505 stroker LSA
#2635115
03/21/19 09:43 AM
03/21/19 09:43 AM
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Joined: Jan 2008
Posts: 35 Livonia,MI
1968fury
OP
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OP
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Livonia,MI
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I keep reading that stroker engines like a wider lobe separation angle. Can someone explain why. I'm building a 505 with 11:1 comp trick flow 270 heads and a Indy dual plane with max wedge ports and I'm trying to figure out what cam to use. I'm leaning towards this Hughes cam http://www.hughesengines.com/Index/...mxhdCBUYXBwZXQsIFNvbGlk&partid=30281But have it ground with a 110 or 112 LSA 3:91 gear and a 4 speed Thanks
71 scamp 340 509 cam 456 gear,68 fury1 318 3spd on the tree,50 merc flathead 3x2 3spd w/overdrive
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Re: 505 stroker LSA
[Re: 1968fury]
#2635131
03/21/19 10:27 AM
03/21/19 10:27 AM
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Joined: Jan 2003
Posts: 4,296 Chicago, IL
TonyS451
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Chicago, IL
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I keep reading that stroker engines like a wider lobe separation angle. Can someone explain why. I'm building a 505 with 11:1 comp trick flow 270 heads and a Indy dual plane with max wedge ports and I'm trying to figure out what cam to use. I'm leaning towards this Hughes cam http://www.hughesengines.com/Index/...mxhdCBUYXBwZXQsIFNvbGlk&partid=30281But have it ground with a 110 or 112 LSA 3:91 gear and a 4 speed Thanks Get in touch with fast68plymouth . He is a Comp cam dealer and Mopar engine specialist, and can get you a custom cam to match your combo and needs to a T.
2 kids and a dog
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Re: 505 stroker LSA
[Re: 1968fury]
#2635154
03/21/19 11:07 AM
03/21/19 11:07 AM
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Joined: Sep 2014
Posts: 4,457 Washington
madscientist
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Washington
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Cam grinders love to blow the LSA out to make the idle smoother, but it is a power loser in the worst place possible. Your mid range. They love to reduce intake duration, add exhaust and the open the LSA up to make the RPM hang on.
The LSA will take care of itself when you get the duration you need with the events correct. I can say this...at your displacement and your limited induction I'd say when everything else is correct about the widest LSA you'll see is 111 and I suspect it would be better in the middle (the gear changes and coming off the transbrake or even worse off the foot brake) if the timing was changed to a 109 LSA.
That's my humble .02 and it's not even worth what you paid for it.
BTW, if a cam grinder wants me to add exhaust duration or remove intake duration (I've never been able to nail a cam grinder down as to which they are doing except one and that was Kip from CamMotion and that was on alcohol and that's why he added exhaust duration) he needs to tell me why. If he can't, I move on and find another. Other than power adder stuff, or alcohol engines, I've never seen a correctly spec'd single pattern cam make less power.
Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
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Re: 505 stroker LSA
[Re: 1968fury]
#2635177
03/21/19 11:55 AM
03/21/19 11:55 AM
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Joined: Aug 2003
Posts: 43,157 Bend,OR USA
Cab_Burge
I Win
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I Win
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Posts: 43,157
Bend,OR USA
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I've been told and used the theory that spreading the LSA gives up bottom end power and increases the top end power, a tighter LSA will affect the manifold vacuum and idle quality and sounds I have pump gas stroker like yours on the engine stand that has a solid roller Crower that has 261@.050 on the intake lobes with .430 lobe lift and 263@.050 with the same lobe lift and it is ground on a 105 LSA, it has a set of ported 440-1 with a set of Harlnad Sharp 1.55 ratio rockers. I have ran it on a engine run stand and it idles very nicely I like bottom end power more than revving the heck(above 6000 RPM out of the motor to make power On your deal with the stick shift and 3.91 gears I would go with the 108 LSA and install it between 103 to 105 intake lobe center and plan on shifting it between 5500 RPM and 6300 RPM, where ever it quits pulling hard
Last edited by Cab_Burge; 03/21/19 11:56 AM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: 505 stroker LSA
[Re: Cab_Burge]
#2635196
03/21/19 12:20 PM
03/21/19 12:20 PM
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Joined: Jan 2003
Posts: 2,094 central texas
krautrock
top fuel
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top fuel
Joined: Jan 2003
Posts: 2,094
central texas
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with a 505...and huge amounts of low end torque, it seems a wider LSA would soften the bottom end just a tad and extend the rpm range up a bit. also, clean up the part throttle and idle some (if that matters)... but it all depends on so many things.
