Please translate this flow sheet!?!

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myasylum

myasylum

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I just ported my first set of stock heads myself. I have no idea how good I did. I had someone flow test them and they wrote done the results. When I ask him how good it was he just said, "It's ok." and thats all he said!

What is this telling me?

Is this bad?

Thanks!

flowhead2.jpg
 
Hate to tell you but those #'s are barely better than the stock numbers my X heads produced. Did you have them tested before you did the porting? If so did you make a gain? I always flow before and after so I know if I'm doing the right thing. Also flow benches vary from place to place so there's another reason to test before and after.

What all did you do to them when porting? Can you post some pics of the ports and valve bowls?

Also is it a good multi angle perf. valve job? A good valve job can make a big difference. Made nearly 20 cfm diff on my X heads.
 
Well, at least "barely better" is better?!?!??

Yea, it has a 5 angle grind. I can't take pics because the heads are at the shop.
He said he was going to test them before hand, but he never did? I didn't pay for anything either, so I don't know? I ported the intake and exhaust, and bowls, I took quite a bit out.
Could you maybe post some pics of ported heads so I can see what they are suppose to look like??

Thanks much!!
 
did you leave the intake a bit rough? or make it shine? What heads were they?
 
myasylum said:
Well, at least "barely better" is better?!?!??

Yea, it has a 5 angle grind. I can't take pics because the heads are at the shop.
He said he was going to test them before hand, but he never did? I didn't pay for anything either, so I don't know? I ported the intake and exhaust, and bowls, I took quite a bit out.
Could you maybe post some pics of ported heads so I can see what they are suppose to look like??

Thanks much!!
Click to expand...

Ummm where did you get the info on how to port your heads in the first place?? Very important to know what kind of head they are too. That would be pretty decent for a set of 318 heads haha
 
Well you can't beat free flow bench work but it would have been nice to know the before so you knew if you made headway. It's always possible his bench was real stingy making it look like they're not flowing all that great. I'm not a professional by any means so don't' take my word as gospel. I have done about 5 sets of heads is all. Here's 2 pictures of the work I did on my X heads. I had some more pictures but I can't find them. If I run onto them I'll post them.

Here's my flow #'s before and after on my X heads

before int/exh.--------------After int/exh.

Lift
.100-60/50--------------------64/51
.200-120/102-----------------129/105
.300-167/131-----------------188/135
.400-200/143-----------------236/155
.500-205/146-----------------243/165
.600-200/148-----------------250/170
 
hi what kind of model flow bench?? what was the test pressure? test pressure makes all the difference in the world showing flow numbers. high test pressure will show very high results. this is what most people want to see!! regardless if it's correct!! lower test pressure is more real world!!!
high flow numbers sell. just food for thought.
 
Sorry man, but those numbers are no better than stock.

915J Stock,

Intake 66 123 170 206 220 216

Exhaust 63 110 135 145 148 148
 
Yeah, it looks like there are problems. I would have expected to see that from a set of used stock heads. Not ones with a good 5 angle. All is not lost, but I think you may have gone a little farther than you should have. If you want a real critique, post some pictures of what you did. Maybe we can tell you what not to do, or what might help now.
 
What do you mean? "All is not lost"? As though, it will still work?

It is a J head, 1.88 machined to 2.02.

Here is a picture of the machine that he used.

thanks.

Portsmall.jpg
 
My set of 318 heads (302 casting) with the small valves 1.78 intake 1.50 exhaust with no port work done. Just a good valve job with back cut valves.

.100 76 77
.200 111 113
.300 175 122
.400 201 126
.500 204 128

It would seem your numbers should be higher with just the bigger valves. Your exhaust is flowing better than mine that's for sure.
 
It's not the bench that flowed them. Rather the tech and the weather that makes or breaks a flow test. It's not like a repeating on or off light. Which is why I put very low faith in flow numbers alone, regardless of who does them. And also why very high ones to me indicate an issue, rather than an engineering breakthrough. What I meant by all is not lost is that if you made a blunder in one area of the port it will kill the numbers. But if it's only one area, there may be things to do to make the "oops" less of a hinderance. A typical bowl job for me incudes an intake gasket match that blends down 1/2" into the port, a very slight increase in the pushrod pinch width, and the bowl work without touching the guide boss. I can get around 240 out of that (a low average). Making the bowl bigger hurts without giving the air more area to flow thru to get there. It's about airspeed, the right amount but not too much, and the air is supposed to slow at throat area and then pickup thru the bowl. Think of a race car going into a turn. You want it moving as fast as possible, then braking just enough at the right time to make the turn but be on the gas before you exit it. That's good for making the air turn into the cylinder but too much area and no venturi near the seat means it looses momentum and doesnt have the speed and just dies. That's what your test looks like happened without seeing any pictures and hearing your description.
 
74, Thanks for the vote of confidence. I appreciate the thought. However I don't make my living off this work. I do it to augment the bills and because I love it. I have a few customer jobs already. Two engines (one just starting and the other in planning stages) and a hood and trunk I'm currently fixing and painting. Plus I have my farm and my own cars/truck to maintain. I see you're in central CA. I can suggest Brian at Indio Motors (http://www.immengines.com/) or Angie if she's still at Mopar Engines West. Brian would be my first choice. VERY, very sharp cylinder head guy there. He's close by too.
 
Just because I thought I'd post the only pictures I have for now. I guess this don't say much, huh??

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The intakes have more of a problem but the exh look like you madde the too big anyway. Exh wants "smooth and small". You dont so much enlarge as re-shape them. So post close-ups of the bowl areas, if you can the short side turn, the port entry, and the valve you're using.
 
the 1st pic seems to show the air injection bosses on the floors aren't blended a whole lot, and I would open the width of the exhaust floor where it pinches at the exit.

need intake manifold side pics of the int guides and bowl pics of both sides.

But seriously, if you had a bowl cut along with the seat/throat cut for 2.02, just grinding out the roof kink and minor guide profiling would get 232ish cfm.imo
 
O.k. After looking at some pictures of how the pro's do it it's apparent to me how much I suck. I'm almost embarrassed to post these. So don't be so hard on me.


The thing that gets me, is the guy that did the flow chart helped we with the heads, and said they were "fine", and I built him a small web site for it. Why do I always feel like I'm getting screwed?

Are there repairable? At least they aren't worse then stock!

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sadly, I am unsure of what a "intake runner" is? If you mean the part of the head the the intake manifold is attached to, I didn't touch those. I just mainly did the exhaust port, and inside the lip of the hardened seat of the intake.
 
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