Who's running the most compression...
 

On the street ???

If you have a sound / vid clip that'd be great

:metal: :metal: :metal:

Re: Who's running the most compression...
 

I'm running 22 : 1 in my '67 C-30...










































But it's a Diesel!:hm: ;)

Re: Who's running the most compression...
 

10.1 with iron heads and dist. 36deg. full advance you,ll have to run at least 93 oct. for sure as thats what my 383 is. it will valve rattle like crazy if you dont. 11.1 with alumin heads same thing. 9.1 is all around best for street i think.

Re: Who's running the most compression...
 

I've run as high as 10- 10.3 : 1 on a cast-iron headed SBC with a carburetor, but that's pushing it. I'm running a 12.2 : 1 CR 383 in my '82 Z28, but obviously, I'm running race fuel.

Re: Who's running the most compression...
 

8.5 to 1 on the maro, oh wait highest? i lose haha

Re: Who's running the most compression...
 

My current pulling engine is going into my 68' SWB project.....11:1 on 91 octane w/out problems........but I'm at 7000 feet elevation;) 840 rectangles, 800 Q-Jet, RPM air gap.

Re: Who's running the most compression...
 

Cool, anybody run'n propane (LP) ???

Re: Who's running the most compression...
 

Hey everyone I'm new to performace stuff. How do you measure comp ratio I have a comp. gauge that I got from a friend. :metal:

Re: Who's running the most compression...
 

Find your chamber size of your heads with your casting number......Go to Mor-Tec.......Then you must know what size/type pistion you're running.

example.....840 BBC iron heads have a 107cc combustion chamber + my L2349F TRW pistons spec sheet says that with 106.9 chambers I'll be around 11:1. If you don't know what piston you have, but the engine is stock, you can get an Idea of what piston was used from some GURU types around the net.

Re: Who's running the most compression...
 

That's what mine was when I had the 6.2 in my 72...


Chuck

Re: Who's running the most compression...
 

I'm running propane I think my motor has something like 10:1 compression, and it runs great I've been told that 13:1 is acceptable with propane without any issues

Re: Who's running the most compression...
 

18:1 in my 6.5TD.They actually can be made to run better by lowering from 22:1,sounds silly,right?
I`m picking up my fresh 327 today.It will be about 9.5 to 9.7:1 w/iron heads.I may get away with regular.It will be awhile before it sees service to find out.

Re: Who's running the most compression...
 

9.5 but im going to a vortec S trim over the winter, my lower end is basically stock ZZ3 but i have had a ton of head work,( port polish port matched to my intake three angle vavle job dual springs, 2,02 1.60 valves and ported and ploshed my intake lil bigger cam (roller) , and of course my erson (extremly loud ) gear drive ,< i think it steals ponies though.... lol but it sounds awsome.........oh i lose

Re: Who's running the most compression...
 

Not silly at all. You can turn the boost on up with the 18:1's w/o blowing head gaskets and melting holes in pistons!

Re: Who's running the most compression...
 

I have 14 to 1 pistons in my junk but I run race gas! I will run as low as 112octane without the spray but only 116 to 118 when its on the bottle!

Re: Who's running the most compression...
 

I run 9.8 on my alum headed 383, with 34 degrees of mechanical advance ,all in @ 2700 & 12 additional degrees in the advance can. Its fine on 91 octain fuel, but will ping a trace on 89 pulling a steep hill. :crazy: L

Re: Who's running the most compression...
 

I will be running about 11.5:1 on my iron ls1.

Re: Who's running the most compression...
 

8.9 cr in my MKIV block. a bit low for aluminum heads but im building a decent amount of cylinder pressure to make the best of my lower duration cam and flattop pistons.

Re: Who's running the most compression...
 

What system are you running ??? Holley Pro-Jection ???

Are you LP only or can you still run off gas when you need too ???

Re: Who's running the most compression...
 

my buddy had a 13 to 1 440 in a 70 duster but we had to mix av gas and super! It was one fast car for the street!

Re: Who's running the most compression...
 

I've got a 388 with 10.6-10.7, sportsman heads but it lives on 100 octane low lead avgas. It realy likes it.

Re: Who's running the most compression...
 

454 BBC LS7 12.25:1 crate engine with port and polished heads/matching intake and a 850 Holley. Premium and avegas 60/40 mix or premium and octane boost when the drum runs dry.

Kind of a crappy clip

http://www.youtube.com/watch?v=5ru1cCe62JQ

Re: Who's running the most compression...
 

You can run propane at 13 to or 14 to 1 no problem in fact it will help maximize power to fuel consumption raising compression, propane is 105 octane and loves high comp.

Re: Who's running the most compression...
 

10:1, no problems on pump gas at 12 degrees initial. I can bump up the timing some with some 104 race fuel in it.

Re: Who's running the most compression...
 

i had a det of 601 heads off a 305 and put them on my 355 race engine. ran 11:1 ran super unleaded and av fuel 50/50 around 32 degrees advance. dirt cirlce 6500 rpm. hottest would run was 230 degrees no problems. combustion chambers were 55cc and flat top 2 brow pistons.