pump gas or ?

[steel town]

Got this question .I've been running pump gas for a long time now in my 406 sbc it's just under 10.1 comp. it makes about 575 hp and I somtimes spray up to 275 threw it but mostly I run just motor . My question is do you think I can pick up any hp if I run race fuel when I'm running straight motor . I realize I'm pushing it with the spray but I only run the spray once in a blue moon .
I also wanted to know if I decided to give the engine a little more comp. say around 11.5 to 12.1 could I run this engine safely on pump gas with a mix of race fuel .it's a street car so I'd like to keep it mostly on pump gas without pulling alot of timing out .

[Maximum Race Engines]

What gas you run, or I should say, what gas the engine will want to run on, will depend on cylinder pressure. Static compression is not high enough to warrant race gas, but if the cam timing is too short, and cylinder pressure is way too high, it may like the higher octane leaded race fuel. Normally it will not want it or need it with that compression. Personally I wouldn't go 11.5-12.1 and try to run pump fuel through it, even by mixing, as I am not a fan of that at all, although you will get different comments on this. If you want to run straight pump fuel, stay 11.1 or under with the correct cam timing and aluminum heads you will have no problems. Going that half point higher will do nothing but lead you to detonation. If you want to run race gas, don't go under 13.5 as 11.5 or 12.1 won't make as much power, and will still need race gas.

[steel town]

Thanks Joe I was very adament about using 94 octane pump gas but I wanted more hp so I thought maybe I could raise the comp just a bit try my luck and mix it with race fuel . I then heard that you couldn't mix race fuel and pump gas and it made me rethink the hole idea .As you said if I did decide to go with race fuel I was going all or nothing and go to about 14-1 I just didn't want to run race fuel on the street could get expensive .

P.S. I run a dart iron head so I think I have to stay below 10.5-1

[Pooch565]

I used to run Iron heads on an 11 to 1 small block on 93 pump and it was fine. If want to run a "street" gas, try our Streetblaze 103. It is oxygenated and unleaded. It will make more power and will go up to 13 to 1 compression with no problem. We have guys mix pump with race fuel all the time. I have never seen any bad come of it. You could even mix 103 with pump and be fine. Good luck.

Jason

[Nosman]

Hey Brian, just for a little comparison, my old 406 was 10.8 to 1, Sportsman head, and 264/266 shaft in it, and as soon as put 150 or so in the plate, thats where I started to notice the little hint of detonation. I think yours makes a little more steam than mine did, but I'd probably take Pooch's advice and mix a little of the good stuff. Have fun with it, those 400's are so much fun!

[steel town]

Hey Buddy long time no see .I broke the 406 she finaly told those parts to get out and walk .it was a good engine and I can't complain how many people can say they've had there engines as long as that old girls been around . I went out and got a bowtie block and I wanted to order a scat rotating I want to be able to hit it hard if needed and not worry about it ,not that I ever worried about the old block .

[Maximum Race Engines]

11.0-1 with iron heads and weasel piss for fuel? Ouch..were you idleing around town with less timing? ;) As for mixing, never a big fan, two completely different types of fuels. Not something I promote but I guess that's a preference.

Pooch-
Phone tag is fun, and your it by the way..:rolleyes:

[9SecBuick]

hey Joe check your pm's please,

Thanks
Doug Keen

[Maximum Race Engines]

Checked and replied Doug.

[Pooch565]

Joe,
I'll call you tomorrow at work. And then you'll be it.

Jason