http://www.shafiroff.com/472_675_engine.asp

 

Is that a SBC? or BBC?

I think 580HP that is 500rwhp is achievable NA with a HR. I think!

THe combination has been done... Ask mindgame for his heads, they are 15* heads and supposedly flow very very well.. I think they were around 6k. Put a 383 long rods in and I think you can reach the 500rwhp mark w/o that much... IIRC he made 567rwhp and 10s N/A with a solir roller... detune 67rwhp with a streetable cam and it shouldn't be that difficult.

Heck... AI has a few 425rwhp 350CID with stock castings!! That is 500 to the crank... so the goal is not unreallistic and I think 580-600 can be achieved. Even more if you have the $.

Ls6s are some in the 500rwhp range with a h/c package on pump gas with a still streetable cam.

Now.. 580-600rwhp.. that is tough. Probably better going off with an LS6 7L and still you get around 560rwhp n/a.

 

ways to increase power: more cubes, more compression, better fuel, more airflow, less parasitic drag, etc.

 

How much $$ you got?

Sorry, I'm just not much for beating around the bush.

You can go expensive.... or you can go real expensive. Either will get the job done.
If you're going to do it NA and with a 4" (variant) bore motor, it's gonna have to be real expensive if you want any degree of "streetability" (as Rich said.... a relative term). If you don't spend more money ($$ for some real cylinder heads) then its gonna need alot of cam, alot of revs and alot of maintenance. Especially if it's going to be a daily driver.

Then there's the cheaper route..... Build a really large small block and carb it or the more expensive route.... a really large small block with fuel injection.

The real big motors are gonna be more streetable. They'll make the power you're after at lower revs and they don't necessarily need exotic 12, 15, or 18º heads to do it.

So, how much you looking to spend?

-Mindgame

 

I see what you mean man...

So basically a 383 isn't enough motor to do what I want....

My idea of a street car is something I CAN drive to work, but probably won't. I don't care to spend most of the weekend adjusting/tuning to get it to run either.... That's why a solid roller didn't look too appealing to me. But, you have to pay to play....right?

So, I guess I'll spend the 13k for the 472ci SBC. I'll have over 600 hp out of the box with a street friendly pump gas motor.... I'm curious as to what that motor will produce with a bigger head....

 

You can make 415-435 rw/hp with a well ported set of 200cc heads.

I like the AFR heads, But the Darts are also good.

Check out Pro Action, they are availible through summit for cheap, I have built several motors with them now, and they are a very good head, they come with the seats blended and good short-side radius. A set of angle plug 220cc raised runner aluminum heads with the right cam will get you there.

There is no need for 18 deg. stuff.

 

That being said, can I get ~500whp with a little more?

My goal is 500whp on pump gas. I plan to run a TH350 (thanks for the advice Rich) with a 12 bolt.

 

I assumed you were refering to a 500 crank hp motor, 500 whp is pricy and takes some thought, but yes, another 20 to 30 cc in runner volume will supply enough air, but you will need to have a cam that will work with that combo... for that kind of power number and with how extreme the cam is going to have to be, you really should be running more compression...compression is not just for more power, the cam needs that extra compression to work efficiently, 11:1 and race gas would be ideal.

just my .02

 

My thoughts exactly. But, can't I run an MSD adjustable timing control so pump gas could still be used? I could retard the timing while on 93 octane then bump the timing back up when I add some race gas to the mix... right?

 

Fickle,

You can easily build that kind of power on the street with pump gas. We do it all the time. It takes a large engine and great heads and that's it.........oh and the green stuff!

 

Great! I'll give you a call so we can chat....

Yummmmmy, an LS1 in a 1st gen....

 

383,5.7 rod, flat tops, 11.0 to 1 or 11.5 to 1 static compression, 9.0 or so dynamic compression, heads that flow 330/360 CFM@.700( more the better, more head=less cam=more streetability) 240 cc runner 23* head done correctly will do the job, used 18* stuff is my choice, floating around everywhere.. Solid roller cam, Stealth Ram intake, 1300 CFM Monoblade, 42 LB injectors(or 50's if needed).....or a modified Victor intake with a 980 CFM Demon Carb. 1 3/4 to 1 7/8 stepped header, or a set of straight 1 7/8 headers.

I know a guy that has run a similar combo on engine analyzer pro software that makes over 700 HP on pump gas....but ya know its just a simulation. Remains to be seen....the LS1 guys are doing it with 346 cubes, small(er) cams...but they have 15* heads. Shifting under 7000 rpm.


500 wheel horsepower will be much easier to achieve with a manual trans....BUT car will ET much better with an auto....CMotorsports can build you a 700R4 that will live behind this combo, bout $2500 a pop. Be cool streeter with OD, and have that (I think) 3.06 1st gear.

BIIIG DAAAAAVE

 

A lot less $ in a 382 ls1 with ls6 ported and polished heads by cartek and you arelooking for 500rwhp even through an auto.

 

Agreed!

Just to give Fickle an idea.... a friend and I put together a 427 ci small block. Motown block, 254/260 .624/.601 110lsa Cam Motion cam, GM 18 deg. heads (280 cc), 10.8:1, Speed Pro rings, yakity yak..... all said and done, she put down a peak of 691 hp (7000 rpm), ~600 ft/lbs on a Stuska dyno.

Nothing really engineered out on this engine... just good parts, a bit of experience and great heads.

Not to mention, the CM cam which probably sounds big to alot of you, is VERY streetable in the big small block.

-Mindgame

 

Yep you can't make big streetable power at low rpm with a small engine unless you ave ablower and then you have heat to deal with too. You can make big power at higher rpm but at some point you can only turn it higher on any engine. It's all in what the guys wants or can put up with and how fast he wants to go. I can't even fathom all the posts by guys on here and elsewhere that call me and are dumbfounded why there 355 doesn't run like what they want and it only turns 6500 rpm. It won't ever run like a 427 turning 6500 rpm period.