• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

should i top swap?

hockey101

hockey101

New member
Hey, new to the forum and i was wondering if i should top swap my 97 Grand Prix GT. I have been researching the option of doing a top swap for a while but i'm not sure if it's worth my time, seeing as the car has 150k on original engine and trans. So i'm wondering if i should do it and if i do what i would have to do to the bottom end and the trans to keep the car running reliably.
 


if i were to get a 4t65e or 4t65e-HD trans and i went ahead with a top swap how would the bottom end bear seeing as it has 150k on it?
 
I think you also need to consider adding headers with your top swap. It will knock a lot with the stock exhaust.
 
does anyone know if i grab a 4t65e trans is it as simple as just putting it or will i need other things to go with it?
 


someone correct me if im wrong but i believe there are a couple of adapters for some sensors that need to be purchased
 
1 u just need the gtp map pigtail

edit: just for engine didnt see trans questions
 
So which do you guys think would be better (or cheaper)?

Replacing trans and going with a top swap or replacing the trans and dropping in a GTP engine?

By the way i think my a/c compressor is just about shot and if i top swap i may as well replace that too.
 
Yank your transmission out...spray it with brake clean and sell it off to someone on CL would be my best guess...keep your bottom end if its in good running order...toss a cam or rockers in it if its out of the car...would make life really easy there...also, yes on the headers...I wouldn't NOT run headers with a motor utilizing higher compression and boost. Start with a 3.8" factory sized S/C pulley and work your way down from there...but most of the time a top swapped, header'd car will run great with just a stock pulley...in fact a stock pullied TS'd car will run what a 3.4" setup GTP would be running...about low 14's/high 13's if the tune is good and driver mod is there. When you source a transmission...if funds allow it...get a good condition N/A transmission from 98-02...since it has the same 3.29 gearing as your current trans does...then if you care to...swap the differential from a GTP transmission...not required, just something nice to have since it is stronger.
 


would the trans just drop in or do i need anything else to make it work?

if i buy a top swap kit from ed containing:
heads
valve covers
lower intake manifold
injectors
fuel rail
supercharger
TB (no maf)
vac lines
idler pullies
brackets
balancer
what else do i need and about how much will gaskets run me?
 
Last edited:
couple of hundred in material (gaskets and rtv)

you basically need all the top end gaskets of the motor
 
Youll need belts obviously, and you need an L67 map sensor, with the extension probably. Id suggest the top swap hardware kit from WBody store, it looks like it has more parts than zzp for the same price.

But in reality, sell your car and buy a GTP. a LOT less hassle and cheaper.
 
The only thing I have against buying a different GP is mine was bought new by my dad in 97 and it was always garage kept and maintained.

My GP got all new struts and springs last year and all of the common problems have been fixed/replaced.

So buying a new GP would be kinda stupid in my opinion because i know for a fact that mine is currently problem free and i wouldn't even be able to sell mine for what its worth and buying someone elses i would probably have to replace everything i already fixed on mine, so it would cost me more money.
 


So i think i'm just gonna swap the whole engine, along with the trans.
If i want to get a smaller pulley in the future what else should i do while i have the engine out of the car?
oh and what kind of headers and downpipe should i get?
 
You must log in or register to reply here.
Back
Top