solid cam for a 383 sleeper

Hi everyone. I have a 1970 challenger rt se with a 383 bored 0.040 over, lunati 220/226 60302 cam, stealth heads shaved 0.040" kb400 pistons giving roughly 9.4:1, 770 and 750 holley vac and mech carbs available, stock HP manifolds with super turbos and stock exhaust piping, intake is dp4b. P/B and P/S, also have running a/c but having it work at idle is not a must.
Rest is 727 trans with stock histall vert (flashing 2600) , rear is 3.55SG with f70-14 (3000rpm at 62 mph). Car is numbers matching.
Car goes nice 5.6s 0-62mph, 13.9 best ET, 100mph trap speed. Problems with tracion in 1st, I have to take off at no more than 1200 rpm, shifting at 5100 rpm.

Question - if i wish to switch to a solid cam, lets say MP 528 BUT leaving everything as is (I have crane gold 1.6 rockers laying around) - will I gain anything or just choke the poor 383
I also considered comp xs268s but would like something less chebby... hughes solids are to long duration...

I read 528 goes well with manifolds but with more cubes than I have.

Anyone runs such combo with a 528 solid? I don't want to change the converter.

thanks

I think the MP .528 might be a little too big for your engine combo. It had a little bit of a lope in my 470 so it would probably have a lot more lope in your 383.

I have a Racer Brown solid flat tappet that is a little bit smaller than the .528 cam. I used the Racer Brown solid in some dyno testing and it was a bit too small for my 470 but it would probably work in your 383. If you lived close by I'd let you try it out but Poland is a long way away!

If you have been bitten by the "go fast" bug, my advice is to leave it as it is for now and start looking at stroker kits. Whether you simply go to a 3.75 stroke in your 383, or opt to find a 400 block and push out to 470 cubes or more.... You'll be happier in the long run than just trying to squeeze a little more out of the numbers matching 383, because that's all you're going to get with that plan; a little.

A 470 could be built to idle easy and be just as drivable as you are now, but still stomp every cammed up 383 you will run across.

And by the way.... In order to qualify as a "sleeper", it has to actually be fast. An E-body flashing RT badges and running 13's is not really a sleeper in my book.

Thanks for advice. By sleeper I meant stock looking engine but with some more oomph to show ricer boys their place. Engine has just a shy over 3 years and I'm reluctant to put in the stroker kit + all that machining once again. I live in Poland and during my rest had lots of problems with mechanics not knowing what mopars are about.
A friend of mine has a 68 charger with the same 383 but running 2330 hughes cam and headers with 3.23 gear and like 27" tires and it feels his motor has 20% power (especially above 60mph).
However I dont want to ruin stock look with these damn headers... which surely would help.

@AndyF - can you post thet racer brown cam specs?

By the way why 3.75 (438) and not 4.25 (496) ? More fun same cost.

The 3.75 you can use a ground stock 440 crank - in the usa much cheaper than a new one

4.25 needs the block cleaned up internally to stop bits a pieces hitting things - in a "B" block it -generally- means external oiling too

there are concepts of bigger valves needed for the flow capacity and valve shrouding on the smaller bore too, many dont sweat that stuff too much though

Off the line @1200... look into your traction control before adding more power, cause it aint going to do you any good if it cant hook up

When I ran a very mild 383 in my old Dart I did have headers on it. But the 383 was a stock bottom end and I mean stock as it was not even bored as it was stock bore. I had 452 heads I milled to get a true 9.5 comp and I did some mild pocket porting on the heads. All the internals were stock other then the MP .484 cam and I had it on a 104 ICL. I used stock rockers and pushrods and had a Comp single spring on the valves. Everything else was bolt on's like the RPM intake and 750 Holley DP. It had 3.91's and weighed 3560 with him in it. It ran 12.30's @ 110 with a 12.31 best. I was impressed with how nice that mild 383 ran. Ron

I know I can get better performance with sticky tires but I want to stick to the stock look.
This is not a race car, just a resto which I want to kill some more ricers with. I don't expect FAST class performance with my combo. Ever.

@383man - your is hydraulic 284, 528 is solid 284 so they are not comparable, probably you also had quite loose converter.

Returning to the core - can you recomend a solid cam acting like my voodoo (60302) or a tad bigger? I have adjustable 1.6 rockers for it.

thanks

Looking at his combo he is running a cam that is 1/2 step larger than yours. That's minor, IMHO maybe 10 hp in your engine. The major difference between you two is HEADERS. I mean, shoot he's running less gear in a car that weighs the same maybe even more.

