I will be getting my car dyno tuned tomorrow by a really good tuner. He is very highly recommended. I will post some pointers and my hpt files when its done. We are starting with the gm reflash. I want to set it up so it doesnt lower afr with rpm but rather the boost pressure like a normal turbocharged car. The dyno owner calls it the fuel map from hell. I will keep you posted on how it goes.
Your stock PCM uses APLHA-N (TPS vs RPM) and not Speed Density (MAP vs RPM) for its fuel mapping, HPTuners cannot change this. You can still do some tuning but because there isn't a direct correlation between TPS and boost this will definetly be a little tricky. This is the #1 reason why I choose to go with Megasquirt over HPT, although HPT definetly has its advantages too.
We're working on 95 code that might be able to do this. When we get the 95 pcm figured out that is. It shouldnt be too hard to remap the sub to a diff table.
In the mean time, i would go with megasquirt.
Helimech wrote:Your stock PCM uses APLHA-N (TPS vs RPM) and not Speed Density (MAP vs RPM) for its fuel mapping, HPTuners cannot change this. You can still do some tuning but because there isn't a direct correlation between TPS and boost this will definetly be a little tricky. This is the #1 reason why I choose to go with Megasquirt over HPT, although HPT definetly has its advantages too.
And yet there's this.....
sig not found
hmm first time I saw that chart, is that from a s/c reflash? That would definetly aid in tuning a Turbo'd car but I still believe that a true speed density system would get you better results. Interested in seeing his results either way.
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hmm first time I saw that chart, is that from a s/c reflash? That would definetly aid in tuning a Turbo'd car but I still believe that a true speed density system would get you better results. Interested in seeing his results either way.
Why is this not speed density tuning? This will multiply the 100 kPa entry for a specific RPM by the multiplier obtained from the table above. Think about a VE table accessed by MAP and RPM... pick any one MAP column in the table and all others are a percentage of that column. With values above 100 kPa you can sacrifice resolution and fine tuning and use a simple two dimensional multiplier.
It'd be nice to know whether or not this table exists in all year calibrations.
-->Slow
Just got back from the dyno. To get things started, last month I went to a baseline dyno day in CT with Illd9 and others from nejbody. That day I had my boost set around 8-9psi running the supercharger reflash with gm supercharger injectors. It put down 208 hp and 217 tq. at a very lean 13.74 peak afr. I then decided before i blow up my engine to buy hptuners and 48# injectors. Finally got it on the dyno. It was strapped down for about 5 hours. The guy tuning it has been working with hpt for a while now on f-bodies, corvettes, etc. and is very knowledgeable. He tunes powerplants that make hundreds of thousands of HP for a full time job. First we got the idle and drivability tuned. He used no math to get the injector constant. none of the math made any sense, so he tuned by trial and error. the stock constant was .32359. we ended up at .27428. Now she idles mint with a 14.7 afr. Next he started tuning the drivability by editing the Low RPM Dbl and Low RPM Sgl VE tables. Raising the number will give more fuel and lowering will take away fuel. This is done by data logging and comparing afr vs rpm vs kpa and adjust these tables accordingly. At this time he changed all the timing tables. We started with the GM N/A timing tables because the reflash pulls way too much timing at all the wrong rpms. There is now a perfect timing curve and no knock whatsoever. Finally the fun part Power enrichment. First he messed around with the PE Base AFR vs ECT. This table is based on Lambda not the standard AFR. He set it to 12.0 at full operating temp. Next he changed the multiplier going from .96875 at 4000 rpm to 1.28125 at 4000 rpm. He changed other rpm columns too but that is too many numbers to post. Now we have a descent afr around 11.9. Next all the fine tuning is done in the high rpm ve table. Again the higher the number the computer will give more fuel. Finally after a few more runs we got a nice straight line of 11.8-11.9 afr across the board. Then I turned up the boost to about 11-12 psi. Now time for the numbers. First run was running really rich at 10.0 or lower across the board due to the large injectors. It put down 179 HP and 210 Tq. About 15 runs later and about 20 computer flashes it put down 223 HP and 252 Tq at 11.8-11.9 afr across the board. WOW what a huge difference. It feels like it has so much more power. My friends Stage 2 SRT-4 put down 237 HP and 253 TQ. You can use that for a comparison.
