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Discussion Starter #21
I can't find the thread, with this new for crap format, but I think it's Peterson that makes a combo external wet sump/Vac pump combo. It's a pretty trick set-up. If you have the space you might want to consider it.

There's a thread in here about it somewhere.
G, I used to have one for a small block. Very nice piece indeed. Peterson is the schit!
 

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Discussion Starter #22
That's the nice thing about 615 engine.You dont have to run it high rpm and still have good shift recovery torque to work with.9 deg head could be designed to run way upstairs but it will be expensive to build and maintain.Do you a good sr20 headed 7500 rpm peak eng.Shift it 78-7900 and be amazed how well it runs.And you prob find if you short shift it at 7200 it still run ok.
I just used 9° as an example but I hear you. The SR20 is what i had in mind and if the rpm range is as you say, that would be in my wheel house as long as its not a maintenance monster. I know, im asking for the world. lol
 

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Discussion Starter #23
All depends on your goals. I think there's a lot of misinformation out there that's carried on through the years about rpm and reliability and where a Big Block should rpm peak.

If you want X amount of hp, it requires X amount of RPM. you can't get there without RPM. For 1200 hp, you don't need 8000 plus RPM. If you want 1300, 1400, and up.... you need rpm especially with smaller engine like a 615. I have an SR20 611 that runs occasionally 9200+. Peaks power near 8500. That's what is required for the hp level desired..... RPM isn't the goal just to have it as a goal, it's the requirement.

Also there's a lot of 9 degree this and that thrown around... has there been anything fast with a 9 degree head? Do not think you will just use a 9 degree head and turn 9k rpm. That will be a valvetrain eating machine. That will require special lifter layout, and a king kong rocker system.
Chris,
Thank you for chiming in. RPM is not my goal, just more hp than the average 1100-1200 hp engine that sees 7200/7400 would be nice if it can be done without getting exotic and be done with conventional heads and wet sump.
Can the right aluminum rod go 100 passes before cashing them in shifting at 7800?
What kind of hp does that 611 make? Sounds like a beast.
 

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Chris,
Thank you for chiming in. RPM is not my goal, just more hp than the average 1100-1200 hp engine that sees 7200/7400 would be nice if it can be done without getting exotic and be done with conventional heads and wet sump.
Can the right aluminum rod go 100 passes before cashing them in shifting at 7800?
What kind of hp does that 611 make? Sounds like a beast.

100 passes on that kind of rpm is no big deal. I would expect many more runs than that. I've had 120 runs on that 611, but recently we did have a rod issue and I'll be backing that way down.
 

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Bracket SR20 engines make between 1175 and 1250hp and cost betwween $25 and $35K depending on block, cubic inches, cam and head/manifold porting with steel rods and will easily go 200 passes before needing a basic freshening. Chris's 611 is not that engine, rather a max effort big $ piece that probably doesn't see 125 passes before a compete tear down.

 

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I don't believe Chris considers this a MAX effort deal for Dave or Butch. A GOOD or SERIOUS effort YES, but not max. Chris recently posted that if Butch's was a MAX EFFORT would mean trying 20 cams and other various induction parts to get the best possible result.
 

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2.2hp /cu.in, 9,400rpm and a 1.200" lift cam is max effort regardless if the combo is not yet optimized
Your screen name is fitting...
"Just a fuck off"
But it should be.....


"Just a fuck up"
JAFU to the front....
Go hide under the sofa in your mommies basement and shit yourself.
 

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Rpm is a function of the engines head CSA and your mach index. Reqairdless of your engine size, piston speed, etc. Turning your engine to a high rpm successfully making power is limited by your port area.
 

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Rpm is a function of the engines head CSA and your mach index. Reqairdless of your engine size, piston speed, etc. Turning your engine to a high rpm successfully making power is limited by your port area.
Pretty much.... at least part of the equation. However, you can have the same cylinder head on 2 different short blocks the same CID and they can be 1000 rpm apart at peak.... and 100-200 hp.
 

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Absolutely. My point was saying your going to take a engine to a set rpm without consideration if the head can even get you close isnt very useful. Still a lot of factors in equation too
 

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Discussion Starter #33
Im not very good at making myself clear. lol
....but so many folk making assumptions and my lack of knowledge doesn't help. I typically don't dig too deep on things I cannot afford so my knowledge on 600+ that turn the same rpm my 565 does is next to nothing.
I say that to say this, I didn't imply I was going to "force" the motor to 8000, rather get the right head to "happily" go 8000. Now thanks to some thoughtful insight from you guys and a little more digging, I see you dont need 8000+ rpm to get north of 1200hp. ....which is really cool.
Looks like I won't be getting the 615 anyway. I think my buddy got it sold. He does have another one though. We may trade my motor and trans and some $$ for his motor and trans. It has Curtis Boggs Pro Edelbrocks on it and I won't want to mess with it. It made close to 1150 and is super fresh. We will see.

Thank you for making me a little smarter Guys.
 

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Typically "big" heads with larger CSA needs more rpm to keep the intake charge motion up. Many factors go into this like runner length, taper, radius on port, and on and on. Some people like Chris who are more knowledgeable than I am could expand on this but like he said you can have two motors the same but have different outcomes based off these variables
 

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.

So how much does a tunnel ram effect RPM needed??
Or is the cam, compression, velocity, ?? the only thing that matters??
Id it a wives tale, or fact??
Even considering a modern conventional head like the sniper, instead of a Big Chief,
isn't sticking that big monster on top changing the sweet spot??

.
 

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The ramming effect comes largely from the 3rd order tuning of the intake tract. Ideally you want the Sonic wave coming back down the intake track as valve is opening. This captures the energy helping move the charge. A piston speed of 6000fps seems to be where most ultra performance engines are
 
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