Feeling more power is actually feeling the effects of torque. Something long tube headers do is increase torque below the torque peak.

I do not see a cam change as being beneficial to you unless you go radical on axle ratio and converter.

Torque with exhaust manifolds is increased by increasing either compression ratio or displacement.

One last thing, ignition curves can really affect the way a car feels on acceleration. This is where I'd start.

R.

i think more power would be gained by sending those stealth heads out and bringing the flow up to specs than taking a chance on over camming that 383. 383's are easy to over cam. i do have experience with that 2330 cam and like it but you probably wouldn't gain that much for the time and money spent.

if you really want to wake it up. add a hydraulic roller cam. the fast ramp will get the cylinders filling quickly. you want one with a split duration that is longer on the exhaust so the manifolds can empty the cylinders properly. i'm not the one to get to spec the cam, but look at the engine combo that was run by steve dulcich in the engine masters challenge. he did have headers so that's a big plus for him, but you have stealth heads so that's a big plus for you.

23-710-9

Do you have hood clearance for a Performer RPM? 5100 isn't alot of RPM for a 383 with Stealth heads. Maybe with a 440, but I think the 383 should wind up a little tighter.

The times are respectable but I think you could/should be able to get closer to 105 mph out of that combo, and I'd think it should wind up to 5500 or 6000 with ease. The DP4B is a decent piece but an RPM may help. Have you exhausted tuning efforts?

I agree with others here... you are on the verge of over-camming your 383.

I'm sure that you know this, but a solid cam is generally compared to a hydraulic cam this is 10-ish degrees smaller due to duration taken up by the lash.

I have a Scott Brown 232/242 solid flat tappet in my 383, but I have 3.91s, 3500 converter, headers, and more compression than you... and its still kinda lopey.

Leave the motor alone and use a looser converter. Another 500 rpm of stall will wake things up.

Sorry as I see you said solid cam. My converter in the Dart was a Turbo Action tight 3000 stall 10". Ron

Wow, many answers
Performer RPM was hitting the hood with stock dual snorkel air filter so I picked DP4B which fits.
Ignition is MP dizzy recurved to 18 initial 39 total with mopar orange/blue box (blue has nicer idle but doesnt pull above 5k).
It's true I could shift her at higher rpm like 5500-5700.
Higher stall won't help mi at takeoff with f70-14s...

KISS..
You effectively talked me out that solid cam swap I'll stick with that voodoo and maybe change the old stock exhaust pipes with a new mandrel bent 2.5" system first.

Thanks everyone for your contribution, great Mopar family. Greetings from Poland:

Get another Air cleaner and modify it into a drop base and think about another ignition box, the orange box might pull better above 5000 rpm but it starts to retard timing at 4000 rpm.

I'm preparing an order at summit - their chrome MP boxes are reliable?

Great photos, Willard, thanks for posting them. By the background Poland looks amazing.

I agree!
That may get you on track for more performance. Pay more attention to your cam/working compression relationship from those heads (383's like smaller chamber volumes and quench. Lousy piston selection though, unless you go stroker). 440's make power somewhat easier having the large chamber with or without quench (440 piston selection is BETTER). Once you have that bit of info, your newfound ignition timing and carb tune will help net you the power you are looking for. FWIW stickier tires and a bit more gear can help
make the combo work better. Want to keep the stock hood look? Maybe an M1 or SD manifold may work. Food for thought?

I've read this post several times and am a little conflicted on what advice to give.

One side: It is a stockish, pump gas 383 probably in a 3900 lb car pushing 100 mph in who knows what atmospheric conditions. Conclusion: not bad.

The other side : A 383 as you described only pulling to 5100 rpm. Conclusion: something is not right. If your buddy's car is noticeably faster and everything else is about the same, that kinda supports this conclusion. What rpm is he pulling? Maybe do a detailed comparison between the two and see if his verses your performance makes sense.

If it is really falling off at 5100, that is not right and you should look in that direction. Ignition box replacement is probably a decent first step. Next is fuel delivery. Best test in my opinion is an inline pressure gauge near the carb that you can read at WOT through the rpm range while driving. I think you should have at least 3.5 psi, or so.

