Supercharge to Non supercharged???

[brktracer]

I bought a 98 GTP a while back to save it from the Salvage yard, too nice of car. Anyway the Supercharged engine died decided I wanted to put a non-supercharged 3.8 in. I was going the route ofengine and trans together. Bought a wrecked 2000 Buick, Trans cracked. Bought aPark avenue, Trans no good.. Ok I give up, I now have TWO great running non supercharged 3800’s. Decided to put one of those in with the original GTP trans. I know Iwill have to drill the flex plate holes but where do I send the PCM off to be tuned for the Non Supercharged engine hooked to the Heavy Trans?? Thanks!!

[Slick2500]

Dude top swap.
Buy this kit from zzp ZZPerformance - Top Swap Gasket Kit #ZZ-TSGKT-38 it will be better than running a n/a engine in that car.
You just need the heads, lim, blower, tb, supercharger idler pulley the icm bracket and the harmonic balancer.

[atj8]

if money isnt an issue go with turbo...lol if it is top swap!

[txslow6]

So you have bought two extra cars to use for parts and neither worked for you? Congrats, you are up there for unluckiest guy on this forum. I would have been beyond pissed!


You could use any of the vendors, ZZP, overkill, w body store, intense racing, 3800 performance. Or just go to a junkyard and pick one up yourself.


Or if I were you I would just convert all your S/C parts over to the new engine. You already have everything.

[brktracer]

LOL At least the motors were good!! Actually I should say the Trans in the Park Avenue is good but it is a 95 Model which is pre electronic. Luckily I have very little in both cars and I will get most of what I paid at the scrap yard.. I thought about the Top Swap but I use this car back and forth to work.. Don't want to run Premium and want the fuel mileage of non supercharged. I know why did you buy the GTP? It was cheap and on a one way ticket to the scrap yard and I hate seeing a good Pontiac go to the scrap yard!! Besides this is a NICE GTP! I will try to post pictures if you want. Thanks for the answers on the PCM programing.. Going to try and stick with the Heavy trans.

[Travisgt2]

I would so top swap uhave everything you need to do it

[dbextreme]

I'd top swap unless you can find a L67 in your area, but sounds like you can't... Kinda like around here.. L36/L26's are everywhere.. lol

[dsmuts]

Bill boost is running a na motor in his gs. You'll just need a tune for the 2.93 gear ratio

[txslow6]

LOL At least the motors were good!! Actually I should say the Trans in the Park Avenue is good but it is a 95 Model which is pre electronic. Luckily I have very little in both cars and I will get most of what I paid at the scrap yard.. I thought about the Top Swap but I use this car back and forth to work.. Don't want to run Premium and want the fuel mileage of non supercharged. I know why did you buy the GTP? It was cheap and on a one way ticket to the scrap yard and I hate seeing a good Pontiac go to the scrap yard!! Besides this is a NICE GTP! I will try to post pictures if you want. Thanks for the answers on the PCM programing.. Going to try and stick with the Heavy trans.

No worries man! The cost of regular compared to premium is literally just a few bucks if you do the math. And yes post some pics cause we love them around here.

I would so top swap uhave everything you need to do it

We have an echo in here.

[REDCRAPGP]

Top swap it. You don't wont be payinf much more for premium vs unleaded if you do the math you won't be saving much.

[Slick2500]

And if you stay out of the boost the supercharged cars actually get better gas mileage than the na cars do, at least in my experience they did. My 01 GT in town was about 19 and 26 on the highway, my 97 and 01 GTPs both got 22-24 mpg in town and 30 on the highway. And as txslow stated its only a few extra bucks every time you fill up.

[brktracer]

Well I decided I have Two engines.. For now to get the car going I'm using the 2000 Lasabre Motor with 102,000 miles. The trans in the Lasabre was a 2:86 so hoping the PCM wont notice the diff between the 2:86 and the 2:93 currently in the GTP. The other motor I can do the Top swap and maybe some other mods down the road. Fingers crossed.. Tried to post some pictures cant get it now will try again later.. Thanks again to everyone for the advice!!!

[txslow6]

You will more the likely have to link pictures from photobucket or image shack.

[Z34Phoenix]

NA or SC what makes the mpg better or worse is the gearing in the trans.

[brktracer]

Its alive!! Took the time and transferred the MAP sensor and other sensors to the new motor so all the wiring hooks up the same.. Only thing not hooked up is boost sensor. Hit the key and we have ignition. Car idles perfect and runs great no codes, from stop to 60 all is great, shifts smooth, not bad power. BUT.... when you kick in passing gear about 3800 -4500 rpm seems to fall on its face not sure if its running out of fuel or something.. Changed fuel filter, had the GM dealer flash the PCM to a 3800 N/A still there.. Drivability is great as long as I don't have to pass anyone!! Any ideas??

[brktracer]

Damn Catalytic convertor!!! Noticed a dent in the one on the car and thought hmmm. Luckily I had another put it on problem solved. Noticed a little lopey idle and thought about a past post about using the supercharged injectors.. Changed them and runs even better!! Funny I can make a 67 Firebird run 9's in the 1/4 but had issues making my daily driver run,,Thanks for all the advice everyone!!!

[BillBoost37]

If you change injectors..you need to change tune.

[brktracer]

Bill, Do you think I should put the NA 3800 injectors back in?? It runs great the way it is.. Runs cool, cant make it detonate no surges or dead spots etc..

[dsmuts]

Probably because it's running rich

[BillBoost37]

If you water a lawn with a sprinkler..it's good right? Now water with a firehose. This is an example of what you are doing.

Look at the injector flow rates and you'll understand better.