IS this too high for street gas??

I'm thinking of boosting my CR to 12.4/5..

is that too high??

my other option is 11.7ish to 1

thanks for any input..

 

why are you thinking of boosting to 12+ for street use?

 

why not

 

well unless you're really building a race engine or some sort of crazy cam profile, why would you need/want to?

 

i have 10.2:1 now in my b17 (it was 11.1 in my b16)

i'm looking to up it to 11.7(itr) or 12.5(ctr)..

i have stage 2 cams..

 

o here we go again

 

If you've ever read up on something like the WD-40 shootout or other powerful street motors that were built by knowledgeable people, you'd notice one common thing with all of them that seems to get missed by the masses....actual comp ratio of 11-11.9:1. That range has consistently been shown to be the best range for street performance motors because of the available fuel at most gas stations and the ability to advance the timing when tuning for more power and reliability. Many people want 12:1+ but few ever seem to know why they want it.

 

what do you think of this kit

http://cgi.ebay.com/ebaymotors/ITR-P...mZ180345806393

 

I'm not sure about the rings in that kit but everything else sounds ok. Someone else that is familiar with those rings may be able to comment.

 

so far my motor

B17 block (stock)
B16 head (stage 2 cams, ti retainers and dual springs, light P&P job)
adj. cam gears
head milled .030"
ANR headers
Skunk2 intake w/hondata gasket
70mm bbk TB
3" ram air, with duct down to pick up cold air (less water problems and filter stays dry)
450cc injectors
hi flow cat 2.5 custom exhaust
unsprun ceramic clutch, 9/10 lb flywheel
quaife diff and custom geared tranny


i've changed from a b16 block to b17 block and lost about 1 pt of CR...

my question is 12.5 is too much?? is 11.7:1 the better bet?

 

You obviously haven't read in this forum at all. If you had, you'd know that 12:1 is on the ragged edge of what pump gas (93 octane) will support.

If you want to live more dangerously than that, have fun!

 

12.5:1 is doable on the street, with big enough cams and a good tune.

 

What does the person whos going to tune your setup think?

Or is it basemap por vida

 

Yes

 

heh, never had any problems with 12.5:1 on pump.. Just need good cams and header.

Acutally now that i think about it, I had one customer that I did that had a GSr with CTR pistons, S2 Pro2 cams and a 75 shot direct port on pump.. In a CRX lol .. car hauled ***..

 

Why are you asking, and why are people responding to a "boosted" application in a NATURALLY ASPERATED forum? OP - go to the Forced Induction forum, you will yield better results THERE. Good luck.

 

He's not "boosting" as in turbocharging. He's boosting as in upping his CR.

This thread is retarded.

 

Oh **** I'm sorry...I'm a little drunk - kinda miss read the nonsense

 

yeah my ls vtec had USDM type Rs in it that is about 11.0:1 compression and i made more horse power then guys with like P30 pistons so i mean it is not all about compression ratio to make more power

 

Hey, at least you would be able to accurately calculate your compression. I bought a ported head on here and the guy said it was slightly milled, just for me to find out after the fact, that it was aggressively milled for a stock bottom end B20 in the Honda Challenge. Where my compression was estimated to be 12.4:1, it is now estimated at 13.5:1, on sub 92 octane pump gas daily driver . Had to pull timing like a bitch.