Ecm change

I got a 95 caprice wagon lt1 obviously it's obd1 im new to modifying newer cars. There's a speed limiter on it and im wondering if the old ecm can be reprogrammed or should i get a stage 2 replacement chip i found on summit? Any other suggestions?

visit impalassforum.com

read the stickies in the tech subsections.  You will find your answers there.

don't get a chip from summit. Either get a mail order tune or the scanning/tuning software. The latter is more time consuming and has a learning curve.

If i download software like that I'm assuming ill need a tuner then? Those are as much and often more expensive than the chips that's why i thought about it. So im assuming then the original can be reprogrammed? Ill check out the other forum and see what they say thanks

the software is free ($EE hack). The cable is very cheap, 25-50$ tops.

The pcm can be reprogrammed. You can mail it out to the tuner or get the tune via email if you have the cable to load it. Usually cheaper to buy the cable vs the cost of shipping.

a few tuners:
pcmperformance.com (Alex Rutenberg)
lt1pcmtuning.com (Solomon K)
PCMforless.com (can't remember the guy doing the tunes, but it's not the original guy. Have been dissatisfied with him in the past and so have others recently).
Ed Wright

Ok awesome. The cable must be a USB to obd1 then? Where do i find one of those?

my cables are serial to ALDL, they end with a single pin, goes in the lower right hole in the OBD1 connector. I use a USB to serial adapter. I'm sure they make USB-OBD1 cables.

Type in the 1st address from my previous post in your web browser. Then click on "cables & harnesses."

Thanks I appreciate it. I went to Solomon k website and im definitely going with him and im doing it via email once i get the cables i need. Thanks again for all the information i really appreciate it

I used Solomon for my last tune.  It was pretty good.  He offers 2-3 free tweaks to the tune, which is nice. Ends up being worth it if you make some changes down the line such as gear ratio change, tire diameter change, EGR delete, etc

Pretty reasonable prices as well. Good turn around times. Seems like the best deal

I've used Solomon K. for tuning on my current 1996 Caprice, and have been very satisfied with the result.

Most of what I've read testimonial wise he's pretty highly recommended. I've got a few things to do like air pump delete and a ram or cold air intake before I get him involved i think.

If you want to be cheap, just cut the bottom out of the stock airbox (i.e. make the oblong air hole into an L shaped hole by removing all the material on the front and outboard vertial part of the box, below the filter level). Find a used drop in k&n filter for a bit of added airflow. On a stock cam/heads engine it's probably enough.

I did that to a buick regal i had years ago it worked pretty well but im planning on at some point adding more power like headers possibly heads and a cam upgrade. Depends on the results i get from reprogramming it and what not. I might not do heads might just upgrade the rockers and springs and whatnot.

Also want to get a 52mm throttle body. Probably new injectors and upgraded ignition. Gotta start somewhere right?

A tune should be in your 1st mods. Just retune it if you do large mods afterwards.

Heads/cam requires a significant amount of research before doing it. A lot of people don't realize how much work goes into swapping a cam.

For the air intake, go with what makes you happy. The RAISS looks great, but I don't think it's worth the money on a stock-ish car. Neither is the K&N FIPK. I saw very little improvement going from the 'swiss cheese' intake to the raiss on a bolt-on car.
Upgraded ignition isn't really required. Won't hurt, but not optimal use of your money.
Injectors aren't required unless yours are leaking or you are at the heads/cam level
52mm TB. Debatable. There are gains to be had, but there are some crappy TBs out there. Also, you absolutely need to specify to your tuner that you have a 52mm TB, or you will do in your transmission. It's an easy swap though. If you want to squeeze every HP out of a bolt on car, go for it. Strictly bang-for-the buck, this should be one of your last mods.

Gotcha. Throttle body and ignition aren't all that high on my list. First is the air intake deleting the air pump and i really want to do headers.

That makes sense to do the tune along with the other first steps. Thanks for the info

best bang for the buck is rear gears and a converter,.the stock motor has plenty of torque,. but trying to move a 4600 lb car with 200mph gears, is not the best performance

Next in line might be upgraded shocks and a rear swaybar (first in my book). Power is nice, but not if the car wallows like a pig on corners or over bumps. Third might be brakes. If you go fast, you'll also need something that will slow 4600 lbs effectively. My 1949 Chevy truck had a spring steel bumper, but these wagons do not bounce well in collisions.

Lol yeah they do sway like pigs a bit don't they? I have put heavy duty gas shocks in the front and rear to stiffen it up a bit, i had looked for a rear sway bar but couldn't find one. I didn't really know where to look. Might be the first car I've wanted to hot rod a bit and had difficulty finding parts.

I did find front discs slotted and drilled ill be picking them up. I'd like to upgrade the drums to disc in the back. Have you guys had good luck doing that?

I was thinking gears maybe a converter a little down the line. I actually don't know the gears in the car now. The guy i bought the car from said it had been changed but he didn't know to what. He said it was limited slip but it's a one wheel wonder unless I'm going around a corner. What's your suggestion as far as a set of gears? I've never swapped them out before anyways wanted to get into it further though

phantom 309 wrote:

best bang for the buck is rear gears and a converter,.the stock motor has plenty of torque,. but trying to move a 4600 lb car with 200mph gears, is not the best performance

Sleeperwagon95 wrote:

I was thinking gears maybe a converter a little down the line. I actually don't know the gears in the car now. The guy i bought the car from said it had been changed but he didn't know to what. He said it was limited slip but it's a one wheel wonder unless I'm going around a corner. What's your suggestion as far as a set of gears? I've never swapped them out before anyways wanted to get into it further though

So true. Do NOT cheap out on the converter.

Only way to know without counting the teeth on the ring and pinion is to jack up the rear (both wheels) and spin the tire one full revolution. Count the number of turns the driveshaft does. It should also tell you if your limited slip is working (if both wheels turn). The stock Auburn diff is "ok." It seems to more-or-less lockup, but wheelhop and one wheel spinnouts will kill it in fairly short order. Most people go with either the detroit truetrac (highly recommended) -a worm gear differential that acts like an open diff unless it detects wheelspin- or an eaton 19559-1 (a more traditional clutch-type differential that drives both wheels but will allow "limited slip" in turns)

Figure out your gear ratio and let us know what it is. If you're lucky you might not even have to change them (I would say it's not worth the hassle if you have 3.23+ in there). My personal preference: no less than 3.42 on a true daily driven wagon. 3.73 if you don't regularly drive on the highway. Both my wagons have 3.73.

Ok so count the number of times the drive shaft spins with one full tie revolution? How do i get the gear ratio from that? I've heard counting the teeth but that's as far as i know. I'll do that and let you know how many revolutions it makes

If you have 2.92 gears, then 2.92 revolutions of the driveshaft will give you one revolution of both wheels (e.g while driving straight).  So if you have a posi, then turn the wheel one complete revolution and count the amount of turns your driveshaft gives you.  That number (X) is the ratio (X:1).

If you have an open diff then you'll need to either turn the wheel two complete revolutions (that's the ratio) or spin the wheel once and multiply the driveshaft revolutions by 2.  Same result, but the former is probably a little more accurate (easier to discriminate between 3.08 and 3.23 for example).

You'll want to use chalk to be accurate. If you wind up with a ratio that seems 1/2 of what it should be, you'll know why.

Stupid question: open diff does that mean one wheel wonder as in i turn one wheel one way and the other goes the opposite way?

Sleeperwagon95 wrote:

Stupid question: open diff does that mean one wheel wonder as in i turn one wheel one way and the other goes the opposite way?

yes,..

Thanks. Looks like Friday will finally be warm enough for me to work on it again