The other 451, cam choice w/manifolds?

Posted By: 1KoolBee

The other 451, cam choice w/manifolds? - 09/01/14 08:27 AM

I decided to move forward on a "beater" motor for my '68 Bee and stash the original 383. I had another '68 383 block laying around so I dropped it off at my not-so-local anymore machine shop back in the high desert. Another moparts member made me a great deal on some .030 1.320 CH Diamond pistons, I picked up some BBC 6.700 K-1 H-beam rods on clearance from Wiseco, and ordered a 3.915 B-Motor crank from 440 source. I plan to run Eddy heads so this setup will yield 451 cubes at about 10.5 compression. I want to keep a somewhat stock appearance so I plan to run the factory HP exhaust manifolds and 2.5" factory style 440 exhaust. The 383 had a Performer RPM and an 800 Edelbrock AFB so I'll be swapping that setup onto the 451. A fresh coat of turquoise paint and a 383 pie-tin will go a long way to hide the true nature of this motor.

Question is, is there a better "manifold" cam out there than the old .528 MP solid? I know Andy's "manifold" 471 ran best with that cam & this motor is really just a smaller version of his 471. That was a few years ago, has anyone actually run something that works better?

FWIW Gears are 3.73 & I plan to drop the 3000 converter to about a 2500 converter

Posted By: Chris2581

Re: The other 451, cam choice w/manifolds? - 09/01/14 02:32 PM

IMHO...that 528 cam is going to be very hard to beat in performance.It's really a good cam,I've used it in 2 engines with great results.

Posted By: RUNCHARGER

Re: The other 451, cam choice w/manifolds? - 09/01/14 05:20 PM

I like the 528 as well.

Sheldon

Posted By: HYPER8oSoNic

Re: The other 451, cam choice w/manifolds? - 09/01/14 05:56 PM

The .528 MP cam wins hands down. Any doubts, PM Andy F.

Posted By: AndyF

Re: The other 451, cam choice w/manifolds? - 09/01/14 07:45 PM

Every cam guy I talked to told me that they could grind a cam which would work better than the old MP .528 grind. I tried all the cams that people sent me and none of them actually worked better.

I'm pretty sure that if I picked up the phone today and called the cam grinders everyone would tell me again that yes they do have cams that work better than an old purple shaft. Question is do they, or are they kidding themselves?

Dwayne Porter is about the only guy who I would expect to deliver a cam that works better than the MP 528.

Most cam vendors do not have much experience with exhaust manifolds so they are really lost when it comes to designing a cam for that application. They'll tell you that they can grind a cam for you but when you dyno test it and tell them the numbers then they'll come back and say "oh yeah, looks like we need to adjust some things". That is okay if you're rich and have lots of time but most guys can't afford to do that much testing.

Posted By: 1KoolBee

Re: The other 451, cam choice w/manifolds? - 09/01/14 10:52 PM

Thanks guys, 4-0 pretty much sums it up! Thanks for the articles Andy, its always great to have someone take the time (and $)to prove what works for real & what doesn't. Funny how these old Mopar grinds are regularly dismissed by folks as "old technology" but the numbers show they are still pretty tough to beat when compared apples to apples:

https://board.moparts.org/ubbthreads/show...rue#Post7899803

Any thoughts on where I should start out on my jetting?

Posted By: AndyF

Re: The other 451, cam choice w/manifolds? - 09/01/14 11:37 PM

Always start the testing with stock jets in the carb. The carb mfgs send all performance carbs out the door slightly rich so dead stock jetting is usually a safe place to start.

Posted By: 1KoolBee

Re: The other 451, cam choice w/manifolds? - 09/06/14 06:22 AM

Thank Andy, BTW your engine building book is great!

Posted By: 1KoolBee

Re: The other 451, cam choice w/manifolds? - 12/17/14 05:55 AM

Quote:

I decided to move forward on a "beater" motor for my '68 Bee and stash the original 383. I had another '68 383 block laying around so I dropped it off at my not-so-local anymore machine shop back in the high desert. Another moparts member made me a great deal on some .030 1.320 CH Diamond pistons, I picked up some BBC 6.700 K-1 H-beam rods on clearance from Wiseco, and ordered a 3.915 B-Motor crank from 440 source. I plan to run Eddy heads so this setup will yield 451 cubes at about 10.5 compression. I want to keep a somewhat stock appearance so I plan to run the factory HP exhaust manifolds and 2.5" factory style 440 exhaust. The 383 had a Performer RPM and an 800 Edelbrock AFB so I'll be swapping that setup onto the 451. A fresh coat of turquoise paint and a 383 pie-tin will go a long way to hide the true nature of this motor.

