TRex results with stock heads
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Joined: May 2002
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From: Fremont, CA
Originally Posted by Rick@Synergy
Very little preload is required for Comp R lifters.
Rick
Rick
Originally Posted by RTCamaroSS
4-10 thousandths or so, yes. i beleive they might be overloaded.. but when we did our calculations, it came out to 6 thousandths or so. which should be perfect. dyno graph looked weird above 6700 though, just kinda falls off. may be an air flow problem as well. gunna try a few things and see whats up.. ill try to get the graph scanned and posted soon.
I would actually just put a quarter turn on the rocker into the lifter to give it 10-25 thou. Thats your best bet. You need some on the lifter, too little and you run into problems.
By the way, how can you calculate preload? All you need is a dial gauge.
Rick
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From: NC, Charlotte / SC, RockHill
1 7/8's headers
but it seems to die after 6700 or so
I thought that a 1.7 rockers r not recomanded!!!!
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Joined: Apr 2003
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From: Miami
Originally Posted by prostock_bigblock
I think switching to 1 7/8 is making your car dying after 6700rpm , exactly the same i did after intalling the X3 .
I thought that a 1.7 rockers r not recomanded!!!!
I thought that a 1.7 rockers r not recomanded!!!!
i can tell you what i know from dozens of dyno runs on different cars, you have to have very very strong vavlesprings to make it carry out to where mine does, on jasons car it peaked earlier than mine and didnt carry out as well, after seeing what his did, we used shims to get more seat pressure on the springs and measured them on the spring compressor to get as much as possible without getting coil bind at max lift. mine carried to 6700-6800 and flatlined past 7000 before droping off. i pulled 442 with the lsx manifold going through all my hp robbing drivetrain 12 bolt, steep gears and on 28'' slicks, probably would have gone high 450's and 405rwtq or so with a stock rear and tires. im hoping to get high 450's with the new changes, same drivetrain stock rockers work best and im on stock lifters also. 
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From: Fremont, CA
Originally Posted by SMOKIN01TA
i can tell you what i know from dozens of dyno runs on different cars, you have to have very very strong vavlesprings to make it carry out to where mine does, on jasons car it peaked earlier than mine and didnt carry out as well, after seeing what his did, we used shims to get more seat pressure on the springs and measured them on the spring compressor to get as much as possible without getting coil bind at max lift. mine carried to 6700-6800 and flatlined past 7000 before droping off. i pulled 442 with the lsx manifold and hoping to get high 450's with the new changes. stock rockers work best and im on stock lifters also.
Ryan,
check your springs, I spoke with a few people that had valve float fom worn out springs on that cam. Check open and seat preasure, spining a nasty lobe like that takes a lot of controle. I spoke with a "competor" shop a year ago or so about the Trex and they recomended a rev kit along with it.
But then again they were also trying to sell me heads saying that I would have 460+rwhp and driveability!
check your springs, I spoke with a few people that had valve float fom worn out springs on that cam. Check open and seat preasure, spining a nasty lobe like that takes a lot of controle. I spoke with a "competor" shop a year ago or so about the Trex and they recomended a rev kit along with it.
But then again they were also trying to sell me heads saying that I would have 460+rwhp and driveability!
Originally Posted by HALLZ
Ryan,
check your springs, I spoke with a few people that had valve float fom worn out springs on that cam. Check open and seat preasure, spining a nasty lobe like that takes a lot of controle. I spoke with a "competor" shop a year ago or so about the Trex and they recomended a rev kit along with it.
But then again they were also trying to sell me heads saying that I would have 460+rwhp and driveability!
check your springs, I spoke with a few people that had valve float fom worn out springs on that cam. Check open and seat preasure, spining a nasty lobe like that takes a lot of controle. I spoke with a "competor" shop a year ago or so about the Trex and they recomended a rev kit along with it.
But then again they were also trying to sell me heads saying that I would have 460+rwhp and driveability!
Rick
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