look at Andy's post about the 490 he built, the torque peak was at 4800rpm i think, with the PP240 heads and a pretty small cam...
so where do you want the torque peak?
Last edited by krautrock; 03/21/19 12:20 PM.
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Re: 505 stroker LSA
[Re: 1968fury]
#2635337
03/21/19 08:18 PM
03/21/19 08:18 PM
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Joined: Jan 2003
Posts: 15,439 Val-haul-ass... eventually
BradH
Taking time off to work on my car
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Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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I keep reading that stroker engines like a wider lobe separation angle. "It depends..." on the combination. (It also depends on who's writing what you're reading.)
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Re: 505 stroker LSA
[Re: 1968fury]
#2635364
03/21/19 09:04 PM
03/21/19 09:04 PM
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Joined: Jan 2003
Posts: 31,022 Oregon
AndyF
I Win
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I Win
Joined: Jan 2003
Posts: 31,022
Oregon
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I keep reading that stroker engines like a wider lobe separation angle. Can someone explain why. I'm building a 505 with 11:1 comp trick flow 270 heads and a Indy dual plane with max wedge ports and I'm trying to figure out what cam to use. I'm leaning towards this Hughes cam http://www.hughesengines.com/Index/...mxhdCBUYXBwZXQsIFNvbGlk&partid=30281But have it ground with a 110 or 112 LSA 3:91 gear and a 4 speed Thanks That cam will work okay in a 505 with 3.91 gears and a four speed. How heavy is the car? I assume it is a street strip deal which is why you're using the dual plane? Are you going flat tappet due to budget reasons or something else? I'd probably use a hyd roller for street use and a solid roller for drag race but a solid flat tappet can work if you're working with a tight budget.
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Re: 505 stroker LSA
[Re: AndyF]
#2635374
03/21/19 09:21 PM
03/21/19 09:21 PM
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Joined: Sep 2014
Posts: 4,457 Washington
madscientist
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Washington
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This is a decent article but beware of term confusion. The author says tight LSA cams have more low end torque but what he really means is that they have more mid-range torque. The low end torque (1500 to 2500 rpm) isn't very good when you have a lot of overlap. The author is looking at the graphs which start in what would be the mid-range for a street engine. So it really depends on what you are trying to accomplish. A race engine with a 5000 rpm stall converter will tolerate a tight LSA cam much better than a muscle car cruising to the Nats with the overdrive engaged and the AC on full blast. https://www.hotrod.com/articles/camshaft-shootout-lobe-separation-angle-tested-explained/ Andy is making some good points. The definition of the RPM range under consideration has to be CLEARLY defined. If I'm talking about bottom end, I'm talking about the bottom RPM range of the gear change, launch RPM minimum, minimum RPM in the corners of a circle track car. If we are talking about forcing an engine/drivetrain/chassis to deal with an RPM range so low you get bucking that's a different discussion. It's hard for me to conceive of a combination so bad with a stroke length of 4 inches or longer having cruise RPM issues that I just have a hard time thinking how far off you'd have to be to get there.
Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
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Re: 505 stroker LSA
[Re: moparx]
#2635549
03/22/19 12:02 PM
03/22/19 12:02 PM
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Joined: Jan 2003
Posts: 14,496 So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
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So. Burlington, Vt.
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I boil it down to this.......
Put a cam in the motor that makes sense for what you’re doing with the car.
