question regarding MS4 camshaft and top end
#1
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I recently built a H/C car and have noticed that the car pulls pretty well once i get around 4k. Question is somewhere between 5 and 5500 it seems to just flatten out and stop pulling. I thought this thing pulled very hard up top and continued to pull all the way through 6xxxrpm? Is there something I should be looking at to figure out why it falls out a little on the top end? I'll be getting it on a dyno soon so I'm sure I'll be able to see more then but for now I was wondering if anyone else has had this problem? Thanks.
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#10
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I would not be ripping it without a dyno tune, that large of a cam is going to run like **** without a tune, I hope you planned on getting it tuned when buying that cam. If not your car is going to be a turd like all of the other locals around here with their cammed LSx's, untuned.
#11
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im in the same boat as you. seems like you and me have been having some similar problems. i took mine down for a dyno tune, and after 5500, the power falls off. im thinking its valve float because the springs have around 5000 miles on them, but they were roadraced before i got them, so they are hard miles. im in the process of changing springs, while im in there im going to check to make sure the cam and crank are dot to dot. also, i was told to check pushrod length. my engine is quiet as hell, no tick or clatter you would expect from a large cammed engine, so im thinking the pushrods might be too long.
what length pushrods did you go with? i have the same heads milled to 58cc's and using a stock MLS gasket (.051) and went with 7.350. im thinking they need to be shorter.
what length pushrods did you go with? i have the same heads milled to 58cc's and using a stock MLS gasket (.051) and went with 7.350. im thinking they need to be shorter.
#12
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im in the same boat as you. seems like you and me have been having some similar problems. i took mine down for a dyno tune, and after 5500, the power falls off. im thinking its valve float because the springs have around 5000 miles on them, but they were roadraced before i got them, so they are hard miles. im in the process of changing springs, while im in there im going to check to make sure the cam and crank are dot to dot. also, i was told to check pushrod length. my engine is quiet as hell, no tick or clatter you would expect from a large cammed engine, so im thinking the pushrods might be too long.
what length pushrods did you go with? i have the same heads milled to 58cc's and using a stock MLS gasket (.051) and went with 7.350. im thinking they need to be shorter.
what length pushrods did you go with? i have the same heads milled to 58cc's and using a stock MLS gasket (.051) and went with 7.350. im thinking they need to be shorter.
I am selling my setup though. I've decided to pull the motor and set it up for about 12lbs of boost. I've always wanted a FI application as opposed to a N02 setup.
#13
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you can still have valve float with new springs. if you have incorrect valvetrain geometery you can also encounter valve float. i experienced a similar issue to yours. my heads were milled and had new springs but i floated a valve and wiped out my motor.