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4/28/20, 12:14 AM   #1
Stroke and bore opinions
thumper15
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Ok guys got a question and need some opinions. We have a couple non wing groups here in Missouri and I'm looking to put a car together. It's open rules but most seem to be running either 410's or 360's as much as I'd like a good used 410 I've been weighing the idea of a 360 for when the tracks slick off. My question is for non wing would you think a big bore short stroke or a standard bore long stroke be better? I'm not sure a long stroke engine would be needed for the torque without a wing on, and a short stroke would rev quicker and keep the wheel speed up. However, on a heavier track that short stroke might get killed and put undo stress on the motor trying to power through the turns. Any opinions would be appreciated.
 
4/28/20, 7:38 AM   #2
Re: Stroke and bore opinions
sp6967
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i asked my wife she said "no comment".
 
4/28/20, 8:47 AM   #3
Tony74
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Build a 410, your cam selection will have a much more dramatic effect on power curve, and throttle feel.
 
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4/28/20, 10:50 AM   #4
motorhead748
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The only way (not really) to beat cubic inches is with cubic feet....build what you need to be fast enough early in the night to to start up front. When the track slicks off learn to dial it back
 
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4/28/20, 12:44 PM   #5
Re: Stroke and bore opinions
revjimk
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Since somebody brought it up, slight digression: Whats the difference between a 360 & a 410? Bore, stroke, or both?
I've always wondered....
 
4/28/20, 1:38 PM   #6
motorhead748
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[QUOTE=revjimk;527615]Since somebody brought it up, slight digression: Whats the difference between a 360 & a 410? Bore, stroke, or both?
I've always wondered....[/QUOTE
Chevy made 350’s & 400’s as passenger car engines. The 400 had bores at 4.125 & stroke at 3.75. 350’s were 4.0” bore by 3.48 I think, may have been 3.50..
Of course with the engine being all aftermarket almost any combination is possible. I’d say the most common 410 is 4.125x3.800. And a 360 if it’s centered around a 4”bore the stroke is gonna be limited to something close to 3.5”
But does anybody check the cubic inch anymore?
 
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4/28/20, 2:24 PM   #7
Re: Stroke and bore opinions
HDbill
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Almost all of the engines are "Store bought"; built by the prominent engine suppliers. None are interested in building illegal "engines because of the damage that could do to their reputations. The risk/reward simply isn't there. Most of the power comes from the camshafts and from the head gasket up. The advances there now, are fairly slim because we have all been working on that since 1955. Chasis setups and the connection between the crotch and the brain of the driver play a much bigger part.
 
4/28/20, 4:29 PM   #8
motorhead748
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Quote:
Originally Posted by HDbill View Post
Almost all of the engines are "Store bought"; built by the prominent engine suppliers. None are interested in building illegal "engines because of the damage that could do to their reputations. The risk/reward simply isn't there. Most of the power comes from the camshafts and from the head gasket up. The advances there now, are fairly slim because we have all been working on that since 1955. Chasis setups and the connection between the crotch and the brain of the driver play a much bigger part.
Certainly true that no store bought engines are illegal. But at the local Saturday nite track I’m not so sure. And even if they’re some big engines they’re not being run by the guys running up front.
 
4/28/20, 4:38 PM   #9
Re: Stroke and bore opinions
TQ29m
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With very few exceptions, the variables are taken up by the driver, who may or may not realize it. Ja ever try to concentrate with a fly on your glasses?
__________________
"Being old, isn't half as much fun, as getting there"! Ole Robert I!
 
4/28/20, 8:00 PM   #10
kendirt
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Quote:
Originally Posted by thumper15 View Post
Ok guys got a question and need some opinions. We have a couple non wing groups here in Missouri and I'm looking to put a car together. It's open rules but most seem to be running either 410's or 360's as much as I'd like a good used 410 I've been weighing the idea of a 360 for when the tracks slick off. My question is for non wing would you think a big bore short stroke or a standard bore long stroke be better? I'm not sure a long stroke engine would be needed for the torque without a wing on, and a short stroke would rev quicker and keep the wheel speed up. However, on a heavier track that short stroke might get killed and put undo stress on the motor trying to power through the turns. Any opinions would be appreciated.
Is your specific question whether to build a 4.00" x 3.50" or a 4.125" x 3.25" engine?

Neither, I'd buy a good used engine from a reputable source and go race. You can't piece one together cheaper.

FWIW, I think there's a car down there that does a fair amount of winning with a 360. You're on a hard RR correct?
 
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