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8v flowbench hijinks

Can you describe what kinda flowbench setup you have? I know there are instructions on how to make them in various places just curious about your setup.

Might be fun to see what one of my BMW heads looks like.
 
why is a honda 4 valve head flowing 100 more ccm's than a volvo 4 valve head?

one is 1.6 one is 2.3? shouldn't the B234 head have bigger valves?

or am i totally missing the point...
 
I was in too big of a hurry to flow my new head.. It's still sad in comparison to 16v stuff. But I like the simplicity and ease of assembly etc. I've got some numbers for a stock 531 around here somewhere. I'll post them up when I find them.
 
531 is going to flow more on the intake side, but oughta be the same on the exhaust side (same port, valve size, etc)
 
also, sam dropped off a 2jz head yesterday, and I talked to a fellow evo owner about working on his head, should provide some interesting diverse info. gotta build a couple more bore adapters, might take the opportunity to re-do my b230 adapter since it kinda sucks..
 
played around a little bit with an intake port (man lots of casting quirkiness, I don't remember all of this), basically just cleaned up and did a light blend, the return was surprisingly... low. need to tool up and make a few more changes, perhaps tomorrow evening.
7.5% improvement at high lift, 4% improvement at max lift with the T cam, based on the numbers from the other night. It presently occurs to me that I should have checked an adjacent stock port to baseline, but oh well.
 
Could you post up a nice table of the info you find as you go along? That link that Gralin put up is wicked.

You're doing a wicked thing, wish I had the resources for this sort of ish. Keep it up.
 
meh, right now i'm just playing. I need to get the box hooked up to my laptop so I can play with the other features of the bench (tracking, logging, and graphing). that's going to require a little device to accurately set valve opening. hm.. might build that tomorrow before diving back into the port.

I also have found myself lacking of a couple bits that come in handy.
 
You ready to work a 16v head for me? I send you a good lower section you send me ported one back? Bah who am I kidding I still need stiffer valve springs.
 
dieselboy said:
You ready to work a 16v head for me? I send you a good lower section you send me ported one back? Bah who am I kidding I still need stiffer valve springs.
Click to expand...

rock auto to the rescue for that ;) (actually, I do have a set of them laying around here somewhere)
 
Volvo whiteblock heads are very similar. When I looked up the flow numbers (thinking my 9mm cam was still really wussy), I found that it flowed something like 94% of maximum at 9mm. Knowing that velocity is good for mixing, I think Volvo knew what they were doing when they spec'd 9mm at max lift, as it has good mixing, low valve train wear and nearly the same flow as higher lift cams. To me, the big advantage of a higher lift whiteblock cam (I think Fred said 10.5mm was max on the hydraulic lifters, but don't quote me) would be the duration, as the 9mm cams are pretty pointy.

As far as Volvo heads vs. Honda. Volvo's whiteblock heads flow around 200-210 on average it seems. My guess is they focus more on the intangibles than Honda, as they generally don't rev as high and have an extra cylinder. If you aren't revving to 8k, it makes no sense to have crazy flow at the expense of port velocity ect. Same goes with the 16V head, although it flows on par with a lot of other 4 banger heads (230-240 CFM). Worked over, the best 16V heads get well into the 300s (362 is the highest I've seen with 291 CFM average across the entire range...better than any 4 banger head I've ever seen). Highest I've seen for a Honda head was an H22 head flowing 347 CFM averaging mid 260s.
 
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food for thought eh. I haven't tested the v70 head I've got sitting here, need to build a bore adapter for it (and for the 2jz head, and I guess one for an evo head).

I don't like my current 230 adapter either, might do a re-think on how I build them. current one is MDF with a decent taper to the inlet, and I'm sure its affecting the readings downward.
 
messed around some more. ordered another bit this afternoon, one I thought I already had.. oh well. Got the unported vs ported difference up to ~ 12 % @ max lift on the awesomeness that is the T cam.

then I spent a little while crafting a rudimentary valve opening jig for 8v's. Did anyone else know that the bolt spacing for the cam caps isn't quite symmetric down the line? (goddamnit). A trip to lowes tomorrow should get me the long thread 8x1.25's I need to work it. I'll have to spend a little time rethinking the next one I build, since I've got a variety of heads I'd like to at least be able to play with; building one of these per would become tedious. got some ideas though.
 
looks about like this at the moment:
110259166.jpg
 
Kenny, sweet setup. I am in the process of building my own. Any pics of your adapters? Haven't got a clue how I am going to seal a head to it. I got half way through building mine, and the link stopped working. Looking identical to your's. They can be built on the cheap unless you get into the electronic end of things. I was going to use manometers and some complicated ass equations. You weren't so cheap:-P
 
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