mypontiac

Is the GM performance prom for the 91' 305 the same as the SLP prom for the 91' 305 ?

I know that GM was selling SLP products as part of there performance line in 91', but were the prom chips the same??

mypontiac

Isn't anyone familiar with this????????

Rob P

iTrader: (1)

You probably want to post this on the prom board. Though you will have to put up with mulitple disertations about buring your own proms etc LOL!

Grim Reaper

Didn't like my answer on the DIY Prom Board?

Just to re-iterate NONE of those "off-the-shelf" eproms do much of anything. A couple extra degrees of spark advance (which usually triggers the Knock Sensor to pull out more than was added), a bit more fuel (which is generally the last thing a bascially stock engine needs as the stock eprom is far too rich due to GM Warranty concerns), and locks the TCC (if an automatic) a couple MPHs higher (debateable mod).

Nothing else. For that amount of money, you'd be far better off with the equipment (it would be not much more money) and then you could a LOT more...like properly controlling the Knock Sensor to get the MAXIMUM spark advance your engine can handle without detonating, the PROPER fuel mixture so it isn't too lean but not too rich, alter the TCC locking speed to what YOU LIKE, adjust the fans for a different temp T-Stat...just to name a FEW of the things you can do.

Go to www.tunercat.com and look at the various ECMS they handle and if you find the RIGHT TDF for your car, you can see all the things you can change. It's a heck of a lot more than you can imagine.

If you are NOT going to burn your own eproms, stay with the stock prom. Even "custom eproms" are not that much better unless you can find an "engine tuner" that will have "hands on access" to your car. This "eproms by mail-in specs" don't really cut it either.

Brian K

Then explain the HP gains horsepower TV got on the thrid gen 305 firebird. 13HP with a hypertech chip, and 160 thermo.

mypontiac

Thanks for the info Glenn91L98GTA.

It is just that I am doing a full SLP set up on my 91 TA similar to list member 92GTA. This was a set up that was offered by GM through SLP back in 91' and 92'. This package included intake and exhaust modifications and also a performance chip. I recently found two specific proms for my car. One was a "SLP" prom and the other was a "GM Performance" prom. The GM performance prom was programed by SLP and sold through GM as part of the package. I wanted to see if the SLP prom was the same because it was being sold at a better price.

I actually need the added richness to compensate for the induction and exhaust SLP mods which I will be doing.

So in this case I don't mind the programming of this premade chip since it will go with the other components.

Actually a rep from SLP contacted me and told me that the proms were the same.

I may still look into the programming if I do any internal modifications which might require it.

Thanks.

Grim Reaper

First, please give some details. I don't watch those clowns (that's how much I value their opinions).

But, I've ran "binary" compares between the Hypertech (plus every other "off-the-shelf" eprom) and the "stock" eprom (and there are a variety for specific cars, even with the same engine/tranny/year combo). Bottom line, there is VERY LITTLE in them and if you got 13 HP, you'd be lucky. Often, on an old engine, the "little extra" spark they give often triggers "knock retard" which makes you slower. But there is a LOT more to those "tests" than meets the eye.

Hell, according to TV you can run your engine across the US with no oil.

Give me a break.

But, I can tell you this. That "whopping" 13 HP amounts to 1/10th of a second (if that). Just practicing your "launches" will accomplish more. But, by properly "tuning" your eprom, I've shaved 1/2 second off my times. At a cost not much more than that "Hyperjunk" AND I now get almost US 30 MPGs (by invoking Highway Mode and proper spark advance) which paid for all my eprom burning equipment in under a year.

.1 - .2 of a second is not enough gain to overcome "differences in launch techniques" to convince me there was an actual power gain. Get .5 seconds, and I'll listen.