Dynamometer Results & Comparisons - 383 Cam choice?

I'm a bit pissed. I've got a nice 383 c.i. short block, decent 243's (stock valves and full port work) Prc gold springs, Ls6 intake and ported tb.and 1 7/8 Hookers. The car is an A4 with a 3600 Trans. spec. stall and Ms4 cam. This thing only put down 430/395 at the tires. Doesn't that seem low? I've talked to some guys that think the cam is just not wright for the combo. Oh, the stat.comp. is @ 11.7. PLEASE!!! Give me your input. Thanks

that seems right being in a stalled auto car with your intake/head setup. What is your redline? I wouldn't be surprised to see you pick up at least 30-40whp by swapping to an aftermarket head(AFR/TFS) and a fast 92/92 setup. Just my opinion though

Tell us more about the heads (full flow sheet would be beneficial so we can see if you're even able to take advantage of that big lift MS4 intake lobe). That LS6 intake is definitely choking your setup. Give us some more info and we can help find the missing power...And keep in mind, that A4 with the 3600 stall isn't going to dyno like a 6 speed, but I'd agree you're still a bit on the low side, but with at least one significant restriction in that manifold.

I'll to copy the flow sheet and post it. I've wondered about the fast 92 for awhile... but a few guys i know didn't pick up anything with their swap to the fast 90. I know the peak flow #'s are @ 290-297cfm at .6-.650 and the exh. was @ 230-240cfm at the same lift...i think...

I think there is more than enough evidence to show that the fast is worth purchasing.

yeah its a bit on the low side,and that cam would not be a bad choice for a 383..I would look at the heads and intake..I have a A4 with a 4400 stall and a 232/238 cam but with a tsp 5.3 heads and put down 430rwhp 407 rwt in a 346ci.

Thanks, guys for the info. I'm looking for the flow sheet still. I just wanted to say I'm a drag racing type of guy. The Ms4 is a 239/242 on a 111. Would I gain anything from going to a mid 23x's dur. with more split? Or a 24x's with more split and timing like 114? I'd like to pick up more mid-range and sum peak. How about that request? By the way, the old bird went a 11.67 @ 117 yesterday with a 1.67 60'

MS4 has really good valve events for a 383. Stick with that.

Heads and intake can make a huge difference. Hell, just because your heads were ported doesn't mean they are better than stock. You posted flow at peak, but you make power by having monster mid-lift flow at .200-.500. Let us see what the flow is there.

I beleave I have found one of my problems. My memory served me very wrong...
and here's what I found. Remember stock valve 2.00int. and 1.55 exh.

intake exhaust (w/ pipe)
.200 139.7 111.1
.300 207.1 153.9
.400 255.5 181.9
.450 271.7 194.6
.500 277.8 200.9
.550 289.3 207.9
.600 296.1 215.2
.650 273.7 219.9
.700 273.7 221.5

Now, how bout them apples.....sometimes hindsight sucks...

For stock heads, I think they are flowing descent. Im not much of a big heads expert, but @400 lift its pretty respectable. @500 lift, it should be a bit higher. I think the stock 2.00intake is hurting you though. ....oh, and what type of Dyno was it ran on (i.e. mustang, etc..)?? SAE or STD #'s??? MAF?? CAI?? EXHAUST?? Spark Plugs and gap?? That would help out.

ok. It was a Dynojet chassis dyno, and the #'s were SAE. My car has a speed density tune, with a SLP lid and ran NGKtr55's with a .045 gap. and a u.d. pulley. I have Hooker 1 7/8 coated w/ 3" collector, with an o/r y 3" into a flowmaster long merge to a 3" s.s Borla open after "cat". Loud as hell...

Do you see any problems with this combo... I think I had @ 24-26* of total timing with no k/r... and a 13:1 afr thru reline... hope this helps... Thanks again...:)

Its gotta be the heads. Can anyone else think of anything else??


...if its N/A, shouldnt the timing be a little higher? ...just thinking out loud

What does the graph look like? Sometimes strokers won't make huge peak power over stock cube engines, but they'll have a tremendous amount more power throughout lower and mid ranges....

Let me see if I can get that posted. As soon as possible.

I've got my friend tryin to get some Dart 225's w/2.08&1.60's, with alittle port work for me...

I'll to copy the flow sheet and post it. I've wondered about the fast 92 for awhile... but a few guys i know didn't pick up anything with their swap to the fast 90. I know the peak flow #'s are @ 290-297cfm at .6-.650 and the exh. was @ 230-240cfm at the same lift...i think...

that is crazy. That MS4 needs to breathe. with your 383, the MS4, and 243 heads... ill bet you could gain a solid 20rwhp adding a FAST in the mix.

just noticed your times. 11.4 @ 119 isnt bad results for a heavy vert and a budget build. However it is clear that there is a lot of room for improvement.

Thanks. Like I said I'm looking into some heads and checking options in the fast 92 direction as we speak...
Oh, and ....the best e.t. I've gotten in this car was 10.78@128 "ON THE JUG"...:)