TCCoA Forums banner

1 - 20 of 20 Posts

·
Registered
Joined
·
2,577 Posts
Discussion Starter #1
I took my '95 stocker down to Miami on Saturday for an SCT (Jerry) dyno tuning session. The only engine "mods" my '95 has are 22-c plugs and a 180* T-stat. The only drivetrain mods are a J-mod shift kit (with the bottom springs intact) and the 3.27 closed pumpkin from GB I swapped in for the 3.08 original equipment diff.

The results of the tune were interesting.

Here is the baseline graph:



The baseline was done with the speed limiter off to eliminate downshift, but the TC was not locked through the EEC, it locked up mechanically as it normally would - hence the big TQ spike early on... Note that the TQ spikes and falls off throughout the band. Note also that the HP "curve" is pretty much a straight line, even "concave" a bit from 2500 to 4500. And the A/F... can you say "roller coaster"???.. can you say "lean"????



Here is the graph after Jerry let his fingers do the walking through the EEC:



This pull was done with the TC locked. Now some of you out there may say, "heck he lost power" because the peak numbers are a bit lower. But careful examination of the shape of the TQ curve shows that there is an obvious gain across the whole power band and the peak is right where you want it to be, just below the shift point. Because of the difference in the scales used from graph to graph (don't ask me why???) the HP improvement is a little more subtle to see, but there is obviously a bit more "curve" and no "concave" shape at all. If you compare the HP numbers at 2500, 3000, 3500 and 4000 you will see a pretty dramatic increase in the HP available at those rpm ranges. Much more power under the curve throughout the power band. And the A/F.. can you say "flat line"??? not too fat, not too lean, just right.....

Also with regard to the peak numbers, the actual numbers of the first pull are suspect. My experience with GB has been that whenever I dyno-d on a set up that can't lock up the TC, the numbers are skewed a bit higher compared to pulls with a locked TC...

Now a little bit about the software Jerry used. It was the identical software that is availbable with the SCT software/hardware package.. He started with a base file that is available to anyone with the package and then proceeded to alter values, exactly the same as you can do with the consumer package. After he was done on the dyno, I took a test drive and had a bit of a driveability issue. I had a little pinging in OD at low load between 1200 and 1500 rpm. When I approached a red light or stopped traffic and idled down, if the light changed or traffic moved, when I accelerated up (without downshifting) there was a hint of detonation. Well, no problem. I went back, and one of the SCT guys pulled a little timing from the 1000 - 1500 rpm range and solved the problem. I watched him do it, it was easy. He just highlighted the rpm range he wanted to change and entered a different value.

The tune deffinately made a difference in the performance of the car. She accelerates all the way through the gears. I get a chirp in the 1-2 shift under certain conditions, and even after the J-mod I didn't have that. The last time I ran the '95 my best time was like 16.1. I'm going to the track Friday nite with the '95, I'll have some hard numbers to post on Saturday...
 

·
Registered
Joined
·
2,577 Posts
Discussion Starter #3
The Great Obucina said:
so, when am i runnin ya?
joseph
I'm sure we'll hook up on Friday. I'll be running in the 15's bracket....
 

·
Registered
Joined
·
9,966 Posts
96 GoldBird said:

I'm sure we'll hook up on Friday. I'll be running in the 15's bracket....
off topic, can your tire guy get Firestones?

joseph
 

·
Registered
Joined
·
3,178 Posts
That TQ spike at the HP peak skewed that #, but I'd say w/o it you'd be at about 215... the HP looks like it'd be about 165 on that pull too. Nice gains!

Are all of our OEM WOT air/fuel ratios that squirrely? That's all over the place. Makes me a bit nervous. lol. This tuning is my next mod after I get the gears I bought in... It'll be the best $ I spend on the car. Thanks for sharing the info :)
 

·
Premium Member
Joined
·
2,725 Posts
Another person having fun at the dyno! I spent the afternoon with mine on the dyno also. If I only had ‘more friendly’ gearing in the rear it would help.

