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Same kit as EGAY #2424353676 but will include .040 over flat top pistons for 10.5:1 which he said would be fine on pump gas, is this correct? I was told by fellow VMFers to stick to 10:1 for pump gas, but if I can get away with 10.5 I would like to do so. The price would be the same, $999. Does that sound fair to you? Seems good to me.
Thanks for your opinion.
 

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IF you're gonna use aluminum heads, you can get away with 10.5 to 1 very easily on the street (I do it every day in my late model F-body LT1 and LS1 10.5 to 1 engines). If you are still using cast iron, you may or may not have problems, depending on the cam profile, timing and so on. For your info, cast steel crank 347 kits can be found for about 100 or so bucks cheaper. Also, make sure you check where the piston pin intersects the oil ring area to keep from having oiling problems.....

randy
 

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FWIW...I have built quite a few engines......A 10.5:1 compression is fine and so is a 10:1 compression.

If you have electronic injection, then that is something completely different......The following only applies to a carb......

That is if you only want to spend $3.50 for race gas. 10:1 compression barely works with iron heads and premium pump fuel. You'll have to kill all of your timing and then you'll lose a lot of power. When you retard your timing, that will cause your engine to overheat, and your headers to glow at part throttle. Part throttle is expressway driving....

Well, you can run more compression with a dragrace cam because of a lot of overlap. But, if you want a lot of low end power, then you'll want to run a little less overlap and a lot less duration with wider centers. What that does for you is gives you more cylinder pressure at low RPM, which in turn gives you more low end torque and power....

I do get a lot of power from 9 to 9.5: compression engines. One more thought.....What happens when the oil companies lower their octane ratings again?

Gary.........::
 

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very, very good points Gary.....

here in California, the highest octane rating available these days is 91. Given the fact that most late model high performance MINIMUM requirements are 92 octane, we have ALREADY lost power (late model powerplants through the computer retard the timing to compensate for the decreased octane). Of course the day may eventually come when we have NO fossil fuel available - not that it will be gone, it will just be LEGISLATED out of existence....

sigh...

randy
 

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Uh Thats MY Kit ::

Uh I got robbed ::

Thats a GREAT PRICE! I Paid $1395.00 ::

Hmmmm where were they when I was looking ::

BTW, I'm running "Worked" origianl 55cc heads with 1.9/1.6 valves & Comp Cams 281h Roller Cam and have occasional ping probs I'm still trying to work out.

Ken
 

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The kit looks very similar to what I used.
My compression is 10.8:1 and I have never heard the motor detonate yet on 91 octane fuel with my aluminum AFR cylinder heads. I paid $950 IIRC for my 347 kit.
 

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re:What happens when the oil companies lower their octane ratings again?
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Well Gary....like all other changes to our gasoline....they will charge us extra for the change....

kind of like the price hikes for adding MTBE into our fuel.....which would have been a waste from distillation process anyway....and then they want more to keep them from adding it to our fuel....

Bunch of greedy ^$#O$#
 
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