I had the Fiero Dyno tuned today, I’m happy with the results. Charles from DHP was in town for some tuning for the Grand Prix guys and I was invited along. (Thanks Lee) What I was looking for was a few unwanted SES codes removed (evap, tank pres. sensor, egr, random misfire P300) and maybe a few more horse. The dyno time was cheap, I got 45min for $50 (70/hour), which I think was 5-6 pulls. Since I traded parts to Lee to cover the cost of the tuning, so was Charles. ;-) Big Thanks to Charles!
Setup: ’86 Fiero GT · 3800 Series II Supercharged Engine/Tranny 4T65E-HD Swap (1998 Grand Prix GTP) · ZZP Stage Two Intercooler · ZZP Machine Intake Manifold · ZZP Throttle Body Spacer · ZZP Stage 1 High Velocity ‘99 Throttle Body · Comp Cams VS Cam (ZZP) · The Other Guys Exhaust Headers · Digital Horse Power (DHP) v1.0 Reprogrammed PCM (before tune) · ‘92-’95 Pontiac Bonneville Fuel Pump · Drilled 180* Thermostat · Taylor Custom Spark Plug Wires · Thermo Tec Thermo Wrapped Crossover · Tri-Power Tri-Collet 2.8” Supercharger Pulley · K&N 7” Cone Filter · Custom Exhaust · EGR Deleted
I had almost run out of gas a couple days ago and had to roll into a gas station on fumes, all they had was 91 octane. I forgot about it until my car was up on the dyno, so the tune was done with 91 octane.
Results: 291.3 HP | 366.9 ft/lbs Torque | 12.8-12.6 A/F | (no knock, as far as I know)
Overall change 2.6 HP and no more SES light. The torque figure was at about 3500 RPM, I believe the max torque is at slightly lower RPM, looking at the chart. Although 366.9 ft/lbs is still a good number. Since the charts I have start at a different RPMs I can’t really judge the torque difference, but it feels stronger down low. I believe he bumped my timing by about 4-5*.
Even Charles was surprised that the v1.0 DHP PCM was as close as it was.
After I got back yesterday from the dyno, a friend of mine was in from out of town to show me his WRX and he wanted a ride. I always roll the throttle off the line to eliminate wheel spin, but my friend wanted to know what would happen if I used a power brake start. I expected to leave big black mark(s) (no lsd) for a few seconds and then go. I’m not sure if it was as much the Dyno tune as the new drag radials, but this time something different happened. There was something new, the front end rose like usual, but this time as it came down it made a soft thump noise in the front end. I did it twice, and the only thing I can assume is that I’m lifting the front tires off the ground. I’ll see if I can get a picture of it in a few days. I’m not saying I want this to happen and once I drop it, I’m sure it won’t happen anymore, but it was kind of neat. Torque is Awesome!
IP: Logged
01:01 PM
PFF
System Bot
MNFiero3800 Member
Posts: 287 From: Webster, MN, USA Registered: Nov 2001
Just a little curious about if you have any other minor mods... I would have figured you would be pushing over 300 with the listed mods and an IC...
I'm having the DHP PCM in mine along with a 3.4 pulley and CAI, etc...
Keep up the good work and congrats on the times and power
I think the numbers are right in line with what they should be, even a little high. You have to remember that these numbers are at the wheels not the crank. For crank HP you have to figure about 20% drivetrain loss.
[This message has been edited by MNFiero3800 (edited 05-23-2004).]
By the way I'm not sure of the peak torque gains because the dyno charts started a different places and not low enough to see peak torque. The low torque one started at 4300 and the high one at 3500. Looking at the charts, the over all torque gain seemed not much more that 2-3 ft/lbs. Although neither chart starts low enough to compare peak torque numbers. But the weird thing is it feels stronger all around.
Just my observation, I could be wrong.
IP: Logged
09:49 AM
MNFiero3800 Member
Posts: 287 From: Webster, MN, USA Registered: Nov 2001
Post from Charles (DHP Tuner) on ClubGP on this topic:
quote
ORIGINAL: mnfiero Although neither chart starts low enough to compare peak torque numbers. But the weird thing is it feels stronger all around.
quote
ORIGINAL: beyerch Heatsoak.
These cars get hot fast. While the graph only shows a new best gain of ... 2 - 3 HP, you gotta remember that best came on what run 5 or 6? It has more go on the street cause its getting better air and it won't heatsoak quite as bad.
a lot of cars drop at least 10 HP between a cold run and a hot run from my experience. REgardless, the 1.0 was real close for that setup and we didn't find any magic HP like streetrace's car where it went from 310 to 330.
Charles
Interesting, makes sense...
[This message has been edited by MNFiero3800 (edited 05-24-2004).]
IP: Logged
11:17 AM
Uaana Member
Posts: 6570 From: Robbinsdale MN US Registered: Dec 1999
I think the drivetrain loss numbers you came up with are pretty reasonable. Those that have dyno'd just the engine and then the whole car say it's just a shade more than 20% with the 4t65E-HD. Most just use 20%.
If you're going to Rock Falls Raceway this year, LMK so I can make it a point to be there.
A couple questions for you. 1. Did you have to cut your trunk for the TOGs? 2. Are you going to try to sneak past tech inspect without a rollcage? (if yes, fun day or sport/compact day is the day to do it)
edit to say, When your Fiero lifts the front wheels, you'll know. Your steering wheel feels really 'light' . You're really close to it now, but if you just do a little 'chicken walk' i.e. gas, brake, gas again, yours will certainly lift the front.
-Tim
[This message has been edited by TimGully (edited 05-24-2004).]
IP: Logged
01:46 PM
PFF
System Bot
MNFiero3800 Member
Posts: 287 From: Webster, MN, USA Registered: Nov 2001
I think the drivetrain loss numbers you came up with are pretty reasonable. Those that have dyno'd just the engine and then the whole car say it's just a shade more than 20% with the 4t65E-HD. Most just use 20%.
If you're going to Rock Falls Raceway this year, LMK so I can make it a point to be there.
A couple questions for you. 1. Did you have to cut your trunk for the TOGs? 2. Are you going to try to sneak past tech inspect without a rollcage? (if yes, fun day or sport/compact day is the day to do it)
edit to say, When your Fiero lifts the front wheels, you'll know. Your steering wheel feels really 'light' . You're really close to it now, but if you just do a little 'chicken walk' i.e. gas, brake, gas again, yours will certainly lift the front.
-Tim
I'll try to post if I'm heading to Rockfalls, I may try to go on a test and tune day though. They didn't even ask my Friend if you had a helmet the last one we went to. Not to metion you get to do the 1/4 mile like hot laps. (as many runs as you want)
I did remove the bottom half of my trunk for the TOG's, I really don't miss it. The result is great for working on the car and nice big place to put tools. It's just flat all the across now, I has enough space for what I need. We just made a $80 grocery run, with no food ending up in the passenger compartment. No huge, but it works.
Since the charts I have start at a different RPMs I can’t really judge the torque difference, but it feels stronger down low. I believe he bumped my timing by about 4-5*.
I’ll see if I can get a picture of it in a few days. I’m not saying I want this to happen and once I drop it, I’m sure it won’t happen anymore, but it was kind of neat. Torque is Awesome!
