8k rpm ...

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People learn this crap from the ragazines that say everyone has 800 horsepower. There was a guy posting pictures of his Duster leaving the starting line on Facebook the other day and was saying his 800 horsepower 2800 pound car runs 6.30’s in the 1/8
I told him my 575-650 horsepower engine ran 5.98 at 2880 pounds. Lol
 
We just ran into the same question. The guy has the money and for some reason wants to turn 8K in a street car.

I asked him hiw often do you race?

Never, i just want a fast streer car that sounds like this.
Pulls up a you tube video of a race car doing burn outs at about 5K? On the street.

I ask, how often do you think you will be able to hit 8K on public roads?

Well when ever i want right?

Me.... uh no.... at 8K you will be breaking the law in first gear....

For some reason he is stuck on this magical 8k number so i sent him to talk to my engine builder (who is not cheep) and i haven't herd back yet....

That's what separates the dreamers with the wherewithal from the dreamers without the wherewithal. The ones with it will achieve it. The naysayers never achieve much. J.Rob
 
I find the best way to get my 8000 rpm kicks is to take my wife’s new 5.0 mustang when she is not looking...
 
People learn this crap from the ragazines that say everyone has 800 horsepower. There was a guy posting pictures of his Duster leaving the starting line on Facebook the other day and was saying his 800 horsepower 2800 pound car runs 6.30’s in the 1/8
I told him my 575-650 horsepower engine ran 5.98 at 2880 pounds. Lol

Your the best. Golly gee. J.Rob
 
This is why my new engine is gonna run boost.

I can make way more HP than the block can handle, turn 5,500-6K and if im lucky it will last a while.

8K is a killer of engines and cash, both will die in a hurry.

If you wanna spin that fast find a builder who dose off shore racing, spread those cheeks and lay your check book on the counter.....
 
Your the best. Golly gee. J.Rob


You too buddy. I love reading about expensive engines being build for DYNO hits with modified blocks and every other grey area trick only to hit a bragging number for the Ragazines. Lol. You dyno guys are a touchy bunch.
 
This is why my new engine is gonna run boost.

I can make way more HP than the block can handle, turn 5,500-6K and if im lucky it will last a while.

8K is a killer of engines and cash, both will die in a hurry.


In fact, with today's parts, 8000 isn't really a big deal.

Using junk designed in the 1960's where that RPM was considered an impossibility then 8k is a *****.

BTDT.
 
Of course it can be done. We can lift heavy objects into space.

Is it cheep, no.

With good people and enough money almost nothing is out of reach. Just how bad do you want it and do you want to try and make a falcon 9 fit for trips to the ice cream shop?
 
What folls do with their money is none of my business. Making happy customers is.
 
I get the OP desire, use to love to drive my Honda Prelude and shift it to it’s 7800 redline and with its something like 4.90 gears. Is that a reason to build an high rpm engine ?

Problem with building a 340 plus like that is gonna need a lot of airflow and make too much power to be able to get into it a lot.

Most times I’d say go with a bigger engine but in this case I’d think it would be easier to accomplish his goals with a 273,
ported out the factory heads or notch the block and run magnum or even 1.88 340/360 heads with pistons that have a quench pad since your gonna need custom pistons anyways, that leaves cam either solid or solid roller, done right should be able to make it reasonably streetable maybe with a peak hp at 7000 rpm or so and a 7500-8000 redline. Wouldn’t be the most powerful car in the world probably 400 hp tops. Add some deep gears and probably be a fun package.

Making power with mainly head flow and trying to get the cam reasonably small for the build level would be the trick in making it more streetable.
 
Are you wanting to do this with a flat plane crank or a cross plane?
 
Are you wanting to do this with a flat plane crank or a cross plane?
Cross ... honestly never figured it would be this big of a deal ! I shift at 6k now with my stock 340, it gets there pretty quick. Didn't think another 2k would be that much trouble ....
 
Cross ... honestly never figured it would be this big of a deal ! I shift at 6k now with my stock 340, it gets there pretty quick. Didn't think another 2k would be that much trouble ....


More money than trouble. Great heads, best roller lifters you can buy, lightest rotating assembly you can afford, and go for it.
 
My head is just fine thanks for worrying about me though. I pretty much already assumed stock parts would not do it without carnage at some point. I know there's a lot that goes into it, was just trying to get some specifics from those that have done it successfully
Don't let the self proclaimed DR . Give you info ..If you reduce your rotating Mass by knife edging and lighting your crank have pistons made with a small block Chevy wrist pins thin ring pack with gas port holes and smaller skirts use high side of your clearances to get your parasitic resistance down to a bout 10lbs to rotate your lower end..Get some Program Billet steel 4 bolt main caps and a good Machinist to do your work.. Of course you need to run a sump style oil pump,Good heads, cam and valve train..Not going to give you all My secrets..lol But I shift mine at 7,600 to 7,700 and Pulls up to that #
 
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Diminishing returns/exponential increase in stresses. Easy to spin it to 5000 add 1000 rpm takes X, add another 1000 rpm takes much more than just X.
 
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