I have a 92 camaro Z28 with a 350 TPI. Its all stock except for a brand new alternator. i dont know a lot about the computer chip or what ever its called but i was curious if theres a certain amount of high performance parts and upgrades you can have before changing the chip to a more powerful chip or however that works? Please help me out, thanks
kevin

 

Hey Kevin.

To Sort of Answer your question...

The PROM in your car reads info from various sensors, and then decides how much fuel to distribute, and how much spark advance to throw in. ( among Alot of other, less-essential things )

It is rougly calibrated to work with the stock engine, meaning that for an engine with a near stock vaccum level at idle, moving a similar to stock amount of air at a similar to stock RPM range, it will work fine ( if you consider stock operation fine )

Once you start doing things like, heads, Cam, exhuast and intake mods, your going to start moving alot more Air.

As a result, The calibration of the stock PROM is going to stray more and more from ideal... eventually to the point where the flexibility of the computer to tune itself wont be enough, and the car wont run right. Espeically with Low-idle Vaccum Cam's.

So, If you are a typical thirdgenner and love putting things like MSD ignitions, TB Bypasses, and TPIS Airfoils On your car and bragging about them, Then you might as well leave the chip alone.

But if like some of us, You enjoy the actual rush of acceleration in the Sub 14 second catagoy, You may want to waltz your way over to the DIY- PROM board, and learn everything you ever wanted to know, and more, about how to tune your stock PROM to fit whatever mods you end up doing.

 

Your sig implys that while "Us" enjoy sub 14's, you're still in the middle of them.

 

Lots of people brag about their TPIS Airfoils that's for sure! In fact just the other day I saw a sticker on someone's car that said TPIS Airfoil Equipped and the guy was running something like 14.55 and trying to covertly flame people who were asking legitimate questions, go figure...

 

I may not have gotten this car Into the 13's yet, But that dosent mean that Im content with a 14 second pig, either.

Being a fulltime Student Working 10.5 Hours a week, It takes a while.


Anyway, I said I enjoyed Sub 14' second cars, Not that I had One.

 

14's are fun either way

 

Both of my TPI cars have the MAF induction system and so the stock EPROM can support considerable air flow mods.

I believe your '92 has SD uses a MAP sensor to monitor air flow. This system usually requires mods to the EPROM earlier in the mods program.

There are seveal houses that do decent EPROMs and you can of course learn to program your own.

Generally if you do intake & exhaust, cooling and ignition mods you may get by tuning fuel flow with an AFPR. If you remove the valve covers consider a custom EPROM. You can use a scan tool to get an idea of when it's time to bring out the EPROM burner or the check book.

 

Yeah but give him some credit. He's running 98mph through 1 7/8" outlet LG4 exhaust manifolds w/ a 2" T-pipe (not fair to call it a Y)
I give him a B+ for effort. Besides, if you really wanted to rag on him you'd point out that he doesn't even have a fuel rail for his TPI set-up, much less taken the carb out yet

 

BTW, the correct answer to the question 'when do you need a chip?' is.....NOW.

Really. There are no hard and fast guidelines for at which point you really 'need' a new chip, but as bort pointed out, once your into the heads and cam you are most certainly wasting your money on go-fast parts by not buying the equipment to tune it. Why would someone spend several k on goodies, just to let it rot and run poorly. This isn't the TBI board where everybody's car runs 1 second slower than it should, on this board we like to get max return for our $$$, not brag about how our engine is different (yet strangley lacking in time slips)

But really, if you are an enthusiast, and plan on sticking with fuel injection for a while (might as well, it's not going anywhere), you might as well get into PROM burning as soon as possible. Stock is the ideal time to learn. Since your chip is already going to be really close anyway you can concentrate on all the little stuff in the chip and what it all does and means. You can justify the cost of the equipment just in the hassles and little costs it saves you.
For example you don't need to buy aftermarket fan switches since you can set the ECM to turn them on exactly when you want. You can also change a lot of personal driveability type things as well, like TCC lock-up points to make it more reponsive. Set the idle speed how you like it. Performance wise you can tweak the timing curve and find something that works for you. Just a few tries with this and you'll certainly out-do whatever off the shelf chip you can buy.
As for a laptop or scanner of some sort, if you want to be able to effectively diagnose problems with your car, a scanner can't be beat. And this can be done so cheaply that the first time something weird is happening with your car you have more than paid for it in money saved on professional dignostics. And thats not counting the POWER scanning the ECM gives you for tuning.

But if you just like to drive your car and throw parts at it every now and then, don't waste your time. Slap a chip in it after you've spent a few grand in it so you feel like you're doing the right thing.

 

LOL


Just wait Untill I get those headers ed, Your gonna be seeing One 13 Second 305 Im gonna guess, 101-102 Mph.

My Motor also has 180k Miles on it. The Rings have Seen better Days.