why can't my motor control a TR 230????
What is your clearance between the outside edge of your spring retainers and the underside of your rockers? The reason I ask is, I too had this problem. I didn't have enough clearance (at least .050") between the retainers and rockers and they were coming in contact at higher rpms. Seemed just like valve float. I had swapped several cams, lifters, pushrods, and springs, but the problem was still there. Once I got the proper clearance between the spring retainers and the bottom of the rockers, my car would rpm like a sum bitch!
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
Thread Starter
On The Tree
Joined: Jan 2004
Posts: 192
Likes: 0
Thanks for the responses guys. I swapped to stock rockers and 7.4 PR this weekend. I'm gonna try another dyno run and see where it gets me. I have a hard time thinking that the cam was installed wrong. The sponsor who put the bottom end together is top knotch. Of course, I did catch the recent post about the SLP DR chain being off 2 deg. I've got that as well. Hmmm...
Yes any of the components could have been manufactured wrong , you don't know unless you check.If the cam was doctored you could rule that out, it also would not be the first time a reputable shop made a mistake.They are only human not perfect.
Improper cam timing will show the results you describe, I would stop throwing parts at it and degree it.
Improper cam timing will show the results you describe, I would stop throwing parts at it and degree it.
Last edited by z-ya; Aug 10, 2004 at 12:09 AM. Reason: spelling
TECH Fanatic
Joined: Jan 2002
Posts: 1,205
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From: harrisburg, pa
DId I miss something? Pro Mag rockers are adjustable...preload must be set at .008-.010" past zero lash cold. I think the pushrod length has something to do with it too. Sorry for jumping in this late but loose incorrect valvetrain will cause this.
Thread Starter
On The Tree
Joined: Jan 2004
Posts: 192
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Basically, stock rockers, Comp rockers, comp-r lifters, stock lifters, 7.4 pr, 7.35 pr, 7.3 pr, crane springs, comp 987, comp 978 in every possible combination produced the same result. It's either the heads or the short block. Place your bets!
Banned
Joined: Sep 2002
Posts: 1,298
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From: So Cal, CA
You sold the heads with the thought there could be something wrong with them, and didnt inform the buyer??
Hope its not the heads because ill be expecting a refund if theres any problems with them
Im having them fully checked out before they are installed.
Hope its not the heads because ill be expecting a refund if theres any problems with them
Im having them fully checked out before they are installed.
Thread Starter
On The Tree
Joined: Jan 2004
Posts: 192
Likes: 0
RELAX. I talked to TEA through this several times. If it were the heads, they'd be down on power in general, not at a specific rpm. These heads made 421 at 6000 rpm with the TR 230. The comment was a slight dig at the short block which is being repaired next week. All signs point to an issue with the lifter bore and oil restriction to the lifters.
If you're that unhappy, send the heads back. I've had three local offers for $400 more since I commited them to you. I'd be happy to increase my profit 50%.
If you're that unhappy, send the heads back. I've had three local offers for $400 more since I commited them to you. I'd be happy to increase my profit 50%.