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The BUCKY
12-08-2008, 07:08 PM
if i use 11.0:1 compression pistons in my gsr will it be safe to boost it later on? cp pistons is the plan

E=MC˛
12-08-2008, 08:31 PM
i know some people boost type r's but i think they only run like 5 psi stock. just depends on how much boost you want later.

bRiAnMcIvIcS
12-08-2008, 09:23 PM
You wouldnt be able to run very much boost. I would do 9.8:1.
Are you serious??? That C/R is really high for boost.

The BUCKY
12-08-2008, 09:41 PM
dead serious. rebuilding the motor. has low compression pistons now. wanting to try higher compression so when not in boost its not terrible

The BUCKY
12-08-2008, 09:45 PM
what the stock compression for a gsr?? 10.0:1?

green91
12-08-2008, 09:58 PM
11.0:1 is possible with boost but its gotta be a VERY good tune, not much margin for error or you're in detonation territory. I really like my c/rs to be in the 9.5:1 range for decent out of boost throttle response but also good boost response.

bRiAnMcIvIcS
12-08-2008, 10:10 PM
10.0:1 could be ok if you dont go boost crazy. I would use cp pistons or wiseco pistons and eagle or scat rods. Anything under 9.5:1 will be really sluggish out of boost.

Whats your power goal?

The BUCKY
12-08-2008, 11:03 PM
350-400 on high boost. i do want to take it to the drag strip once in a blue moon

BTEC
12-08-2008, 11:21 PM
the max id go is 10:1
u still get good driveability and forged internals will allow u to run a descent amount of boost but yeah, ur gonna need a good tune and descent size turbo so u dnt max out its efficency and start blowing hot air which will increase ur chance of detonating. lol!!!

i just felt like talking. shitll buff out but if u sked so mutha-dammit!!

i tried to get 10:1 je's back when i built my first engine and race engineering refused to sell them to me bc i tol dhim i was gonna boost the engine.

cp's suck!! id get JE's. Not SRP, but JE. Theres a difference in the metals. R&D is what i love. Good luck

The BUCKY
12-09-2008, 12:14 AM
what is stock compression on a GSR? i wont be boosting for a lil min. gonna take my time and put together a good setup. already have love fab topmount and 4" dp

Vteckidd
12-09-2008, 12:20 AM
11:1 an 10psi is a badass street car with a small turbo

Cylinder pressure and temps is your main problem.

id run the 11:1 pistons with a thicker headgasket to get it around 10.5:1-10.7:1

The BUCKY
12-09-2008, 12:28 AM
i thought thicker headgaskets were a no no. if i run 10.0.:1 or around that. how would if feel compared to a stock motor until i boost it?

EmminoDaGreat
12-09-2008, 12:49 AM
It will run like a 10:1 motor all motor. = slow.

T34me
12-09-2008, 01:02 AM
im doing same thing man, running pr4 rods with GSR pistons in a b18b block for a 10:1 ratio, which is stock for GSR and putting 6psi to it from a JRSC. People boost stock GSR's all the time, so its not too high of a compression to work with, trick is what you already know, the tune. Scotty at mainstream FTW

patrick4588
12-10-2008, 03:19 PM
i was running 9.8:1 cp pistons and the head was milled twice so i would say the compression ratio was over 10:1 and i was running 17psi on 93 octane without detonation issues. i think if you were to use 11:1, just run a simple low boost setup on 93 octane and when you wanted to go to the strip get some 116 octane and turn the boost up.

BTEC
12-10-2008, 03:29 PM
i thought thicker headgaskets were a no no. if i run 10.0.:1 or around that. how would if feel compared to a stock motor until i boost it?
I had an hks 3 mil headgasket on my stock b16, arp studs and 15psi. i had no problems out of it. well until the oil pump came apart.

xdavidscenex
12-10-2008, 03:38 PM
id go 10:1 max on boost. it would be fine NA lol prolly feel like a stock gsr.