I have sold the engine out of my chevelle , the reason why is It did not reach my ET goal of High 9s on engine . So Time for a new engine . I have not nailed down what ci engine I want to build or what Kind for that matter . My Question is Is it possible to build a pump gas engine that can make 900 hp naturally aspirated ? I have a link to one such but just don't know . In my dreams I would like to run a mid 9 on engine on pump gas . can it be done .
Jim's runnin' high nines but he's gear jammin', too. Shouldn't be too hard with today's cylinder head and camshaft technology.
THINK CUBES - at least 540
Jim came pretty darn close with "Bruiser", a 555ci with pretty much all off the shelf stuff. I would think that with something a little bigger like a 583ci short deck motor, the same planning and thought going into the build, 900hp should be achievable. Then, there is always the option of going tall deck, in which case 1000hp is more than possible with less planning and less effort. Its really not as hard as it sounds when you have enough ci and a good solid top end breathing for you....just my $.02
Jim's 555" build would have been close to 900hp with the addition of a lite ring package/piston and vacuum pump and a little more aggressive on the cam. Running the bore out to 4.600" would help also.
Problem with the Shafiroff is they dont seam to run the #s, and may be over rated
HP wise.
Someone on this board recently biult (or is building) a mid 500 cube deal with a set of Curtis Boggs heads, it sounded like a killer deal that should make around 900 on pump gas I believe. Who was it?
we built a 572 bbc 2 years ago with the intent of centrifugally supercharging it a year later, so the compression was 9:1. motor made 730 on pump gas and ran 10.10 in a 3300# 68 camaro street car. owner changed his mind about the blower, so we raised the compression to 12.5 and added nitrous. motor made 880 natural and 1206 on the bottle. still drives the car to cruise night and runs 9.10 natural, 8.5 nitrous (now race gas). i would build this motor bigger(632), lower the compression for 93 octane; this combo would make 900 and easily push your car into the nines. i'm guessing your chevelle weighs 3700-3800# and obviosly hooks hard. this conventional headed bbc would be the easiest pump gas naturally aspirated combo to run the number and fit the car with the least trauma.
I don't know if it would hit 900 but it will be strong. There were some glitches after the break in run on the dyno so we don't have the final numbers yet. We are waiting for the vendors to get parts back. Mike is so meticulous it wont run unless it's right....
To me Pat at Nyes under rates his motors by a long shot. Had a friend just dyno his '57 Chevy pickup with one of Pat's 383's in it make 398hp at the tires through a TH400 and a 9". Pat only rates that motor at 450hp at the crank. Pat builds a nice motor, thats for sure judging by what I saw in my friends truck. He also offers bunches of options and will work with you to build something in the same general price range as one of his "crate" motors. Even though Ive seen Pat's work in person and seen what kind of power it makes, I still would probably talk to Mike before I settled on one of Pats motors.
I put the shafiroff link up because its hard for me to beleave there getting this power out of this engine . I have narrowed it down three builders and shafiroff isnt one of them . and here are the engines Ci Im thinking about .
As I'm sure you remember, I built a 582 last winter. I went with that as it was about as big as you can go in a 9.8 deck block (actually can go 588 at 4.625 x 4.375).
I avoided the 598 as they really need to be done in a 10.2 block which adds even more weight which was a concern.
565 and 582's are good combinations...just gotta get the right setup to make good power using pump gas. I'd say it's gonna take a ptetty good effort to make 900 hp...850 shouldn't be too difficult, but 900...
My suggestion is to talk to Tracy at Sunset as he's built a ton of the conventional headed 565 & 582's and would know what one can make on pump gas and how much effort it would take.
Yep I followed it and liked it . Im not sure what way im gonna go right now pumpgas or high compression . and I talked to sunset last week nice guys for sure .
I think that the way your car works a 540 or 555 done right will get you where you want to go. My 555 is seriously compromised by my car weighing 4000 lbs. Stand by and it should go back on the dyno again soon. Head porting and cam selection are for moving the land yacht.
yea Ive been watching your build to I think its gonna rock . I would be glad to field test it for you when it is done Im sure my bumper would not like it however .
I'm thinking that you are going way too far in the other direction. I think 900 is going to be too hard to hook, and it will start breaking a LOT of stuff. Mine is under 900 hp at 3200 lbs and goes 9 teens at 146. I think if you can make 800 you should be good for where you want to be.
Ray , you are prob right . but I cant help but to think that I can do it . you should see what these guys are doing down here with a 8 " slick way bigger engines than im building and some with stock suspension . kind of a spin off of 10.5 racing .
Has anyone seen the '69 on dragtimes or utube running 9.40s? Pump gas 555 with dart 325cc heads. Stock weight street car NA. Its solid black with red pin stripe. Check it out. I would love to know what kinda numbers he's putting down. Maybe he would tell you how he did it.
Bob I will never know if the set up I had would go in the 9's but I think it would have with a few changes. I would like to be able to do it in the heat . The guy I sold the 498 to is from up your way in MO . K, city . It will be going in a 68 chevelle .
As John said....The 555" we did could have been real close with a light ring package and a pump. It really was a bolt together deal without a lot of tricks. Moving to the 355cc Darts, maybe a 4.600 bore and some cam could for sure do it and also move RPM range up a little higher to make it easier to hook.
I helped a buddy do a 632" a few years ago. He pretty much picked all the parts originally and I fixed it and put it back together after his original builder missed a few big items that allowed it to blow up while on the dyno. It wasn't exactly how I would have done it...but it worked OK and made around 880 HP on pump gas. It had 11.0 compression, Brodix CNC 3Xtra's, Super Victor, 1150 carb and a .700 lift *mild* solid roller designed to make cross country cruises. Think Power Tour and Drag Week stuff.
I think that with some opened up heads, a Sniper or well ported Super Victor and some more carb and cam....it could have done great. It also used heavy ring package and no vacuum pump.
I would prefer a smaller package and some RPM to really run strong though.
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