GM Racing Exhaust Ported Cylinder Head
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Joined: 12-30-07
Posts: 14,079
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From: NEPA
True true.... Everything will be checked and inspected before I reassemble. There are things to look for on guides that may lead to replacement. I'm interested to see if there has been any increased wear since I installed the cams.
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Joined: 01-09-10
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From: Aurora, IL
New Member
Joined: 01-09-10
Posts: 117
Likes: 0
From: Aurora, IL
I was just doing preventative maintaince on the timing system at 60, 000 miles, found the cracked guide and then stumbled on the the GMR head when talking with John. Been very happy with my luck it's worked out well, also put the Powel pcv upgrade on along with the head and that's kept things nice and clean intakewise, idle surge improved. it still acts up some, but I think that's just the o2 sensor being lazy in the k&n cai housing.
I was just doing preventative maintaince on the timing system at 60, 000 miles, found the cracked guide and then stumbled on the the GMR head when talking with John. Been very happy with my luck it's worked out well, also put the Powel pcv upgrade on along with the head and that's kept things nice and clean intakewise, idle surge improved. it still acts up some, but I think that's just the o2 sensor being lazy in the k&n cai housing.
I have the same amount of miles as you, but have never inspected anything timing related. Heck, I have never even had the cam cover off. Was your guide starting to crack, or already cracked in half. Usually whenever there is chain that has developed slack or if the guides are worn its noticeable, and you can hear an audible slapping from the chain. Did you hear any noises prior to doing maintenance?
Thread Starter
Joined: 12-30-07
Posts: 14,079
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From: NEPA
All my guides and timing components were mint at 48k miles when I installed my cams and valve springs last winter.
I put about 5k on the car this spring/summer/fall and will inspect it all again when I begin the gmr head install.
I put about 5k on the car this spring/summer/fall and will inspect it all again when I begin the gmr head install.
stock cams are decent cams but there are better choices
I can say this my car is 100% easier to drive then a stock cammed car on the street it has a lot more power(even more then the zzp stg2 cams) every where and the car is really smooth
the only way you will even come close is to switch the fuel source to e85 and realy lean on it or put cams in it or buy a tvs
I did a mix its not straight race fuel I decided to stop where its at in favor of a fuel change e85 is easier on the engine then race fuel and enlarges the tuning window by 10 fold
they are better then zzp 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
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
they are better then zzp cams
I love the posts saying my cams are better than his cams etc.
so far on engine on your cams has produced around 330/250 which is roughly 3% more than a zzp stage 2 we did here on pump gas. different dynos different days, I would say its a wash.
good luck with developing your build; it looks promising, once you figure out how to deal with the maf scaling. Arm can help you I expect.
so far on engine on your cams has produced around 330/250 which is roughly 3% more than a zzp stage 2 we did here on pump gas. different dynos different days, I would say its a wash.
good luck with developing your build; it looks promising, once you figure out how to deal with the maf scaling. Arm can help you I expect.
Thread Starter
Joined: 12-30-07
Posts: 14,079
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From: NEPA
Woahhhh hey guys.... no need to get touchy about cams in my thread 
Powell, where does your car make peak power with the stock cams?
Where did Time Attack make peak power with the stock cams (if you can remember)?
I have the Time Attack blower, and assume she can produce power past 7k on the stock cams with the GMR ported head. On the stock head, power peaked around 6800 rpm.
Powell, where does your car make peak power with the stock cams?
Where did Time Attack make peak power with the stock cams (if you can remember)?
I have the Time Attack blower, and assume she can produce power past 7k on the stock cams with the GMR ported head. On the stock head, power peaked around 6800 rpm.
Last edited by Staged07SS; Nov 13, 2013 at 01:46 PM.
I love the posts saying my cams are better than his cams etc.
so far on engine on your cams has produced around 330/250 which is roughly 3% more than a zzp stage 2 we did here on pump gas. different dynos different days, I would say its a wash.
good luck with developing your build; it looks promising, once you figure out how to deal with the maf scaling. Arm can help you I expect.
so far on engine on your cams has produced around 330/250 which is roughly 3% more than a zzp stage 2 we did here on pump gas. different dynos different days, I would say its a wash.
good luck with developing your build; it looks promising, once you figure out how to deal with the maf scaling. Arm can help you I expect.
Woahhhh hey guys.... no need to get touchy about cams in my thread
Powell, where does your car make peak power with the stock cams?
