Porting a type 4 head, Not much of a short side Options

[Shivers]

Because the port is almost straight, with little long side short side concerns, with what there is , do you find it necessary to slow the flow down on the “short side” to get good flow out of the valve. I was reading about something mepstein posted a picture of. Small divots, like a golf ball. So I’m going to do that on the long side, just wondering if there is any reason not to also do it on the short side. Thanks guy’s (IMG:style_emoticons/default/smile.gif)

[brant]

I used to run the same AJRS heads in the 1990's on a type 4

38x48, thin stemmed valves, Dual valve springs, and titanium retainers with holes drilled in them

[Charles Freeborn]

I used to run the same AJRS heads in the 1990's on a type 4

38x48, thin stemmed valves, Dual valve springs, and titanium retainers with holes drilled in them

Allen is quite the wizard. The most impressive (to me) aspect is the weld build up to allow porting. He cut o-ring grooves in the mating surface of the intake manifolds...
I'm not sure of the valve stems I had, definitely not lightened retainers, but dual spring. Very well thought out and executed.

Very nice guy too. I spoke on the phone a couple of times. Got some parts, etc. Old school honest.

[Shivers]

I used to run the same AJRS heads in the 1990's on a type 4

38x48, thin stemmed valves, Dual valve springs, and titanium retainers with holes drilled in them

Allen is quite the wizard. The most impressive (to me) aspect is the weld build up to allow porting. He cut o-ring grooves in the mating surface of the intake manifolds...
I'm not sure of the valve stems I had, definitely not lightened retainers, but dual spring. Very well thought out and executed.

Very nice guy too. I spoke on the phone a couple of times. Got some parts, etc. Old school honest.

Thanks Charles. (IMG:style_emoticons/default/smile.gif) The RPM's must have been impressive. How did he get it to breath out as well as he got it to breath in? That exhaust port, especially the 2.0 heads have little that can be removed. Did he weld those up too or is it big valve, massaging the port right after the valve and polish...Kind of hope for the best? Some of the work these Guy's do is real magic

[Charles Freeborn]

I used to run the same AJRS heads in the 1990's on a type 4

38x48, thin stemmed valves, Dual valve springs, and titanium retainers with holes drilled in them

Allen is quite the wizard. The most impressive (to me) aspect is the weld build up to allow porting. He cut o-ring grooves in the mating surface of the intake manifolds...
I'm not sure of the valve stems I had, definitely not lightened retainers, but dual spring. Very well thought out and executed.

Very nice guy too. I spoke on the phone a couple of times. Got some parts, etc. Old school honest.

Thanks Charles. (IMG:style_emoticons/default/smile.gif) The RPM's must have been impressive. How did he get it to breath out as well as he got it to breath in? That exhaust port, especially the 2.0 heads have little that can be removed. Did he weld those up too or is it big valve, massaging the port right after the valve and polish...Kind of hope for the best? Some of the work these Guy's do is real magic

People with more experience than me can better explain, but as I understand the GT5s class was not weight limited so it was largely about light weight. I think that car weighed around 1800 lbs. The engines were limited to stock displacement so it was that. Stock 2.0 crank, rods p/c's. All lightened and balanced. Lightened flywheel. It only had a 4 point cage so I couldn't run under the GCR classes.
Hi revs were not on the menu. I had the limiter set to 6k. The T4 was essentially a VW Bus engine engineered for low rpm / high torque. It pulled like a mule between 3500-5000.Above that it just made noise. Getting high rpm out of pushrod engines can get expensive in a hurry, not to mention explosive. Itwas a fun car, but hard to find a race class for. I did add more to the cage to get it past tech, but at 2.0 it fell into a no-win class (VP2 or EP) which isn't a fair fight against modern cars. My current engine is a 2.6 which may be comptetetive in VP2 on certain (technical) tracks, but even there it'll be a struggle to keep up. If I stay in this game for any length of time I'll look for a 1.8 to build out and run in VP1. That could be really fun up against the other small 4 cyl cars like Sprites, etc. That displacement, properly done, could achieve some higher RPM numbers. We'll see...