since i dyno'd mine in a similar combo, id say fuzz is pretty darned close. the howell tbi EFI holds you back. tbi has its limits on hp production 330 hp is about tops for most good tuners with spark control. 350 is a select small group. i am 9:1 with more lift than the comp cam and my numbers were pretty solidOriginally Posted by fuzz401
401 - 30 over
Decked, align bored and balanced
10/10 crank, resized rods, all ARP bolts
Forged 9.1:1 pistons
Lunati 58501
Advertised Duration (Int/Exh): 256/262
Duration @ .050 (Int/Exh): 213/220
Gross Valve Lift (Int/Exh): .484/.507
LSA/ICL: 112/108
Cast 502 heads (Mild Port match) w/ roller tip rockers
Edelbrock dual plane performer intake
ported exhaust manifolds
670 TBI GM injection 85lb/hr injectors HEI distributor
On a chassis dyno rear wheel numbers it put down the 292 hp @ 4900 rpm 389 ft/lbs @ 3500 rpm it had a similar 351 ft/lbs at 2000 rpm and carried numbers at and above 354 ft/lbs all the way to 4000 rpm. red line is 5500 rpm and it spins hard on the street to 4500-5000.
As you can see the above are rearwheel numbers, assuming 10-12% parasitic drivetrain loss it should be in that 315-330 hp 420-440 ft/lbs range.
The shop that put it on the rollers called it out with correction factor as 331 hp @ 4900 rpm 443 ft/lbs @ 3500 rpm it had a similar 393 ft/lbs at 2000 rpm and carried the same 400 ft/lbs all the way to 4000 rpm. idles smooth at 500 rpm red line 5500 rpm spins hard to 4500-5000.
I think thier correction factor estimate is a little high but 292 /389 at the rear wheels was pretty respectable. I expect this motor to be around for quite a few years.
cracking past the 1 hp per cube becomes a game of cubic dollars. i usually end up about about .80 hp per cubic inch on a mild street rig build for an engine capible of 5000-5500 rpm and less and that number seems to always be obtainable, past that the supporting hardware costs rise significantly. I've built some healthy 401's with 400 hp 450+ ft/lbs but after then cubic investment goes up exponentially from the 1 hp per cube threshold. alot of people claim 400 hp+ motors but few ever have put them on a dyno to prove or disprove thier performance. Remember all the chevy guys who love to claim they have a 400 hp+ 350 cubic inch motor in thier pickup truck that supposedly cost em $1500 to build and runs on 85.5 octane with gobs of low end torque. my engine is probably realistically a flywheel output rating of 310-320 hp / 415-425 ft/lbs which from where i stand and with what im driving these days doesnt bother me one bit, its a heck of alot more than 90% of the guys on the trail these days have. it might be more it might be less but those are flywheel guestimate numbers that dont mean much since i never ran it on an engine dyno........ its all about when the rubber meets the road and what finally makes it to the ground it what ultimately defines your engine
Heres an engine with the size up from me cam with actual dyno numbers
http://www.ifsja.org/forums/vb/showthread.php?t=121315
If i had it to do over again i probably would run a single pattern Engle cam ground with a touch more duration maybe a 216 or 218 at .050 but overall i love the mild manners of this motor it never ceases to perform when it needs to
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