Where did Time Attack make peak power with the stock cams (if you can remember)?
I have the Time Attack blower, and assume she can produce power past 7k on the stock cams with the GMR ported head. On the stock head, power peaked around 6800 rpm.
Powell, where does your car make peak power with the stock cams?
Where did Time Attack make peak power with the stock cams (if you can remember)?
I have the Time Attack blower, and assume she can produce power past 7k on the stock cams with the GMR ported head. On the stock head, power peaked around 6800 rpm.
Last edited by mrbelvedere; Nov 13, 2013 at 01:59 PM. Reason: Automerged Doublepost
Just for info, the Harrop TVS keeps pulling past 7k to 8k, and the power curve doesnt drop. And thats with stock cams..... That said, its just not realistic to rev that high, it costs too much in upkeep.
OP I will go look for dyno sheets this weekend. Too much to do right now...
OP I will go look for dyno sheets this weekend. Too much to do right now...
Last edited by Powell Race Parts; Nov 13, 2013 at 05:57 PM. Reason: Automerged Doublepost
Thread Starter
Joined: 12-30-07
Posts: 14,079
Likes: 197
From: NEPA
Just for info, the Harrop TVS keeps pulling past 7k to 8k, and the power curve doesnt drop. And thats with stock cams..... That said, its just not realistic to rev that high, it costs too much in upkeep.
OP I will go look for dyno sheets this weekend. Too much to do right now...
OP I will go look for dyno sheets this weekend. Too much to do right now...
Just for info, the Harrop TVS keeps pulling past 7k to 8k, and the power curve doesnt drop. And thats with stock cams..... That said, its just not realistic to rev that high, it costs too much in upkeep.
OP I will go look for dyno sheets this weekend. Too much to do right now...
OP I will go look for dyno sheets this weekend. Too much to do right now...
Woahhhh hey guys.... no need to get touchy about cams in my thread
Powell, where does your car make peak power with the stock cams?
Where did Time Attack make peak power with the stock cams (if you can remember)?
I have the Time Attack blower, and assume she can produce power past 7k on the stock cams with the GMR ported head. On the stock head, power peaked around 6800 rpm.
Powell, where does your car make peak power with the stock cams?
Where did Time Attack make peak power with the stock cams (if you can remember)?
I have the Time Attack blower, and assume she can produce power past 7k on the stock cams with the GMR ported head. On the stock head, power peaked around 6800 rpm.
the time attack ran to 7800 iirc on the money lap. But Heinricy drove to win, and he would always round out to the higher whole number
8k lol
Thread Starter
Joined: 12-30-07
Posts: 14,079
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From: NEPA
How I wish that car was still around today.
Joined: 05-18-11
Posts: 39,564
Likes: 87
From: West Chicago, IL
i never could find much info/pictures/footage on that car besides in the build book and people.mentioning it as the god of all cobalts. anyone got a lead on this thing? 
Joined: 05-18-11
Posts: 39,564
Likes: 87
From: West Chicago, IL
i het!
john, a request from me that im sure.others would piggyback on: make a thread all about that car.
ok, /thread tangent.
car still going under the knife this next week?
john, a request from me that im sure.others would piggyback on: make a thread all about that car.
ok, /thread tangent.
car still going under the knife this next week?
Thread Starter
Joined: 12-30-07
Posts: 14,079
Likes: 197
From: NEPA
Might start tomorrow afternoon after work
Don't worry, it's heart will live on in my car, haha.
Here's a nice article on it: http://www.grand-am.com/News/GA_News...-speed-tv.aspx
Here's the only video I've seen of the actual T/A car:
Last edited by Staged07SS; Nov 14, 2013 at 09:17 AM.
Thread Starter
Joined: 12-30-07
Posts: 14,079
Likes: 197
From: NEPA
Added a new part to the list.
GUIDE 13104978
Speedbuggy & Bluelightning got me thinking about changing the plastic chain guide. It's only a $14 part, why not?
I will of course inspect the other chain guides for wear, as well as all the timing components, but since it is nearly impossible to spot a hairline crack in plastic, I figured I better change it.
GUIDE 13104978
Speedbuggy & Bluelightning got me thinking about changing the plastic chain guide. It's only a $14 part, why not?
I will of course inspect the other chain guides for wear, as well as all the timing components, but since it is nearly impossible to spot a hairline crack in plastic, I figured I better change it.
Last edited by Staged07SS; Nov 15, 2013 at 11:23 AM.
