how high to spin 918s+stock vt?
09-23-2003, 09:13 PM
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how high to spin 918s+stock vt? wondering how high its safe to spin my setup. i have stock valves/retainers and manly pushrods and comp 918 springs. i think its shifting at 6300 now. i dont want to go too high. the springs are a little over a year old too. about 10K miles on them. should i be concerned about them breaking?
09-24-2003, 06:57 AM
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Re: how high to spin 918s+stock vt? 224 112 563.
heads are milled 0.050, rods are .050 shorter than stock. forgot what it was like 4.35 or something.
heads are milled 0.050, rods are .050 shorter than stock. forgot what it was like 4.35 or something.
09-24-2003, 07:02 AM
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Re: how high to spin 918s+stock vt? We revved 26918s (w/ 772 retainers) to as high as 7200rpm (usually closer to 6900rpm) with 2.08 valves on a Procharged LS1 with a B1 cam (.558/.558//221/221//114). No problem for a full season of many 10 second passes.
09-24-2003, 07:31 PM
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Re: how high to spin 918s+stock vt? This is something that you are going to get varying answers on. For me I do not feel safe spinning a stock LS1 bottom end past 6500. My rev-limiter will be set at 6500 and I plan to shift at 6300. (Stock bottom end/ 918s / T1 cam.
09-24-2003, 07:55 PM
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Re: how high to spin 918s+stock vt?
were they stock valves? i wonder how much a difference aftermarket retainers make.
IMO, a stock LS1 bottom end should be fine for a long time taking regular 6300/6400rpm shifts with the occasional blast up to 6600 tops. So long as you have good oil pressure, and are using a good oil that is.
The Procharged car I mentioned above took 6900-7200rpm abuse with those big 2.08 valves and a B1 cam for a few thousand miles before anything went wrong. I should also mention that this particular setup consisted of 8-10 #s of boost, a 100 wet shot, and S2 heads + cam + LS6 intake + exhaust + tuning. 580rwhp (auto trans) through an UNlocked vig3200 without the 100 shot. It was fine until he up'ed the 100 shot to a 200 shot and melted #7 piston
I'm sure if he had eased up on the N2O use the motor would still be fine today....
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09-24-2003, 08:08 PM
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Re: how high to spin 918s+stock vt? is this the guy that blew up at rsd?
im not worried about bottom end, im worried about smacking the piston
valve float isnt good either 
im not worried about bottom end, im worried about smacking the piston
valve float isnt good either
09-25-2003, 05:37 AM
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Re: how high to spin 918s+stock vt?
is this the guy that blew up at rsd?