nice job on youre first porting! every flow bench is different. if you want to really compare #'s you would need to do a side by side test on the same bench.

 

sorry guys, I test at 28" like everyone else.

Make sure and zero out the manometer and flow scale and also check for leaks as the .100 lift flow # should be in the 62-68 cfm range depending on valve job angles and chamber shrouding. Just can't get more air from that size valve at .100 valve lift.

.200 lift should be around 132 and 144 cfm depending on valve job angles and chamber shrouding.

Having the flow #'s off this much down low can mean a leak from head to flow bench or the manometer or flow scale are not setting at zero when at rest. Could also be a bench that reads different than SF benches. Just some things to check out.

If all of this checks good, I would flow a stock LT1 head on the same bench with same test procedure and see what it flows through the entire curve and then compare.

I am sure the car will run much better as you did increase flow everywhere and the port doesn't back up until .650 lift so the port has to have the shortside pretty wide and laid back. Definitely a better head than stock, just maybe not flowing quite as well as you were thinking.

Lloyd

 

People play with bore sizing too. I have seen guys post numbers from Lloyd on a 4.060 bore. Aftermarket are often flowed on a 4.155. Other shops use a more realistic 4.030 bore. What bore were you using at school?

 

Guys....if someone gets a set of heads from AI or LE and they post good numbers, you will get a buch of guys saying the car should rock.

Here, we have a guy that does his own thing, gets good results and all I see is all of a sudden flow numbers do not mean squat.

See the irony there?

Flow numbers by themselves does not mean the car is going to run great, but they are an indication of how it can perform.

What most people do not realize is flow numbers with a head are just that, the head. How heads really work when you throw an intake on and have your headers in play changes everything. There are a number of dynamics that dictate how the head performs...this is why you can get guys with heads that flow ok that run very well and guys with huge heads that run ok.

Head flow numbers should be used to see if you are getting improvements with the heads and not as a comparison to another head...

 

I dont know, I see a bunch of people trying to help a guy who just flowed his first set of heads. I would appreciate the help if it were me, a lot of people knowing (seemingly) more than he does about flowing and trying to make an apples to apples comparison. Good job btw on the porting, I hope to do that one way, but there is no way to get better other than experience (and help from experienced people). I hope to see some track times/mph!! good luck with the rest of the assembly. My only question, why the mild cam?

 

deff run a bigger cam unless your trying to make it stealthy sounding.i got similar flow numbers w/ similar parts.what did you do to the area where the seat meets the head? i took mine down alot in that area and removed two coffee cups full of material from the heads and two and a half from the intake.us diy porting guys should start using the coffe cup as a standard mesurement for material removal,haha.nice work, and its good to see that the regulars on here didnt scare you away from trying to do somthing yourself!

 

the best thing about doing the port work yourself is that if you know what you're doing you save yourself alot of money. also you can keep on messing with them until you have some great flow numbers. of course flow numbers aren't everything just like dyno #s, yet the bigger the numbers are the better we usually feel about our builds. i wish i knew how the porting process was done. if you ever do another port job again take some pics if possible. if you do a little write up I'm sure it would be appreciated by most (keyword most).

 

thanks guys for the help/input it always needed but the reason for the cam is the car is going to be a dailly driver and anything over a cc503 seems to be to big for that, but im sure after a while i will step up to a cc306 or custom grind. but the motor will be done and in the car in about a week-week 1/2. and i will post a start up video and after a few miles i will dyno it, and then of course track ET/MPH. so i will keep yall posted.

Also my buddy is doing an lt1 also and he p&p his and this is what he got flow # wise
INTAKE LIFT:---100----200---300---400----500----550----600----650
FLOW SCALE:----3------3-----4------4------4------4-------5------5
% of FLOW:----51%--94.5%--65%--78%----87%---91%---62.5%--62%
CFM:---------75.5---139.9--191.2--229.4--255.9--267.7--275.6---273.4

what do you think of his? and yes i agree flow #s really mean nothing to power

 

I think you did good. Get it together and see how it runs.

Good luck with it.......glad you didn't hit water or put a hole in the head

 

thanks mdacton.. my real goal is just to hit the 11's but still be a DD.
but like i said the car will be done in 1-2 weeks and i will post the first startup video and A/F ratio specs and i will follow up on track times/dyno

 

well, you may be able to squeeze high 11s out of it, not sure though. I wish you the best of luck though. Id prefer to see somebody that does stuff their self do better than somebody that bought stuff done.