Guest zfan Posted August 14, 2005 Share Posted August 14, 2005 A friend offered me 700-800 bucks for my Canfield heads. They are the 200cc runner size with 2.055/1.60 valves and minor port work. They are currently mounted on my 385 sbc. I am going to have to tear it down next week due to a blown head gasket. My question is it worth it to sell the heads and buy a set of Canfield 215's or AFR 210's. Would I even make much more power or am I just wasting my time? I am also going to do some cam work as well. I see solid roller cams in my future. Not that Hydraulic rollers are bad it is just that there are not many around. Mike Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted August 14, 2005 Share Posted August 14, 2005 I don't think any of the newer heads are going to make alot of additional power over what you have and with a price tag of $1300 for AFR's and getting $800 for yours that it would be worth the extra $500 to get a couple more ponies, if that. IMO i'd stick with what you have unless you were going to go roller and move the rpm's up to the high end, then I'd ditch those and get some AFR 220's or 227's or similar, but then that'd be race only pretty much. Quote Link to comment Share on other sites More sharing options...
Guest the_dj Posted August 18, 2005 Share Posted August 18, 2005 Valve & runner size alone doesn't say much about how they perform. I had 2 sets of ported heads (by two different companies). Both had 2.02 intake and 1.55 exhaust valves. Both had the same runner size. Both were GM LS1 heads. The first had swirl polished gorgeous valves and looked like a better porting job. It flowed 272 on the intake. The other had charred looked "meh" valves. I wasn't expecting so much from it, but it turned out to flow a consistent 300cfm on the intake. Harold at Port Pros (excellent work, local) said it would cost $400+ to make the first set flow as well as the second. Moral of the story is get your flow numbers because visuals don't mean jack. Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted August 18, 2005 Share Posted August 18, 2005 He's right, that's why all the tests show that non altered aftermarket heads flow good, but AFR's stand above them all. Canfields are just right there, just an earlier version. It's the engine package that makes it work, not peak or average flow numbers. Cam's gotta match the heads, intake, carb, exhaust, compression, it all works together. If you talking ported aftermarket heads or ported stock heads then it's a different kettle of fish, then your looking at some $$$$. Call AFR and check on CNC race porting, well over $3K just for porting above the CNC race version heads. If your going to solid roller then you have to get upgraded valves, retainers, springs and possibly have the guides and seats done, so then it's a no brainer, sell what you got and get some that are ready to go out the door. The performance of a solid roller is what will impress you. If you think valves are all the same, they are not, different alloys and the high spring pressures will pull the tops off the valves, seen it happen recently in a BBC. Guy put roller springs and retainers on the bottom of the line manley street stainless valves to save some $$$, 3 passes and it sucked a valve, destroyed the block and one head. Post mortem last week and the top of the valve was still in the retainer with keepers, pulled apart like it was drawn just below the keeper, much reduced crossectional area where the failure occurred. Quote Link to comment Share on other sites More sharing options...
John Scott Posted August 19, 2005 Share Posted August 19, 2005 AFR has a package for solid roller cams. Give their tech line a call with cam specs. They set me up with 7/16ths studs, valves, and the bigger 1.550 springs good for mid .600 lift. You also might want to visit Prestage.com and see how the dedicated drag racers are using small port heads and turning big numbers. As Dr_Hunt stated its more the combination of well matched parts. I dumped a set of larger port Pro 1s, 300+ cfm, for the AFR 195s, because for my 383 they didn't have the low speed velocity, didn't pull until 4000, and wanted more cam than I would personally like on the street. The Pro1s would have been great for 1/4 mile only duty. John Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted August 19, 2005 Share Posted August 19, 2005 John, What camshaft are you using in your 383 combo. I am running a hydraulic roller cam duration is 236/242,Intake lift is 553 with 1.60's and exhaust is 540 with 1.50's. I have been entertaining swapping to a solid roller cam. With this Comp cam in straight up with 4 degrees built in to it my cylinder pressure is to high for the street and 93 octane. When last checked I was making 210-220 cold cranking cylinder pressure. I can retard the cam 4 degrees and drop probably 10 psi off and thats a start. I think 11 to 1 compression probably was pushing the envelope to hard. Mike Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted August 19, 2005 Share Posted August 19, 2005 Yeah, with 11:1 you'll need alot of cam to bleed off that cylinder pressure. I think HotRod did an article on a street motor with 11:1, ran alum heads and a solid roller with about 250 or 260 duration at .050 all on 93 octane pump gas. At least back then you could afford pump gas. When I was in HS I was buying avgas for $2/gallon. You might think of getting larger combustion chambers, say 76 cc, that might help unless your getting that kind of compression with 70cc heads or so. What are you running anyway? Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted August 20, 2005 Share Posted August 20, 2005 Canfield 200cc heads, they have 65cc combustion chambers. I wish they were like 70cc or bigger. Would solve alot of problems. Mike Quote Link to comment Share on other sites More sharing options...
