prairiehotrodder wrote: ↑Fri Jul 30, 2021 3:53 pm
This motor is getting some AFR 245 heads along with 1 7/8 headers and a holley strip dominator intake. Hopefully get to the track Aug 20.
Brian
Brian,
are you going to get the heads and intake manifold rubbed ''ON''?
i understand there is more expense but we want to make more power
how about redoing the heads you have now
By the time we port these heads we might as well buy the 245's and sell the 227's. We will just stick them on and run em. See what happens. Something has gotta be the cork in this motor. Just swapping these heads is way quicker than sending them away for porting. Maybe dyno time will be in the program this winter if the world doesn't end.
Brian
1. I'm going to rule out headers as the problem.... Simply because we have had several 380-390 inch engines with 1 3/4 primaries and 3 inch collectors that have had no issues at all running 141 to 143 miles per hour at high 9.40s at 2800-2850 lbs at 8000-8250 finish line rpm. I don't believe a 420 inch engine is moving any more air at 7400 RPM then a 390 inch engine at 8200. Would a bigger header help? Maybe a tenth or a tick over. Is it the answer this time? I doubt it.
2. I'm going to rule out the cylinder heads just because I've seen ported Chevy vortec factory iron castings have no issue going low tens at 3000 lbs...... And even though I don't care a whole lot for AFR heads, I refuse to believe so they can't make a 227 runner head that cant stomp a ported factory casting without issue..... Even if the speed is off. Is there a lot to be found in the heads? I'm sure there is. Ultimately there might be 50 to 75 horsepower in the heads alone. With the work done I'm sure 700+ is doable power. Just not as they came from AFR. Is it the issue? I doubt it.
3. The manifold is not the issue. I'm sure it has no problem hanging with a warmed up Holley Strip dominator which is what we've been using on the smaller inch engines that are going 140+.
4. I doubt the camshaft is causing much issue even if it is a tick on the large side. Could it benefit from a little less duration and a lot more lift? Probably. Maybe 15 or 20 horsepower to be found I'd guess. I put up a post in 2005 or 2006 about a 421 on the dyno with similar compression, ported dart conquest heads, and an even bigger cam.....low 280s, low 290s. And it still made over 600 horsepower with the mismatched camshaft. It peaked at a disgusting 6200-6300 if I remember right. But 600 horsepower is still 600 horsepower. I'm sure the cam isn't the major culprit.
5. The converter isn't the real issue in my opinion (unless it's hurt). It might need a tick more flash, but at least it's in the ballpark.
6. I'm going to go out on a limb...... And say look into the transmission for a problem. The same 421 that I mentioned up above that made 600....... Ran a nasty two month long string of low 11s at 118-119 mph in a 3470 lb race weight Malibu back in 2005. The timeslip incrementals all matched perfectly to a typical low 11 pass. 1.52 sixty foot and all. We constantly thought the engine was down on power. Were we happy with the 600 horsepower that it ended up making? Not really. But was it the reason the car was slow? Nope. We ended up pulling the transmission, something inside it was in a bind or broken. I don't remember what the transmission guy said....... But I can tell you the day that it went back in, the air was hot..... The DA was near 4200, and the first pass off the trailer went high 10.30s at 129.9, with a 1.41 sixty foot. Once again, all the timeslip incrementals made sense. Problem solved.
Thanks for the suggestions. In your tranny experience did it get real hot ? Was the fluid burnt ? If something was binding i'd expect the second half of the quarter to be much worse. This car has a turbo 350, what did you have ? I'll look into it.
Brian
prairiehotrodder wrote: ↑Fri Aug 06, 2021 11:01 am
Thanks for the suggestions. In your tranny experience did it get real hot ? Was the fluid burnt ? If something was binding i'd expect the second half of the quarter to be much worse. This car has a turbo 350, what did you have ? I'll look into it.