Twice I've had mufflers fail internally that just suck power away big time, but you never know it. The only reason I found it was because I was going to the track regularly, and I lost 3 mph between visits. FWIW, both times they were Super Turbos.

If that is not it, maybe your lifters/valve train are not keeping up with the high rate Voodoo cam.

And to your original question, I think that a solid lifter cam is always a good choice if you don't mind the clatter. Kinda eats away at that stock thing though.

First - differences between my challenger and my friends red 68 charger:

- both 383s with KB400 dome pistons
- my stealths (stock valve springs, better locks) vs his 906s - both shaved approx 0.045"
- my 220/226 with hughes lifters, degreed +4 deg vs 2330 cam
- my HP manifolds+ 2 1/4" stock exhaust and super turbos vs his tti headers + 2.5" exhaust and some magnaflows
- my dp4b vs his performer rpm
- my holley 770 street avenger vs his 800 thunder avs
- my MP electronic dizzy + noname blue box (this may be culprit of only 5k RPM) vs his mallory unilite (we both have blaster2 coils)
- my 3.55 + 26" bis ply vs his 3.23+ some 27" tyres
- my stock MP histall vert vs his hughes 2500
- both almsot stock 727s (my has cheetach VB)
- both PS/PB cars


My best times were at 50 deg F so good air but very bad traction so I definitely lost some time when taking off.

I guess I'm gonna first try chrome box cause I doubt It's valve float with such mild cam and quite quality lifters. Now we have deep winter so I cant try the car on the street.

Second, I'll check the fuel delivery at WOT. Gauge and fittings ordered at summit already.

Third, I'll have a new 2.5" exhaust made and stick to HP manifolds.

I'll refrain form tinkering with solid cam for now. You're all right that for a resto car it's not the best way.

I'll let you know what are the results when the snow is gone.

First verify you have adequate fuel delivery and the proper valvesprings in the motor. As you desribe the 383 is should want to rev to at least 5800 even with manifolds. I lije solids in 383's and 'generally' anything that makes a comparable 340 quicker will make a 383 quicker as well. What that means is, treat it more like a small block in terms of tuning.

Id like to run a solid with about 232/238 @ .050 and ~.520-ish lift on a 109-111 spread in at around 105 since you want to 'use it up' with a relatively low 6100-6300 rev cieling with the manifolds. Combined with a fairly tight 9 1/2" or 10" converter. That would shave about a 1/2 second off your times and the car will be more fun to drive as well. the cam will have a wider powerband ( come in sooner and stick around later) .

383's are fun and make good power, you just got to get them to the sweet spot quickly and let the revs do the rest.

the comp cams xs268 might work but i'd spread the lobe separation out. i've been thinking about an engle ep-43 intake lobe/ep-46 exhaust lobe for a build; it might work.

What mod could you make that would give you as much return as a $500 150 shot plate kit?

NOS is out of question - must look stock under hood. I can afford 3x nos kit to get the same result and have the car looking stock.
As I already have nice 1.6 adj rockers and I'm tempted to TRY the solid cam. Can you recomend any available cam with specs like Streetwize posted? Or I need to custom order it?

I can try the tighter converter first - any recommendation? I live in poland and i need something off the shelf.

Valve springs - they are stock stealth springs, they have 3 years now so I doubt they are a problem, moreover I don't have equipment to measure their pressure...

a Tight 9 1/2" or 10" T/A converter will still stall higher (~3000-3200) than either of the heavier (assumed) 11" verts you have. The advantage (especially with the solid cam) is the 383 motor will rev quicker and pull harder through the gears and the solid will help the smaller converter drive more like stock (i.e., more torque/response than a hydraulic) under normal driving.

A solid cam (when adjusted for lash) will idle and drive like a 10 degree @.050 smaller Hydraulic, but the faster valve action and .200"-up duration numbers will build torque sooner and rev higher. I immediately thought of the old Ultradyne NF56 lobe which is ~235@.050 and 150@.200 and .512" lift designed for an .875 (Ford) lifter profile, but in your case I would PM Fast68Plymouth and get him to send you a Comp Custom grind.

A cam such as that would definitely make a 383 "snap" a bit quicker and be more responsive and make ~15-20 more lb/ft across a broader powerband than a hydraulic, so for that reason primarily...I believe solids really help when you have a short stroke motor (that naturally WANTS to rev and needs all the extra torque it can get off the line) like a 340 or 383.