a follow up to this post

http://www.slantsix.org/forum/viewtopic ... alve+seats

over the past few months a former engineering co worker and I have invested some time and a few dollars in
working to get a slant head that at least matches what Mike J had produced. Mike was good enough to send his
data sheets along with the hard test equipment, so there is some evidence of what he was getting, concerning port flow.

I did not get the actual valve seat and port tooling. It is one thing to talk about what one was doing, and it is something else to
reproduce it.
There has been progress made, after a stumble, the last test gets what Mike J did with the same sized valve.
There are two files attached, the first one is a capability-repeatability study of the machine, the SuperFlow 110 and the operator, me
To do the flow improvements, I have been using the same peanut 87 hydraulic head. The exhaust ports were cleaned up, 45 degree seats
put in and not touched again. On each iteration of the intake port I re tested the same #3 exhaust port to get a base line on the repeatability
of the setup and the flow results. The system is extremely repeatable. Over four unique tests, from June of 2018 to Feburary of 2019, each with
a complete tear down and a new set up, the test to test variation for a given valve opening was in the worst case 2.6 CFM and was typically less than
1 CFM.

The second file deals only with the #3 intake port,
6/20/18 was the test after the initial porting with 45 degree seats.
6/22/18 was the test after going over the port and fine tuning the contours and finish.
9/16/18 was the initial test with the 30 degree seats, little was done with blending around the actual seat.
2/15/19 was the most recent test of the 30 degree seat, additional blending around the main 30 degree seat.

pay attention to the CFM Sum value, from what I have been told, with a 30 degree seat one can expect to pick up flow
at low lift values when compared to a 45 degree seat. And then the 30 gives up some flow at higher lift.
To evaluate that, I copied what Mike was doing here to look at 'total flow', but I am doing it with a single value where Mike J
used a chart.

The head that was the subject in the above studies will go on the shelf for now.
I have another hot tanked and magna-fluxed 87 peanut head at my friends shop, there is more to do here.

_________________
Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

Do you have a feel for what those numbers would translate to at 28 inches?

I'll say this ....my 225's head (like all Slant Sixes) has small ports. But they are probably the nicest of any factory casting I've seen. I thought about cleaning up all the rough areas but...there really weren't any. Their small size, and length, is their downfall, at least from a max power standpoint.

see the second sheet, far right column

_________________
Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

Thanks for the work and the careful data collection, John. One thing we see from the rightmost INT data is that there is no point running a larger cam than mid-high 0.400s in lift, at least for that port. That one is almost identical to the head that Mike did for me that is on my turbo motor. I think he used 30 deg seats there and I am running a small (MP 0.436") cam as of now. I had it flowed at 28" water at one point.

Best,
Lou

_________________
Home of Slant6-powered fun machines since 1988

That is 'fo 'sho.

Greg

_________________
http://www.youtube.com/hyperpack

Amen to that.

Lou

_________________
Home of Slant6-powered fun machines since 1988

Personally, I am glad John took over the reins from Mike. I'm sure that sooner or later one of my heads is going to need freshening, and it's nice to have someone I can trust to do it.

_________________
Official Cookie and Mater Tormentor.