John Scott Posted August 20, 2005 Share Posted August 20, 2005 John' date=' What camshaft are you using in your 383 combo. Mike[/quote'] All the major cam company tech guys can help out alot when you give them all your car specs. It would be best to taylor your cam exactly to your engine components, driving style. My Isky part # 201575 Grind # RR575. I think it was a small base circle for the stroker, and had cast distributor gear for street durability. Lobe lift: .384 on intake and exhaust, 244 duration @ .050, 108 lobe center. I guess my memory was a little off in the lift with CC Pro mags 1.52 and 1.6 ex rockers. .583/614, as AFR recomended the split pattern for this head. Isky and my engine builder, like the tight lobe center for a compact powerband. I would have prefered a 110 for a more spread out powerband, but it comes on really hard, quick, and strong through the mid upper range. Peak torque as I recall is around 4400, peak Hp around 5600. Good since the 383s typically make their power at lower rpms than 377s etc. It still pulls hard to high 6K and will hit the 7K limiter in a blink when traction is lost. Whats nice about the strokers in the light weight Z is the flat torque curve. I can cruise without surging, bucking problems at slightly below 2000, but little power. Our Octane is a piddly 91, but near 5000 feet altitude. Timing around 18 initial, 36- 38 total. Good aluminum chamber design, light car, and this cam's duration lsa allow me to run 11:1 with the AFR 68 cc head. SRP forged pistons are just in case. Also, don't forget to check those push rod lengths! I ended up with slightly oversize. Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted August 20, 2005 Share Posted August 20, 2005 Well if you went to something like AFR's, they have 76CC chambers, that would drop you into pump gas range real quick. Quote Link to comment Share on other sites More sharing options...
John Scott Posted August 20, 2005 Share Posted August 20, 2005 Well if you went to something like AFR's, they have 76CC chambers, that would drop you into pump gas range real quick. Good advice since most are going to build an engine following the latest Hot Rod article or off the shelf parts without any experience or research. A 74 cc AFR will drop your 383 approx. 11.0 to a "safe" 10.25, which of course will work best with smaller cam. I'm amazed how many start with a cam and try to build an engine around it. Heads, flow, compression should pick the cam.The mag articles won't put you on the edge, but usually well into the safe zone. I didn't have the expertise, so I let a reputable experienced race engine builder handle the details with ocassional input. No race gas or timing changes for race day was one of my stipulations. You will be on the edge, but this will work was all I needed to hear. Its nice to see your engine builder regularly at the track on race day standing behind his product. John Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted August 20, 2005 Share Posted August 20, 2005 My engine builder is multi purpose, builds engines, transmissions, rear ends, fabs cages and then tows the car to the track and drives, even pays for entry. He's ok in my book. The AFR210's might be a good choice also, they have 76 cc chambers and are good from 3K up in a 350 to 400. My little 350 has AFR220's and it works great on the street. Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted August 21, 2005 Share Posted August 21, 2005 I currently run the car on 93 octane with the total timing set at 32-33 degrees and have no detonation problems. Knock on wood! I am seriously just considering retarding the cam back 4 degrees and running it or atleast see how it behaves and check cylinder pressure. I have a few idea's on cams and talked to Grumpy at length about what might be a good cam to try out if need be. Also talked to Crane, Crower and Comp about cams as well. I think for now I will stick with my heads unless I want to go high lift cam then it would make sense to look at new heads as the Canfield 200's do not really flow well above 550 lift, at that point the are flowing no more air at 600 lift. The bigger canfields or AFR's really take over from there. With the cam in 4 degrees advanced it made 360 hp and 400 ft. lbs of torque. Not too bad considering the 700r4 tranny is a complete horsepower eating pig! Mike Quote Link to comment Share on other sites More sharing options...
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