Question is, is there a better "manifold" cam out there than the old .528 MP solid? I know Andy's "manifold" 471 ran best with that cam & this motor is really just a smaller version of his 471. That was a few years ago, has anyone actually run something that works better?

FWIW Gears are 3.73 & I plan to drop the 3000 converter to about a 2500 converter

After reading and re-reading Andy's "Lobeology" article and talking to Dwayne Porter a couple times, I'm contemplating going with a custom Comp grind for my 383/451 to try to improve on the MP .528 cam, maybe get a little more lift & get the lash down to the .016-.020 range. One option is to run a comp xs-282s solid on 112 centers. Another thought was to run a pair of comp 6581 MM lobes on 112 centers. The "net lift" specs with 1.6 rockers are as follows:

MP .528: 241/241 .535/.535 112 Lobe centers
Comp 6581/6581: 239/239 .557/.557 112
Comp xs282s-12: 244/252 .537/.561 112

Anyone run the XS282s with manifolds?
Do the MM lobes survive on the street? I was planning to run EDM lifters, is nitride required too?

Or am I overthinking this?

FYI-For heads I'm going to run Porter Racing prepped Stealth Heads so I can have straight plugs.

Posted By: BradH

Re: The other 451, cam choice w/manifolds? - 12/17/14 10:55 PM

Questions / comments:
1. What did Dwayne P. suggest? And are you second-guessing him?

2. I'd be hesitant to run MM-type lobes w/o both EDM lifters AND nitriding... and I'm not so sure they'd be the right choice for an engine getting a lot of street miles. Something milder will be kinder to your valve springs, etc., over time.

Posted By: lewtot184

Re: The other 451, cam choice w/manifolds? - 12/17/14 11:00 PM

what about angle plugs and cast exhaust manifolds?

Posted By: 1KoolBee

Re: The other 451, cam choice w/manifolds? - 12/18/14 01:23 AM

Porter prepped stealth heads, straight plugs.

Posted By: 1KoolBee

Re: The other 451, cam choice w/manifolds? - 12/18/14 02:19 AM

Quote:

Questions / comments:
1. What did Dwayne P. suggest? And are you second-guessing him?

2. I'd be hesitant to run MM-type lobes w/o both EDM lifters AND nitriding... and I'm not so sure they'd be the right choice for an engine getting a lot of street miles. Something milder will be kinder to your valve springs, etc., over time.

I don't consider weighing the facts as 2nd guessing. You make a good point about wear & tear. Sounds like if I want to do something like option 2, I need to talk to Dwayne about a street roller but Andy Fs testing showed that more is not always better in this case. I have no doubt that Mr Porters recommendation will perform well but it's not clear to me that the extra expense of a custom solid or roller will buy much, if any, improvement in performance .

Posted By: BSB67

Re: The other 451, cam choice w/manifolds? - 12/18/14 03:03 AM

Quote:

Questions / comments:
1. What did Dwayne P. suggest? And are you second-guessing him?

2. I'd be hesitant to run MM-type lobes w/o both EDM lifters AND nitriding... and I'm not so sure they'd be the right choice for an engine getting a lot of street miles. Something milder will be kinder to your valve springs, etc., over time.

The motor will respond nicely to faster ramps. It is just a trade off on valve train abuse and running closer to the edge. There are several profiles between the XE and MM profiles in aggressiveness, but most are recommended to have direct face oiling and nitriding.

Posted By: JohnRR

Re: The other 451, cam choice w/manifolds? - 12/18/14 03:07 AM

Quote:

what about angle plugs and cast exhaust manifolds?

Andy ran the angle plug ebrocks and manifolds ,there rear cylinders on both sides get close to the manifold downpipe.

Posted By: BSB67

Re: The other 451, cam choice w/manifolds? - 12/18/14 03:10 AM

Quote:

......but it's not clear to me that the extra expense of a custom solid or roller will buy much, if any, improvement in performance .

It will give improvement, and I would call it "much". "Much" is relative and subjective, however.

Posted By: JohnRR

Re: The other 451, cam choice w/manifolds? - 12/18/14 03:20 AM

Quote:

Quote:

Questions / comments:
1. What did Dwayne P. suggest? And are you second-guessing him?

2. I'd be hesitant to run MM-type lobes w/o both EDM lifters AND nitriding... and I'm not so sure they'd be the right choice for an engine getting a lot of street miles. Something milder will be kinder to your valve springs, etc., over time.

I don't consider weighing the facts as 2nd guessing. You make a good point about wear & tear. Sounds like if I want to do something like option 2, I need to talk to Dwayne about a street roller but Andy Fs testing showed that more is not always better in this case. I have no doubt that Mr Porters recommendation will perform well but it's not clear to me that the extra expense of a custom solid or roller will buy much, if any, improvement in performance .

