jt1 Posted July 25, 2005 Share Posted July 25, 2005 While my motor is apart, I decided to have the heads flowed. I bought these as bare castings and had them assembled by a local machinest. Canfield listed flow #'s on their website with a "mild bowl blend", so before assembly, I smoothed out all the machining ridges where the seats were installed, blended machined areas to the cast areas, streamlined the valve guide boss, and smoothed up rough areas and parting lines in the castings. I probably put about 6 or 7 hours work in the heads myself. I was curious if the heads flowed the advertised #'s, and if my backyard bowl job was reasonable. I've heard some of the 5.0 ford crowd say the canfields weren't anywhere close to the advertised #'s, and wanted to see for myself. SF 600, 28", radius inlet on intake, 4" cylinder fixture, 1 3/4" pipe 30" long on the exhaust, 2.05 & 1.60 Ferrea valves. Here we go: Intake Lift Adv Actual 200 145 145 300 201 197 400 247 245 500 258 255 600 259 259 Exhaust Lift Adv Actual 200 107 110 300 143 143 400 175 169 500 190 185 600 200 196 I was pretty pleased, the actual #'s are very close to the advertised ones, and apparently my home bowl blend didn't screw anything up. These variations are well within what could be expected between different benches and minor differences for the valves, valve job, etc. This guy also has a Superflow SF901 dyno, so I'm going to get her put together and take her to the water pump in a couple of weeks. More to come...... John Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted July 25, 2005 Share Posted July 25, 2005 congrats on getting a reasonable result from your flow testing, BTW minor bowl cleanups done correctly almost always result in better not worse flow numbers, so taking the time is well worth the effort Quote Link to comment Share on other sites More sharing options...
Guest coolmesser Posted July 25, 2005 Share Posted July 25, 2005 wish I could afford such heads. sweet. Quote Link to comment Share on other sites More sharing options...
pparaska Posted July 27, 2005 Share Posted July 27, 2005 Nice! Low/mid lift flow is up there with the similar AFR 190/195's. I also had similar good experience with flow testing Canfields. The exhaust didn't turn out so well out of the box (but the intakes were BETTER than advertised), but a minor cleanup on the exhaust bowl area fixed that: http://alteredz.com/data/canf215flow_1_data.htm Can't wait to see how your engine goes on the water pump - Have any computer simulations to compare that to? DD2000?, etc.? Quote Link to comment Share on other sites More sharing options...
jt1 Posted July 27, 2005 Author Share Posted July 27, 2005 Those 215's rock, Pete. A little work really picked up that exhaust. These heads are within +/- a few cfm of the AFR 195's, except at 400 on the exhaust, where these are about 10 cfm short. By 500 the Canfields have caught back up. It would be interesting to know what goes on there. I don't have any of the simulation programs. If somebody does and wants to plug in the data, I'll supply all the specs. John Quote Link to comment Share on other sites More sharing options...
jt1 Posted August 19, 2005 Author Share Posted August 19, 2005 I took the motor to the dyno yesterday. Despite good intentions, high hopes, etc., it was a disappointing day. I arrived at 1 pm for a 5 hr scheduled test. The shop can't run the dyno past 7pm because of noise & neighbors. I had my motor with the performer rpm air gap and 700 dp, plus a victor jr. and a borrowed 830 annular. We spent about an hr getting the motor setup on the dyno, exhaust hooked up, ignition, water, etc. Set the timing, let it warm up, and started a baseline pull from 2500 to 7000. Things started going wrong immediately. For some reason, the dyno wouldn't load the motor at low rpm. It would kick in, release, jack the throttle around, repeat, and produce data points that looked like a shotgun pattern (improved cylinder at best). They had a huge thunderstorm Wednesday and got a lightning pop that fried a bunch of other stuff in the shop, and it appeared it got the dyno. The operator thought it was the rpm pickup, so we changed that. No help. Then we changed the ring on the driveshaft, still no help. Spent about 30 min on the phone with superflow, messing with the computer, same results. Dammit. By now it's almost 3pm. Still trying, we found if we started the pull at 4K, things went well, but the AF meter wasn't working. New O2 meter, no help, ghetto rigged a voltmeter to the O2 meter to get some idea of AF, but no way to plot or relate to rpm. Proceeded anyway, damn the torpedoes. 1st pull, air gap, 700, jetted 66/71: trq 402 @ 4K, peak 420 @ 5100, holding 400 to 5800, hp peak 461 @ 6200. AF bouncing in the 13's, BSFC mid 3's, so we fatten it to 68/73 2nd pull: trq 418 @ 4K, peak 429 @ 5400, holding 400 to 6200, peak hp 481 @ 6700 AF in the 12's, occasional 13's, BSFC about .37-.38. By now it's after 5pm, I know there's no way to get done everything I wanted. The 700 probably needs a little more jet, but times wasting, so we put the 830 on, jetted 84 square. 