It is good to see that it looks like the valves and seats are basically fine. On a modern valve machine, the better ones can cut them straight with a surface of 5ra, which is a lot better than I am going to do with lapping paste that is like sandpaper. I'd double check the guides and make 100% sure that it is the top of the stem that is all that is wrong.

My boss would come down on me like a ton of bricks if I handed something like that to someone, as well he should. I now only use used SOHC valve shims on my own stuff.

I'd probably fix the valves, get the head lab cleaned, and deck the port surface and head surface and send VPD the bill. BTDT (not with VPD, but yeah).

I checked the top of the valve stem and it was out (checked with a square), so it will go in for repair. The valve guides are fine and nothing is bent from what I can see. The packaging was a little primative (pieces of boxes etc) and the rough handling of UPS has given me a little dent to fix on the bottom of the head (it is really minor).

To be honest, I'm looking forward to getting the rest of my parts and being finished with all of this. I'm normally more of a pain and would raise royal hell, but with VPD there is little point (remember I've called him week after week for months - you get a sense of things). I've adopted a more relaxed attitude to this - we'll see how it runs and have a crack on the dyno then see - if it works as well as it is suppose to then I'll only comment when people are looking for opinions. If not, then I'll pollute a few accounts of my troubles. I'd rather stay positive about this and not whine forever - just not my style.

Just ran into this.

I am not sure if I have all the screen names correct, but I am about 66% sure I offered in passing to do up a b20 head. I built a bench (actually my sister sort of did) of wood, with a replaceable top surface, specifically so I could port heads. Honestly it's outside, and I would not consider there to be any problems based on the photo with regard to the deck or valve cover rail not having been remachined... so maybe we are not on the same page...! As for the manifold face , just below exh port 3 looks like it might have a little more roughness than I would let pass. The porting, particularly in the intake bowl, looks excellent. (& I should point out that about 10% of my 11,000 Volvo photos are of porting...). The exhaust looks... functional, a nice quick money maker job by someone who knows what he's doing.
Also that's the nicest intake valve-back contour I have seen. The exhaust valve looks nice too. It's a matter of personal taste, but I'd never push someone to go with bronze guides when inserts are (IMO) as good. Also a matter of taste is retaining the 3 groove, freely-rotating valves.
I think with your knowledge base and craftsmanship you may be over looking how (HAD IT BEEN DELIVERED IN A TIMELY MANNER ) it might be a reasonable value to someone who doesn't want to learn porting, doesn't have the tools, the hand skills, shop etc. Of course to someone like that, the head would have had to have been delivered perfectly clean and ready to bolt on...

My big concern is that the chambers are stock- there's hardly even a rounding of the edges either side of the plug, and to me that is *the first* place to start modifying a b20 head, because it's so easy.
You've got the fuel (and a good portion of the air) hitting a wall opposite the port.

There are deficiencies in the head that don't come out in the photo's, there are variances in the valve heigts that are evident on the inside as well. I agree, there is nothing fundamentally wrong with most of it and I'm planning on running it pretty much as is, but the reports on the net about VPD quality and workmanship are a little overstated.

Had I known about this group at that time, I would have done it myself, but hindsight is 20/20. I'm quite certain that I could do a nicer job of the head and I think my collection of tools and skills could do the job!

So what should that wall of the port bowl look like? I've got an idea from what you've said, which makes perfect sense, but I've never seen one done. I also don't want to cut into the quench pads very much, as that defeats the purpose of having quench pads, but a little rounding may be in line.

Port bowl looks good (maybe you mistyped, or it's a nomenclature issue, because in context it sounds like you got what I am saying).

Valve heights, smalve heights... Did I tell you I accidently ran a washer under one of the rocker pedastals for a very long time? (studs rather than bolts retaining the rocker shaft and assembly in a horribly lit shelter I was paying for by the hour). As long as you set the lash... (I did, but believed the new cam was ground on a different base circle at the back, for some reason... )

I think quench is more than a bit over stated- it's nice, but to be the focus of an engine build like some of the kids on TB think of it as, is silly. Displacement, valve lift, cam duration being suited to what you do with it, CR& duration being in sync with each other... all kinds of basics make power ahead of the small effect quench has.

I'm talking too much. OK.
Basically, the air forms (more or less) a cone around the valve, as the inertia the air has (taking it across the back of the valve) is counteracted by the fact the air is being pulled in [tends to cause the well documented effect of the air taking the low path: the short side], so the effects largely cancel out (especially on the b20 head which has a decently tall intake bowl, and, arguably, a problematically tall short side).
At a combination of open throttle+high RPM, you are going to see more air pass the long side, and at part throttle you will see the reverse.

You most likely knew most or all of that.

Fuel, being heavier, is more likely to take the long side (ie. its balance of inertia-to-pull being different due to density).

