my car is soon to be 12.8:1 to 13.1:1 and a couple of my buddies said i'd have to run race gas but i was wondering what would happen if i jus filled up with 93 octane premium gas will it jus peak like a turbo with fuel cutoff?

 

i would say your are going to detonate pretty badly and are high risk to loosing your motor..
no way in hell i would try to run it in my car.

 

Why so high of compression? There have been many high HP NA builds done with much less compression than that.

 

That compression is ridiculosly high, especially for a street car.

IMO you would be making more power with 11.5-12-1 compression on any setup using 93 octane.

You are going to have to pull timing to get it to not detonate on pump gas, thus reducing power output. With lower compression you would have more room to tune power out of it instead of playing on the verge of detonation the whole time.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by WarpedSportzKid &raquo;</TD></TR><TR><TD CLASS="quote">my car is soon to be 12.8:1 to 13.1:1 and a couple of my buddies said i'd have to run race gas but i was wondering what would happen if i jus filled up with 93 octane premium gas will it jus peak like a turbo with fuel cutoff?</TD></TR></TABLE>

You'l be fine on pump gas assuming the tuning is done correctly. We have 5 shop cars that run 12.5+ on 93 reformulated pump gas - no problems.

If you need assistance with the tuning give us a ring, we're just up the road from you in Milwaukee.

My personal car is 13.0:1 and it's never seen anything but pump gas.

Clayton @ King

 

Also - what camshafts are you running?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Ausmith &raquo;</TD></TR><TR><TD CLASS="quote">Also - what camshafts are you running?</TD></TR></TABLE>

x2

Your cam profile will have a huge impact on what your dynamic compression will be. If you plan on running ITR cams with 13:1, good luck...I was limited to 18-19deg WOT spark w/12:1...however with the BC5's and Pro2's I've ran since, I was able to tune the most power out of the spark before running into predet.

There are plenty of 13-13.5:1 B-series runing on pumpgas. In fact, that compression range is ideal for most of the large camshafts out now. Look at the BC5's, Pro2's, Pro3's...you should be fine with ignition spark advance.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Ausmith &raquo;</TD></TR><TR><TD CLASS="quote">

You'l be fine on pump gas assuming the tuning is done correctly. We have 5 shop cars that run 12.5+ on 93 reformulated pump gas - no problems.

If you need assistance with the tuning give us a ring, we're just up the road from you in Milwaukee.

My personal car is 13.0:1 and it's never seen anything but pump gas.

Clayton @ King</TD></TR></TABLE>

This is why I'm tuning with King after my build.

 

you can run it with pump gas, I'm running 13.1:1 on pump gas (94)

its no fun on the street though, my car pings at wot anything lower than 5k on pump, on Race gas it drives like a beast

I say you lower your compression to something managable ~11.8-12.5