In 95% of the motors people are building, there are compromises made as part of the build, for one reason or another. The cam is just another component that almost always has some compromises designed into it, to make it fit within some parameter of the build that isn’t quite optimum........ whether from a cost standpoint, compatibility with existing components, or how the motor will be used in the vehicle(and pretty often.... all of the above).
How much power you’re trying to make is almost always several rungs down the ladder in terms of priority when it comes to figuring out what cam to use.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: 505 stroker LSA
[Re: AndyF]
#2635562
03/22/19 12:24 PM
03/22/19 12:24 PM
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Joined: Jan 2003
Posts: 4,296 Chicago, IL
TonyS451
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master
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Chicago, IL
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Yeah I used to think about cams the same way but then I started to run into people who had read my race engine articles and used the same cam in their street car and they weren't so happy. A 700 hp pump gas engine sounds like a cool thing to build but if you have a C body and your wife just wants to cruise at 70 mph to a car show in overdrive with the stereo and the AC on then it isn't a good fit. Too much overlap makes the engine run poorly at 1800 rpm even if it has a 4.25 stroke.
One thing I've noticed over the years is that even though this is the race forum a lot of people building street cars post questions here. Some of them don't know that the advice they are getting won't work very well for them. Many times the person making the post doesn't bother to tell us how the car is being driven so people just assume it is a race car. It is a classic failure to communicate.
Personally I think that cams that are too big have turned more people off of hot rodding than anything else. I know of a bunch of backyard mechanic type of guys who bought a big cam for their car then just ran out of patience trying to get the thing to run. Some of those cars got parked, some got sold. Too big of a cam is a real killer when a guy also has a big double pumper carb and a mechanical distributor. That is a nasty combination for an inexperienced mechanic to tune their way out of. A lot of guys just never get it working. The cars are hard to start, take a long time to warm up, belch black smoke and smell bad. Eventually everyone gets tired of it....... This response should be a sticky on top of the race forum. I'm probably a perfect example of the guy who posts in race forum but doesn't have a race car. I'm much more interested in performance stuff, but don't actually own a race car. I built a 700hp "street car" years ago and the only time I had fun with it was when I was at the track (and not breaking anything). Its taken me a few builds, but I think Im finally getting it. Or im just getting soft . One thing is for sure, Andy is the Mr Myagi of Moparts.
2 kids and a dog
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Re: 505 stroker LSA
[Re: AndyF]
#2635650
03/22/19 05:41 PM
03/22/19 05:41 PM
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Joined: Jan 2008
Posts: 35 Livonia,MI
1968fury
OP
member
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OP
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Joined: Jan 2008
Posts: 35
Livonia,MI
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I keep reading that stroker engines like a wider lobe separation angle. Can someone explain why. I'm building a 505 with 11:1 comp trick flow 270 heads and a Indy dual plane with max wedge ports and I'm trying to figure out what cam to use. I'm leaning towards this Hughes cam http://www.hughesengines.com/Index/...mxhdCBUYXBwZXQsIFNvbGlk&partid=30281But have it ground with a 110 or 112 LSA 3:91 gear and a 4 speed Thanks That cam will work okay in a 505 with 3.91 gears and a four speed. How heavy is the car? I assume it is a street strip deal which is why you're using the dual plane? Are you going flat tappet due to budget reasons or something else? I'd probably use a hyd roller for street use and a solid roller for drag race but a solid flat tappet can work if you're working with a tight budget. Yes street/strip car I go to the track once a month. I believe the car is about 3600 lbs now (318 3spd on the tree) bottle cap hubcaps,radio delete car. I'm using the dual plane because I can't find a 337 intake and I don't want to cut a hole in the hood. I'm using a solid lifter cam because I love the way they sound with the rockers making noise. I filled out the form on comp cams website for them to recommend me a cam and they never got back to me. Thanks for all the responses
71 scamp 340 509 cam 456 gear,68 fury1 318 3spd on the tree,50 merc flathead 3x2 3spd w/overdrive
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Re: 505 stroker LSA
[Re: 1968fury]
#2635658
03/22/19 06:00 PM
03/22/19 06:00 PM
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Joined: Feb 2005
Posts: 4,313 Prospect, PA
BSB67
master
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master
Joined: Feb 2005
Posts: 4,313
Prospect, PA
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. I'm using a solid lifter cam because I love the way they sound with the rockers making noise.
