I recently picked up a gsr block and head from a guy who was going to build it as a project, but was strapped for cash...

cylinder 3 seems like it had some damage from the rings (?), but I'm going to do a full rebuild anyways, so it's not a big deal..

I plan on boring and honing the block, and I wanted to put down about 250hp on 91 octane (all that is available around here) .. I know the gsr is capable of much more, but this is my DD for the next little bit, so I want something that is streetable...

The block came without a crank (why I'm not sure), so I was thinking of going with an LS crank and rods, and then low compression forged pistons...

all that being said, I know you guys on here are a lot more knowledgable than me, so if you could give me your input on what I need to achieve the 250hp reliably... This is going to be a slow build (I'm in university) and I want to take my time and do things right...

thanks!

edit: going in an eh2

 

The 250HP range that you are looking for can easily be accomplished with just about ANY STOCK B- series. Even the mighty D16 Sohc can do that, no problem. As for reliabiltiy, all it takes is proper installation and tuning.

 

With a completely rebuilt bottom end on 91 octane, you could easily make 350-400whp if not more depending on your setup. There's no reason to limit yourself to 250whp when much more is possible. For example, i made 315whp on my stock block GSR for 2 years on 91 octane.

 

what were you running for a setup at that point? stock block, and head?

what did you run for a turbo setup??

my main concern with 91 octane is to stay away from detonation... that's why I was wondering about what pistons to run.. I know the lower compression in this case, the better..

 

I was running a 100% bone stock GSR block from valve cover to oil pan. It had ~56,000 miles on it when i boosted it the first time...as of the start of my rebuild it had 74,000 on the clock.

The setup was an SLS Shorty with a GT3255b. The rest i put together myself. It was nothing very fancy, but worked well as a whole.

You're right for the compression; the lower your static compression, the more power you can make on 91 octane without detonation. The efficiency and IAT's come into play in your situation as well...which is why people run SC61's on the street and make 450+whp on pump gas; whereas, a 57 trim would NEVER make it there