Brian
We had no idea it was the trans at all. It have no indication. And it WAS a th350
prairiehotrodder wrote: ↑Fri Jul 30, 2021 3:53 pm
This motor is getting some AFR 245 heads along with 1 7/8 headers and a holley strip dominator intake. Hopefully get to the track Aug 20.
Brian
I hope it's the 300-110 as I cannot see the 300-25 making much difference on the 245's over that Titan intake. As for the header deal, I was able to run high tens last year with some el-cheapo 1 5/8" headers and when I switched to the bigger S/C Hookers I picked up nothing. I most of the time use a pair of Walker bullets on my car (no open exhaust early at our track) and when I take them off the car slows down as I have tuned it that way. I would put the new Eddy SV II on that 423 SBC myself. That car should be a 10.0 car all day.
So am i correct that going to a bigger head will "slow down" the incoming mixture ? So if the old heads were to fast, going to a bigger head will help to correct the situation ? I am also losing some compression. The 227's had a 65 cc chamber, now i have a 70 cc chamber. I think i was at about 13.3 before. Now i will be at 12.5. That may offset all my gains from flow ?
Brian
Brain , sometimes its not the cc size and or velocity but the shape of the port. Check out Eric Weingartner's (hope I spelled that correct ) you tube videos . he has a few on AFR 227's and 245's talks about the good and the bad of each . All I can say is somethings not right with that combo . My 422 with Dart 220 race series heads that I just poured at 223cc after some throat and pinch work along with 1.5 pts less compression, 14 degree less cam duration both intake / exhaust and a 200 cfm smaller carb and 150 lbs. more weight. ran a 6.31 1/8th in good air and 6.41's all summer long in bad air when I was in south west La. racing in southeast Texas . Did y'all get the jetting right if I remember correct , last year y'all were dealing with being way rich. Not bragging my combo because there's a lot that could be better just giving something to compare . Good luck Dan
So this car is going down the track this weekend God willing. I know i'm only supposed to do one change at a time but we don't have time for that. Here is a list of mods since last time at the track :
tubbed the car with a CE 4 link kit and 14 x 32 ET drags. Same 4.56 gears
AFR 245 heads
Holley Strip dominator intake
Hedman husler 1 7/8 headers with 3.5" collectors and a couple feet of pipe but no mufflers.
cast aluminum deep trans pan and higher flow filter.
lightweight fiberglass trunklid
gotta get this car weighed. I feel like i have no clue whats gonna happen at the track. Will be interesting. Also will be paying close attention to the AFR and making adjustments as needed.
Brian
Doesn’t sound like that’s enough gear for 32” tires and the speeds you’re running.
But...... good luck!!
Hope you see some gains.
The way I look at it, the big tires are a step in the wrong direction for what the car runs now....... so if the car ET’s the same as it did before, I would call that a net gain overall.
prairiehotrodder wrote: ↑Sun Aug 16, 2020 7:49 pm
I've posted about this motor before. I've been coaching a friend on this motor and i think i might get fired pretty soon because i can't figure it out. It has me looking like a fool. Its got all top notch parts and won't perform. Tell me what you think :
423 SBC 3.875 stroke x 4.165 bore dart little m block , callies crank, JE pistons (short block from steve schmidt race engines)
13 - 1 CR runs on AV gas, also tried C12 makes no difference
AFR 227 fully CNC heads with T&D shaft rockers
AFR titan plastic intake 4150 flange single plane with 1" spacer on top
QFT 1050 carb (4150 flange)
comp custom solid roller 274 / 282 @ .050 .660 lift 110 LSA installed 4 advanced.
1.75 hooker super comp headers for a G-body
3" exhaust with flowmaster super 40 mufflers.
holley 150 fuel pump / 1/2 " fuel line
78 pontiac Lemans 4.56 gear, turbo 350 / 5500 stall
around 3000 pounds race ready
As other have said:
wrong cam, get the flowmasters off of it, will probably need more fuel pump, and may need a different carb. probably needs a custom converter too.
"Anyone who thinks the low RPM engine will be faster just does not have as much experience as the rest of us" -The late, great Joe Sherman.
