posted in generel, meant to post here..

Welp..My Car is done....I just got off the Phone with Mike at J & M.....I don't know what to say......He said the car runs excellent...He fixed the timing...and added the 42lbs injectors and if you remember my Dyno Graph(see below) It looked like crap..I was making 361/379...Welp now he tells me the car is making 340rwhp!!!!!!WTF!!!!!!!!!!WTF!!!!!!!!!!! !!!WTF!!!!!!!!!!!!!!!!!!!!!!!!...But the Dyno is All smoothed out.....He told me not to go by the Dyno... the car pulls really hard and runs smooth....And that my First Dyno was spiked..i was getting power but then it would drop and then get up again...and drop off.....I don;t really know what to say.....I'm beyond PO'd......$7500 for 80 horsepower.....I'll post the new Dyno Sheet later when i pick up the car today......He was new to the Software and new to editing the Lt1...Can this possible be right? 340rwhp is the best i can get with an ATI PC-S1...why in the world are Stock Camaros and Firebirds making 400 at the wheels with Prochargers...I feel like crying <sigh>

 

not sure dyno's don't allways read the same ,so wait till you drive.

 

The car drove fine before the tune i had no complaints other then my power was lower then i wanted, expected and advertised....I brought in for tuning to GAIN power not to loose 20ponies

 

Are you still running a stock fuel pump? Something doesn't sound right. I know this is an apples to oranges comparison, but on my old mustang (88GT) I added bigger injectors and fuel pump, ditched the FMU, and had a chip tune and gained 40hp / 26 tq to the rear wheels.

Ideally, you should have gained power or stayed near the same (with an optimal tune).

 

Well i just came back from the shop....He said the car is not showing the true horsepower because of the 2.59 gears...He showed me a graph ....he had the car going 155mph on the dyno.and it still wanted to go..He said If i added 3.55's he would be able to show me the HP i wanted,,but the 2.59 are not letting him get the numbers down on paper.....Car seems to run better..he changed the shift points to shift about 5mph difference....Fans come on sooner...Temps didn't go above 215 going through Hartford Rush hour traffic where normally they would be 235....The Boost.....the boost is wierd and even Mike saw this....I can get 10psi off the line.....And He had it at 11psi on the street when he drove it...But the boost even more constant now..He sayed while its good boost...its not good to see all the time.....Anyways ...I don't know what to think....The car seems to pull the same as before.....The Dyno showed 334rwhp and 381tq...but he said do not go by those numbers.....<shrug> o well.... i don't know what else to do....or think.....

SKI HELP ME!!!!!!

O and yes i am running the stock fuel pump...

 

Isn't Procharger any help? Seems like they should know something about them, since they build and sell the things. JMHO

 

I have no supercharger/dyno experience. I can suggest running a datalog. It will tell how close the tune is. Ive spent several Saturdays at the dragstrip and tuning for the best et and mph ,followed by a datalog to get the most out of my car.

 

I know a guy who put a Procharger on his Mustang with the Fuel Pump given in the kit which was bigger than the stock unit. Car was starving for more had problems getting the HP he had hoped for. Installed a larger Fuel pump and straighten out his problems car gained 40 HP and ran like the monster it was supposed to be. It worked for him and the best is the kit from Procharger gave him the fuel pump??? and he had to go bigger, they should know this when they put these kits together???

 

if you have a fuel pressure gauge that you could tape to the windshield and make a full run and watch to see if there is a big drop off?!?!

 

you might get more ideas in the FI/Nitrous section, wouldn't you?

 

I would be dissapointed. To be honest, I was leary of the shop you chose from the beginning of your posts about supercharging. I wouldnt, however, put too much emphasis on dyno numbers. Dynos vary, its a known fact. Take it to the track and see what it runs.

The part about losing 20 HP is garbage though. Your tuner should have left the settings in that area alone, and tuned other parts of the fuel/spark curve. You couldve had a "smoother" tune AND kep the 20 hp. It sounds like you may need a new tuner.

You said you have a stock pump- does it have the ATI pump also? They include a pump in thier kits that installs inline and boosts pressure. If all you have is a stock pump- thats a problem. If you have the ATI booster pump, its still not the best. The better way is to replace the in tank pump with a 255lph unit, and ditch the booster. Check behind your liscence plate- thats where the directions said to put my booster pump.

If your not running enough fuel pressure you will lose HP. Even worse, is that with larger injectors, low pressure will create a poor spray pattern too. This *could* be part of your problem.

Really though, take it to the track. The only numbers that count are track times. Let us know the ET, MPH, and weather conditons when you go. MPH is the true indicator of HP, and it doesnt lie. Dont worry about tire spin, or reaction time as these have little to no effect on MPH in the quarter.

