Reply With QuoteBoat looks great man, keep us posted how motor performs!
BTW- how does the exhaust outflow the intake at .100 lift?
One thing to remember about the Canfirelds is that at low lift, with too agressive a ramp on your cam, you can suck the incoming intake charge right out the exhaust port. :notam:
Boat looks great man, keep us posted how motor performs!
BTW- how does the exhaust outflow the intake at .100 lift?
Boat looks great man, keep us posted how motor performs!
BTW- how does the exhaust outflow the intake at .100 lift?
Thank you for the compliment. Chamber shape and valve job.
Looking at the chamber photos I can't tell if your valve grind is a 3 or 5 angle grind.
Hey Jack...it's actually a four...I think the top is 28, then 45, then 60, and then just a bump on the bottom of the 60 with a 70. These really aren't killer heads, just decent. On a motor like yours, there is good power to be gained from such details. On this one, I'm just keepin it simple, and reliable. Notice the exhaust are just radiused with a 45, adn I think a 30 top. :coffeycup
Understood ... I was just curious. Everything looks good by the way ... Keep up the good work.
Canfield makes a good cylinder head... very nice right out of the box and very price friendly... even the larger head is a good deal. You spent your money well...imo.
Actually... I've been running them on my 489 for a few years and they work very well. The only thing I had a problem with was out of the 3 sets I bought at the time... all of them had seats with air pockets in them... and crack and fall they did in the first set... (bummer of a lake day) and changed out the seats in the other two sets before they made it out in the world. With anything new and performance... you don't want to be the first kid on the block with the new goodies because you get to find any problems that were not caught at the factory.
Scott,
You need to rough that intake port up with some 40grit cartridges. Won't show anything on the bench, shows nice "things" on the dyno.
PM me on the chambers and I will tell you what to do there. It pays when you are friends with the guy that designed that head.
Scott,
You need to rough that intake port up with some 40grit cartridges. Won't show anything on the bench, shows nice "things" on the dyno.
PM me on the chambers and I will tell you what to do there. It pays when you are friends with the guy that designed that head.
Chris, the intakes don't show it, but they're done with a 40g. I'd be interested to hear what to do different with the chambers, though.
Thanks for the advice. You'll be hearin from me.
Here's the results from the flow bench. A little disappointing on the intake...they fell a little short of Canfield's claims of 355 at .800. The exhaust were real strong, responding very well to the work I did, out performing Canfields numbers considerably, (excepet their .100 number)although they were slightly turbulent in the middle. The valve job and chamber/bowl work here made most of the difference, since I didn't change the shape of the port at all. The one difference on the intake's big numbers may have come from cyl. size when testing. Mine were flowed on a 4.31 fixture (my bore size) and Canfield may have flowed theirs on a 4.500 bore, allowing for a little more unshrouding. The stronger low to mid-lift intake numbers I came up with are, again, from good valve job and the work in the bowls and chambers, although I expected to step up the big number a little, as well. Nothing I did to the intake should have hurt the big end flow, so there's a little discrepancy here. I didn't change the shape of the port at all, just a little blending and opening match. Not much discrepancy, though. Less than 3%.
These are Canfield's numbers.
VALVE LIFT .100 .200 .300 .400 .500 .600 .700 .800
Intake Port 72 138 204 266 318 347 353 355
Exhaust Port 74 123 176 205 237 260 273
Here's my flow sheet:
http://www2.***boat.com/image_center...4/1729scan.jpg
Here's a side by side comparison using my average left-right numbers.
lift Can# My#
.100 72 74
.200 138 166
.300 204 243
.400 266 289
.500 318 320
.600 347 335
.700 353 341
.800 355 343
ex
.100 72 66
.200 123 135
.300 176 179
.400 205 216
.500 237 251
.600 260 279
.700 273 298
.800 --- 312
Most advertised flow numbers reflect the average between the right and left hand ports on a BB Chev. All in all I'm not disappointed. For a 310cc port the numbers are plenty strong, and way good enough for a 467" motor turning 6500. There are also some power mods I was able to do that don't really reflect on the flow bench, but will show on the dyno. Remember, the flow bench is only a measureing device, and not the be-all and end-all of cyl head performance. Now I can get to the meat and potatoes of putting this motor back together.
Next...designing the cam.
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