In reply to Curtis :
If i was only looking for 550 hp id just keep the goodwrench 350 that i had in it originally.
In reply to Curtis :
If i was only looking for 550 hp id just keep the goodwrench 350 that i had in it originally.
In reply to Curtis :
SB2.2? Didn't they turn 9000rpm for four hours when they were relevant engines?
I thought the biggest issue with them was making the flat tappet cams live, with radical things like hardfaced lobes and funky oil spray tricks. Not an issue when you are allowed to run rollers, which have their own issues but those are at least manageable by people who don't get $50m a year in sponsorship money.
And since displacement isn't limited either, yeah... I have a FOAF who built a 396ci SB2 for an RX-7. Made Cup car power but without the Cup car maintenance headaches, and it ran on pump gas because he traded compression for displacement.
bwh998 said:In reply to Curtis :
8k isnt asking much from the bottom end, i sometimes even see the cast crank 602 crates spinning close to that. I have the 604 which uses a forged 4340 piece.
The forging is great. It just means it will eject itself from the block as a twisted single chunk instead of in 30 pieces. I don't care how awesome the crank is, the SBC doesn't have the meat in the main webbing to hold it in place.
And 8k is asking monumental forces to be exerted on the block. You are basically asking for 1.5 times the RPM the block was designed to see, and force is squared in relation to speed.
I'm just going to leave now before someone dies. I've spoken my peace. Feel free to go for it, but unless you spend half of a hundred grand, don't expect it to last past it's first run to redline. This was my business for half of my life. I can get you to 6500 easy. 7000 isn't something I would even attempt without about $10k. 8000 is ludicrous in an SBC.
Knurled. said:In reply to Curtis :
SB2.2? Didn't they turn 9000rpm for four hours when they were relevant engines?
I thought the biggest issue with them was making the flat tappet cams live, with radical things like hardfaced lobes and funky oil spray tricks. Not an issue when you are allowed to run rollers,
Yes, they did... with raised cams, unobtainium parts, a cost of about $50k to build, and they were lucky to last 500 miles on an oval track.
And rollers just add weight, even solid ones.
In reply to Curtis :
6800 rpm (limited only by valve spring rules) all weekend long without issue. Im not limited by those class rules though.
With the th400 I think you would better off with either a ls engine as previously mentioned or building up a big block. Both would be easier and less money than trying to get your sbc up to that horsepower level. If your concerned about weight with a bbc you could get an aluminum block. Now that won't be cheap but probably not any more expensive than what it will cost to build a 650 hp sbc.
In reply to Knurled. :
Any idea why your friend chose to go with the 2.2 instead of an 18* degree or raised runner engine? Who did he buy the heads and intake from?
In reply to bwh998 :
It was a novelty at the time, the R07 just came out and the SB2 parts were coming down in price.
IIRC the heads alone were $10k... but it has been many years.
bwh998 said:In reply to Curtis :
8k isnt asking much from the bottom end, i sometimes even see the cast crank 602 crates spinning close to that. I have the 604 which uses a forged 4340 piece.
Once, you might see a 602 do that. At the stock car track here, if someone breaks an axle and zings a 602, the chances of it surviving are 50/50 at best.
604 is a lovely engine, but for any kind of life, 6500 is about all she wrote.
In reply to Streetwiseguy :
I dont doubt it, because they are limited to basically a stock cylinder head and valve train. Hendren recommended to me a 6800 rpm rev limit because thats where the valves float on this 604 im using. When i explained that i wouldnt be using the class spec head and valve train he said it "should be fine till at least 7500."
In reply to bwh998 :
Curtis is right! High RPM is expensive sooner or later. Any Chevy regularly reved over 5000-5500 will start to cost you money, as in bang it came apart money.
oh sure you can rev it up there briefly and it won't go bang. But a race? Nope.
Knurled. said:pres589 (djronnebaum) said:Why not just get a decently built 200-4R and make sure the torque converter is exactly what you need for your application?
I don't think anyone can make a good statement on heads until we know a lot more. Camshaft? Compression? Rear end gear?
A 2004R would need more RPM than a TH400 because the gears are spaced further apart. Something like 2.78:1 First vs. 2.45:1 in the 400, and second gear is similar.
You're telling me that a transmission with an overdriven 4th gear is going to require more engine RPM for a given road speed than a trans with a direct drive top gear? Am I reading this right?