So the important part to shape smoothly is the quadrant opposite the intake port. Personally I think you should take *a lot* out of there, even if it means paying to have the head milled substantially to shrink your chamber volume back down (actually a good thing being that it tends to "unshroud the valves vertically")

That said, there is new information the last few years that the NASCAR and esp ProStock guys have been privy to for quite some time, indicating that there is a very nice quench effect available that is lost on most porters.... [possibly the best quench effect], that being that the slim area between the intake valve and the bore (90* to the port centerline) should be left as quench area if the head has material there. The idea is to create a push away of gases near the intake valve rim, which is where detonation/preignition begins. So, ideally, go "long", not "wide" on the intake side, if you follow. You might lose a few CFM restricting the cone of flow there, but your burn is so much better...

One of the thing I have been meaning to do is load a couple hundred pictures to Flickr- the site enable call outs to different points on the photo.
While I don't have all the answers, I think it could become a great resource, and place of discussion [viewers can, in turn, call-out points on photo]. Maybe someday.

If you want to email me @ iadr@hotmail.com, and can accept a large file, I'll ZIP you up a few hundred photos you can look over. I don't know how available I can promise to be to answer questions, but the photos are sequenced by the main focus of each photo: chamber, intake, and exhaust, and within that by "effort"[ie. how much changed from stock] on a scale of 1 to 5, so are to some degree self-explanatory

BTW, having slept on it, I think that between the customer service nightmare, the fact that the work is at least as much done on the intake as exhaust (which differs from initial 'offer', as you noted), this was a nicely ported head that he had available to ship, not specifically one made for you. Not a bad thing, though, you may have gotten nicer port work than "intended".
Again, I am rambling, but the point I was going to make is that it looks suspiciously like he did a stage 2/3 port work, and never got to the chamber and just decided to ship it... so chamber work is hardly a rethink of the head, merely finishing it!

As a side point, I'd also have a machine shop enlarge the pushod holes, or offset them to the rocker shaft side, because increased rocker ratio is the way to go.
Not to rethink the project for you, but displacement addition and getting the cam right for what you do, and running maximum rocker ratio are, as a package, much more effective than porting.

Port bowls...I can't believe I typed that - most here can attest to the fact that my fingers don't always move as fast as my head, and if I'm sleepy I'm useless. I was thinking combustion chambers - I think I get the idea, but will drop you an e-mail. In the spirit of getting the information out there, I'd like to keep the group up to date on this part of the engine build.

As far as the level of work done by VPD, I'd agree - there was more done than was discussed, but this is the casting that I sent him. I'm not sure what his stage 2 or 3 looks like, but in all of our conversations the intake work was to be minimal. I'm guessing he just sort of forgets what he is doing an does what he likes, that and he is a very fussy sort of guy, so if he didn't like the flow numbers on the intake, he may have done it just because he was there. Who knows.

Back to my head.



I understand what you're getting at, but am unsure of which quadrat to be modifying. I'm guessing it has to be away from the spark plug hole as there is no quench pad there anyway. Thoughts?

By the way, my hotmail account will accept larger files and my addy is craig_coburn at hotmail dot com

I doubt he flows every head anymore.
In the late 80's through late 90's, Richard Gordon's son did almost everybody's heads on the west coast, and he's never had a flow bench.
According to Parker when I talked to him 10 years ago, he figured Rob was just copying what Dan Baisley had done for Richard when Richard actually had a - for the time- serious development program, when he was racing. When Cameron Louvre and Shane Greene were at IPD, they had tried to get Baisley to do a head again, but no luck, too much real business to deal with! I believe the extent of their success was that Cam's "supercharged head" was flowed there, but only after having been "done" (with limited success) elsewhere.
I think once you see the photos, you can see that once you establish where you are headed with a pkg of modifications to a head, and you understand at least the basics of port design, it becomes more of a just knock-'em-out sort of process than people seem to think. 3D sculpting of cast iron isn't for everyone, either, mind you...lol.. but flattery aside, I have a feeling you'd do OK...



Referencing the above photo: quadrant from 6 o clock to 9 o clock, specifically from about 6:30 to about 8 o clock, and you want to encourage a downward & counter clock wise spiralling into the bore of what flow may be blowing "across" the back of the valve into that zone.
BTW, it's between 8 and 10 that you do not want any material taken away.

I'll try to pick out some files to send!

OK, I think I've got it...I'll have a go when I have the head apart for cleaning before installation.

If anyone else feels an interest while I have the files copied & divided up into a half dozen groups and Zip'd, let me know. I'll probably just delete the zips after a week, as they are duplicating what is filed with its own order in other folders.


Also, I should note where I wrote above, "counterclockwise and downward", that references that specific viewpoint, & of course the mirror image cylinders will be clockwise...two of each.

2 years for a head..
who forgot about it..
caution when filling the head,i'd be right pissed off.

Yes - 2 years. I was on the phone every week for the last 5 months. No worries with filing - things should get started next week as I have to get my brakes mocked up this weekend.