One last thing- your axle ratio has ZERO effect on your numbers from the dyno.

 

Another thing is he charged another 300 dollars this time for the lt1 edit tune, and he charged me 300 dollars for Dyno time the first....I have 7600 dollars invested in this and lame numbers to show for it..I know the dyno numbers aren't the whole tale of the car...but for that kind of money you wanna SEE results......I might bite the bullet and pay for my 3rd tune at Vette Dr if they are willing to look at someone elses mess.....

 

Recently I spent 4 hrs at the dyno and the owner was not able to tune my car and he still charged me 3 hrs @ $125 per hrs. Put back my old eprom and made 2 pulls cost me total $405 and 544rwhp untune.

He say because of your 2.59 gear that is why it don't shown true hp? that is BS I have ever heard. Your 2.59 gear has nothing to do with your hp out put. The reason that the dyno did not hold or show the hp is because I think I know the answere but I 'll let you guy guess it.


Bruce

 

MAN! For that kinda money, I could have worked on your vette AND got you results AND had money for airfare!
10psi at barely any throttle sounds strange...

 

Different gear ratios will not change the amount of HP your engine produces. Sure if you wanted to have an inflated HP curve you could neglect to correct for it. I'd be concerned this guy does not know as much as he advertises.

Oops... Missed Bruce's comments, but now you have two people telling you the same thing.

 

try these guys for help

www.pcmforless.com

 

LT1vetteguy.

First off I will say it again, don't get hung up on dyno numbers. Dynos vary (Alot) and should only be used to see changes and gather shift point data.

Second, I just browsed through the posts, mainly yours to gather information, but the gear ratio has nothing to do with the dyno numbers so that is a little stretched.

Third, I would suggest that you go to the track and get some number for your car. Record the MPH your car traps at, and then get cars weight. From those two you can determine very accurately what your putting down in the power department.

Few other things. I tuned a guys pro-charged setup last spring. The car ran excellant and ran 11s first time out with very little traction. One thing about your boost this guy learned and did not know why this happened until I explained to him. He reported on the stock vette heads, with the SC before I tuned it, it ran MUCH more PSI. He then put AFR 190s on the car per my recommondation/SR and the PSI went down. He was concerned when he came for the tuning that something was not working right. I explained that the heads are LESS restrictive, therefore the PSI dropped some. Before the heads were acting as a restrictor, raising the pressure.

Perhaps that is what your seeing. But reading it almost sounded like your getting that much PSI at idle? That is not right.

Few other things I would like to add. Not sure from your signiture what compression your running. But with a SC setup, if your running stock compression, its going to kill the potential for the SC. You should really have your motor setup for about 9-9.5:1 compression n/a, then put on the charger. Your gains would be substantial. When your already at 10.5:1 n/a and you put boost to it, your playing a dangerous game. Which leads me to my next point.

Are you running the knock sensor. That jagged graph is very indicitive of timing fluctuations. Is is possible your getting knock, and its pulling timing? Any datalogs?

 

Get ahold of Dez Racing in Seekonk, MA. Mike Dez does a ton of Procharger installations and has a tuner that works for him that is good with the Edit stuff. LS1 and LT1. He recently did a Procharger installation on a CF members LT4 car and the customer was extremely happy with the work. You'll probably be able to do a search and find the thread

 

Ski, my Engine is all stock except the plugs and wires.....Then the SCer and Corsa exhausts and now the 42lb injectors...I have the new Dyno At home i will post it..it has the AF Ratio as well...He said the car was detonating like crazy and getting knock and throwing timing..and he fixed all that...he also said he has it running alittle rich..By all means i would love it if you would call him and ask him what the hell was going on with my car and maybe i can get some answers..for real lol....Mike @ J & M 860 645 6389 ask him what was going on with Scott's 1994 Auto SC'd vette..maybe he can explain it...the new Dyno does not look as bad as the old one but the numbers are crap..and the it still alil spikey... I know i should take it to the track and stuff....i will when i get a chance....but for now just to be satisfied for the money i paid..i would like to see numbers on paper....

The 10--11psi is coming from flooring from a dead stop..btw..not idle

 

<SIGH>...Well i called The Vette Dr's and the guy didn't even know if they had the stuff to tune a Lt1...he said 95% of the work they do is LS1's.....He did say he was worried about the boost it was making he said even 8psi is too much and getting up to 10psi is very dangerous because it will crack a piston.....He is wondering if maybe i cracked one already and thats why the lack of power is there..he said to check to see if the dipstick pops off and smoke comes from the cap...The car drives fine...but i will have to check after i get out of here for those symptoms....I think i am screwed here so i don't know what else to do....But as far as tuning he told me to call back tuesday to when his partner comes back.....He did recommened me calling ECS, but i remember talking to them and they won't even work on C4's anymore......