Blown SBC limits ?

Hi guys, I've only been in here for a week or so and glad I found this site! I'm pondering the idea of putting together a TAFC team for next year but that's a subject for another day. I apologize for the non-alkyhaulic car question but if anyone will know it seems to be you guys. Now, I have a 3% under Weiand 8-71 blown 406 on gas using 2-750 BG carbs currently showing 14-16 psi boost in a '64 Chevelle that I'm going to switch over to alky. I've just installed the new MLS head gaskets and have AFRs' 220 heads at 9.1-1. I built it a true blower motor so it should take anything it can built to. My question is this. Whats everyone thoughts on how high can I drive this blower and still keep it together?
I'm not afraid to push it til it breaks then back off some, just would like to have a good idea of what someone else is pushing them to out there. I've read other SBC posts that someone was even using a 14-71 on an SBC! This kind of info face to face is hard to come by. Thanks. Rick questions?

 

Blown SBC

Hi Rick,
I am running a Blown SBC in T/D for a year and a half now. I am sneaking up on it, so far the only problem I have had is head gaskets leaking between the center cylinders, I have talked to many people including the Santo's brothers and it appears to be the weak point becouse of the exhaust valve placement. I have machined inserts for the center cylinders and so far (knock on wood) they seem to have cured the problem or at least delayed it (I was down to 10-12 runs before haveing to remove and service the heads). I left the engine in the frame rails all last year freshened it over the winter (block had cracked, but I have run that block since 1992) and the motor has been in the frame rails so far this year. How fast are you trying to go? I am running 6.70's @ 201-203 mph right now, I am going to run the Norwalk race in August so I will probably step it up just a little more. Email me if you want combo info.

 

IGO1320, I tried emailing you but you've got email turned off. I'll try private messaging. Thanks for the combo info.

 

tell you from my past...we ran 6.40 but always had head problems, I must say the best thing i have ever done is we and bought a brad /kb motor, now run 6.0 all day long and running that is on the concertive side there is a hole lot more left

 

Thats about my plans for next year, using a combo along those lines to ease into TAFC. One year to get into the swing of things, then step it up the following year. For now I'm afraid curiousity is gonna end up killing the cat in my trying to see just how far I can push this little SBC. I've heard that Jason Scruggs had been using a small block in Pro Mod and that only he and God knew how much boost he was pumping into his motors and was running in the 3's doing it! I'd love to twist his arm a little until he fessed up!

 

Rick, take my advice, I could have owned severl brad motors for what i had spent on running that small block....NEVER AGAIN...that hemi was the best thing i had ever done. good luck Dave Lowe

 

Blown SBC

Second wind,

Did you just have head issues or did you have bottom end woes also?, How hard did you push it to run 6.40's? Thanks

 

Just heads..kept brodix in biz...bottom end was never a problem ran all good stuff also ran a crank support from rcd.as for how far did I push it..TO THE MAX. ran a hihelix 10-71 port nozzles hat nozzles pump loop hi speed ect.with ever bit of 38# of boost. we kept the blower re stripped all the time

 

OK, now you guys are starting to answer my original question! 38# of boost ! And to think I was gonna be happy with 20 ! I'm gonna kepe this one in tact at where it is, maybe a few lbs of boost but I'm going to have to switch over to injection. I ran a four hole vert Hilborn in my Blown altered from '88-'92. Any suggestions on an Enderle setup? I know injection is much easier to make changes to than carbs...anyway it would be for me as I'm not a carb guru.

 

....and why the *(*&^ does my handle have a jr dragster by it ??????? ha

 

That depends on how many posts you post, (and im not studder typeing)

 

Oh OK, thanks. I guess we never stop being a rookie somewhere, huh ! ha

 

Jr dragster

I changed mine to my car number.

 

And how'd you do that? I'm more partial to hotrods than computers ! ha

 

Hell I Have Over A 150 Post And Still Listed As New

 

How did I do that?

This is bad.....I can not seem to figure out how I did that.....but obviously I did....old age creeping up on me I guess!

 

we run a sb in a ta/d and have a psi "a" and it makes 55 lbs and sorry i think the engine is very reliable, we strip it after every event and really see no serious problems we run our bearings for a season and change them out of guilt. We do have the head problem and mill the heads every second event but other than that really we havent hurt much since 1993 when we started, we broke a valve spring on fire up but solved that by spraying the valve springs with the torco mpz (i think its called) we dont use a huge cam (260) and turn it to 10,000, we still use 23 deg heads and the car is probably one of the quickest std angle headed cars in the world. Ok enough of that but Id have to say we are really happy with the performance and reliability best numbers are 6.03 @ 226.
But then again im probably biast and do love my Small Blocks (Chevs)

 

SBC boost update. Ran it Wednesday night using MSD's difital programmable 7 ignition to tame wheel spin. Finally got that under control off the line. Stepped up the blower, now running 24lbs of boost consistantly and not having any problems, other than spark plugs (see tech questions). OK, lets move on to the spark plugs you blwon SBC guys are using. Remember I'm using AFR heads. I just tried the new Iridium plugs at medium cold range. Any suggestions?

 

secondwindracing....Your combo ?

Could you give me your the combination your using...I'll start looking for something along those lines. Thanks