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Old 09-15-2011, 07:42 PM
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Originally Posted by Ocean-Angler
Hey thanks for all the help and answers -

Looks like the amount of money I spent on this motor, I shot myself in the foot.
THe origional idea was just to give it a little power, till IU bought my LS2 motor and built that a little. But after everything, Ive overspent on a motor that wasnt properly tuned it looks like

Cam specs -
.050 duration - 204 intake 214 exhaust
sae duration - 278 intake 288 exhaust
valve lift .422 intake .444 exhaust
Lobe separation - 107 int 117 exhaust

.050 timing BTC -5 ABC 29 BBC 44 ATC -10 (??)

engine is a goodwrench crate 350 with stock 8:1 compression ( if that helps for compression calculation)
I didnt get a valve job done, I spent quite a bit of time lapping the valves, also cleaned the valve bowl really well.

I couldnt fit long tube headers, theyd be about 1.5" off the ground if I put them on

car weighs 3600 lbs

I dont know if any of this helps..

With that non vacuum advance diz, do you think its really gonna kill me on gas? and rough idle?
The only real issues I see are the chance that the valve guides might be a bit too loose and the vacuum advance missing.

The vacuum advance not being there is something that can be dealt with as easily as buying an eBay Skip White HEI distributor w/vac. adv. or just locate a good used GM Delco HEI distributor w/vac. adv. and the "4-pin" module. These were used in cars through '80 and some trucks through '86 and aren't hard to find at all. Sell yours to get your money back- or most of it, anyway.

The guides and the lapped in valves may or may not be a problem- you can check the valve seal, but that really doesn't tell you too much. The problem w/lapping valves to try to regain the valve seal is the guides- if not replaced- will allow radial runout of the valve and when you combine that w/lapping, you can end up w/the seat off center, etc. Just not an effective way to do it.

Choices as I see it, is to run them as-is and hope for the best, or bite the bullet and have the guides and seats done professionally.

I do not see the compression being a problem w/the cam you have. I would say to replace the stock valve springs if that's what you have on the heads now. Otherwise, you are fine (except for the vac. adv. and possibly the valve job issues) and the engine should be torquey and fun to drive.
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