small block chevy

[mayoman]

i run hobby stock. i got stock 350 all stock 882 heads.
my cam is .454 lift, 272 dur. we run with turbo350 in second(1.52)
and 4.11"s not locked.
so i dyno d this set up (chassis dyno) and at 5250 rpm
i have 88 hp and 102 ft.lbs
can anyone please tell what happening here?

[jveik]

theres no way in hell that your 350 only makes 88 wheel horsepower at the wheels. my 1.5 liter 88 accord makes that lol. theres probably some kind of calibration problem or something. does the car have no balls at all or does it seem like it has more power than the dyno says? if that is the true power you are making, then you are definately either not firing on a few cylinders or have no compression on a few cylinders. i would use a timing light to check if each cylinder is firing by claming it on each wire one at a time and making sure they all make it flash. if one doesnt, then its corresponding cylinder obviously has no spark. maybe if you have catalytic converter(s), one is majorly plugged up?

[silicon212]

Originally Posted by mayoman

i run hobby stock. i got stock 350 all stock 882 heads.
my cam is .454 lift, 272 dur. we run with turbo350 in second(1.52)
and 4.11"s not locked.
so i dyno d this set up (chassis dyno) and at 5250 rpm
i have 88 hp and 102 ft.lbs
can anyone please tell what happening here?

Well, if it's producing Vega engine numbers such as that, and assuming it's running on all 8 cylinders, I'd look at:

Ignition timing
Valve timing - was that cam degree'd?
A/F mixture

If it's not running on all 8 cylinders, find out why and I'm sure you'll stumble upon the problem.

[mayoman]

ya,its sad huh, but the numbers don't lie. i'm thinking maybe the
tranny's eat up some power. or the large duration and big heds are leading
to compression issues, but i'm just not sure.
the dyno did tell me my a-f ratio good. i will check on all the cylinders firing as well as compression test. and i'll recheck lash.
thanks for helping me, and i'll keep ya posted.

[Blue Bowtie]

882 heads? Are you REQUIRED to run those, or are there other options? Stock iron heads only?

[bobss396]

Your numbers should be higher, maybe 3 times what they are, I think something is basically off on the dyno settings.

Your overall gear ratio is a 6.25, if you're running a 1/3 mile track the 5250 RPMs makes sense. Get out and practice with it and see what it feels like on the track. See if the motor pulls up to that RPM fast. Or does it flatten out before 5000?

Bob

[silicon212]

5250 RPMs is the number at which torque and horsepower are the same.

[Rebel Racing 3]

If it is a chasis dyno i heard those these if not worked by the right person are hard to get dead on

[bobss396]

Originally Posted by Rebel Racing 3

If it is a chasis dyno i heard those these if not worked by the right person are hard to get dead on

I sure wouldn't get my bowels in an uproar over some questionable dyno readings. Go out and RUN that sucker. If you have no race track open, find an industrial area on a Sunday afternoon and take it for a ride. Even a blast down a piece of straight road will tell you if it revs up nicely and has a decent pull to it.

We used to do that with a Chevelle bomber car and it was a lot of fun
.

Bob

[Rebel Racing 3]

If your track will let you (I know ours will on sundays) find out what lap time everyone else in your class is turning then take the car out and run some laps and compare times. And see if your playing in the same ball park as everyone else.