Offshoreonly.com - Holley 306 SBF build

Offshoreonly.com (https://www.offshoreonly.com/forums/)

- General Q & A (https://www.offshoreonly.com/forums/general-q-20/)

- - Holley 306 SBF build (https://www.offshoreonly.com/forums/general-q/378087-holley-306-sbf-build.html)

couple of questions as I deal with a lot of sbf motors. why a 1200cfm throttle body? seems pretty big for a 306 inch engine. what are the thoughts on the promaxx heads? casting quality, machining quality out of the box, etc. they seem to be a good deal for a budget build if they are well made but I have not seen any of the ford ones yet. not really a question but a thought, with a stock block I dont think a whipple would be a good idea as the roller blocks are known to split down the middle but seems to be boosted or nitrous motors.

Quote:

Originally Posted by Rookie (Post 4855885)

This build is nothing extreme at all. (consider it a budget build) I originally bought the car back in 1995 when I was 21 and I have not driven the car in over 10yrs. When I purchased the car the only upgrades were a Superchip and a 4:10 posi. It was a blast and a little handful. 0-90 mph was always fun even with it's anemic 225HP. I'll have to admit I was Camaro guy until I purchased this car. The engine has been laying around the shop for 7yrs waiting for all of my boating projects to be completed. Seeing as I have never assembled a SBF before I asked my head/engine guy (Jim Valako) if he would assemble it for me.

Sounds a lot like me. Had two 69's and a 70 Camaro. Then I went to the dark side in 1997 when I bought my 87 Saleen. All stock and 99% original with about 45k on it now.
https://cimg7.ibsrv.net/gimg/www.off...a101f5557d.jpg

Quote:

Originally Posted by compedgemarine (Post 4856508)

My friend just bought a set of Promax sbf heads. A few of the spring dampers were broken. I have pictures of them, but still can't post for some reason(I'm working on it). Stock late model blocks are said to break around 500hp. Of course there are a lot of variables. Keep the rpms down to help it to survive. When i was running a Vortech supercharger, the stock rids bent before the rods cracked. Lol was around 500hp.

Quote:

Originally Posted by compedgemarine (Post 4856508)

Was going to go with the Hi-Ram intake until I found out I could not use my stock hood, so the the 90mm I bought became useless. Purchased the 1200 on a black Friday sale. Not really too concerned about it seeing I'm going MPFI compared to over sizing a carburetor. I have a 1000 laying around somewhere if needed, but it's not black and might clash. lol My builder has used dozens of sets of Promaxx BBC heads in marine builds and likes the quality. This is his first set of SBF heads and said that they looked good. He did some porting and said that they flowed out of the box close to as advertised.

Quote:

Originally Posted by Griff (Post 4856511)

Sounds a lot like me. Had two 69's and a 70 Camaro. Then I went to the dark side in 1997 when I bought my 87 Saleen. All stock and 99% original with about 45k on it now.

Nice Griff! I was talking to my head guy and he said that he probably ported, I believe, every Saleen Mustang head in the 80's. I think they would get skids of them shipped from California to port.

Quote:

Originally Posted by underpsi68 (Post 4856512)

I have pictures of them, but still can't post for some reason(I'm working on it).

Did you read the link in post 20?

Quote:

Originally Posted by cheech (Post 4856540)

Did you read the link in post 20?

Of course not lol. Thank you. I posted pictures before, wasn't able to the other day. Here's my car I have owned for 33 years. 353 Dart 8.2 iron eagle, callies magnum crank, oliver rods, 9:1 je pistons, tea tw 205s with n02 exhaust port, t&d shaft rockers, full manual aod, strange 9" rear- 3.25 gears, full weight 100% street car. Has a very mild solid roller cam. Very easy to drive. My son actually drove it (with me) day of the picture. Ran 9.41 @149mph at 3500lbs with single turbo as the car sits in the picture, small drag radial. Didn't take it to the track with twin turbo but added 400+hp on new combo. Should be an easy 8 sec ride.

Quote:

Originally Posted by underpsi68 (Post 4856590)

Brand new Promax spring. Supposedly made by comp.

Ouch, that's weird that new springs can be broken. Does he know the comp part #?