348 Dyno Results

Just put my 348 on the dyno. First and last run the tech just getting to 7000 rpm's. Third run was aborted. The 2nd run did not get to 7500 rpm's, but still pretty decent #'s? 267 hp and 211 torque at the rear wheel. Looks like the curve was still going up. That's with bypass and challenge exhaust.

Question would be ND is the car running lean? Based on A/F ratio looks like around 14 to start and dips below 13 above 6000 rpm's. MAF resistance is 381 ohms. Can I or should I run richer/less resistance.
View attachment silver005.pdf

 

That looks pretty close to spot on, to me. You could run a *little* bit richer, but not much.

 

Some observations:

Having several different runs with such different numbers means something was wacked. I'd suggest trying again to get 3 similar overlapping runs. Goth is really good at getting these machines to work right.

Other than that, your peak Hp could be higher than 7000 rpm so you should have a test up to the fuel cut off - 7750 on your car, IIRC.

The A/F looks lean to me, at least compared to my car. But, fuel type, additives and atmospheric conditions can skew this, not to mention if the dyno has a bias. Eg., the dyno we use reads a bit lean according to the owner. I think my engine is in the 12's at cut off.

I'd like to see another few runs, dude.

 

Vince, they were using the same program as your test in 3/08. If you look the graphics are not as good, but the numbers are the sae corrected numbers. The difference is the tech cut out the test too early. That's the difference in the numbers. This is my nephews muscle car shop and they were running newer GTO's and Charger's Sat. They peaked and then dropped dramatically above 6000 rpm's. I don't think the tech knew how high the Ferrari would rev. This was also a drum dyno, not the hub dyno. Would that make any difference?

The curves are otherwise the same. The A/F ratio curves look very similar to yours. Right around 14 and dipping to below 13 above 6000 rpm's. There charts are not as good.

ND, I am going to get one of the ECU's out to test. Looks like the challenge chip has higher peak hp above 7500 rpm's. I am pretty sure the timing is advanced at least to Euro specs.

Does a higher A/F ratio mean lean or rich? What would be optimum?


http://ferrarichat.com/forum/showthread.php?t=188948&highlight=348+dyno

 

It's a start, this initial run. Hub dynos are supposed to be skewed compared to drum dynos. A/F's measure ratio of air to fuel. Stoich is 14.7 so lower is richer; higher is leaner. Our engines tend to run rich at higher rpm. This is to allow for cooling. Perfect Stoich is 14.7, but we don't want that in our engines at high rpm's. I think they use the richness to reduce detonation and keep the pistons from melting. Fuel additives skew Stoich depending on the % and type of additive. We use 8% MBTE and it's worth a few Stoich points, so you have to make the adjustment in reading your A/F. EG., 13 is in the 12's. ... I think.

I am really very curious about the Challenge ECU chip maps. ND just read my Serie Speciale chips and found them to be the same as the Spider maps. Makes sense, actually, since the Spiders are derivations of the SS cars in several ways (exhaust, gearing and rear wheel offset).

 

Saaaay..........how about the good doctor shipping ND his challenge chips so that we can get redline comparisons? What do ya say Richard?

 

No joke. I'm trying to get Bruce to send his, the slacker!

 

It's coming. I just need time to take one out. Alot going on know. May be after vacation end of June.


I did read the old thread on the MAF setting. Mine are set at 381 on both. Looks like uncorrected A/F ratio is right on with 13.5 to 14 lower and drops to around 12.5 above 6000 rpm's. The graph's do not show the increments well.

I will have to talk to my nephew about the software. I will try another dyno run and have the tech take it to the rev limiter and see were the power drops off. Angelis (I think that's his monaker) on this sight had a Euro 348 dyno up to 8150 rpm's. So there may be more up top.

 

FYI, I got my MAFs at 373.

 

Good to see another dyno reference... !!! The numbers vary quite a bit on these runs.... ...... on Vinces they varied by about 1 hp after the first run.................... so now a few questions:

1. what exhaust system was run?

2. what kind of dyno, hub or wheel ?

3. what 'smoothing' level is this?

4. are these numbers SAE corrected?

Sorry for the big batch of questions, but some of the text was cropped on the PDF...

BTW thanks for posting.... !!!!!

 

The variability is the tech was stopping the run before peak hp. Look at the graph's closley and see. 1st run right about 7000 rpm's, 2nd run (highest at 267hp and looks like it was just peaking) was just below 7500, 3rd run was aborted, 4th run (249hp) did not even get to 7000. Torque curves are similar. The curves are all consitent. It was more tech errror. I think he was afraid to go higher.

To answer your questions:

1. Running challenge exhaust with bypas resonators

2. Dynojet research single drum dyno. wheels sit on the drum

3. I don't know

4. yes sae corrected. SAE: 1.02