your issue is the fuel, not the head on 615/632 inches. Though that's not the conventional head I or most would run on an engine this big.

Brodix 383 Headhunters or 383 MC.

Reach out to HSMITH1039. Howie's conventional headed, 383MC, 632 "made 1165 on the nickerson's dyno but went as fast as 6.82 @ just shy of 198 @ 1830lbs" on Q16 and typically runs 6.9x at Numidia, on the hill, in the heat of the summer.

This message has been edited. Last edited by: 1320racer,

with a single carb on gasoline

The latest 632 with SR20 just come off the dyno at PAR with 1298 hp.......

quote:

Originally posted by WHOMPWHOMP:
The latest 632 with SR20 just come off the dyno at PAR with 1298 hp.......

I saw it with my own eyes!

Mr. whompwhomp.... will you please keep us updated on how that PAR SR20 runs for ET. I'll be anxious to hear. What is it going into for a car?...........Thanks,Howie

quote:

Originally posted by gxp7903:
it sounds like most are saying a 615 is to big. so let me ask this- do you guys think there is a conv head good enough that can support a 615+ motor making 1.8 hp per ci or more on a singe alky carb? if so, which head?

It works like this,

Your induction system sets the airflow capabilities which therefore sets HP potential. CID just impacts the rpm that it will develop that HP therefore larger CID, lower rpm needed for peak HP. So give that you really can't say the head is too big or too small unless you start with the HP you want make first and work the other way.

On the alky carb,, higher HP motors need more fuel, obviously,,,, but with alky and higher HP's, you need volume, both to the carb and then to the motor! In addition you need to consider the quality of the fuel that is being delivered to the motor also, especially with alky! This is much harder to achieve with a carb than injection (both quantity and quality). Your typical 1000 HP BBC will run faster on gas than alky with one carb but faster than gas with alky injection!

The OP said he is going to use alky so that is where this thread needs to go. Nothing wrong with running it, we run it with no problems and it works fine. Rather than listening to people that don't run alky carbs give a carb builder that does run alky on his motors and his customers motor and find out what works, what doesnt. There is a lot in camshaft design that makes a difference in how they perform.

I would give Ken Jones a call and ask him about his carbs. Marco Abruzzi runs 7.20's with a alky conventional headed 598. We run 7.20-30's with a alky 622 and 383 HH, We only turn ours about 7200 and that is at 2060lbs with the big tire.

Answers:
Yes a alky carb will work fine
Yes alky injection would be faster than gas or alky carb
Gas carb will most likely be faster than alky carbureted

Ken Jones (618) 533-5605
Dan Davinci (281) 964-7782

quote:

Originally posted by HSMITH1039:
Mr. whompwhomp.... will you please keep us updated on how that PAR SR20 runs for ET. I'll be anxious to hear. What is it going into for a car?...........Thanks,Howie

I will have to find out who's it was...update later...

quote:

Originally posted by WHOMPWHOMP:

quote:

Originally posted by HSMITH1039:
Mr. whompwhomp.... will you please keep us updated on how that PAR SR20 runs for ET. I'll be anxious to hear. What is it going into for a car?...........Thanks,Howie

I will have to find out who's it was...update later...

We ran 4.40's at 2060lbs with our SR20 on gas and 6.96 at the same weight in the 1/4 with a 622 SR 20 that made 1198 ( I believe that is the number) with a fairly tight convertor (needed to be about 200-250 to tight in case we needed to spray at the finish line. Still pretty good for that weight.

We built a SR20 632 last year,and haven't run it yet.....but I'm way behind 1298.....but the proof is in the pudding.....

dyno HP numbers are meaningless as to what ET you'll run. All that matters is what's printed on the time slip.

I have a dart big m block sr20 headed 598 been 4:48 on gas. Uncle has a all aluminum 604 sr20 that's been 4:36 on gas also. Both are PAR motors. My motor used to be injected on alky and it made more up on gas on the dyno.

Me and da boy have a 638.rons terminator and sniper x heads from schmitt 7.38-7.46

my 582 with head hunters ran a best of 4.54@152 in mineshaft air and averged 60's the rest of the year with a davinci 1250 alky carb. currently building a 615 with a little different camshaft for the alky. guess we will see if ive done enough homework in a few weeks.dont expect a huge increase in et but maybe a few numbers?

quote:

Originally posted by dragracer2757:
my 582 with head hunters ran a best of 4.54@152 in mineshaft air and averged 60's the rest of the year with a davinci 1250 alky carb. currently building a 615 with a little different camshaft for the alky. guess we will see if ive done enough homework in a few weeks.dont expect a huge increase in et but maybe a few numbers?

Those are impressive numbers! At what weight? What kind of rpms you turning? What does it run in the extreme heat?

Let us know how the 615 does!

1930lbs shift at 7300 and cross 1/8 mile at 7350 ish. the extremely bad air greasy track days high 60's-low 70's depending on how i set it up for the day. i broke a couple rods the race out so since i had to buy it all basically,i figured why not make it bigger.i went with the 615 over the 632 for most all of the above reasons.i was lucky enough have some similar conversations with tracy dennis as ed had. to me it all makes since,guess we will see!

quote:

Originally posted by dragracer2757:
1930lbs shift at 7300 and cross 1/8 mile at 7350 ish. the extremely bad air greasy track days high 60's-low 70's depending on how i set it up for the day. i broke a couple rods the race out so since i had to buy it all basically,i figured why not make it bigger.i went with the 615 over the 632 for most all of the above reasons.i was lucky enough have some similar conversations with tracy dennis as ed had. to me it all makes since,guess we will see!

Where are you racing at when running 60's on average? I would also be curious about your cam for the 582 if you'd be interested in sharing.

middle tennessee area,alabama,ky etc. and it was a bullet cam , hh582- 283/302@.050 113 centerline installed at 111 and .857/.834 lift.being on alky i always thought it might like intake open and closing points a little different but hard to argue that it didnt run well as it was

You must only run 1/8 I take it. 4.30 gear? What are you changing the cam to for the 615? Will the 615 be steel block also?

mostly 1/8 mile,1/4 on a rare occasion ,4.30 gear and the new cam is also a bullet.its a little bigger on the intake,moved opening a closing points and basically the same on exhaust,.865/.860 114 installed 111 and its a steel block,big m.like I said,i don't expect much more ,maybe 5-8 hundreths and a mph or two. about 5 weeks and we will find out!