What we have here
505 stroker
Stealth Heads very mild porting (just tidy up)
10.5 comp with assembled quech at .040
Hyd roller cam with 230/230 @ .050. lift .576/.568 on 112 lobe installed with no advance
Factory six pack induction
Factory Hipo exhaust manifolds with twin 2 1/2 exhaust with X pipe
On the engine dyno this made max TQ 575 @ 3350. Max HP 494 @ 5300 (this was with a twin 2 1/2 exhaust and mufflers hooked up)

The car:
70 Cuda
auto with 2200 converter
3.23 posi with 28in tall tires
Power brakes,power steering.

I know obviously a set of headers and maybe a 3in system would do wonders for this combo but the ex manifolds need to stay. The dyno operator has told the owner he is leaving some on the table with this cam chioce.

Anyone care to provide some input on this?
Thanks Tim

Andy F has written an article about using manifolds on a big block http://www.moparts.org/Tech/Archive/bb/550hp.html
Gus

I have a copy of Andys book and tried to follow his build closly regarding camshaft selection using a hydralic roller instead of the flat tappet solid. From what I have read the six pack intake is very similar in performance to the RPM performer. Admittedly we dont have the 3in pipe coming of the manifolds.

You can probably go about 10 degrees larger and still have a decent idle. I was using 5 or 6 degrees larger with a 470 inch engine.

Thanks for chimming in Andy. Do you think it is a worthwhile change given the exhaust size gearing and tire height. I know the cam is 13 degrees smaller @ .050 but I thought the fact that it was hydralic, a roller and the extra lift would have made it pretty close in performance.

I have a 508 with Stage V wedge heads Six Pack intake. HP's with extrude honing into 3" TTI X piped with dynomax race magnum mufflers. 2.94 sure grip and 9.5" Ultimate Converter Concepts totque converter.

Scott Brown at Competition Components spec'ed my cam and converter. It flat out screams and is a torque monster.

Never had this combob to the track......but 0 to 60 with all the tools and spares I took on the hot rod power tour the Runner had identical real time performance figures as a ZL1 Camaro....

Remember 2.94 gear in my 73 Road Runner over 4000# with all the tools spare tire jack stands jack etc. The B body trunk was full of metal.

That is one of Scott's older cams. im sure he has updated it by now.

scotty.brown@ymail.com
616-499-6223

Just depends how much free time and money you have to play with the engine. If you're retired and wealthy and have nothing better to do then ordering up a few different cams for some dyno testing can be good fun. Otherwise I probably wouldn't bother.

That converter is suspect to me.With that kind of torque it will likely stall higher and have a lot of slip while generating a lot of heat.Unless it was built for this motor I would suggest a quality unit for this motor.
Gearing is fine for a street car and with that much torque it will move fine.You want as big a tire as you can fit.It will roast the weenies at will.

Dwayne Porter (fast68plymouth) has a list of cams for sale on the 2nd page of the engines classified section for big blocks near the bottom, some of them say they're specifically for using with manifolds, here's the add, he would probably be the guy to talk to:


NEW-IN-BOX Comp cams street roller cam:

dur @ .015- 274/280
dur @ .050- 236/242
lift w-1.5-.564/.570
lobe sep.-- 113
valve lash- .016/.016
3 bolt design

this is just a XR274R ground on a 113lsa instead of the standard 110lsa.
this was done for applications that may want a smoother idle and/or higher engine vacuum(for power brakes), or those who are running exhaust manifolds or small tube/shorty style headers.

$289+ shipping

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NEW-IN-BOX Comp Cams custom solid flat tappet cam:

dur @ .020- 270/274
dur @ .050- 244/248
lift w-1.5-.546/.554
lobe sep.-- 113lsa
valve lash- .016/.016
3 bolt design

this is a fast rate, higher lift version of the popular MP528 solid lifter cam.
good for applications wanting decent idle quality, good throttle response, low end TQ and an extended power band.

this cam has been plasma nitrided and should be used with EDM style lifters.

