Scotty Brown CNC alum 350 head porting

you need to make 2 1/4 headers that go over the chassis like the old 57 chevys. a little bit bigger makes a big difference.

 

So every one needs to order at once to blow this out
and 2 1/4 headers for this guy^^

 

Yep just like 283 pistons.

 

2 1/4 does nothing for zoomies. wish it did. run 2'' now. need the back pressure from all the piping.
i didn't know you guys don't run 283 pistons....

 

Scotty is getting 237 exhaust cfm, I would think the heads would love bigger headers.. Whats the most exhaust cfm has anyone seen on iron heads?

School me please..??
Isn't the average preferred intake to exhaust cfm ratio 70% to %75?
These Scotty's heads are around 80%.
I know rpms are liked at the track so these heads with only 350 ci. at 237 cfm exhaust should be screamers?

 

How do we know if the heads are ported that much if you will gain that much power with the small bore isn't there a limit you can go before the engine just can't suck in that much air?
There is no dyno testing with ported, non ported and max ported. 235 on the exhaust means there is probably 300 at the intake. Is that much needed for the max effort 350?
You would need 12.1 probably to take this in.

where did this 237 cfm exhaust come from I have not seen this but this is an obscure thread no one knows anything, and no one wants to talk.

 

I think this is all pretty easy engineering calculations - The guy on "Engineering Explained" on YT could do this on his whiteboard. Maybe @Stevem will chime in. He seems to have a good handle on this type stuff.

Wouldn't it be fun to have a dyno for a couple weeks/months & lots of parts to play with! I bet we could get these little tree-fittys hummin'!

I'm considering building an E85 350 for the streetable compression.

This is what makes Buick 350's fun/interesting. There's so little known and I think so much unleashed potential.

 

It's on the first page of this thread. There are 2 from Scotty Brown..

Post #10 and #14.

 

One chart is with the small 3.80 bore and the other with a 4.00 in. bore or estimated at 4.00??

 

Nobody will run .750 valve lift. You need the largest roller cam core at .365 and 2.0 ratio rockers to get .730 valve lift.

 

Those are good numbers there buddy!!

 

Who says iron heads suck LOLOL

 

The flow flattens out after .450 lift (.400 on the exhaust) so not gaining much with high lift - Need long duration like the NHRA guys run.

 

Want to really compare the two heads look at flow numbers between 100 and 300 lift that is when flow really starts.

 

Yeah they are good numbers!

I did forget to mention the high .750 lift on the TA's. I think I was psychologicly thinking the BBB Tomahawk block that would make them work
So it will take a new aluminum block to get the most out of these heads??

Still decent numbers to .650 if doable?

 

There is not a person here that will attempt to run a 600 lift cam in a 350, I just don't see that here most here are not even going to get close to this big of a cam.
I see only about 4-5 people on here that will go past the 550 lift number on a 350 cam and who has a 245 255 @.050 beside me Mart and Demko?

 

int .554, 279*, exh .565 283*. but with 1.65 rollers it gets a little bit bigger.
maybe one of these days i will check piston to valve clearance. lolol

 

^^^...at least .050

 

Close enough. Finished block assembly last night just need to get fuel and ignition sorted out. First nice weekend on LI taking my new girl out for a cruse so not much getting done this weekend.