[sleeps]

Whats the highest compression you have ran on the street?

I'm looking into buying a Shortblock from someone but says the pistons are 14:1, I know it depends on cc of the heads an headgasket thickness. But how much could I get the compression down you think? What are your experiences with high compression and street usage?


FYI, it's a 598" with pistons cut for c-460 heads.

 

[jon volk]

What fuel are you willing to pay for on the street?

 

[EB85]

There was a guy years ago in Hot Rod (why am I thinking Mike Moran?) who had a super beater of a Nova that was something like 13:1 and he ran it on 93. He had all kinds of tricks to do it, though. Tiny, little converter with a huge stall speed, overkill cooling, light foot, all that stuff but he did. Granted, he mixed in the good stuff when he raced but it drove with 93 on the street.

 

[hotrodt]

What fuel are you willing to pay for on the street?

Yep, it's not the compression that'll get ya, it's the money your going to spend on fuel, buy the shortblock, put large chamber heads on it with thick head gaskets, tune it for E-85 and have fun

 

[pro801]

I had a '66 chevelle with a 302, 13.1 C.R., ran on sunoco 98

 

[8liter]

Could pull it off with E85.....maybe.

 

[backNblack]

13.5 to 1, turbo blue

 

[AFTERMATH]

I ran my 415ci 13.5:1 on the street all the time but I would mix 93 with 116 just to be safe.

 

[fatkid]

I run vp n02 its like 121octane on the tsreet. Guess its up to you how much you want to spend. A bunch of guys run race gas here on the street.

 

[crfbenny]

almost 15 .1 sbf on street, but c-16 aint cheap , depends on what u can afford and how much u actually drive it and call it a street car and it being truly a street conversation race piece

 

[slowmaro]

My motor is 11:1 SCR and I've run 89 octane without issue. Might try 87 just for shits and giggles.

 

[DaltonGangRacing]

Blown
head gasket Im guessing!!!

 

[backNblack]

only took mine out on the weekends but had a blast

 

[slowmaro]

In theory with the right cam you could run 14:1 SCR on pump gas... It wouldn't be optimal performance wise but it can be done.

 

[rat infested]

It depends on wether you want to stand on it or not and what cam shaft you run. You can easily run 13-1 with an aluminum head and nitrous cam. If you are good with your timing curve you can stand on it after some testing. I know a pile of guys running 1st and 2nd design GM flat tappet cams at 12.5-1 in 302-406 ci. iron headed small blocks running mid 11's-13.00s ET's in street cars on premium pump gas. You can easily add 1/2 to 1 point compression with aluminum heads.

 

[427Capri]

I run a 582 Chevy on the street but it has 10.5 compression. I chose not to go with the higher compression after watching my neighbor leave his 13 to 1 compression 565" Chevy II street car sit for over a year because of what it cost to feed it race fuel. I've driven the shit outta mine this year, been a lot of fun

 

[jeff c]

13.8 to 1 on e85 all the time. 2.98 a gal also right know. ran avgas in it before that 4.95 a gal

 

[slowmaro]

It depends on wether you want to stand on it or not and what cam shaft you run. You can easily run 13-1 with an aluminum head and nitrous cam. If you are good with your timing curve you can stand on it after some testing. I know a pile of guys running 1st and 2nd design GM flat tappet cams at 12.5-1 in 302-406 ci. iron headed small blocks running mid 11's-13.00s ET's in street cars on premium pump gas. You can easily add 1/2 to 1 point compression with aluminum heads.

It has never been proven that aluminum heads make a difference in what octane you can run. It's just one of those things that sounds logical so everyone repeats it as fact... But it's not.

 

[slowmaro]

http://www.empirenet.com/pkelley2/DynamicCR.html

 

[fasteach]

13:1 BOSS302...for me it's all about valve events.
Mechanical compression is one thing, and dynamic compression is another.

Damn...tree'd by slowmaro.