What do you suggest as far as cubic inches and rotating parts and or kits?

The top end is Dart pro heads w/brodix intake...heads are bare(thats about all I know about the heads, they will be ported but have not been yet)

I want 8.50's in a 3,000# car on a 10.50

I'm not opposed to puting gas on it either but would rather do that or close to it on motor.

 

Also should I get another block besides a stock one?

Taller deck ht. raised cam etc. in an aftermarket block correct?

 

This a SBC or a BBC,im confused?

 

Me too.

But in general, displacement rules with a very few exceptions. That said, once you get into raised cam bores, non-standard decks, etc. the cost really escalates due to the scarcity of choices in parts. What makes the Gen I SB and the Mk. IV BBC such viable performance platforms is their ubiquity. The various design flaws are well known and people have learned work arounds. Most every part has multiple suppliers and this keeps the cost down and the performance up. It's such a competitve market that products constantly are improved to meet the demand. A marketplace is a wonderful thing! Compare the cost effectiveness of building a BBC or a BBF for a drag motor, then throw in the Hemi (the real one). The BBC is the obvious choice, not due to design superiority but the reasons above.

So, you need to ask yourself the two related questions of "how fast do I want to go.....how much do I want to spend?"

Rich

 

"Ubiquity" is a great word, Rich. How many had to look it up?

I agree with your ideas. Here is a way to determine what engine to build:

1) Determine your goals for the car: 8.50's on 10.5 tires in a 3000# car. Done! That's the easy part.

2) Determine how much power that is going to require, and the torque curve required to get the car down the track. This will probably involve determining trans, axle ratio auto/stick, etc. This is a little more of a challenge, but there are some good software programs theat will help a lot. This one from Larry Meaux (maxracesoftware) might help. There are others.

http://www.maxracesoftware.com/etavbwin.htm

3) Now, with hp and torque needs, determine how to get there. BMEP or torque per cubic inch both at torque peak and hp peak is fairly constant over a large range of engines, believe it or not. If we just look at BMEP at hp peak rpm, 185 psi is easy, 225 psi is tough to get.

Example: 600 hp @ 6500 383 SBC has a BMEP=191 psi.That's 484.8 lb-ft 383 = 1.266 lb-ft/cube. (divide BMEP by 150.8 to get lb-ft/cubic inch).This would be fairly easy to get from a good 383.

Now take that 1.266 lb-ft/cube (BMEP = 190 psi) and plug it into a 468 cube BBC @ 6500 and you are at 733 hp, still not difficult. However if you wanted that 733 from the 383, figure on spinning it to say 7200. Now you need to make 1.396 lb-ft per cube @ 7200 which is 210 psi BMEP, and a much more expensive challenge.

This just reinforces why displacement is the easiest way to get power.

OK, so use 190-195 psi BMEP (1.26 to 1.29 lb-ft /cube) to determine your engine design.

Here's how that works:

If you want to use the ubiquitous BBC, make your max power @ 6500 and use 1.26 lb-ft/cube, which is reasonably cost effective, here's how big you need to go:

800 hp = 513 CI so a 502 would be a good place to start.

850 hp = 545 CI

900 hp = 578 CI (use a 572). Note this is about 180 hp more than GM's best 572 crate engine.

Now if you neded those hp numbers from a large SBC, let's say a 434 which you coud maybe tweak to 200psi BMEP (1.33 lb-ft/cube) you'd need to get that at:

800 hp @ 7300

850 hp @ 7700

900 hp @ 8200

That's a lot more challenging and a ton more costly.


Almost any "Swingin' Richard" (no offense, Doc ) could build a 900 hp @ 6500 572. Not so many could do the 900 hp (NA) 434 SBC.

Of course, you could always spray!

