View Full Version : Good Head
rmcdaniels
03-13-2006, 12:33 AM
I got my head back yesterday, RLZ completely reworked it for boost, all new oversized valves, new valve seats, different valve job, bowls and ports reshaped and blended into the seats, .004 shaved off of it, it looks like a new head.
http://s115271005.onlinehome.us/images/ghead431.JPG
http://s115271005.onlinehome.us/images/ghead432.JPG
http://s115271005.onlinehome.us/images/ghead433.JPG
http://s115271005.onlinehome.us/images/ghead434.JPG
http://s115271005.onlinehome.us/images/ghead435.JPG
http://s115271005.onlinehome.us/images/ghead436.JPG
AgressivMX3
03-13-2006, 12:36 AM
Very nice man. They gave you great head.
Looks good... but the intake hole you posted the pic of looks awfully rough. Why didn't they polish it?
looks nice. Do they throw them on the flowbench afterwards?
you want the intake ports to be a little rough...
you want the intake ports to be a little rough...
Word.. good to know. Why is that though?
rmcdaniels
03-13-2006, 12:50 AM
looks nice. Do they throw them on the flowbench afterwards?
I don't know if he flow benched this one, he didn't give me the sheet if he did. Brad at RLZ has a really nice flow bench though, so I assume his designs are tested. This is essentially the same design as another head he did that made 600 WHP on 24 PSI, but he made the exhaust a bit bigger because I run a supercharger. Brad says most of the flow improvements are gained in the valve job and the work just behind the valves. His valve jobs are pretty odd, they are fully radiused and smooth as glass. I've had a couple of other shops take a look at them and just shake their heads.
Slow96GSR
03-13-2006, 12:51 AM
RLZ got a web site?
I don't know if he flow benched this one, he didn't give me the sheet if he did. Brad at RLZ has a really nice flow bench though, so I assume his designs are tested. This is essentially the same design as another head he did that made 600 WHP on 24 PSI, but he made the exhaust a bit bigger because I run a supercharger. Brad says most of the flow improvements are gained in the valve job and the work just behind the valves. His valve jobs are pretty odd, they are fully radiused and smooth as glass. I've had a couple of other shops take a look at them and just shake their heads.
Thats sweet!
Word.. good to know. Why is that though?
fuel atomization.
rmcdaniels
03-13-2006, 01:02 AM
Word.. good to know. Why is that though?
Borrowed from Mototune:
The intake port is going to flow both fuel and air. The problem with fuel is that, since it weighs more, it's difficult to keep it evenly mixed with the air as it follows the contours of the port.
Boundary Layer
The next time you drive a car in the rain, notice that when the car is going 60 MPH, the rain drops go up the hood of the car at walking speed. That's because the smooth surface of the car creates what's known as a boundary layer, and the portion of that layer of air that's nearest to the surface is almost still.
The same thing happens inside an intake port. Except instead of raindrops, it's fuel droplets that will run down the port wall slower than the air. That causes a serious change in the fuel air mixture by the time it reaches the cylinder, ruining much of the engine's potential power.
Polishing the port walls will ensure that this happens.
rmcdaniels
03-13-2006, 01:04 AM
RLZ got a web site?
Not much of one, and they usually don't answer their phone or respond to e-mails, but they are usually pretty swamped with work.
http://www.hondaraceengines.com/
+1 on that info Roger. Thanks. :)
HONDA GHANDI
03-13-2006, 09:00 AM
The Exhaust side should be polished and the intake side should be rough to cause more turbulence. Nice head R. What cams did you decide to go with finally?
rmcdaniels
03-13-2006, 09:06 AM
Crower 63401T-2
Duration @ .050:
Int- 233
Exh-235
Lift:
Int- 466
Exh-445
HONDA GHANDI
03-13-2006, 09:11 AM
Low overlap numbers I assume?
rmcdaniels
03-13-2006, 09:21 AM
Pretty low, the intake has less duration than a GSR cam and the exhaust has slightly more than a CTR. I actually make more boost with these than with the GSR cams. I'll adjust them a bit on the dyno after I get the new header on it and see what comes out of it. I took a spin in it last night after I got it all bolted together and we did some street tuning, but I think I've got some air trapped in the intercooler. The charge temps were really hot (160) and the manifold was hot to the touch (normally it's cool to the touch, even after a dyno run). The manifold is the highest point in the system, so it's a bitch to bleed it. I need to do a bit more work on my lines and reservoir and fix that design.
saabracr
03-13-2006, 01:22 PM
How many times have you taken your engine apart and put it back together?
rmcdaniels
03-13-2006, 03:53 PM
How many times have you taken your engine apart and put it back together?
I don't know any more, but it's quite a few. I did the same thing with my Austin Healy, Camaro, etc. I just like to take stuff apart and mess with it, although hopefully the latest setup will be reliable and I can enjoy driving it for a bit.
rmcdaniels
03-13-2006, 08:41 PM
I put 100 miles on it today and did compression and leakdown tests. It's healthy again, 260-270 PSI and 1-3% leakdown.
Redteg
03-13-2006, 09:17 PM
Glad to hear its running again! Time for some vids...
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