Help Please! I have a 440 stroker(496) It has 10:1 with 193lbs cranking pressure.18inches vacuum @ 800rpm. Comp-Cams 294solid 248@050 Lift 0.560 with 1:6 Rockers.Installed straight-up.Was using Weiand Xcelerator 7512 Single-Plane Manifold.650 D/P Holley. Were using Hughes Engines Heads,Stage 2 452's Factory Iron. Now running Stealth/440 Source which have same pressure & revability. 6800 in 1st & 2nd on 4-Speed New-Process with 2:75 Gears out back. Car wit me weighs 3960lbs & runs 12:00-12:25@117-118mph in the 1/4 mile.
I have a Six-Pac set-up with Fuel Technologies Metering Plates.
Something is wrong, it does not like to pull much passed 6000rpm. 64 jets centre,10:5 Power-Valve;
84 jets for end carbs. Accelerationion seems considerably less than 650 as well.
Any ideas, especially from someone with similar set-up or thoses in the know.

A 650cfm carb spins that 496ci engine 6800 rpm.. Pretty amazing considering an engine is basically a air pump & at 6800 rpm it wants to move 975 cfm of air that thing ought to really wake up with a Sixpack...

Yeah! i realise this. Had it on a chasis dyno & the 650 was only down 13 HP on an 850 D/P.
Actually, its the 850 i use to produce those 1/4 mile times, but that 650 is a real side-winder as well. Pulls best to about 6100-6200, but just holding, it still goes pretty hard out to 6800.

I was curious about the horsepower your motor is putting out. My 493 inch sixpack motor has it's horsepower peak down at around 5500 rpm and runs out of cam at just past 6000 rpm, but it sure does run good at and below those numbers.

Hi! Just got outa bed. Umm! Horse-power was 418 RWHP with 850 @ just over 5800. Can't remember the exact revs, but the torque from down low just climbed straight up compared to the 650. I usually shift at about 6-6100, but it still pulls pretty good out to 6800.

That sounds pretty healthy. How much does that work out to at the flywheel?

Hey, another Big Mike

Nahh! I'm Bigger; you see, i have a - between my names.

Gidday! Probably about 530 at flywheel, but who cares; its what hits the road that shifts [Edited by Moparts - Keep it clean].
A bigger cam would definately make it a lot quicker, but then my fuel consumption would go through the roof.

Beat this! I just put my weight & terminal speed into the Horse-Power calculator in the tech archives, & it says i make 508 HP at the wheels.

Running out of fuel? Do you have an electric fuel pump?

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Those are some good numbers. With a 17% driveline loss, that comes out to 594 horsepower at the flywheel!

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With those kind of numbers you should be dipping into the 11s.

Thanks for the chat guys. I only occassionally wind it into the 6800 area if I wanna screw up Boy-Racers (Brains) in their Jappa's by takin the odd one for a ride.
At the drags, i am some-what into 3rd gear,maybe half-way. It would be well in the 11's, but this is a car i can just loaf around in,&,once moving at 10mph will blow the socks off most comers.
Quite happy with tall gears, afterall, low gearing only has the punch in that first instant.
In low, with full tank of juice & 60ft of 5/8th chain in the boot,& the 850 on, she'll srew sideways every time even if i accelerate smoothly & then at say 50-60mph push that lasy third of throttle. Tires are 255x45x17 ZR-Sumitomo's.

Oh Yes! Forgot to answer the fuel-pump question.
Yes, its a Mallory 140 with 3/8th pipe.
I also have 1-7/8th headers, all mandrel bends.
As for the sound,at the drags everyone raves about how damn crisp & strong it sounds.
Lots of people come & tell me its the best sounding car there. I sit on 7000-7200 doing my burn-out for them.

If your running 12.0's with a 2.76 rear, you have nothing to complain about!
Why rev the engine over 6K if it does not do anything for performance?
With a single 4 setup, a Holley HP 950 has made huge differences over 750 and 850's with the strokers I have been involved with!
IMO, you picked a pretty good all round cam for a street car, I have never seen one with that much vac at idle, wish mine did.
From all accounts, the Stealth heads run pretty close out of the box to the Eddy heads, and they dont flow enough for your combo to make max hp and probably why it does not make any more power
over 6k. If you shifted around 5800 you would probably run better times at the track.
Here is my combo for an all around street car.
493 stroker, 10.54-1 comp. Comp custom solid from Dwayne Porter, Porter racing heads. Specs off top of my head, 254/258@50, .582/.597 on 108*.
Out of the box Eddy's with Isky 8005a springs. Hooker S/C 2" headers with 3" full(quiet) exhaust.
Torqueflite trans with Dynamic tight 10" 3600 stall converter. Factory 6 pack, cold intake, staggered jetting on ends with QFT jet plates 78/84, center carb 65 mains, I believe I drilled the accel pump nozzles to .035 and used the red accel pump cam in the #2 position, stock 30 cc. pump. My vac in gear at idle was around 7" and I ran a 3.5 power valve. I am also at sea level. 69 RR with a/c and a 6 point bar, 4120 lbs w/driver.Dana 60 w/3.54 gears Best run through mufflers on 30" tall slicks, 11.48@117, average times through the muffs on Goodyear Eagle GT 2 street tires, 11.78@115, 60 ft. in the 1.80 range, but on a well prepped track, 1.74 was common. Best et's were found to be with a shift point of 5800 rpm. My cam was a little big, but when Dwayne spec'd it out, I was planning on having the heads ported which I have since done. Unfortunately, I had a garage fire that burned up both of my Mopars and the whole shop before I had a chance to run the new heads. I won't know until next spring how everything will do when I put the new car togeather, but I think it is safe to say you could benefit greatly from some proffesional porting on your heads. Also be sure you have a good fuel pump so you don't run out of fuel on the big end. With your mph, no doubt you have all the potential for low to mid 11's in street trim, a bit more gear would sure help. Hope this helps!

Hey! Thanks for the info. I have played around short-shifting gears etc: & where i am is the fastest & most consistant i can do. I do tend to win most races, but i'm only there to have a bit of fun & 'cos people love wathing my car.
Anyway, this jetting; which sides do the 78's go in?
I won't bother porting these heads as i have some Indy SR's sitting there as well, but just can't be bothered at the moment building another set of headers. I'll get round to it before Xmas though.
Any other suggestions would be much appreciated.
I'm 52 & been running worked 440's since '87 & have good understanding mechanically & do all my own work;susspension;brakes;diff;gear-boxes etc:
I use to be an incredibly hard road-driver, but they would jail me if they caught me today; now i just have memories of what use to be.
Yee! Harrr!

I'm so Sorry as well for the bereavement of two Mopars. Bet that was like a death in the family.
Trouble is; its not just the money, but all the work you put in, & then its also two more beloved "MOpars" (tears).
Mike.