$269+ shipping
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NEW-IN-BOX Comp custom roller cam:

dur @ .020- 276/276
dur @ .050- 246/246
lift w-1.5-.618/.618
lobe sep.-- 115
valve lash- .022/.022
3 bolt design

this is a cam for a FAST(Factory Appearing Stock Tire) type application where an extended power band is desired when using exhaust manifolds.
best with compression ratios over 11:1.

$299+ shipping

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NEW-IN-BOX Comp custom hydraulic flat tappet cam:

dur @ .006- 279/287
dur @ .050- 227/235
lift w-1.5-.479/.489
lobe sep.-- 112
3 bolt design

this is a cam i like to use as a noticeable upgrade from the std HP/6 bbl cam. 9.0-11.0cr, exhaust manifolds or headers, 2500-3000 converter, 3.23-4.10 gears.

dynoed at 435hp/490tq from a 446 with bowl blended 906's with 2.08/1.74 valves, 6bbl induction, and HP exhaust manifolds.

this cam has been plasma nitrided.

$269+ shipping

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the best way to reach me is to call me at my shop:
802-951-1955

email: porterheads @ gmavt.net

--------------------
68 Plymouth Satellite, 383, stock 906's, 3550lbs, 11.18 @ 123, 1.51 60'

PRH is a Comp Cams W/D......competitive pricing on entire line.
Custom cams available.
** dealer for Indy Cylinder Heads **

Post Extras:

What is the problem, or what are you trying to accomplish?

Is the car together and running?

Have you been to the track? What is the performance?

Will you go back to the dyno?

Guessing at what some of your answers might be, I would say leave it as is and take it to the track. Once you have some time driving the car, and in-car performance data, then you can get clear on what your goal is, and the guidance will be better.

---

I personaly dont have a problem with the cam selection, I made it based on other peoples published results and experiences with EX maifold combinations and taking into consideration the gearing, tire height, converter and vacum for power brakes and carb tunning.
The motor has been run in the car and seemed to be strong (easily overpowering the 275x60 tires), the tight converter worked well as did the power brakes. It did have an issue with stumbling onto the outboard carbs.
The motor was removed for an unrelated issue and it was decided by the owner to tune the motor on a dyno before putting it back in the car. It was discoverd during this process that the carbs were rich
and the stumbling issue was rectified, it was also discovered on the dyno that the motor liked a total of 36% timming and we only had 29% when it was in the car. So I would suspect the motor would be stronger now than when it came out of the car.
The car did not go to the track but I suspect the owner may wish to take to the track from time to time (with some sticky tires).
I belive the owner wishes to drive the car mainly on cruise nights and outings and basicaly wants a maintinance free motor with some extra power on tap (this car is a resto not a hot rod hence the dessire to have a stock apearing engine)

So this takes me back to my original question, does someone think there is a better cam choice for this package based on the critera above?
The dyno operater has informed the owner the motor dosnt have enough cam and he is leaving some performance on the table.
I posted this question as there are people out there with more experiance with these engines than me and I dont want to dismiss the dyno operaters sugestion out of hand.

With a 2200 stall 3.23 gears and 28 inch tall tires why bother should work great the way it is don't think you could change much with that and manifolds + 2 1/2 exhaust. and still have it work right.


You need a wholesale change 3000 stall 3.7 gears 3" X pipe exhaust (and made headers) then something in a 242 to 246 @.050 intake and 246 to 250 @ .050 exhaust might be the ticket

right now 2300 cruising is going to be 60 MPH so right where you want to be with this stall.



If you don't have a H pipe or X pipe at least add the H pipe!

