamber is too large, like 72 or 74 cc, so the compression is relatively low (like 10:1). Even just a stock set of ls6 heads would offer a nice jump in compression that a cam like this would really like from what I've been told by TSP. The better option would be l92 heads (which flow 328cfm intake/214cfm exhaust box stock @.600 w/a 4inch bore). I can get some l92s for around 500 but I'd need a new intake manifold (id want a Vic jr w/an acufab carb style tb). That would really pick the car up A LOT but it would cost a lot vs just a set of ls6 heads.

Awesome man, it was nice to meet you at the cruise a few weeks ago. As cool as it was watching you go down the track it was even better to drive behind you as you were driving it home, I'm jealous!

Thanks buddy! I dont own a trailer so this car will be driven to/from the track for the entire time I own it.

nice ride

Thanks, finally getting to race it makes it all worth it. I just really want a 6.9x out of a cam only escalade motor. Anti Roll bar will be next!

[dville_gt]

Got a few minutes to work on the coupe this weekend.

Installed a drive shaft safety loop (probably on borrowed time with a stock 5.0 drive shaft so it is nice to have a little insurance). Used the universal Summit loop and it bolted up great.


Installed a deep B&M th350 pan (+3 qts). I've got a large plate type B&M cooler but the trans was still getting pretty after a pass (230+*). I was running a stock th350 pan so I figure the additional 3qts might help keep the temps from rising as fast.


I also installed a Dakota Digital speedometer pulse generator. This is a pretty neat gadget. It takes the mechanical speedo cable and generates a signal that the PCM can use. I had to get an additional 5" extension cable since the way it is designed it would stick out of the side of the trans about 4" and I simply do not have the room. The best part about this one is that it is "pass-through" so I can still use my mechanical speedometer.


For those interested, the reason I needed the PCM to have a speedo signal is pretty simple (although I didn't think about it till I had the car built):
The car always thinks it is idling, so when I let off the gas and am coasting to a stop the PCM see's that the throttle input is 0% thus it starts trying to get the car to idle. Well, the forward momentum of the car is forcing the engine to spin at a certain rpm so no matter how much the IAC closes the car cannot make it idle. Once I do come to a stop (and the more abruptly I stop the worse it is) the IAC is closed and the car has a very hard time maintaining idle since it has to quickly react to the fact that it actually does need to open the IAC (since now the motor is not being forced to spin). We found a way to get around this through HP Tuners, but it caused the cars idle to hang since it just doesn't try to control the IAC for a given period of time. Thankfully the large stall helps make it driveable, but now that I have a speedo signal it will be nice to get the car tuned correctly.

For the rest of the week I am going to hopefully locate a decent deal on a anti-roll bar, re-wire my alternator (been using the factory escalade alternator DR44G and it actually works as a one wire setup as it is supposed to default to 13.8v if the wires are not hooked up to it, but it seems to be not pumping out enough juice this way so I am going to wire it up the way it is supposed to be and see if it fixes that issue). It is a 145amp alternator so it should be more then sufficient for a race car.

I also want to make a new inlet pipe out of some 4 inch pipe as I am currently running a 3" pvc inlet setup that I am sure is robbing a bit of hp.

Will keep this updated as I go.

[dblack1]

How big is the TBody? If it is a 90mm you are losing some power for sure. How big is the air meter?

[dville_gt]

both are stock. i did semi-port the t/b and used epoxy to smooth it a bit, but otherwise it is the stock 78mm (I believe) and the stock 5-wire MAF. My plan at this point is to get it going as fast as it can as it sits (plus a anti-roll bar). Then at the end of the season if I have the dough:

Buy a set of L92 heads (~$450)
Victor Jr. (#28455) - (~$380)
Accufab 4 Barrel T/B (4B-4150) - (~$500)
Total: $1330

This setup along with a speed density tune would be worth some serious H.P., the L92 heads flow something like 330in/240ex box stock. That along with the vic jr and 4 barrel t/b would yield some insane performance. There is a carb guy with the l92's on a lq4 that runs 9.90's on pump gas in a mustang w/th350 for example.

If the funds are not there then I'll pick up a set of LS6 heads to bump the compression up from (72cc vs 64cc heads) and then maybe add some nitrous.

The 317 heads, stock t/b and maf, 3in pvc intake pipe, and ls6 intake are definitely holding this car back, but I think 6.9x is fully possible if it were just cooler outside.

[Grimpala]

That's a sweet looking setup man!

[dville_gt]

That's a sweet looking setup man!

Thanks! I am really impressed with how docile it is, it drives super straight and going down the track doesn't take much effort at all, point it straight and punch it!

The only hard thing is how much potential the car has that I am leaving on the table with the current heads/intake/throttle body.

If only I had more $$$$

[Junkie]

both are stock. i did semi-port the t/b and used epoxy to smooth it a bit, but otherwise it is the stock 78mm (I believe) and the stock 5-wire MAF. My plan at this point is to get it going as fast as it can as it sits (plus a anti-roll bar). Then at the end of the season if I have the dough:

Buy a set of L92 heads (~$450)
Victor Jr. (#28455) - (~$380)
Accufab 4 Barrel T/B (4B-4150) - (~$500)
Total: $1330

This setup along with a speed density tune would be worth some serious H.P., the L92 heads flow something like 330in/240ex box stock. That along with the vic jr and 4 barrel t/b would yield some insane performance. There is a carb guy with the l92's on a lq4 that runs 9.90's on pump gas in a mustang w/th350 for example.

If the funds are not there then I'll pick up a set of LS6 heads to bump the compression up from (72cc vs 64cc heads) and then maybe add some nitrous.

The 317 heads, stock t/b and maf, 3in pvc intake pipe, and ls6 intake are definitely holding this car back, but I think 6.9x is fully possible if it were just cooler outside.

This setup with a more aggressive cam is going to yield some huge gains! thought about a plate kit?

[dville_gt]

This setup with a more aggressive cam is going to yield some huge gains! thought about a plate kit?

A plate with the l92/Vic or a plate on the ls6 intake and heads? I'd only really consider a bottle if I didn't do the l92 stuff.

[slownbmta]

A plate with the l92/Vic or a plate on the ls6 intake and heads? I'd only really consider a bottle if I didn't do the l92 stuff.

I would do both

[Grimpala]

I would do both

qft