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Discussion Starter #1
so I'm getting ready to order some parts for my 68 camaro. 468ci reving 9500rpm and going to have a 300hp shot on it. 14.4 to 1 comp. anybody think these compstars would last? i know they can handle the hp, but I'm worried about the rpm. thanks
 

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I don't think you will ever see much past 6800 to 7200 on peak HP with this motor. So why would you spin it to 9500?
 

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Discussion Starter #3
cuz the cam and heads thats in it??? 7200 peak??? sorry i spin mine a lot tighter then that. so back to the ??? of this thread.
 

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Not my first choice.
 

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Discussion Starter #5
i hear you there. its not mine ether. just throwing it out there to see what other people think and use. i know they are better then eagle and scat, I'm just trying to get away from buying a 1200.00 set of rods. and thats what i will probably have to do... :(
 

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I guess it comes down to how many times do you want to build (er...rebuild) this engine and do you have the scratch to do it more than once ?

Curious, how big are the intake ports ?
 

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If your going to spin your 468 to 9500 rpm more than once, ether spend the money now or you will be spending a lot more later.

There is more reasons to spinning an engine to 9500 rpm than cam and heads. So why did you pick that figure. Is this a class spec car?

Blessings.........Ron.
 

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Discussion Starter #9
If your going to spin your 468 to 9500 rpm more than once, ether spend the money now or you will be spending a lot more later.

There is more reasons to spinning an engine to 9500 rpm than cam and heads. So why did you pick that figure. Is this a class spec car?

Blessings.........Ron.
yeah i know theres more. this is just my shop car. not really setting it up for a class. maybe after i get it going and see what it runs i will look into what class i could run it in. I'm trying to find some more info on these rods but i cant. found out eagle rates theres at 1500hp.... but at only 7500rpm. i like the lunati pro mods and there rated at 1300hp at 9500rpm. looks like I'm going that route.
 

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With steel rods and that much RPM you can't go wrong with oliver billets.
 

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i would just buy a magnum and not look back.the price has come down some on those also.
 

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Discussion Starter #15
Why not aluminum rods?
Ive just never ran them. don't know why. and the lunati's are one of the lightest steel rods for the 6.385 rods. 736grams. olivers are 805g. and hears one more good ????
how high would you take a externally balanced motor (bbc rpm's):smt102
 

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If its just your shop car why spin it that high?For the extra 10hp you may make for going over 8000 its going to be more work then its worth.
 

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What's the application here: n/a or boosted ?

If you are going to have to buy a crank anyway, get one that is internally balanced. Makes things a lot easier and safer too. Do you really want your feet and legs next to that weighted flywheel/flexplate at full song ?
IMO, I wouldn't spin a Compstar crank to 9500. You're going to need a better crank - either a Magnum as already mentioned or a Crower piece. Probably no need for a Bryant or Winberg.

If you choose to run steel rods, you're going to need a premium rod such as an Oliver, Carrillo, Dyers Top Rod.
Piston weight will also need to be considered as well. Solid dome or hollow dome, etc.
This exercise will require a max-effort valvetrain as well.
 

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Discussion Starter #18
i have the crank already. and was free. thats the only reason i would run a externally balanced crank. i was going to spray it with no bigger then a 300 shot. Ive been asking around about the crank and everybody is saying not to go over 8000 with it. so now I'm leaning to that and put a bigger shot, around 2 250's. i just hate to buy a crank with a perfect one sitting on the shelf.piston weight is 581g with hollow domes. was planning on lunati full machined rods after all this. but I'm still up in the air on the crank as i don't want to be worrying about it every time i race.
 

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This doesn't sound like a combo I would turn 9500. What heads and cam do you have that you think will still be making accelerating power at 9500? Must be some 1 inch lift stuff. You have the lifter bores opened up for big lifters? Are the bores on the 468 big enough for what i would assume would be some really big valves without major shrouding? External balance I wouldn't turn over 8k. Not trying to rip on the deal just wondering why you have this arbitrary rpm number
 

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Discussion Starter #20
This doesn't sound like a combo I would turn 9500. What heads and cam do you have that you think will still be making accelerating power at 9500? Must be some 1 inch lift stuff. You have the lifter bores opened up for big lifters? Are the bores on the 468 big enough for what i would assume would be some really big valves without major shrouding? External balance I wouldn't turn over 8k. Not trying to rip on the deal just wondering why you have this arbitrary rpm number
it was a combo Ive been thinking about for awhile, but the crank just showed up and screwed that up. as i said earlier, if i use this crank now, i going to change cams, and just take it to 8k, and hit it with a bigger shot. i found a good deal on a dragon slayer crank that is 3.760 stroke. i can use the same pistons just get 6.535 rods. just a thought. be almost a 440ci. and safe to rev. and its internally balanced. cam i was looking at was 290/300 at .050 with 776/750 lift on a 112 lobe sep.
 
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