I'd think your convert (or lack thereof) and gear is hurting the car moreso than the cam.

a 230@.05 camshaft on a 505 stroker certainly does leave something on the table as far as HP and Torque. So if peak HP and Tq is all someone is concerned about, by all means change the cam.
A more realistic way in my mind is to look at the area under the curve and consider how the car will be used and what is the realistic expectation for performance as well as drivability. That combo will make a very reliable street combo that will absolutely roast the tires any time you want to. No, it's not a high rpm screamer and I suspect from your post that, that's not what it was intended to be.
Personally I probably would've spec'd something slightly different, but I bet the owner has a lot of fun with it just the way it is.

The real problem is the dyno operator. It's easy to say "you're leaving power on the table" but a dyno isn't a street car. If its blowing the tires off as it is, what will more power do?

R.

This is why I asked the questions.

It sound like most of the owner's criteria are met. And his gauge for more power will simply be his butt-meter. He has a low maintenance fun to drive car now. You might not want to mess with that. Answer this, was he happy with the power/performance before the dyno run?

A little more power would be had with the first two cams that Dwayne has for sale above. The third cam will make even more power.

One of the problems with the hydraulic roller in an exhaust manifold car is that the ramps are pretty lazy from the seat to 0.050". So seat timing is relatively large relative to the 0.050" numbers. The manifold car will respond very favorably to less advertised duration with more 0.050" duration.

That's not a bad choice but a little conservative for the 4.25" arm in that motor, something around 238/242 @.050 .585/570 lift and 112-113 spread in at ~107-108 would give you close to the same intake closing but get the valve up and open a little bit earlier and help extend the powerband another 400-500RPM. 230 is a little short for a 500" motor IMHO it just limits the breathing up high when the stroker piston speed starts churning at a comparatively low RPM.

I had a 252/258 @.050 on 112 Straightline HR in my old 508 (the same motor I sold to Paul PHJ426) and it was really mellow sounding with headers....made MAD power and torque everywhere but sounded suprisingly docile at idle. That motor had headers though so with manifolds you don't want to run a lot of exhaust duration. The 'trick' to running exhaust manifolds with a stroker is you have to find ways to make the intake and exhaust tracts work 'on their own' since you're taking away any benefits the overlap draw at a proportionally lower RPM. An agressive higher lift intake, wider centers and a slower exhaust ramp to hold on to as much cylinder pressure as possible (for as long as reasonable) to push through the restrictive manifold.

My 'rule of thumb' with a street stroker is I want to put as big an intake lobe on it as I can....up to the point where it is just about to start killing torque at the low end of the rpm range/powerband...compared to a stock stroke motor that's a bit bigger than a 230 @ .050. I'm sure it works very well, but to me that's kind of a broomstick for a 505.

Too much torque down low makes it tough to hook and then you run out of steam too early....kind of like the Olds 455 or a 428FE used to.

Being a roller I'm sure they could regrind another 10-12 degrees into it....just on a slightly smaller base circle....on a stroker the 238/242 I suggested could be worth 40-50hp and 500 rpm with no appreciable loss of torque off the bottom just on extending the powerband 238 @.050 is about the smallest I would ever put in a 4.25" stroke street motor, in fact I just speced a Bullet HR for a similar combo for a customer in Austrailia.

If he doesn't mind going to a solid one of Fast68Plymouths grinds might be just the ticket but the .612 F.A.S.T. racing oriented grind I suspect will have too agressive of a ramp for normal street use....check with him well worth looking into.

Also a tight 9 1/2" converter (maybe 3200 FB stall /4200-4400 flash) would feel very good on the street and cruise nice and feel almost stock-ish tight at 65mph with highway gears behind a 505 and really allow that thing to roll-on... if you 'get it right' a 500 (with a manual VB) will accelerate about as hard from 45 mph IN HIGH GEAR as a stout 440 will kicking down to passing gear from the same 45mph roll.

The duration adv. is 280in/282ex at .006 lift. These are the Comp Cams XFI lobes.
I will present the altenatives provided to the owner!
Thanks for all the helpfull imput everyone.