This is relating to my attempts at having my new setup tuned on the dyno with a wideband O2 sensor. I went to a local person who is very well established in this field. He has been a contributor to Corvette Fever and GMHTP. I've already spent $300 for dyno time. We did a baseline dyno test using a file he downloaded (I'm not sure where) that comes from an 89 Vette Auto w/3.07. The car runs better with this than stock, so we took data using this chip. This chip is what's in the car now. We saw the the AF ratio at WOT was 17-1. We are using stock fuel pressure with 24lb ford injectors. He found that when he attempted to change customize the program, he found that the parameters he was looking for were beyond that available with the chip. His attempts didn't idle at all and set off the check engine light. At that point he suggested that he download the file to Superchips (he's a modem dealer) and have them modify the file. When he spoke to them, they suggested that I go out and buy an 89 chip so that they can identify the chip using the four letter code and then baseline it again. From there they would provide the custom program. We have now estimated that the new chip will cost me $400 and at least another 3 hours of dyno time at $100 hour. So I figure when it's all said and done it's going to run me about $1000. While I budgeted about this amount, I feel a little wary about spending this much money given what has happened so far.
So my option are : 1. Press on and do as he says, 2. Call Ed Wright or Formato and get one of their chips. Obviously, I'd be thrwoing away the initial $300 I spent already.
What would you do?

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Neptune, NJ
White '87- 383 Superram ported and matched to TPIS big mouth intake, Eagle cast crank, 6"eagle forged rods, srp/je forged pistons, LPE 219 cam, ported heads(2"x1.56" ferrea valves), Comp cams pro-magnum 1.6 rr's, double springs, titanium retainers,Hypertech power coil and cap, 4 bolt block, TPIS headers, auto(trans kit,shift kit),Pro Torque 2600 stall converter, k&N filter, 3.07 rear diff., Silver ZR-1 wheels 17x9 and 17X11

 

I'd say "FVCK it" and get my own PROM burning equipment and do it myself. Grab a stock '89 vette image off DIY-EFI and then change whatever you need to change yourself.

For example - If you are running 17:1 at WOT then tweak the WOT PE vs. RPM table to put you at where you need to be.

If you leave this up to others then they will rape you (intentionally or unintentionally).

Example - I spent 3 hours programming a '91 vette this weekend (FOR FREE!) and we had that baby idling like a champ, removed an off-idle surge, and the car no longer runs at 108 BLMs (very rich!) ... among other little stuff like timing changes, constant changes, etc.

$1000 is way too much to pay for a custom EPROM. Hell - with twice that amount you could buy a SpeedPro unit with a wide band O2 sensor that basically tunes itself.

Tim

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TRAXION's 1990 IROC-Z
Best Time = 12.244 @ 112.51mph (1.778 60' / 7.819@88.32mph in the 1/8)
All Natural. No Force. No Drugs. Stock Bottom End. Stock Body Panels.
Gunning for NA 11's with bigger cam, bigger stall, and bigger exhaust.
-=ICON Motorsports=-
Moderator: PROM board at thirdgen.org

 

You make perfect sense. Unfortunately, I do not have the time or skill to do the programming myself. Could I learn, yes. Probably take me months. I've learned alot here by lurking in the shadows, but now is not the time for me to experiment. I sunk a ton of $$ into this motor and I want to make sure I don't screw it up.
I appreciate what you've pointed out here. I'm thinking about calling Ed Wright and just ending this once and for all.


[This message has been edited by GlennS87 (edited March 19, 2001).]

 

Speed pro just tunes to what you say. You have to still figure out what the engine wants, so there is no difference, even after spending about $2,000.

Shoulda been here for the powwow... We wound up dong a bunch or chip work and plug reading.. Doc and the guys were secretly feeding me info., so I think we got it right LOL