My $.02

 

Jon has just given everyone an excellent way to think about this. The point about displacement is made very clearly. If the OP wants to go 8.50 in a 3,000lb car, he is going to need ~850hp. A 7,500rpm 434 SB is going to be a lot more expensive and maintainence intensive than 6,500rpm 540 BB. You could put that together out of pretty basic parts. Probably a $12-15,000 proposition if you go for cost effective parts. And it would run for a couple of seasons without any major maintainence with any luck. The 434 small block is not only to be more expensive, it is going to be a lot more work to keep it together. Remember, if peak hp is at 7,500, you are going to be shifting/going through the traps closer to 8,000.

So, don't keep us in suspense any longer. Is it a BB or a SB?

Rich

 

383 and 400HP of hose.
Very simple.Shift at 72/7500 and let 'ur eat.
The s10 video ya saw was 3000lbs 383 and 400 hose for an 8.62 et.

 

Sorry I been busy.....It big block for me all the way. I give up on small motors....they just don't hold up and eat parts.


I was considering a 540 or possibly something a little bigger just to make it easier and alot more durable, b/c I want to bracket race it and it will need to be dependable



I have a 383 now and I will put the hose on it, but in all honesty how long will it last? I will be pulling it down putting valve springs in it etc. etc. etc. I'm just tired of bothering with a small block. I considered a LSx motor but for the money I would spend(or the money I spent on a LT1) I could have a lot better motor.

This is my race car, I may mini tub it but I will not back half it.

 

another thing...if it runs 8.80's-70's will be fine. The car is only certed to 8.50

 

540 is a nice choice. Lots of parts available but you need a block with siamesed cylinders to get the required 4.500" bore. That means either Bowtie/aftermarket or a Gen VI OEM production casting. The Gen VI has a one piece rear main and some other peculiarities that may not make it an ideal choice. If you have the $$$, a Dart block is probalby the best choice if you want to go big. If you have a decent Gen IV block, you can go 60 or 70 over and make a 496 which can easily make the hp needed with good heads. Not as much power potential as the big bore motor though. And by the time you prep the block, it doesn't save as much $$$ as you might think.

Rich

 

I can get my hands on a big M fairly cheap. $1,000 it in good shape

 

The quality of the World Products stuff is severely lacking IMO, I'm not the only one who feels this way. I only use the GMPP blocks, and the Dart stuff occasionally - they are very nice as delivered too.

A 540 with a good set of heads and the right cam with all the supporting components will meet your goal. Not cheap but will be scary fast.

 

well If I go a dart block and dart pro 1 heads you think it will do it?

My head guy says to get the pro1's b/c he can get alot of good air out of them and I know someone thats has all of this stuff I'm talking about for really cheap.

I know it won't be cheap, I really don't care nothing is.....If I can do it all for under 30 I could do it all in well under 2 years.

 

Yes - The Dart Pro 1's are our head of choice and flow big air when ported correctly. All of our pump gas 750 hp 502's are built with Pro 1 310cc heads that we port to our dimensions.

FYI, our price for those motors runs 17k to 20k pan to carb.

 

Yeah, the Pro 1 is a really good low price head that can use standard components. The only things "special" they need are guideplates and the stud girdle. Otherwise the supporting parts are generic. If you build a 540 you probably want the 325cc casting as your starting point. They flow pretty decent out of the box, FWIW.

I think you can build a decent motor for less than $17-20K. I suspect that is with components one step up from what is strictly necessary.

Dart block (with prep) ~$2,500
Rotating assy. ~$2,500 (Callies Compstar rods and crank, piston of choice, good rings and bearings)
Heads ~$2,500 (with basic porting)
Valvetrain ~$2,000 (cam, pusrods, guideplates, springs/retainers, rockers, stud girdle (add $$$ for shaft mounts)
Accessories ~$1,500 (timing set/cover, oiling system, valve covers, gaskets, fasteners)
Manifold/carb ~$1,500

That puts you at ~$12,500. Add another K or so for a distrbutor, starter, other stuff I forgot and you are still at less than $14,000. That's pretty similar parts to what I have in my bracket motor and it makes about 700hp out of a 469. There is about $10K in that motor, it uses a Mk IV block. It won't push a 3,000lb car to 8.50's though it does that with a 2,200lb'er.

Rich