Supercharged or stroked 340

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IRISH RT

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Got a 340 block getting prepped for a new build I had a 412 in in mind but. Then I considered standard stroke scat crank 6.123. Scat rods 30 cc dish pistons which would give about 8.3 compression ratio. Heads edelbrock Victors with a 671 supercharger. Our estimates are 500hp without 671 and 650 hp approx supercharged
Your input would be appreciated thanks
 
IRISH RT said:
Got a 340 block getting prepped for a new build I had a 412 in in mind but. Then I considered standard stroke scat crank 6.123. Scat rods 30 cc dish pistons which would give about 8.3 compression ratio. Heads edelbrock Victors with a 671 supercharger. Our estimates are 500hp without 671 and 650 hp approx supercharged
Your input would be appreciated thanks
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How about stroke it with Scat 4.00 inch forged crank then supercharge it! 65'
 
Supercharged builds you hp and torque cubic inch only gives you torque.
 
Both as I am but based off a 408. Note: Really good pistons are pricey. Depending on how you plan to run it, a stock 340 block may not do to well pushing beyond that hp range. If you are going to flog it a lot, you might want to consider a R block/resto 340 block.
 
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IRISH RT said:
Got a 340 block getting prepped for a new build I had a 412 in in mind but. Then I considered standard stroke scat crank 6.123. Scat rods 30 cc dish pistons which would give about 8.3 compression ratio. Heads edelbrock Victors with a 671 supercharger. Our estimates are 500hp without 671 and 650 hp approx supercharged
Your input would be appreciated thanks
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After great Discussions with My Engine Builder and after doing all the Calculations , Supercharging with a 671 makes sense, Next Question is which block 340 or 360 because he can achieve the same in either block, might be a waste using a rare 340 ?? and the 360 has bigger main journals
 
My answer on the 340-360 question would be to run what you have but be careful with the initial tune-up. Go conservative and ease into it.

Jack
 
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GTXperience said:
Both as I am but based off a 408. Note: Really good pistons are pricey. Depending on how you plan to run it, a stock 340 block may not do to well pushing beyond that hp range. If you are going to flog it a lot, you might want to consider a R block/resto 340 block.
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Icon has a 2618 forged piston which is specifically designed for boost. At $500 for a set of pistons, a blown stroker is a feasible cost effective option. $500 is actually cheap as you're getting the best of both worlds, blown/stroker.
For those of you considering a blown stroker, the icon piston is a great choice, off the shelf too!!!
8.8CR with 65cc heads= perfect for boost
 
MiradaMegaCab said:
View attachment 1715093101

Icon has a 2618 forged piston which is specifically designed for boost. At $500 for a set of pistons, a blown stroker is a feasible cost effective option. $500 is actually cheap as you're getting the best of both worlds, blown/stroker.
For those of you considering a blown stroker, the icon piston is a great choice, off the shelf too!!!
8.8CR with 65cc heads= perfect for boost
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We need 8.3 to 8.5 CR 4 inch piston 30cc dish to go with edelbrock Victors 58cc
 
IRISH RT said:
We need 8.3 to 8.5 CR 4 inch piston 30cc dish to go with edelbrock Victors 58cc
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With a .039X4.18 gasket(FelPro 1008) a -35cc dish piston will net you 8.35CR
You sir are gonna need cu$tom pistons.

How much work have you invested in the 58cc heads?
Perhaps sell them and get 65cc heads to use the icon piston, in a 408 stroker..
Or use the 58cc heads with a flat top piston and run E85...
What blower, intake manifold are you planing on using?
Best of luck on your build!!
 
Heads are of the Shelf new Edelbrock Victors CNC ported ,Block Sleeved down to 4 inch bore. Blower we are looking at is a Hampton 671 , Scat forged 4340 360 standard stroke crank , 6.123 H beam scat rods , and yes possibly custom pistons 8.3- 8.5 CR 30cc Dish approx , Steel Main Caps Girdle , Arp bolts all the way Through, deburring the block , oil mods etc
 
GTXperience said:
Both as I am but based off a 408. Note: Really good pistons are pricey. Depending on how you plan to run it, a stock 340 block may not do to well pushing beyond that hp range. If you are going to flog it a lot, you might want to consider a R block/resto 340 block.
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Its an early 340 1971 , Been sonic tested Engine builder says its good to go, It a gamble by the time I pay for sleeving etc R3 might be worth the investment , But are the a copy of the LA 340 Will everything bolt up ?????????????
 
My Engine guys say they work best with the rest of the combo reason being raisede ports and flow 225 and 58cc , chambers , them heads add about 6K NZD as I have to get custom headers made , I have a pair of RPMs and headers already ,
 
Ahh, you're in NZ.
What kind of octane is available for gasoline?
Typically you would run large CC chambers with boost, to drop the CR.
The Victor heads are great but keep in mind, the blower will push the air thru any port obstruction in the RPM heads..
The Victors are serious heads but I'd still consider not using them for your boosted application.
The custom pistons and headers that are required going that route is gonna add serious money......
What's the intended use? Full out track or street strip?
StrokerSul has a nice cast blower manifold.
 
MiradaMegaCab said:
Ahh, you're in NZ.
What kind of octane is available for gasoline?
Typically you would run large CC chambers with boost, to drop the CR.
The Victor heads are great but keep in mind, the blower will push the air thru any port obstruction in the RPM heads..
The Victors are serious heads but I'd still consider not using them for your boosted application.
The custom pistons and headers that are required going that route is gonna add serious money......
What's the intended use? Full out track or street strip?
StrokerSul has a nice cast blower manifold.
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We got 96-98 octane , would run aviation fuel on the strip , Intended use is 95% street 5% strip about 10 days racing a year which would equate to 50 passes a year, got a quote from Cleggs for the rotating assembly which include custom pistons bearings etc $2800 USD approx , Have you got a reason other than expense for not using the Victor Heads, What is or who is StrokerSul????? Thanks
 
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