It is making 187rwhp and 287rwt but that still leaves me at 16.0 with
The 3.08’s (but darn if it wont do 145mph!):D

I wonder how much weight I could loose before this weekend :leftright
 

·
Registered
Joined
·
2,936 Posts
I want to see what she runs. Be sure to post that after the mini meet. That air/fuel curve (before tune) makes me wonder how safe it is to get on it with a stock tune. You can't help but mod whatever car you have in your posession huh? Are you going to shoot for mid-14's before you get GB back? :)


Russell
 

·
Registered
Joined
·
2,577 Posts
Discussion Starter #8 (Edited)
96bird said:
IAre you going to shoot for mid-14's before you get GB back? :)
Russell
Why stop at 14's??? I will have all of GB's cast off bolt ons (GT MAF, CAI, Steeda pullies, '96 lower intake, pnp upper intake, 75mm TB). A set of PNP NPI's and Compcams and a PI intake.. or PI heads and Intake... a Mark TC..

Seriously, right now the car has 40,000 original mi and I've been driving her since she was new. She's is a cream-puff and her value right now is in her stock condition (well almost). As tempting as it is, I'm gonna leave her alone for now. I can store the parts for later.

Somehow I think I will probably be able to get my 'speed' fix from GB, and driving a stock MN12 will be a relaxing change of pace.
 

·
Registered
Joined
·
4,205 Posts
I guess he tuned it a little too good then:D Those are some nice numbers, get a new tranny in there, and let us know what it runs.
 

·
Registered
Joined
·
2,577 Posts
Discussion Starter #13
RichardM said:
So was that with the factory intake resonator in place????
rm
Yes. The only "mod" other than what I listed in the initial post was a K&N OEM replacement filter in the stock air box - violin case intact, untouched.
 

·
Super Moderator
Joined
·
11,961 Posts

·
Registered
Joined
·
2,577 Posts
Discussion Starter #15
guitar maestro said:
very nice...almost identical to my dyno sheet, except my stock A/F wasn't all squiggly...it just plummeted down after 2.5k RPMs
The 'before' hp and tq graphs are almost identical.. the same little concave thing going on with the hp, and the same drastic drop with the tq..

Based on our two AF graphs, I think it's safe to say that the stock tune is less than consistant from car to car and screwed up... looks like you were throwing away alot of fuel...

Yours is a '97 and mine is a '95 EEC, so I'm sure there is a difference in the factory tune to begin with. I didn't catch it all but Jerry said something about my EEC... Something like "... it's one of the old ones, you don't see many of them around." Maybe someone can enlighten me with what that means. It may account for the erratic AF and others may not have to worry about that issue.
 

·
Registered
Joined
·
169 Posts
Here's yet another almost identical set numbers. I only had a larger MAF, plugs and stat.

 

·
High-Mileage 4.6L Thrasher
Joined
·
3,232 Posts
96 GoldBird said:

The 'before' hp and tq graphs are almost identical.. the same little concave thing going on with the hp, and the same drastic drop with the tq..

Based on our two AF graphs, I think it's safe to say that the stock tune is less than consistant from car to car and screwed up... looks like you were throwing away alot of fuel...

Yours is a '97 and mine is a '95 EEC, so I'm sure there is a difference in the factory tune to begin with. I didn't catch it all but Jerry said something about my EEC... Something like "... it's one of the old ones, you don't see many of them around." Maybe someone can enlighten me with what that means. It may account for the erratic AF and others may not have to worry about that issue.
He's talking about the old 88K EEC module.
JL
 

·
Banned
Joined
·
1,162 Posts
yea my a/f was a smooth curve but rich as **** with stock regulator then i add the aeromotive adjustable regulaor and it's perfict and i have about the same numbers as him with a stock tune i get my chip inacouple of weeks
 

·
Registered
Joined
·
2,577 Posts
Discussion Starter #19
Johnny Langton said:

He's talking about the old 88K EEC module.
JL
Ah-ha... thanks man...
 

·
Moderator, Red Sox Nation Rabid Fan, TCCoAAC Found
Joined
·
3,165 Posts


That is just with the J-mods, Pulleys, Gen II Chip, T-Stat, Paper Filter... FMS Wires, and 22c's. Stock exhaust also and Stock MAF.... Pretty similar to everyone else's... Still Running the Gen II also till April:D BTW that isn't after his tune, just his chip...
 
1 - 20 of 20 Posts
Top