How much head for a stroker?

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TimDart

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Thinking (just thinking!) about stroking my 260 to 408 for street use with 3.23 gears. My question is, how much head flow/work do i need to benefit from the extra cylinder pressure from the troker.
Here in the UK it is expensive to ship over W2,W5 or Edelbrock heads. Currently i have fully rebuilt smog heads with 3 angle valve job, all new components and mild bowl porting.
 
You can use the 915/308 style heads. They should be ported to raise the amount of air they can move. But the engine will run with them just fine. It might drop off power wise above 5500 or 6K, but with 3.23s..That should not be an issue. I would build it witha flat top piston, and then later, sould you choose to, you can upgrade heads and run a thincker gasket to lower the compression ratio as needed.
 
Tim, it is also dependent on how much HP you want to push out of the engine. Which is the question. So here it is.

How much power are you looking for/to make?

The extra cylinder pressure can be adjusted with the piston upon the build. The ratio has to be part of the build. Of course your not going to build a 12.5-1 ratio engine and stick it wth a cam shaft from a stock 360. But you could just imagine the pressure that would develop.
Thats where the cam comes in. Based on the thinking of where you want to end up, the cam can be ground very simply to your needs.

Think before you leap, ask how far it is before you jump.
 
thanks guys, I'd appreciate suggestions on the build up. I cant afford nor want to live with an very high performace set up. When i put my 360 together I was a little cautious (first Mopar build) and have 9.0 compression and a XE262 cam to suit and now wished I'd built it to a higher level of performance.
My line of thinking is.. do i rebuild with just higher comp pistons and biger cam, or go the whole 9 yards and build a stroker.
All suggestions welcome!
 
Just step up with the cam a abit. If you add headers, (Can you/did you) you'll free up some power. With exhaust manifolds, your cam size is limited unless it's a damn the torpedo thing.
 
TimDart said:
and now wished I'd built it to a higher level of performance.
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What leve do you want? What else makes up the car's driveline?
 
Looks like i've opened a Pandoras box with this query! Driveline is 727 auto with open rear 8 & 3/4 with 3.23 gears. 340 manifolds and full 2.5" TTI system. Ignition is FBO electronic plus custom curved dizzy, initial is 14 deg, all in at 34deg@3,000rpm.
 
Well, with no limited slip unit (Sure Grip..Posi..whatever you prefer to call it) all you're making is tire smoke. But you really didnt say how fast is too fast. Or how much you want to spend. I know being over seas is more expensive and difficult...(I'm building a center section for a Norwiegen(sp?) in Afaghanistan...lol) So for sake of simplicity. I would re-gear the car and put in a Sure Grip first. Then see what you need. My guess is, a simple cam swap to something like the XE274H would do wonders for it. But if you have power brakes, that plan would change. I sure wouldnt rebuild the engine without getting the "rear in gear" first.
 
Thanks for the info Mopar, the rear certainly smokes good, second gear acceleration tends to have the tyres spinning on a good day! Do you think I have enough compression to support the cam you mention? No power brakes so vacuum isn't an issue and i'm prepared to change the convertor to something better too.
Plan could be:
LSD, cam, convertor that would be probably the most productive way of using the available power considering what has been suggested.
 
I sure wouldnt rebuild the engine without getting the "rear in gear" first.
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:toothy7: Ha ha ha. Dead on!

Do you think I have enough compression to support the cam you mention?
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9.0-1 is fine. Another 1/2 point wouldn't hurt, but it is really an issue of what octane you have at the pump.
Does Comp recomend a min. ratio or cylinder pressure to use with any said cam?

LSD, cam, convertor that would be probably the most productive way of using the available power considering what has been suggested.
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Before stroking it, yes! Between the 3, you can really change the cars performance from a little mean thing to a bear of a ride. A true meanace to the public at large. (Or soon to be in hiding)
 
TimDart said:
second gear acceleration tends to have the tyres spinning on a good day! .
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So you want to spend money to make more power? ;) fix the gearing. If yo ustreet drive it and like them, 3.23s are fine. I would look into 3.55 or 3.73s depedning on what center section you have, and add a Sure Grip. Then see how that current combo is. Theb if you want, a cam swap will do it. And no power brakes means that cam would run fine. Just might have a raggedy idle..lol.
 
Raggedy idle..mmm! Bear on the streets, no maybe not.
None the less, good advice, thanks.
 
Not a bear, but you'll know you have a cam in there..And your carb may need some resetting...
 
He he he, sorry, I didn't think. I shouldn't have said "Bear" Just reallllly woken up.
 
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