3rd pull: trq 420 @ 4k, peak 446@ 5300, holding 400 to 6500, peak hp 495 @ 6600 AF 12-13, BSFC .37-.38. We put 86's in the 830. 4th pull: trq 428 @ 4K, peak 449 @ 5600, holding 400 to 6500, hp peak 499 @ 6700 AF still 12-13, BSFC .38-.39, so we put in 87's. 5th pull: trq 424 @ 4K, peak 448 @ 5100, 400 to 6500, hp peak 502 @ 6400 AF mostly 12's, BSFC .39-.40 It's past 6pm and it looks like that's about all the jet the carb wants. Plugs are beginning to show a little more fuel ring than we'd like. We change timing from 36 to 33, since sometimes pump gas motors don't like as much timing. Bad idea. 6th pull: trq 368 @ 4k, peak 446 @ 5600, 400 to 6400, hp peak 497 @ 6200 The upper #'s aren't bad, but loosing 56 ft-# at 4K isn't what you want for a road race engine. We decide to try 38 deg. 7th pull: Basically a duplicate of #5, maybe 1 or 2 numbers different here and there, but not enough to be significant. 36 looks good. We reset the timing, it's now 6:45, and try another pull from 2500-7000. Same results as before, dyno loads/unloads and fires another shotgun blast graph. We let the motor cool down to 140 deg and shut it down at 7pm. We get the motor unhooked, everything loaded up, I get back to my shop, unload, and get home at 11pm. I'm exhausted and somewhat bummed. General observations: I didn't even get to try the vic jr. It would have probably helped the top end some, but I was curious how much torque it would lose to the air gap. The 830 annular made good torque and hp. Next question is how much throttle response it will loose to the 700. Once the car sets, I pretty much steer with the throttle and sometimes even hang the rear out a little, so the TR is important. Only getting it on the track will tell that. The 830 is good up top, but obviously FAT HOG RICH at lower rpm, so I'm gonna need to work on that with my LM1. Not getting to see the rpm range I wanted was a major downer, because I run the motor from about 3K to 7K at the track. Everytime I don't have to shift is saving an opportunity for me to screw up. I wanted to see the torque #'s at lower rpm, esp. between the two carbs. Supposedly the annulars are best at lower rpm. No good AF #'s was the worst. We basically tuned the carbs like in the pre O2 meter days. At 500 rpm/sec, a 3K - 7K pull only takes 6 seconds, and the flashes of the digital voltmeter went by very quickly. I can't believe I was stupid enough to leave the LM1 laying at the shop. The best thing was the motor performed flawlessly, and made a little better #'s then I anticipated. I'm gonna cut open the oil filter, run the valves and inspect the valve gear closely. I was gonna run the valves on the dyno after the first pull, but since time was short I skipped that. I'm gonna forget the dyno, get the motor in the car and take it to the track in Sept. Sorry for the long read. I'd really like to hear any comments, observations, and suggestions. John Quote Link to comment Share on other sites More sharing options...
MONGO510 Posted August 19, 2005 Share Posted August 19, 2005 Since the dyno was still acting up when in use I would not really trust any #'s out of it. I hope you got a huge discount on the dyno time. John Quote Link to comment Share on other sites More sharing options...
Mikelly Posted August 20, 2005 Share Posted August 20, 2005 John, that's still an impressive test. Shame the machine wasn't cooperating. Refresh my memory, but is this a 383, 377 or 350/355? Have you contemplated a swap to FI? Mike Quote Link to comment Share on other sites More sharing options...
jt1 Posted August 20, 2005 Author Share Posted August 20, 2005 Mongo- I agree the whole show is somewhat suspect, one reason I was pretty bummed about it. The dyno guy was of the opinion the numbers we were getting were good, just that we couldn't get them where we wanted. He was extremely sorry we had trouble, and said he wouldn't charge me anything if I would agree to come back for another 5 hr session. ($250) Since I want to go ahead and get the car ready for the track, we agreed on $100. I was happy with that. Mike- It's a 355, 10.3:1 comp, pump gas motor. I've though about EFI a lot, just like I think about the LS motors, but haven't made the leap yet. I figure I'm about 20 yrs behind current technology. John Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted August 21, 2005 Share Posted August 21, 2005 If those numbers are near correct they are pretty good for a 355 chevy, nothing to sneeze at. Good luck with your next dyno/tuning session. I have had problems on the chassis dyno with running a 3500 stall converter, it can go all over the place and gets really frustrating . Guys running dyno say it happen frequently when you have a higher stall converter. Results can be all over the place. Mike Quote Link to comment Share on other sites More sharing options...
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