Not a problem buddy

 

Not trying to threadjack but how much of a difference did it make? Staged, you should sell me your Corsa exhaust because I don't think GM used that exhaust. Lol jk

 

The time attack Balt did

 

I picked up 28hp and 17 ft/lbs with the GMR head I bought from John Powell, put me at 263hp/238ft/lbs. Stock cams, kn typhoon, gmpp catback, zzp longtube with high flow cat from autowerks, stage 3 injectors on a m62 with coated rotor on a 2.9 pulley. It ran great all season on track and with the yyz and koni yellows I was shaving 3 to 4 seconds off my lap times at every track I saw this year...compared to last years times. I added a griffin, option b and dual pass to keep iat temps in line, going to single pass for next year as I plan on running a few tracks down south...Rd Atlanta and Barber so wanna make sure heat doesn't become an issue. Long story short, the head was the least expensive bang for the buck given the gains I saw. Adding tvs this winter and engine is done.

 

Thanks Speedbuggy. Did the maximum boost change?

 

Yeah, sorry, I knew I was forgetting something. Prior to head change boost was peaked at 18 or 19psi depending on air quality, saw it hit 20 a couple times on track. Post head swap boost peeked at 15 or 16 psi, on track the highest I saw all season was 17psi. That was when John Heinricy was driving it on track with me in pass seat, so either he is just so good he got more boost out of the car(which he is and did) or the angle I was looking at the gauge made it look like he picked up some boost?

 

Yep, sure did.

Was a 3" version though, but lets not split hairs

Awesome!!

Thank you for adding this. You and I have a similar setup, minus the M62 & stock cams part (although, I might be installing stock cams again).

Are u running pump gas? 93 octane?

I look forward to installing my GMR head even more now.

 

Update:

Sadly, I didn't get to mess with tearing the car apart this weekend.

Had to give the winter beater some much needed attention ie. new brake lines and fuel lines.

This week, I will start tearing her apart for sure.

 

What else do you need to be basicly the time attack cobalt lol

 

Engine wise.... 10:1 pistons & nitrous.

Suspension.... a lot, lol.

 

Yes, I'm running gas, 93.

 

you better not run stock cams

 

Why not, nothing wrong with stock cams.

 

I agree. I have had built a LSJ engine for customers with TVS and a very nice ZZP stage 2 cam set, and the engine made 323 whp on street pump gas. I make with stock cams 320 whp on race gas and 305 whp or street pump gas.

difference is , I have very nice torque band very good on the track and a rev band that starts with peak torque at 4500 ( more peak torque than the stage 2 ZZP and more peak torque than Mr. B shows, and that torque on cams may be a higher peak.) Cross over is about 800 rpm less with the stock cams.

So this makes the car very driveable. Admittedly I run single pass, and I drive like a granny on the street.

The valve train wear on the stage 2 cam set up is pretty hard. On Time Attack, BITD GM tried really hard to get the 272 cams to work, and at the 11th hour with the Time Attack event coming up, and many blown engines in dyno testing, the decision was made to go back to stock cams. LSJ stock cams are very well thought out imho.
There are lots of folks like cams, and I wish them all well with the LSJ. That said,
Speedbuggy, I am with you. And the OP. lol

 

If I can get to 305is on 93 octane I'll be happy with that, nicely balance for the track on 235 tires and still a good daily driver. With the new trans going in next week and the 4.45 final I think I'll be good. Single pass is also in the works before spring.

 

but what about the stg2 cams on race gas?

 

Taylor tuned my car on pump gas then we flipped over to race gas. The first pull I did in 2nd and I definitely wasn't ready for it. I pulled out a 6500 cause I was all over the road

 

thats what Mr. B has just done right?His cams are his, not ZZP stage 2 but his and stage 2 are a lot closer than stock cams.

 

Im thinking of trying mrb cams next season

Replace your timing chain and components Jeff!!!! We have had a few cars lately eat the guide bolts in a bad way on our team

 

Your single pass will be nice. reworking the whole deal. we been scrapping a manifold looking at stuff lol

 

Timing chain will be left alone, but I will be installing new arp timing chain guide bolts. I will re inspect the chain, but when I did my cam install last winter everything looked mint. I also have the upgraded tensioner installed and will be purchasing a new one after for the head install.

Nothing set in stone. The gmr head came with brand new stock cams and I have been tossing around the idea of using them. I also wanted to follow the time attack engine as close as possible, which ran stock cams. Although, I must admit I do love my s1 cams. They have similar torque as stock, but really pull hard to my 7.5k limiter.

 

I would atleast change the black guide if you don't want to do the rest. It does fatigue over time. Don't need that flying apart like it did with Ottawamark haha.

 

John, where does your car make peak power with the stock cams? Also, what do u rev to?

 

Like I said, I will fully inspect everything once I tear her apart. I never half ass anything on my car, but I also do not mess with more than I have to.

 

Oh for sure, I just don't think it's something you are going to physically see though. It's just a piece of plastic that gets a lot of stress on it. That guide and the bolts are the weak points. Preventative maintenence is all haha.