Re: Cam for EFI in big block
[Re: DaytonaTurbo]
#2037124
03/23/16 01:38 PM
03/23/16 01:38 PM
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Joined: Jan 2003
Posts: 16,376
dogdays
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First of all, it's not that unusual for the inside of the manifold to be wet with gasoline in an MPFI engine. There's a lot more going on in there than we imagine. I have spent hours with carb cleaner getting the varnish off the inside of supposedly dry runners.
Second, you said, "This is a street car and only sees the strip during fun runs at car shows." This tells me you aren't all that interested in a big top end charge, so your 241 duration at 50 cam is way too big. Plus as mentioned above the overdrive transmission and 3.54 gear point to a smaller cam.
Third, if you can afford a hydraulic roller why wouldn't you go to that? You can get big lift with moderate duration. Now, everyone is going to pooh-pooh this suggestion, but I think you'd be really happy with a Hughes SER2226BL3-10. This is 222/226 duration at 0.050 and 0.514/0.520 lift. Your heads are already set up for this amount of lift although I am sure you'll have to change springs to control the heavier lifter.
This site is famous for advising cams on the basis of getting the last tenth in a drag race. So you are going to hear about a lot of bigger cams. Then, you are also going to hear the familiar chorus of having someone pick a custom cam for you, as if the camshaft manufacturers haven't spent dyno time and don't know what they're doing. There's nothing wrong with getting a custom camshaft but understand that the custom cam picker uses standard lobes from the grinder's lobe catalog. So the cam picker picks out one or two lobes and the Lobe Separation Angle and how much the cam is ground advanced or retarded.
R.
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Re: Cam for EFI in big block
[Re: DaytonaTurbo]
#2037141
03/23/16 02:09 PM
03/23/16 02:09 PM
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Joined: Jul 2007
Posts: 531 Virginia
JimG
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Were you happy with the performance and manners of the EFI'd .509 otherwise? A wider LSA cam should make the EFI happy and help with MPG, which I would expect is a factor with an OD trans and a 3.54 gear. Overall, the EFI tuning is not quite where the carb was yet. But with the carb, you could lug the engine down to 45 MPH in 5th gear (.64 OD), and while it was no powerhouse down there, it would pull smoothly. I'd have to think that a camshaft with a wider LSA would, at the very least, have the potential to match or slightly improve upon this characteristic.
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Re: Cam for EFI in big block
[Re: AndyF]
#2037148
03/23/16 02:14 PM
03/23/16 02:14 PM
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Joined: Jul 2007
Posts: 531 Virginia
JimG
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If it was my engine I'd probably run a Mopar .528 solid flat tappet since I know it works really well for that type of mild stroker engine Andy, what sort of idle vacuum would you expect from the .528 cam in a 493? And would you install it straight up? With the 509, it idles at a whopping 8 - 8.5 in hg. I'd like to see that improve just a bit. Thanks!
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Re: Cam for EFI in big block
[Re: dogdays]
#2037158
03/23/16 02:26 PM
03/23/16 02:26 PM
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Joined: Jul 2007
Posts: 531 Virginia
JimG
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First of all, it's not that unusual for the inside of the manifold to be wet with gasoline in an MPFI engine. There's a lot more going on in there than we imagine. I have spent hours with carb cleaner getting the varnish off the inside of supposedly dry runners. . . Third, if you can afford a hydraulic roller why wouldn't you go to that? You can get big lift with moderate duration. Now, everyone is going to pooh-pooh this suggestion, but I think you'd be really happy with a Hughes SER2226BL3-10. This is 222/226 duration at 0.050 and 0.514/0.520 lift. Your heads are already set up for this amount of lift although I am sure you'll have to change springs to control the heavier lifter.
. . I didn't realize that reversion would cause so much fuel way up to the TB. In one of the Mopar magazines' test mule '67 R/T, they swapped their .509 for a Comp solid roller with, as I recall, around .550 lift, and less duration and a wider LSA than the .509. They said it idled smoother and pulled more vacuum at idle than the .509, but was a rocket. I've read that our roller lifters (solid or hydraulic) suffer from roller bearing failure when subjected to prolonged periods of idling, and then there's the whole bronze distributor drive and the maintenance requirement on it. I read extensively on roller cams about 5 years ago, and this information might be outdated now. That's another reason I did nothing - the roller sounded great except for those drawbacks, which I consider major. The added cost of a roller is not really an obstacle for me if roller is indeed the best choice, but those two items were a deal breaker for me. Now that it's 2016, I'm willing to consider some sort of roller again.
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Re: Cam for EFI in big block
[Re: JimG]
#2037239
03/23/16 04:22 PM
03/23/16 04:22 PM
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Joined: Aug 2011
Posts: 2,871 Pattison Texas
CSK
master
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master
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Pattison Texas
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this works well, 248 @ .050 solid flat tappet
Last edited by csk; 03/23/16 04:23 PM.
