Computer chip question - attn Aptin users

[djbartu]

Hey,

From posts on this site, a lot of you agree Apten is the way to go when purchasing a chip for a Gen III. I just have a few questions before I order from them:

What can I expect in terms of real world driving? Will I notice (via "seat of the pants") a little increase in the mid - upper rpm ranges? How about any torque loss in the lower rpms? Any reliability issues? (I need my car every day. No exceptions!)

In a quarter mile, do you think this mod would be worth a couple of tenths? If a stock SHO runs 15.7's, what do you think the same SHO with K&N, Flowmasters, and an Apten w/prem fuel run? (I'll test that this spring at Numedia drag strip.)

And finally, is it worth the $299???????? I guess what I'm looking for, like everyone else, is cheap, easy ways to knock a couple of tenths off at the track.

Let me know what you think.

P.S. The cams are welded and the tranny is stock with 80K.

 

[SHOWHAT9]

There are many choices in terms of people who can burn chips. Apten is one, FPS is another, American Motor Sport is another.
FWIW I recently purchased a chip programmed by AMS. I took it to the dyno a week later. Bear in mind that this is not totally scientific under perfect conditions.
MY HP didn't increase all that much from previous dyno run two years ago - AND I will give you the fact that the sheet was two years old. HOWEVER there is a pronounced increase in TQ in the lo -mid area where we need it the most. IIRC, I'm at work, not at home, so for the moment I can't post the sheet, but there was a 24Ft/lb increase in Torque. That has to translate to something.
In terms of driveability it sharpens up the shifts nicely and does other things to improve overall driveability of the GIII.
I really want to get it to the strip soon to see if this translates into any sort of measurable gain in the 1/4. I will try to remember to edit this post with the two dyno graphs later tonight.
If you want an overall improvement in driveability, the chip is one solution.
Does it increase HP? Sheets say no, does in increase potential Torque? Sheet says yes.

 

[2 4shofast]

I have had nothing but problems with my Superchip that I purchased...I turns out after I had asked...twice....I needed a custom programed chip. I had to replace my computer and still have not solved the problems that were cause from a incorrectly tuned chip :headbang:

I hope you have better results than I did

 

[SHOWHAT9]

I have had nothing but problems with my Superchip that I purchased...I turns out after I had asked...twice....I needed a custom programed chip. I had to replace my computer and still have not solved the problems that were cause from a incorrectly tuned chip :headbang:

I hope you have better results than I did

You don't say if the problem was because your PCM was reflashed, and either the sticker fell off or there was none. I have been told that this is a problem for a very small number of GIII that have tried to get a custom chip. In these cases most of the vendors will want your PCM to get it right. Hope that helps.
FWIW my dealings with American Motor Sports were flawless, and all emails generated responses within an hour. But as I said before, there are many fine vendors to choose from.

 

[Mr. SHO]

I like my Apten. I had some issues initially, b/c the chip wasn't seated right on the PCM. Once I fixed that, the chip was fine. Firmer shifts that never miss a beat. Better response on the 3-2 or 2-1 shift when you are cruising and you stomp the gas. These are the most noticable differences. I haven't been to a dyno or the track ever, so no results there. I got in on a group buy, so I paid less than $299, but it would have been worth the $299 IMO. I rationalize it as ATX insurance, if nothing else.

FWIW, Brian Herron at Apten is a great guy to deal with. I have also heard great things about Alberto at American Motorsport.

 

[2 4shofast]

I called Superchips and talk to them after I installed the chip the first time. They said to take it out and clean the computer again. I tried that but it still had problems finding the right time to shift and it would idle really rough at a stop. I reset the idle and it worked for about a mile and started acting up again. I contacted Superchips again and they said that I need to get a custom programed chip but I am now stationed in Italy and NO ONE knows how or will even attempt ot work on the SHO. I'm not sure what happen to the SHO when it wasnt running correctly but after I took aout the Superchip and installed the new computer it was shifting correctly but misfiring through out the entire RPM range. Any ideas? Now I am forced to drive a 92 POS BMW until I figure out what the problems could be. Im thinking the gaskets for the spark plug wells could be shot but I havent had time to tear it down and see. Any thoughts would be appreciated

 

[Mr. SHO]

2,4shofast:

Try taping a hex nut to the back of the PCM, next to the chip port. It will serve as a spacer and prevent the chip from pressing against the back brace in the PCM socket. I did this and my chip has been fine ever since.

The misfire sounds a lot like a coil pack (or two, or three.) Not cheap or fun to replace, but the prices are coming down lately. It could be something else... this is just what my gut is telling me.

 

[2 4shofast]

Thanks I will try that and see what the outcome is.....I tried using doublesided tape and it didnt work. The chip is supposed to be completly vertical correct? Not leaning at the top or bottom?

 

[SHOWHAT9]

The installation of the chip is critical. You must clean off the pcm completely. If you didn't that could also be a source of your problems. Being in Italy, this is now like doing brain surgery over the phone. You also didn't mention ifyou are throwing codes through the SES light. The coils may be a problem. I'm not sure what you are referring to with double stick tape. When I installed mine, I used a piece of duct tape across the back of the chip from the bottom of the pcm to the top in a horseshoe configuration to insure no movement while it was re installed.

 

[2 4shofast]

After I removed the electrical grease I used rubbing alcohol and a q-tip to clean it. I used two sided foam tape to ensure that it was installed as flush as possible and would stick to the PCM and the chip. The very first time I installed the chip I did have the service engine soon light come on. After I reinstalled the chip for some odd reason, no I had now SES readings which still puzzle me. I even tried to use TEK which was recommened buy Superchip on the new PCM to no avail...so maybe the coils?

 

[americanmotorsport.com]

After I removed the electrical grease I used rubbing alcohol and a q-tip to clean it. I used two sided foam tape to ensure that it was installed as flush as possible and would stick to the PCM and the chip. The very first time I installed the chip I did have the service engine soon light come on. After I reinstalled the chip for some odd reason, no I had now SES readings which still puzzle me. I even tried to use TEK which was recommened buy Superchip on the new PCM to no avail...so maybe the coils?

After you cleaned off the grease, did you use some Scothbrite on the connectors until you could just barely see copper on either side?

 

[2 4shofast]

I was told not to scrape it down to the copper but yes I did use a scotch brite pad that was provide. I scraped until you could see scuff marks on the connectors.

 

[americanmotorsport.com]

I'd go until you JUST begin to see copper evenly...this is hiow it must be done. Nwo if you go too far, then you're SOL.

Hopefully it is just a connection issue and not a programming issue. So the car is in Italy?

 

[2 4shofast]

Yea it gets a lot of attention over here you would be really suprised. Especally with the flowmasters installed it turn heads every where I go and of course I have to pop my hood when I get gas to "check my oil" LOL

I didnt bring the 93 over because of a 3.2L block issue with SHOShop not getting it done on time, its actually a good thing because the oil here is S*$@ and the gas is about $5.50 a gallon for anything over 90 octane.

But did I mention the Ferarri's and Lamborghini's EVERYWHERE? :burn_out: