Performance Chip Question
 

I about to pull the trigger on a 911 Performance Chip (Steve Wong) and I have the following question/ concern:

I have a 1987 911 and my intake manifold is hand ported and polished does having this mod necessitate have a chip custom programmed? Or could I still go with one of the standard offering's?

I am trying to get a feel for if this mod is significant enough to impact things or not.

I also have a Euro Premuffler and B&B muffler/exhaust + stock headers.

Appreciate the feed back guys!

Merry Christmas too!!

First you should dyno your car as it currently is to know your base line. Then talk to Steve W about what you've got (mods) and where you want to go. Dyno the car afterwards to verify what you have. Otherwise you'll be paying for what you 'think' is an improvement and sometimes it isn't exactly what you think.
It is possible the chip will need to be redone to get the result you started looking for. Steve does great stuff but you still need to dyno the car before and after to be sure.

My first performance chip install (not SW) actually dropped 10hp from stock! All it gave me was a higher redline. Not necessarily good when max torque stayed at 5800 rpm's.

First thing, call Steve. I too am about to pull the trigger on a SW chip. I had some questions so I got the phone number off of his website and called and left a VM. He called me back quickly and was VERY helpful and patient with me. I bet he can answer 99% of your questions you may have.

Anyone know about how much a Dyno run costs to have done and perhaps could recommend someone in the San Diego, CA (Carlsbad) area?

thanks!

If you go for a dyno by yourself, it's could be several hundred $. If you get a group together to meet at a shop on a Saturday morning or something, it would be a lot less money.

I'd be up for participating.

The real answer lies in how much does the ported and polished intake increase airflow. There's a good chance that one of the mods, the intake or the chip will cancel each other out, and who knows what kind of AFRs you're running right now.

You've pretty much bought yourself into a trip to the dyno before the chip, so you might as well do the whole thing.

About half a dozen NC pelicans did the same several years ago for a minimal cost. FWIW, I did six back-to-back runs swapping out the stock chip and SW chip between each run to compare the results. Everyone there (that day) concluded that there was no discernable difference between the HP and torque curves between any of the runs (performed on a Mustang dynamometer - VERY consistent btw), but YMMV. I realize that some show improvements on a dyno, but I didn't. Caveat, I really like my SW chip, but from my perspective, the benefits are mostly derived in his partial throttle mappings, and simply weren't quantifiable in 4th gear WOT (wide open throttle) dyno runs from 40-110 mph. My car did compare VERY favorably with a 3.6, and some early "hot rods", including a 3.5 twin plugged MFI. I take dyno runs with a big 'ole grain of salt, but both the stock and SW chip produced VERY nice consistent hp & torque curves. It was a lot of fun, and a learning experince for me :).

Dyno run
 

I called a shop in Tampa last week and they charge $150 for a 1 hour dyno run.

Recently attended a dyno day and my 3.2 '84 with a sw chip, bb muffler, test pipe, and a kn filter made 20 hp over a ROW 3.2 and as much as 30 hp more than other 3.2s and 3.0s. I wouldn't have believed that there would be that much difference but there was.

As noted above, I would call SW. He knows these cars and probable already has a base chip for your car.

I would not dyno or do may WOT runs until you get his chip. If you do dyno, have the operator watch your Air Fuel ratios and be ready to abort if you start going lean.

With the stock AFM there is not really any air flow compensation after 5-5200rpm. If you have opened up the exhaust and the intake, you may be flowing more air than expected. The motor may compensate reasonably well up to 5k but after you may be lean and at risk.

When you do dyno. Disconnect and unplug the O2. Have them put there wide band O2 in the stock O2 location. Make sure the dyno operator knows you are going to use his info to reset the chip. He may want to recalibrate his system.

With the custom chip option, after you have your AF's he will email a new chip and you then return the first chip.

I think the custom chip option is the only way to go. Not all cars are adjusted exactly the same and may have varied from spec over the years. The only way to be sure is to dyno.

If you are in the market for a performance chip, then SW is the only way to go. He has spent more time with me via phone calls and e-mail then my own docter. Recently I discovered my 87 Targa was rebuilt with euro pistons and cylinders. SW advised me this would make a big difference in the chip I had orig. purchased. My chip is now on its way back to be re-programmed. Thats service.

A few thoughts on this subject,....... :)

1) I think the world of Dr. Wong's products. His software WORKS and delivers what it promises. I cannot say that about very many things out there so I strongly recommend it.

2) Its important to remember that you don't drive a dyno,...:) While these devices are very useful (we have both an engine dyno & a chassis dyno), they cannot measure throttle transitions or throttle response and thats a large portion of the gains provided by properly made software. Drivability is just as important as raw torque/HP numbers and thats something that Dr. Wong's chips do very well with.

3) Every engine is a little different (even with the same specs) and software must match any changes or modifications to see the maximum benefits from such changes.

JMHO so YMMV, :)