Thank goodness. I was starting to think that I was the only one around that still does.
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Re: 505 stroker LSA
[Re: AndyF]
#2635681
03/22/19 07:45 PM
03/22/19 07:45 PM
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Joined: May 2003
Posts: 6,562 Downtown Roebuck Ont
Twostick
Still wishing...
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Still wishing...
Joined: May 2003
Posts: 6,562
Downtown Roebuck Ont
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Too much overlap makes the engine run poorly at 1800 rpm even if it has a 4.25 stroke. Truer words have never been spoken. Add EFI to the mix if you really want to add insult to injury. Mine has an MP509 with a 4.15 stroke. It did have 1.7 rockers. It seriously swung the torque needle at 1500 and was at 500 ft/lbs by 2000 but was seriously not happy at part throttle anywhere in that range with TBI. When I find something else to put it in I think I'm going to look at something similar to the MP528 but with a tight lash or hydraulic lifter. It has a fairly wide LSA, 114? Andy can testify to what it can do compared to "modern" grinds. Seems like a decent choice for a mostly street application if you have a full quiet exhaust system and need some manifold vacuum. Kevin
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Re: 505 stroker LSA
[Re: AndyF]
#2635721
03/22/19 10:07 PM
03/22/19 10:07 PM
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Joined: May 2008
Posts: 5,399 Aurora, Colorado
451Mopar
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Aurora, Colorado
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This is a decent article but beware of term confusion. The author says tight LSA cams have more low end torque but what he really means is that they have more mid-range torque. The low end torque (1500 to 2500 rpm) isn't very good when you have a lot of overlap. The author is looking at the graphs which start in what would be the mid-range for a street engine. So it really depends on what you are trying to accomplish. A race engine with a 5000 rpm stall converter will tolerate a tight LSA cam much better than a muscle car cruising to the Nats with the overdrive engaged and the AC on full blast. https://www.hotrod.com/articles/camshaft-shootout-lobe-separation-angle-tested-explained/ The confusion with the Low End Torque comments is in how the author relates (or does not relate) the difference between LSA, and ICL. I did not read the article, but have seen several where when talking about Lobe Separation Angle (LSA) the think the cams will be installed "Straight Up" with the Intake Center Line (ICL) the same number as the LCA. This means the author assumes the tight LSA cam will be installed more advanced than the wider LSA cam. If both cams have the same duration AND Installed Intake Lobe Centerline, the Wider LSA cam should have more low end power, but less mid-range (peak torque.) Mad Scientist made a good point of not getting wound up about LSA. If the cam is designed looking at the specific opening and closing valve events, then the Duration, LSA, and ICL get determined by them, not the other way around. The duration and LSA are just an easier way to describe and compare cams than Open/Close events.
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Re: 505 stroker LSA
[Re: fast68plymouth]
#2636089
03/23/19 07:20 PM
03/23/19 07:20 PM
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Joined: Feb 2005
Posts: 4,313 Prospect, PA
BSB67
master
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master
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Prospect, PA
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I boil it down to this.......
Put a cam in the motor that makes sense for what you’re doing with the car.
In 95% of the motors people are building, there are compromises made as part of the build, for one reason or another. The cam is just another component that almost always has some compromises designed into it, to make it fit within some parameter of the build that isn’t quite optimum........ whether from a cost standpoint, compatibility with existing components, or how the motor will be used in the vehicle(and pretty often.... all of the above).
How much power you’re trying to make is almost always several rungs down the ladder in terms of priority when it comes to figuring out what cam to use. This. I know exactly what I would put in it if it were mine. If I posted it I'd get flamed by most everyone. It comes down to the OP getting really really clear on what he wants and then consulting with a professional.
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