Had Bryan at PCMforless dynotune my LPE 383 with small Joe Overton cam today....

382rwhp/352rwtq
a/f was 13.0:1 and flat the whole pull
timing was 36 degrees
weather was 95 degrees!!!

It previously made 400rwhp and 430rwtq in the cool weather when the driveshaft broke on a rich tune. the 430rwtq must've been a spike or something and we didn't save the graph.

Both were Dynojet dynos the only real difference was the very hot weather. I'm hoping that cooler weather will yield higher numbers since we all run faster in the cooler air...

Thanks to Bryan for all his tuning help today...He's definitely a good guy to go to...I just wish it had made better numbers...

--Alan

 

There was a rumor around here that Joe Os cams seem to dyno a little low...I had gone 11.76 @ 118 before I changed the cam and had the heads reported and freshened by E.B. Porting...I guess we'll see what the track says...

My mods are as follows:

LPE 383 4 bolt block
Callies crank, Oliver 5.85 billet rods, JE pistons
Aluminum LT1 heads CNC/hand ported by LPE and Eric Bradby 2.00/1.56 valves
compression ratio 11:1
LT1 Intake port matched to heads and to 58mmTB
30 lb injectors adj. regualtor
stock fuel pump
Joe Overton 22X/23X .56X"/.56X" on a 111
LPE CAI
LPE shorties with air tubes/pump/egr intact
gutted CAT
Borla cat back run with no plates


Bryan said that everything looked great and he spent some time tweaking it in..First pull was 366/334 so he helped a lot...I hope it was the weather...

--Alan

 

head flow numbers? And for your setup isn't cam's duration low?? I think 23x/24x off course its related to your flow numbers..

 

Something seems wrong, i would think you should break 400 or atleast hit it alot easier with that setup. I mean the cam isn't huge, but you dont really need a big monster cam to hit those numbers...Something has to be wrong....espeically if you dyno'd higher before. Maybe bottle neck somewhere? air intake or exhaust wise? Hell i know someone that hit those numbers with a H/C package on a stock bottom end lt1 with bolt ons. His heads flowed like LE3 and he has a Comp Cams 230/236 112lsa cam. I think something is wrong somewhere...perhaps fuel? I'd def check these things out, let us know...

 

I can't find my head flow #s from E.B. Porting, but I could see more port work done to the intake side when we got them back from him. I know the cam seems small, but I was going from an LPE 211/219 .533/.560 and Joe knew that I didn't want to go too big and was supposed to have matched it to my head flow #s. I have always liked small cams for the street and hell, it went 11.70s @ 118 with the old small cam from LPE...

I don't think its fuel as Bryan also said that the A/F was steady and perfect at 13:1...I'm not running out of fuel and its not bad fuel as there was no knock detected at 36 degrees

The only change I made between the earlier dyno pulls was the replacement of the Granatelli MAF back to the descreened stocker for tuning.

The car still feels like an animal..I'm not going to panic until I hit the track when the weather cools off. and maybe do a dyno pull back at my first dyno place to see whats what. I gotta believe that cool weather will produce better numbers like it does at the track...

--Alan

 

I think that something is wrong, cause the torque is so low...those look like h/c 350 numbers not 383 numbers. hmm...............

 

In my experience, Joe O cams aren't always dyno queens, but they kick butt at the track. So I wouldn't worry about it just yet.
Did you try less timing? Was 36 actual degrees or degrees set in the program?

 

Ion, I think Bryan tried 37-38 degrees and got slight knock and went backwards to 36 after disabling the knock sensor to see if it was false knock. Sorry for my ignorance, but I'm an old school carb guy with not a whole lot of computer tuning knowledge...36 degrees proved optimal according to Bryan. He said that in his experience Joe's cams like more timing, so once we lost the knock we left it at 36. a/f was steady at 13:1 with no "running out of fuel."

Jason at FBC talked to Joe last night and said that he thought the numbers were ok for a 95 degree dyno session. I'm guessing that since I usually run 3-5 tenths slower in this kind of heat that it would affect dyno numbers...Cooler, denser air usually means more hp...

I'm not going to panic yet. My 12 bolt just arrived and we'll put it in next week. After that we'll wait for some cooler weather and hit the track to see what happens...Then back to the original dyno site to compare apples to apples. The car still runs like an animal...I should've taken up stamp collecting...

--Alan

 

not sure why temperature would make a difference if the numbers are corrected, they made no difference for me ever, dyno numbers in sig with Joe O' cam.

36* seems a bit high, I run mine at 32* at WOT top end, I can run 36* but I tried 34* and lost power, the more efficient the cam the less timing it needs up top.

 

I run 32 degrees also...Did you dyno at same shop as before when you made those higher #'s? Important thing here is to compare apples to apples...Every dyno will have its differences..As long as your happy is all that matters

Cody

 

Hey try adding more fuel to the car if you haven't and see what happens.. To compare #s My car made 385rwhp and 370rwtq with the auto heads cam stock bottom end and Ion tuning the car... My cam is also bigger.. Like Ion said though take the car to the track .... Dynos don't win races..

Chris..

 

That's the reason I asked if it's real timing or tune timing. 32 in the program at higher RPMs will be 36 real degrees and that's the sweet spot I also found for most Joe O cams.

 

This dyno session was at a different facility (both Dynojets), so I know I'm not comparing apples to apples. We experimented with different degrees of timing and 36 seemed like the sweet spot also. I don't know about adding fuel as 13:1 a/f made the best power/torque. The first pull was 366/334 so we found 20 more peak hp and tq and even more under the curve. The only change we made from the first dyno session was the removal of the Granatelli MAF as Bryan doesn't like to tune with them on. I'm tempted to put it back on and see what happens. I emailed the Granatelli folks to get their advice. I was told that the Granatelli just leans the a/f out and picks up hp. Their website suggets otherwise...I do know that I was stuck in 12.0 territory until we put on the Granatelli then came 11.80s with no other changes...that was back in 1997...

In any event, I'm happy with the performance. It drove like an animal on the ride home from the dyno...As far as tuning goes Bryan seemed genuinely enthusiastic about tuning my car and did not have one bad word to say about any other tuners. I have to believe that he knows enough to know what works the best and got everything he could out of my combination. The real good news is that my Strange 12 bolt is sitting at Fbody Central and will go in on Monday..Once this weather breaks we'll see what the track has to say...because you guys are right...dynos don't win races..

--Alan

 

 

Thanks LT4POWR...that was very helpful...Ion said the same thing and I think he's tuned 1 or 2 cars on the dyno.... If Joe is not concerned than neither am I and I guess he would know a little also...

--Alan