8k rpm ...

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Only way to know for sure is to have it checked. Put another tach side by side. I’ve seen them out a thousand rpm on the top end. Kim
 
I have a bit of time spent with a stock bottom end 340 at ~8k. Your needs depend on how much time you expect to spend up there and if you want it to get there in high gear as well as low gear.

The big end of stock rods will go egg shaped after about 125 runs. You can take them out and fix them once and then you throw them out. Stock rods are about all gone so...decent rods and light pistons. A good (roller) cam and valve springs, good heads and intake, probably a Dominator, and a well detailed oil system.
 
AJ/FormS said:
I'm with YR; give your head a shake.
Why the heck are you even thinking about this, for a streeter?
8000rpm in 2.45 first gear with 4.30s and 88s(28"tall tires) makes 60mph, so about 99% of the time, you will be in first gear, or downshifting into first gear. You will probably need a 5000stall Tc to not get caught by the stinking 59% 1-2 split, and to not to fall into the no torque hole below 30mph, where even a stout 318 will be right on your bumper.
There is no rear gear made, nor any Torque-Flite made, for this to be a street-combo, that won't lock you into an ugly rpm zone. Anything bigger than 4.30 will force you to shift before hitting 60, and then your car will lose rate of acceleration, and your zero to 60ET will suffer.. Anything less will lock her onto the rising part of the power curve, and your zero to 60 ET will also suffer. And of course 65=3355rpm at zero slip with that 4.30/88 combo, so that pretty much precludes driving it very far, which is good, cuz the lousy,lousy fuel mileage will become a thorn in your wallet,lol. And finally, reving to 8000 in second gear will get you to 102mph with the 4.30/88 combo so you just wasted one entire gear. The engine will not again hit the powerpeak until almost 140mph. You won't get there normally aspirated.

Here, IMO, is a better idea, put a 230/235*Solid-lifter cam in it, so you can actually drive it on the street, gear it to hit 60/65 at the top of second gear, and set the rest up so it will survive the occasionally buzz to mid 7000s, cuz it won't matter if she's fast or not, because the tires will still be spinning anyway. So then you can both drive it, and get your hi-rpm fix, and if you do it right, blow the 360s away.
IMO as a streeter, you want the power to be at whatever roadspeed you need it to be at. So if you need power at 35mph in first gear, then you co-ordinate the rpm and the gearing to maximize them to your roadspeed need, and build the engine to make power there. If you need the power at 45mph, then you set it up for that. And if it ain't enough power, you either get a bigger engine, or supercharge the one you got, or whatever..
But with an 8000shift rpm, I'm guessing you will get a powerpeak at 7600, so a torque-peak at say between 5500 and 6000 , which with 430/88 is ~43mph. A well planned 360 could (depending on your Convertor) eclipse your power there with a 235*cam and have more power at all lesser roadspeeds. While your 8000rpm engine is just getting up on the cam, the small-cam 360 is already on the powerpeak and getting ready to shift. So ok sure, you'll beat him to 102mph; but the big question is; can you beat him to 60? and if yes, how many times can you do it with only 12 gallons of the most expensive gas you can imagine, on board? Remember, it's a streeter and you kindof need to build it so it can still burn street gas, so that if you run out, you ain't walking.. and leaving your ride sitting somewhere it ain't supposed to be.

I'm with YR; give your head a shake.
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party pooper :poke:
 
only guy i know hitting 8 bells is using an X block some crazy expensive crank and rods brodix heads with some crazy cam and springs . Good luck with the build and make sure to post a sound clip of those 8 grand blasts . it can be done but will cost if you expect something that will last . think the valve train is the weak point
 
AJ/FormS said:
I mightabin a lil harsh,lol.Sometimes I get cranky,lol,

You wanna talk about the Canaanites?
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Nat said:
only guy i know hitting 8 bells is using an X block some crazy expensive crank and rods brodix heads with some crazy cam and springs . Good luck with the build and make sure to post a sound clip of those 8 grand blasts . it can be done but will cost if you expect something that will last . think the valve train is the weak point
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Lol sorry for bringing up an older Post. I was searching for anyone who bought an old r5p7 engine
 
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