Mustang and Ford Performance Forums banner
1 - 15 of 15 Posts

·
Registered
Joined
·
33 Posts
Discussion Starter · #1 ·
Finally got the mods complete which include the 3.10 pulley, Amazon Racing CAI, Diablo chip, and Bassani xpipe and cat back. After driving the car the grin factor went up significantly. The sound is loud but under hard throttle that thing sounds sweet. It is habit forming!!!! Now the disappointing chapter, took it to the dyno today and did not get the results I thought I would. The car dynoed 358hp/358tq stock and the best pull today was 427hp/429tq. Yea, I know, what am I complaining about but this is basically the same tune as Jimmy V and others and I was really looking for that 440 to 450hp range. The 427hp/429tq was the first run and it did not get any better, matter of fact it fell off to 416hp on second and 419 on the third. A/F also bothered me as well, fell to 13.5 at 3000rpm stayed flat till 4300rpm then fell to 12.5 till 6500 rpms. Comments, observations
 

·
Registered
Joined
·
2,736 Posts
Very good questions, I would like to know also, this is all making me nervous for when I purchase mine, hope to god there is not this much difference between all 03 with the same mods, I will be hoping I get a ringer!!
 

·
Registered
Joined
·
510 Posts
Sounds like the A/F is a bit lean. It should be around the 11.0 - 11.5 range
 

·
Registered
Joined
·
2,573 Posts
SVTVenom said:
Sounds like the A/F is a bit rich. It should be around the 11.0 - 11.5 range
You mean LEAN. He said that he's at 12.5 at 6500rpm.

MJ
 

·
Registered
Joined
·
510 Posts
mjchip said:
You mean LEAN. He said that he's at 12.5 at 6500rpm.

MJ
My bad, college homework is driving me insane!!!! :eek:
 

·
Registered
Joined
·
87 Posts
mjchip said:
You mean LEAN. He said that he's at 12.5 at 6500rpm.

MJ
True, but based on my understanding of A/F ratios, it should make more HP closer to 14.1 (stoich), assuming you can keep it from grenading, so the lean A/F shouldn't be costing him any HP. Would you agree with that MJ, or am I off here?
 

·
Registered
Joined
·
2,573 Posts
NetworkingGuru said:
True, but based on my understanding of A/F ratios, it should make more HP closer to 14.1 (stoich), assuming you can keep it from grenading, so the lean A/F shouldn't be costing him any HP. Would you agree with that MJ, or am I off here?
Exactly. In general, the leaner you go the more power you'll make....up to a point.

MJ
 

·
Registered
Joined
·
510 Posts
Shows how much I know about A/F :p I'll leave it to mj, he's a pro ;)
 

·
Registered
Joined
·
189 Posts
Hey oneSVTfan:
Try not to get hung up in other peoples numbers. It is easy to make that mistake) All dyno's can vary, depending on load factor setting on the dyno.. etc..... Jim's car did make the numbers you refered to, however he has a Mac cat back, while Mac may not look pretty, nor is it Stainless Steel, it does produce some serious HP/Tq. Jim also has an aftermarket T/B- and at the time you are refering to it was a Pauls High Performance unit, (I think he is selling it? He just got an Accufab.)

I think the A/F is good for your boost level. Lean is mean (you can also break sh*t lean), but again your boost level will keep you ok in my opinion. Did you hook up a scan, if so what was the timing? Manifold temp between the first and second run? Did you say Rick did your chip? If so, send him your dyno sheet. He helped me a ton.

What I find interesting about your post is your second and third pulls. I had similar results, did you cycle your chip before you put it on the dyno? I did not, but wish I did, my readings would have been more accurate, I think. Hang in there..
 

·
Registered
Joined
·
2,573 Posts
BlownCobra said:
Lean is mean (you can also break sh*t lean)
Being of the conservative ilk, I like "Fat is where it's at!" :D

MJ
 

·
Senior Member
Joined
·
400 Posts
We have to add some fuel for you. Did you drive the car for a few driving cycles before the dyno? Also did they use a bung or tailpipe? Let me know and I'll take care of it.

Rick
 

·
Registered
Joined
·
88 Posts
On most natiurally aspiratd cars the closer to stoich. range for a/f is better for hp. But these blown 03 cars like extra fuel. That is where the dyno tuning helps. When i had mine done at JD's we started out with about 13 to 1 and kept making runs each time lowering the a/f. Finally we got down to about 11.7 to1. Tried to get lower but ran into the stock fuel system limits I think. The fact is though that every time we made it richer it made more power, which goes against normal thinking . At some point going richer should cause it to lose some power, but we never hit that wall yet. Every time we went richer we made more power.
 

·
Registered
Joined
·
50 Posts
Those are great numbers! I had a lean condition, I was running 18:1 @ 3000 RPMs before the MAFterburner. On lean I ran a best of 439.5 HP / 388 Torque. After tuning with the MAFterburner, my A/F got flat at 12:1 - HP dropped to 428ish but Torque went up to 405. It was hard to get acurate numbers as I made 12 runs to tune, and my engine was suffering from hear soak. The best part is I gained 50 or so Torque from 2500 - 3500 RPMs over the lean runs. I would say you could run where you are, but if you want to get better peice of mind I would bring it down to at least 12:1. You will loose a little HP, but should gain some torque.
 
G

·
Note on the Bassani..you will notice that its rappy when you let off the exhaust after getting on the car or hitting the gas...With the Bassani Mid Length Headers...it smooths that right out..just an awesome sound...nice and smooth. Just figured I would tell you that....just incase you dont like that rapping sound on let off. Hopfully the Headers come out soon for all of us.

Harry
www.HotRodHarrys.com
 
1 - 15 of 15 Posts
Top