any builders out thier care to take a guess?

3175 Views 17 Replies 10 Participants Last post by 1FST2M6, Jul 9, 2002

novass

Discussion Starter · Mar 28, 2002

I have a 400ci block bored .30 over, Edelbroke Performer RPM heads, Victor Jr. Intake,B&G 850 Cfm carb, Comp Cams 292, everthing is machined and balanced. compresion is 10.7:1. Hei distibutor.

I have yet to turn it over (damn Canadian weather)
Can anyone even give me a guess at what kind of power I may get? Were my torqe range/shift points might be?

1 - 18 of 18 Posts

reddwarf

· #2 · Mar 28, 2002

Well, you asked for a guess, so...500 HP maybe

Good for 6500 RPM, shift at 6000...

Anybody agree?

1BAD80

· #3 · Mar 28, 2002

I go with reddwarf , I had a motor close to yours.
The 400 likes to be short shifted.The cam comes on at 2500 rpm, what type is your converter?
You mite consider a good distributer HEI dont have the upper RPM output. Mine ran cold here in Mich. and liked to gas foul plugs after a set of Bosch Plus 4s, never had a problem. Their expensive but garrentied for life.
This site has a dyno to play with.
http://http://ubb.cincyspeed.com/cgi
bin/ultimatebb.cgi]

Jooooooe

· #4 · Mar 29, 2002

Considering that the LS-6 454 has 450 HP and it's spec's are 12.5 to 1 CR, and a bit hotter camshaft, I'd have to say 500 HP is a bit high. I would more in the area of 375-400, maybe. It would do good to match the output of the 375 horse 396.

gbovaird

· #5 · Mar 29, 2002

Ever tried the "Desktop Dyno 2000" program,reasonably priced and very addictive.It is a windows based program and any enthusiast should give it a try, this would also be a great way to test different cams and combintions. You can even use this virtual build up and try it at the drags with the sister program "Drag 2000". Check out <a href="http://www.motionsoftware.com" target="_blank">www.motionsoftware.com</a> for more info.
P.S. Make sure you give yourself lots of time to play! cause once you get started you'll have a hell of a time trying to stop!

novass

Discussion Starter · #6 · Mar 29, 2002

Thanks for the input forlks...I do have a HEI distributer,(but will be looking to change it after a good break in of the mill) and I am running a 3000 stall on a TH350 tranny that has a shift kit (none of this B&M crap)

I am aware that these are fast to rev up and like to be short shifted.

I called a few shops today, found one that had JUST built the same (very close) to mine. 510HP at the fly on pump gas.

I am looking forward to dropping this mill into my 2600Lb Nova. Should be a little fun.

[ March 29, 2002: Message edited by: novass ]</p>

novass

Discussion Starter · #7 · Mar 29, 2002

dead link

Originally posted by 1BAD80:
<strong>I go with reddwarf , I had a motor close to yours.
The 400 likes to be short shifted.The cam comes on at 2500 rpm, what type is your converter?
You mite consider a good distributer HEI dont have the upper RPM output. Mine ran cold here in Mich. and liked to gas foul plugs after a set of Bosch Plus 4s, never had a problem. Their expensive but garrentied for life.
This site has a dyno to play with.
http://http://ubb.cincyspeed.com/cgi
bin/ultimatebb.cgi]</strong><hr></blockquote>

reddwarf

· #8 · Mar 29, 2002

He is running RPM heads and a single plane manifold. Maybe 500 is a little high, but I'll bet you a donut it's well over 400HP...

Then again, just a guess....

Jooooooe

· #9 · Mar 30, 2002

I'll meet that donut and raise ya' a cheese cake.

reddwarf

· #10 · Mar 30, 2002

Cheese cake....that's a little rich for my blood

RHamm1320

· #11 · Mar 30, 2002

I love to run my computer simulation on these engines. When I first run the engine, I just barely got over 350 hp. I ran this with the comp cam 292H camshaft (Hydraulic), HEI distributor and 175cc on the intake port for the Performer RPM heads. These three items keep the upper rpm power low.

I also ran a second combination, using a solid camshaft, MSD distributor and took the intake ports to 200cc. The improved the power quite a bit.

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reddwarf

· #12 · Mar 30, 2002

Hmmm. According to Edelbrock's catalogue, the Performer RPM package (smaller cam and dual plane manifold) made 420 HP adn 415 ft-lbs on a 350ci...wonder why the same heads with a bigger manifold and cam would make 50 HP less with 50 more cubic inches....could the RPM heads be choking the engine that much?

Or does your Desktop program give rear wheel numbers? I'm baffled

<img src="confused.gif" border="0">

cdsumlin

· #13 · Mar 31, 2002

I ran your setup on desktop dyno using #60999 heads. I used thr flow data from their website and a generic single plave intake. Used large tube headers and mufflers.

peak hp at 5500 was 441 , with 427 at 5000 and 438 at 6000. Peak TQ was 456 at 4500.

Entered into the dragstrip program from there (in a 77 camaro / 3.55 gear / 2500 stall shows a run of 12.07.

I don't know how accurate that is, but hope it gives a little more info. I think the drag program is optomostic for my car, but the program does help figure out how individual changes effect the package. Good Luck.

RHamm1320

· #14 · Apr 1, 2002

I do not know how Edelbrock gets 420 HP and 415 TQ out of a 355 with a hydrualic cam. I have ran numerous drag race only 383's across the dyno with sportsman heads, Victor Jr intake, 600 lift solid cams and Holley 750's. These were always between 460 to 480 HP (only 45 HP more).

I have never seen the exact stats of how they test their engines, but I am guessing its steady state testing (as compared to normally a 200 rpm/sec acceleration test). This could account for a 5 to 10% difference.

They could also be 'stretching' their numbers a little (testing in cooler ambient temperatures with the barometric pressure well above normal). I know of some big engine builders selling xxx hp crate engines that somehow lose 100hp on the truck ride to our dyno facility. I remeber one test I accidentaly left the inlet air temperature sensor on the manifold and the dyno's automatic correction program made it gain 100 hp in back to back pulls.

The final thing, the computer simulation is never going to exactly match a true dyno test. Also do not read this post as me not liking edelbrock. I think their products are great and will always continue to use them.

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reddwarf

· #15 · Apr 1, 2002

One thing I am learning is that desktop dyno programs vary a LOT in their results.

The engine you ran for me made about 30HP less on someone else's dyno. I guess it depends on how specific the inputs are and of course it's still only as accurate as the programmer...

I agree, the real thing can only be estimated, but it sure is cool how far these boxes have come. When I first started, about all you could do was word processing and spreadsheets

wrenchturner

· #16 · Apr 1, 2002

Another pot shot 425 to 450 just a geuss

garye1935

· #17 · Apr 2, 2002

If it's all clicking, I'd say 450.

1FST2M6

· #18 · Jul 9, 2002

www.dynojet.com find out for real.. usually $50-65 USD to run...

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