You wont beat anyone if you do everything the same as everyone.
the flowmasters are gone, the fuel pump has a pressure gage and never lost pressure in fact the carb has always been to rich. I'm not blaming the cam. So all in all i feel i could blame the carb and it may eventually get the boot. Depends how this weekend goes. Convertor was not slipping or showing any problems though it may want a higher stall speed but i doubt that is the source of our problems. I'm fully willing to tell the truth if i screwed up on this combo.
Brian
rewguy wrote: ↑Fri Aug 06, 2021 3:30 am
I'm going to take a new approach to this.
1. I'm going to rule out headers as the problem.... Simply because we have had several 380-390 inch engines with 1 3/4 primaries and 3 inch collectors that have had no issues at all running 141 to 143 miles per hour at high 9.40s at 2800-2850 lbs at 8000-8250 finish line rpm. I don't believe a 420 inch engine is moving any more air at 7400 RPM then a 390 inch engine at 8200. Would a bigger header help? Maybe a tenth or a tick over. Is it the answer this time? I doubt it.
2. I'm going to rule out the cylinder heads just because I've seen ported Chevy vortec factory iron castings have no issue going low tens at 3000 lbs...... And even though I don't care a whole lot for AFR heads, I refuse to believe so they can't make a 227 runner head that cant stomp a ported factory casting without issue..... Even if the speed is off. Is there a lot to be found in the heads? I'm sure there is. Ultimately there might be 50 to 75 horsepower in the heads alone. With the work done I'm sure 700+ is doable power. Just not as they came from AFR. Is it the issue? I doubt it.
3. The manifold is not the issue. I'm sure it has no problem hanging with a warmed up Holley Strip dominator which is what we've been using on the smaller inch engines that are going 140+.
4. I doubt the camshaft is causing much issue even if it is a tick on the large side. Could it benefit from a little less duration and a lot more lift? Probably. Maybe 15 or 20 horsepower to be found I'd guess. I put up a post in 2005 or 2006 about a 421 on the dyno with similar compression, ported dart conquest heads, and an even bigger cam.....low 280s, low 290s. And it still made over 600 horsepower with the mismatched camshaft. It peaked at a disgusting 6200-6300 if I remember right. But 600 horsepower is still 600 horsepower. I'm sure the cam isn't the major culprit.
5. The converter isn't the real issue in my opinion (unless it's hurt). It might need a tick more flash, but at least it's in the ballpark.
6. I'm going to go out on a limb...... And say look into the transmission for a problem. The same 421 that I mentioned up above that made 600....... Ran a nasty two month long string of low 11s at 118-119 mph in a 3470 lb race weight Malibu back in 2005. The timeslip incrementals all matched perfectly to a typical low 11 pass. 1.52 sixty foot and all. We constantly thought the engine was down on power. Were we happy with the 600 horsepower that it ended up making? Not really. But was it the reason the car was slow? Nope. We ended up pulling the transmission, something inside it was in a bind or broken. I don't remember what the transmission guy said....... But I can tell you the day that it went back in, the air was hot..... The DA was near 4200, and the first pass off the trailer went high 10.30s at 129.9, with a 1.41 sixty foot. Once again, all the timeslip incrementals made sense. Problem solved.
I'd sure be interested to know what was wrong in that transmission.
prairiehotrodder wrote: ↑Wed Aug 18, 2021 1:59 pm
the flowmasters are gone, the fuel pump has a pressure gage and never lost pressure in fact the carb has always been to rich. I'm not blaming the cam. So all in all i feel i could blame the carb and it may eventually get the boot. Depends how this weekend goes. Convertor was not slipping or showing any problems though it may want a higher stall speed but i doubt that is the source of our problems. I'm fully willing to tell the truth if i screwed up on this combo.
Brian
Ran my car last week with the 406 through the Flowmasters and without, not much difference. With the small 750 Holley it went from 10.95 to 10.79 open and there was only 1.5 mph difference.
