Is it possible to put GSR pistons in a 1990 LS engine without any problems? If so, how much compression would I gain and what would this equate to whp wise? I was wondering because I want to bump up the compression of my 9.1 motor into the 10 area (10-11) so I can get a few more ponies out of her without switching gas. Also, would this be a good setup with a LS head that will be shaved and port/polished in the future? If not, what would you all say would be a good setup without going VTec or boost or Nitrous and staying safe with 93 octane?

 

the small end of the rod needs to be shaved down on the sides. either that or u need to shave down the inside of the piston where the rod sits on the pin

 

How much will this up my compression and about what kind of gain for whp should I expect?

 

about 1 full point. gains will be very minimal. its the motor is still running strong i wouldnt waste your time and money with gsr pistons. go with itr or b16 pistons if any

 

and dont shave the head

 

So what pistons will I be able to go with...get no more then 11 compresion...and still be able to run 93 pump gas but still notice some gain? As long as I can still run 93 octane safely I will bump my compression up to whatever. Also, I want the least amount of modifications to do this (as in custom work to fit the pistons in).

 

rememeber with more compression you need to feed it also so with out a nicer cam to match the compression you will not feel to much of a gain but my money go with b16 pistons thay are cheaper

 

and as far as being safe on 93 octane, ima have to be that guy and say talk to MTBER cuz he will probably tell you anything less than 12 or so is streetable, provided its set up right.

 

Well I want to figure out what pistons to go with ahead of time because I want to get the head port and polish with new valves and guides and such plus the cams and cam gears before the bottom end goes in. The bottom end will probably be the last thing done. Is it fine to run the new cams and built head with stock pistons or would I need to do everything at one time? Also, on a side note, when you have an ecu programed can you reprogram it as many times as you want. I was going to get it done before all the head work was performed...then after and then one last time when everything was wrapped up since there will probably be a good amount of time between the head work and the bottom end being done.

 

if your going stock bottom with only pistons dont bother wasting your money on porting the head spend it on something that will help