Thread: how safe is top swap

you can pull it off pretty easily, but if youre like me your car will be down once a month for something stupid.

ssm90 kit uses the stock heads, so if you're not mechanically inclined or don't have time or what not, you just replace the intake manifold and fuel rails IIRC, and a few other little things and run it off one belt. you'll need a tune from zzp, and a lot of guys say they have trouble running a stock 3.8" pulley without headers due to higher compression. if you top swap, you have to switch the L36 heads for L67 ones

I debated doing it when I owned my GT. I was actually planning to, until I found a GTP I liked, and bought that instead of top swapping the gt.

It's very safe. A member on clubgp named dbtk had a top swapped GT that made 385ish whp without nitrous (something like 445whp w/nitrous) and the engine didn't blow up until 264k miles. If you go the SSM90 way, be prepared to spend at least $1600 on the kit and start with their 4.2" pulley.

That SSM90 kit would be tits if you could run a Gen V and not have to buy $400 fuel rails.
As long as you have good supporting mods and a safe tune (no KR) you should be fine. Then enjoy having 5% more power than a GTP with better gearing.

Mines been SSm90'ed for 5 years with not one issue. Other then the STOCK gt trans is just now slipping.

Originally Posted by SDgrandprixGT

what supporting mods

When I first got the ssm90 I ran a 4.0 pulley with a plog and 3 inch downpipe. Ran that set up down to a 3.8 pulley for a year. Then got headers and went to a 3.6 and 3.5 pulley. Im now on a 3.25 pulley . below is how the car sits now


http://www.grandprixforums.net/green...-gt-42587.html