I was on the phone with Dwayne the other day going over the same stuff, I have a Solid roller that came out of Wayne Smothers 440 cube F.A.S.T. 69 A12 Bee , it went 120 something in the 1/4 with high compression. I'm finally screwing together my 383 based 451 F.A.S.T. build this winter and was originally asking about throwing that roller in a 10.0 383, he said it was too big and it wouldn't accomplish what I wanted ... 12.50 index class at the local track ... without wailing the pee out of the 383, plus slicks and headers w/no exhaust.

Dwayne has had his hand in a number of the F.A.S.T. BB wedge motors so I would go with what he says about cams ... be warned that a cam for exhaust manifolds will not work very well should you decide to swap to headers.

If you go with a Comp flat tappet get it nitrided and use the EDM lifters ... worth the money for piece of mind after I had a shelf comp go bad 6 minutes into break in ... better safe than sorry. I have/had a Comp solid that he had done for me , I for the life of me can't figure out where I put it when I pulled it out of the assembled long block when he talked me into upping the compression from 11 to 12.5 ... I still have the cam card so I can give you the grind number if you want to try that .

Posted By: BradH

Re: The other 451, cam choice w/manifolds? - 12/18/14 03:26 AM

Exhaust manifolds are restrictive and make cam selection even more critical IMO. Too much overlap (whether the result of tight lobe centers or fast ramps) causes excessive reversion that hurts torque.

Faster ramps are not always better, dual pattern cams are not always better, and unless your heads flow a lot at high(er) lift, the benefit of a street roller over a good solid flat tappet can be minimal.

And tell Dwayne I said "Hi" when you call him next time.

Posted By: gch

Re: The other 451, cam choice w/manifolds? - 12/18/14 03:59 AM

If you want a little more lift out of the .528 then run some 1.6 rockers.Ask the experts if this will have any negative effects with the manifolds.

Posted By: 1KoolBee

Re: The other 451, cam choice w/manifolds? - 12/19/14 05:27 AM

Quote:

Exhaust manifolds are restrictive and make cam selection even more critical IMO. Too much overlap (whether the result of tight lobe centers or fast ramps) causes excessive reversion that hurts torque.

Faster ramps are not always better, dual pattern cams are not always better, and unless your heads flow a lot at high(er) lift, the benefit of a street roller over a good solid flat tappet can be minimal.

And tell Dwayne I said "Hi" when you call him next time.

I agree totally. Andy F's article clearly demonstrated that when it comes to a manifold engine, limited overlap and fast ramps are about the only things that made a real difference, and even then only a couple of the custom cams were marginally better than the .528. And the smaller Racer Brown cam was surprisingly close to the .528 with great punch at lower rpm.

Then when you look at Keith's "Fading Color" article, only 1 solid offered a substantial power increase over the MP .590 with fairly minor variations of lift/duration. This leads me to the conclusion that all of these customs might offer marginal gains ( or losses) until you hit that "sweet-spot" of lift, ramp, duration, & lobe angle where respectable gains can be had.

Problem is since every engine combo is slightly different, finding that "sweet-spot" requires either previous experience with a given combo or a wad of cash & a dyno. Obviously Dwayne, Andy (and others) have plenty of real life experience with similar setups to mine, I'm sure either of their recommendations will work well. Just trying to arrive at the best possible choice when its time to pull the trigger next month.

Thanks for everyone's help.

Posted By: 1KoolBee

Re: The other 451, cam choice w/manifolds? - 01/10/15 01:49 AM

Quote:

Porter prepped stealth heads, straight plugs.

Just an update, Talked to Dwayne yesterday, ported Stealth heads almost done. We talked quite awhile about cam ideas. We settled on a couple of comp lobes with similar intake specs as mopar .528 with faster ramp & a little more lift. Exhaust a little more lift/duration but not much. Wide centers. In theory it should run pretty strong but the bonus is tight lash & nitriding as insurance. Dwayne is great to talk to & very knowledgeable, I can see why he's so well respected. I'll keep you posted on how it runs. BTW, I managed to get my Bee down here from storage last weekend. Its like being reunited with an old friend!

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Posted By: FastmOp

Re: The other 451, cam choice w/manifolds? - 01/10/15 02:50 AM

You should have priced a Herbert roller kit.

Posted By: 1KoolBee

Re: The other 451, cam choice w/manifolds? - 01/10/15 06:20 AM

Why? Do they have a grind proven to work well with factory exhaust manifolds?

Posted By: goldmember

Re: The other 451, cam choice w/manifolds? - 01/10/15 06:36 AM

Quote:

Why? Do they have a grind proven to work well with factory exhaust manifolds?

I'm guessing it was a joke,based on a cheap antique roller setup VS. a flat tappet with nitriding etc in hopes of a cam that doesn't fail shortly after fire up?? Hope things work out well for you.