This project screams "4.8, a call to Comp Cams, and a pair of moderately sized turbos backed by a 200-4R" to me. Fairly close ratio four speed with OD and good aftermarket parts support and an engine whose recepie has been written hundreds of times. But I'm not building it so grain of salt and all that.
In reply to rslifkin :
A stock bottom end is getting stressed at 5500. Better rods and a 4-bolt main will get you to 6500 maybe if you have a perfect balance, but the pushrod valvetrain will be very hard to control.
In reply to pres589 (djronnebaum) :
A low rpm truck engine with a hundred extra pounds of turbo stuff doesnt excite me at all. Might as well just go buy a camry.
bwh998 said:In reply to pres589 (djronnebaum) :
A low rpm truck engine with a hundred extra pounds of turbo stuff doesnt excite me at all. Might as well just go buy a camry.
Lol
bwh998 said:In reply to pres589 (djronnebaum) :
A low rpm truck engine with a hundred extra pounds of turbo stuff doesnt excite me at all. Might as well just go buy a camry.
A cammed 4.8 isn't particularly low RPM. The 1000+ HP heads / cam / turbo junkyard 4.8 that a magazine did a few years ago made peak power at 7k (they didn't say how high they actually revved it).
"I want to use an SBC"
"I don't want a low rpm truck motor"
I am confuse.
In reply to rslifkin :
Not knocking the 4.8, i love them and will probably be using one in a ranger at a later date. Theyre just not what im looking for in this car.
What class are you building this for and/or what will the rules allow engine-wise? I've got a little 305 in my ASedan car that didn't seem to mind spinning out to 6500 at the last race weekend....not a lot of money in that motor, actually, although I won't twist it any more than that to try to keep it together as long as I can. I'm working on a 302 next year that shouldn't have any issues over 7500 RPM...decent Scat crank, some good rods and pistons, and I'll be spending money on the Jesel shaft mounted rockers. There are the tip-of-the-spear guys wailing these up to 8200 RPM on fairly restrictive rules (10.3:1 compression, max .500 lift cam, etc), but they probably have the five-figure numbers that Curtis was referencing in the motor.
In reply to barefootskater :
Yes exactly, what is confusing about that?
bwh998 said:In reply to barefootskater :
Yes exactly, what is confusing about that?
A small-block Chevy with a factory block is a low rpm truck motor... numerous knowledgeable folks on this thread have told you this. It’s simple. If you want a SBC that will rev that high and survive a race, plan on putting 5-figure money into it.
In reply to Rotaryracer :
No class for this car, its just for fun. Is your 305 of the winged sprint variety? They look like solid motors, i was impressed. Used sprint car engines are very tempting because most of them are sold with the mechanical injection setup. Right now i have a 604 shortblock id like to use, it has the 3.48" stroke compstar with some unknown h beams. The problem is when i go to add up the price of good heads, the shaft mount rockers, offset lifters and such, im getting close to what id pay for a complete used sb2.2 or something comprable.
In reply to Recon1342 :
The 55 vette and bel air were both cars though...
Yup. Both are cars.... with 5000 rpm redlines.
What is so hard about this? It doesn't matter if it's car or truck... the SBC was designed as a street motor. Can you make it a race motor? Sure! With lots of money and a 6500 rpm redline. My concern is not that you are completely misinformed, it's that you won't listen to experience. You're going to destroy your expensive engine, ruin the track and piss off everyone around you, possibly kill someone, ... .and then you say, "it's not for any specific race class, just for fun," which begs the question.... why are you even asking? Do you even own a car? Are you 14? I know I'm being a dick, but come on...
You won't spend money on a better-matched transmission because you like the one you have, but you bought a $9000 Crate Insider motor for fun?
I know the Hendrens. Right on their website for both the 602 and 604, it says max recommended RPM is 5800. If someone there told you that you could do 7500 RPMs with it, Kate would have fired them on the spot.
I just want to see the pictures after you try shifting at 7500. You won't make it past the second turn. Like I said, this was my business for half of my life. 20 years, I ate, slept, and breathed hotrod driveline engineering. All I ask is that you please... PLEASE...
TAKE VIDEO
bwh998 said:In reply to Recon1342 :
The 55 vette and bel air were both cars though...
And neither were known for being high RPM screamers...
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