1968 Charger COLD A/C Hilborn EFI 512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim 2020 T/A 392 Stock 11.79 @ 114.5
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Re: Cam for EFI in big block
[Re: JimG]
#2037245
03/23/16 04:34 PM
03/23/16 04:34 PM
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Joined: Feb 2003
Posts: 21,318 Manitoba, Canada
DaytonaTurbo
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Overall, the EFI tuning is not quite where the carb was yet. But with the carb, you could lug the engine down to 45 MPH in 5th gear (.64 OD), and while it was no powerhouse down there, it would pull smoothly. I'd have to think that a camshaft with a wider LSA would, at the very least, have the potential to match or slightly improve upon this characteristic.
So you're saying at lower RPM your carb was performing better than your EFI system is? If that is the case, I think you first need to determine why you are unable to meet or exceed the street manners of the carb. IMO cam selection is not the problem.
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Re: Cam for EFI in big block
[Re: JimG]
#2037290
03/23/16 05:49 PM
03/23/16 05:49 PM
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Joined: Jan 2003
Posts: 1,938 Sonora CA
Mopar_Rich
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BTW: I love the converted Jeep cam sensor :^)
Last edited by Mopar_Rich; 03/23/16 05:49 PM.
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Re: Cam for EFI in big block
[Re: JimG]
#2037291
03/23/16 05:49 PM
03/23/16 05:49 PM
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Joined: Jan 2003
Posts: 31,060 Oregon
AndyF
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I Win
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If it was my engine I'd probably run a Mopar .528 solid flat tappet since I know it works really well for that type of mild stroker engine Andy, what sort of idle vacuum would you expect from the .528 cam in a 493? And would you install it straight up? With the 509, it idles at a whopping 8 - 8.5 in hg. I'd like to see that improve just a bit. Thanks! Here is a cam article I wrote a few years back. Any of these cams would work fairly well in your engine. I think I have a few of these cams still sitting on the shelf. The Racer Brown cam for sure and maybe the Comp. http://www.moparts.org/Tech/Archive/bb/Lobe.html
Last edited by AndyF; 03/23/16 05:50 PM.
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Re: Cam for EFI in big block
[Re: DaytonaTurbo]
#2037477
03/23/16 11:00 PM
03/23/16 11:00 PM
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Joined: Jul 2007
Posts: 531 Virginia
JimG
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So you're saying at lower RPM your carb was performing better than your EFI system is? If that is the case, I think you first need to determine why you are unable to meet or exceed the street manners of the carb. IMO cam selection is not the problem.
Agreed. I just haven't spent much time tuning yet and I wondered if, since the existing cam was less than ideal, if I'd be better served to change it to something more EFI friendly before spending time trying to tune what I had.
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Re: Cam for EFI in big block
[Re: Mopar_Rich]
#2037887
03/24/16 04:53 PM
03/24/16 04:53 PM
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Joined: Jul 2007
Posts: 531 Virginia
JimG
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I now know this is an MS installation. Heads up if you're thinking about buying a FAST package... I gotta give big props to Mopar Rich. He thought I had a FAST installation and, without me asking, sent me a long PM with all sorts of advice and offers of help. I told him it was a Megasquirt installation and he still replied with some camshaft advice. Based on this, he gets "good guy" status in my book. Rich, you can change the injector end angle (one of the features that I have not yet mastered scratched the surface on) in MS... I'm still learning, but that's the fun.
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Re: Cam for EFI in big block
[Re: JimG]
#2038041
03/24/16 09:17 PM
03/24/16 09:17 PM
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Joined: Jan 2003
Posts: 1,482 Lake Orion, MI
goldduster318
pro stock
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pro stock
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Lake Orion, MI
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You don't have to go real small on the cam. I have a similar install, sequential mode efi, coil near plug on a 340 with a 227/231 duration at .050 hydraulic roller cam with 110 LSA and it loves it. I have never noticed any wetness in my intake manifold. Your 493 should be able to eat a lot more duration than my 346ci engine anyway. I haven't touched any of the injector trim angles but the car runs amazing even at low RPM ranges. I'd be curious on what your idle ignition advance is. My car pulls about 13.5 in Hg at idle (900rpm) and has 22 degrees advance at idle. For tuning in general, do some light driving with the self-learn feature on and then start datalogging when the engine is warm and use the megalogviewer and the VE analyze feature. The more time you spend in the RPM ranges, the better the tune will get on your VE table. Even if I don't get too many hits in an area - I try to smooth it out. So far, it has worked well. In my case, so much better than the carb after only a few hours of driving.
'70 Duster 470hp 340/T56 Magnum/8 3/4 3.23 Sure-Grip
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