Good to hear it worked out for you, did the tuner have any comments on tuning the J-body vs others?
slowolej wrote:[Why is this not speed density tuning? This will multiply the 100 kPa entry for a specific RPM by the multiplier obtained from the table above. Think about a VE table accessed by MAP and RPM... pick any one MAP column in the table and all others are a percentage of that column. With values above 100 kPa you can sacrifice resolution and fine tuning and use a simple two dimensional multiplier.
It'd be nice to know whether or not this table exists in all year calibrations.
-->Slow
As to wether or not you can call this setup a "true Speed density" system, I'm not sure really. The multiplier table definetly adds something I never saw when I was looking at HPT, if its only with the reflash then it wouldn't apply to myself then anyway
I would have to sit down and really plot it out to see if the multiplier left any gaps vs a speed density system for Turbos. Remember though the stock VE table is TPS based and not MAP, but the table really does add an extra demension.
He didnt touch that table. He only used the ve tables which work on rpm vs map. He can usually do an f-body in about 2 hours and this took 5 hours. It was the first j-body hes ever done.
Hmm, I'm confused then as the only VE tables I have seen were TPS vs RPM, except the idle table. Also the timing Map is MAP vs RPM.
Helimech wrote:Hmm, I'm confused then as the only VE tables I have seen were TPS vs RPM, except the idle table. Also the timing Map is MAP vs RPM.
The N/A program it tps vs rpm and the supercharger reflash is map vs rpm
awesome.
thanks for posting the info. all though it dont relate to me as i cant use hp tuners on my cav, but it was a great to read what went on with your cav.
Team GREEN
I'm glad to see someone gewt some dyno tuning with HP. have you thought about going a little leaner on the AF? Low 12's? SO the final hp number was on 11-12psi?
FU Tuning
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He can usually do an f-body in about 2 hours and this took 5 hours.
Hope you got a smokin deal on Dyno time.
-->Slow
The total cost was $575. The owner had to get paid for dyno time and the tuner gets his cut from that. The tuners name is Kevin Hagerty. he works independently and comes into the dyno shop when owner has a gm car to be tuned. This guy really knows his shat.
what if anything was done to the timing maps? as that is an oft-ignored factor on this board, it would probably be good to shed some more light in that area also. Good info though, glad to see there are people on here willing to spend the money to do things right and reaping the benefits!
Arrival Blue 04 LS Sport
Eco
Turbo
Megasquirt
'Nuff said
he started with the N/A timing map and then pasted in the boost part of the supercharger map into it and blended them together.
$575 isn't a bad price.
Independent tuning can be profitable. I did it while I was going through school. I haven't heard that name but I'll keep an ear open for it.
Which dyno?
-->Slow
I'll vouch that those multipler tables work wonders. I accidently typed a 0.50 instead of 1.05 at 180kpa, car drove great, then leaned out to hell and died, that was the first thing I checked and fixed, and it went away.
What size turbo are you running?
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
Now I'd hate to be in your shoes...which car to drive? I'm assuming both are loads of fun now. Those numbers are crazy, deffinatelly worth the time and money though. A J running with a SRT4, was quite a strange thought a few years ago.
I am basically running your tune and wow my car came alive. Huge iimprovement, I have much larger injectors and changed the dan speeds but aside from that, it got rid of most my knock, I think I might have a collapsed lifter, so that is nect on the list now, thanks for posting, it really helps.
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
I am showing that it is not an approved download yet
Jason
99 Z24
Racers Edge
Johnny Mack Turbo Systems
Engineered Performance
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
