Can you run 10:1 on your DD with pump 93?

 

Yes...but why? You'll have to be much more careful with boost and timing while tuning. For pump gas setups stick with 9:1.

 

I was just wondering. From my research it shows you could go either way, or it comes down to your tuner.

 

That is true; it just narrows your margin for error.

 

True - what if you run 10:1 and run your E85 map as aggressive as possible.

your 93 map you would dial back for you DD ?

 

I was thinking of the same when I eventually build my motor. 10:1 CR, run E85 daily, and have a safe 93 map for when I need to go on long road trips

 

I run 10.1 on 93 as do plenty of others you can make more then enough power with it. whats your hp goals and turbo setup ? 10.1 in this day and age does not really limit you much there are guys running around on 30 psi on pump i have a hta86 stock head built bottom end ect and i make 580 dyno jet on 28lbs on 93oct.

 

Any thing is possible. Try it out.

 

I also run 10:1 with a 3586 at 28 psi on 93 octane. No issues at all and it pull like a freight train! And it really goes nuts on E85 at 38psi

No issues at all, a GOOD tuner and you will not have an issue at all.
When I was first doing my build plenty of tuners thought i was nuts to want 10:1 cr motor with over 25 psi of boost, most shops said no more than 22 psi!!! Its simply sad how many terrible tuners and shops are out there... Just glad I picked one of the best

 

It all works you just can't be aggressive on 10:1 on non race fuels. Some claim or do make power on 91/93 oct with such compression but there are greater risks with error. Heck im going 10.5:1 but i'll be on e85 99% of the time. If I ever had to pump California 91 oct in I would only plan to cruise...

 

I have run my 10:1 compression motor on 93 before, I wouldn't do it on a regular basis. Stick to 9 or 9.5:1 for pump gas.

 

This thread makes me laugh.... its completely fine and is all based on the tuner and his/her skills! If your tuner isnt able to tune higher compression engines at higher boost and you dont want to find someone that is capable of doing it properly then stick with a lower cr engine...

But how I see it is, if a tuner cant tune a higher cr engine at higher boost (30psi on pump) safely then I dont think I would want them to tune a lower cr engine either... Just saying...

 

You've obviously been brain washed by your tuner.

 

Indeed.

No amount of tuning can stop high cylinder pressure and heat in there when trying to run that much boost on pump gas on higher compression.

 

Consider that MIVEC changes the dynamic compression ratio when you adjust both intake & exhaust cam timing.... It's all about the tune.

So at any time you could sacrifice the ideal cam timing and lower the pressure in the cylinders.... In transient situations where the pressure might spike, run less intake advance and less exhaust retard to artificially lower the dynamic compression. (waiting longer to let air in, and releasing it sooner essentially)

You can also drop boost, refuse to hold boost high as long, adjust ignition timing, or refuse to build boost in the lower RPM etc.....

MIVEC is the key if you ask me.... Even if it robs power to not run ideal MIVEC settings, you can bet it's safer on the motor with a smaller dynamic compression ratio.