My W2s flow 320@.700. When Ryan ported them in 2015 we asked about a larger valve and he didn't think it was worth it. That may or may not be true but they seem to flow well with the 2.02.

It’s easier for me to see the numbers side by side-

Lift—before - after
0.050 - 030 - 039
0.100 - 060 - 066
0.150 - 093 - 100
0.200 - 124 - 132
0.250 - 153 - 165
0.300 - 178 - 192
0.350 - 205 - 217
0.400 - 231 - 244
0.450 - 252 - 267
0.500 - 271 - 277
0.550 - 288 - 291
0.600 - 300 - 294
0.650 - 305 - 291
0.700 - 292 - 288

Thank you fast68plymouth, I should have summarized it in such a manner in my update.

Oh, without a doubt I very much understand that what I am asking for here is near impossible to trully accomplish over a thread posting. I am also certainly of the understanding that at best these are recommendations which are not "set in stone", so of course caution is requird. In other words, anything I do do these heads is entirely on ME!!!


This actually is very similar to what the flow guy described to me.

He made some recommendations on how to best deal with the floor hump, or one could probably better describe it as a ski-jump given how the floor takes an immediate drop towards the valve seat right after. So that description you provided seems to be spot on.

Sometimes, as you start finessing the SSR in an attempt to help the high lift numbers........ you find that in order to realize those high lift gains........ you end up giving back some low/mid-lift flow.

Or... you start going for improved high-lift gains and the end result is the port pretty much goes backwards everywhere...

I hate when that happens

You can find very good higher lift flow #'s by working the short turn and the chamber around the valve circumference. Highly recommend 2.055 intake valve...Manley Race series will handle 13:1 and solid roller spring pressures for quite some time (years).
Brian

OK, getting ready for the weekend here as that is probably the only time I can take a shot at improving these a tad more.

Q1 - Re: the exhaust port roof guide hump, am I getting a YEY or NAY kind of an answer here gents? LOL

I am asking literally some suggestions as to whether I should even attempt to touch this or not? Seems like just a chunk of metal that only supports the guide while at the same time restricting air from passing through the port.

Q2 - Re: the intake port roof, I am going to remove some metal there to give the turn a longer and rounder turn towards the valve...I think there is space there, my thickness checker will come in handy here, is there anything here to really worry about? seems like a straight path the only obstacle being the head-bolt passage...

The plan is to do one cylinder, do a final flow-test and either replicate, or find a hole somewhere to hide in case I mess things up!

Thanks everyone...

if raising the intake roof be careful where the cut for the spring pocket is, not sure on your heads but most are very thin there, ask me how I know LOL

The trouble with a lot of these heads on the exhaust side is the shortside has what I call a “Herman monster forehead” that over hangs into the bowl. It’s been awhile since I’ve touched a W2 but on Speedmaster, Edelbrock, etc, this area needs pushed back, widened, and then shaped. This save the exhaust air from going around Herman’s forehead and out the port.

What is sufficient thickness to leave here?

I'm running the CompCams beehive springs, part# 26056, 400 lbs./in. rate, 1.100" Coil Bind Height, 160 lbs@1.800", 420 lbs@1.150". Can't imagine going to a much higher pressure than maybe 550-600 lbs in this street application.

I should be able to gauge the thickness with either my ultrasonic tester.

based on this article, i think you might be close to what should be expected...not sure how much I'd be willing to mess with it

https://www.motortrend.com/how-to/mopp-0111-porting-the-magnificent-w2/

Small update re: flow numbers.

Here are the INTAKE and EXHAUST port flow compare charts: legend is self-explanatory, they are all my DIY efforts, while the Dulcich is the MM article from years back, sort of using that as a DIY baseline to compare to.

I decided to "take it easy" at this point in time, meaning the last thing is to blend the valve job machining ridge in the chamber to the rest of the chamber and that's going to be it I think.

Now go out and have some FUN.

So a bit of an "oldie but goodie" (in my book, heck, my project right? lol) update!

I figured I would post the finishing details here, in particular the port work as strangely enough when I was originally looking for pictures of prior work it was somewhat difficult to find...I'm talking close-up details, etc.

Take it for what it's worth, the LEGEND to track through the changes is as follows:

1) STOCK - this is the as-cast flow of my W2 Econo castings
- the only downside is that this was done on a different SF-300 bench, whereas the remaining testing was done on a different SF-600 bench

2) MP Template - result of me following the W2 MP porting templates

3) Valve Job - result of the machine shop doing a standard three angle valve job and a bit wider chamber wall cut to deshroud the valves

4) Blend - result of my additional porting work on SSR, and further blending in the chamber deshrouding cuts

I'll post the comparison of flow results first and finishing pics in the next update.

...and here are the finishing pics

...finally the chamber

1st thing is I don't know how you can install a set of liners and the valve seats still be concentric to the guide. When you do the seats whether it is stones or cutters that tooling always centers from the guide. Just a couple thousands off and they will leak air. And just from the photos the blending of the seats into the chamber will gain you 10cfm from my experience such as it is. And if the valve throat is not the proper diameter, then you also are leaving flow on the table. And while flow numbers are an indicator, I have found that using a bench that measures the speed of the air especially over the short turn is really helpful. While 28 inches is a standard, actual flow in the heads in a running engine is more like 60 inches. I can flow most heads to 35 inches with my bench and I usually crank it up at max lift just to see what happens. A short turn that has more than about 400 feet per second at 28 inches many times will actually loose flow if you flow them harder many times.

So for what it's worth here is the sequence of how things were done:
1) the original shop installed the liners to take the stock 3/8" down to 11/32", the head retained the MP supplied valve job at that time
2) the flow shop suggested that the valve job should be re-done, and for what it's worth, my DIY test of dropping the valve in freely and listending for a nice "thump" vs "boing boing boing" sound (as the valve bounces off of the seat since it's not concentric) did confirm that the valves were much better after the valve job

Having said that, I am not sure how to interpret what you shared. Was that the wrong way of going about it? Should the 1st machine shop have insisted on doing a NEW valve job and only done the guide liners afterwards???


Oh, this is interesting. So I had actually done a good amount of work on these already to remove the shart transition lines left over from the valve job. There are literaly very little, if any, sharp edges left. Very close to the seat I do have some of the orignal casting still showing, which is why you can see some of these little bumps in the surface.