The Dodge Challenger Message Board

i have a 440 with the 906 heads they been reworked and i had the piston 30 over using a edelbrock 750 carb and the edelbrock 2191 intake i am thinking about using the mopar purple shaft cam but i not sure which be the best for the street and power either the hydraulic 238 duration 474 lift are the 241 duration with the 484 lift i not sure what the advantage and the disvantage of either one would be can you please tell me which one i should go with and i am using a stall converter 2200-2800. thank you.

Depends on the LSA and duration@.050 on the intake. The lift wont affect driveability. The intake duration and the ,(LSA) the cam was ground on will affect low speed driveability. The wider LSA the better low speed street manners are. The narrower the LSA the higher the RPM band and peaky torque curve. If it were mine I would use the bigger stick, of course I like a lopey idle. This site has a lot of cam info, read down towards the bottom for LSA ,(Lobe seperation angle),explanation. http://www.webcamshafts.com/pages/cam_glossary.html this might help you make a decision. Ask Dave how he likes his new fast rate of lift solid bumpstick over his old hydraulic! Be aware if you have power brakes or even air conditioning, a smaller cam might be better for low speed cruising and keeping the engine from stalling with a lopey cam. Sorry, I dont know your combo, but these are things to consider. The cam with the smaller duration would probably match the stall rating of your convertor but Dave would know a perfect match in that regards for sure.

I used to use your bigger cam choice on the street.

In reality it is not much more powerful than the stock cam. But it was a good street cam.
You will need a 2800 stall converter and a little carb tuning to use it.

With a high mileage 440 burning a fair bit of oil and rather gay 3.23:1 rear gears, I ran high 14s on the strip with an otherwise pretty much stock weight Challenger.

280° Hydraulic: P4452993

Intake Duration, Nominal 280° Exhaust Duration, Nominal 280°
Intake Duration @ .050” 238° Exhaust Duration @ .050” 238°
Intake Lobe Centerline 106° ATDC Exhaust Lobe Centerline 114° BTDC
Lobe Separation Angle 110° Overlap 60°
Intake Opens 34° BTDC Exhaust Opens 74° BBDC
Intake Closes 66° ABDC Exhaust Closes 26° ATDC
Intake Lift .474" Exhaust Lift .474"
Note: as installed on 106° centerline per Chrysler


284° Hydraulic: P4120235

Intake Duration, Nominal 284° Exhaust Duration, Nominal 284°
Intake Duration @ .050” 241° Exhaust Duration @ .050” 241°
Intake Lobe Centerline 108° ATDC Exhaust Lobe Centerline 108° BTDC
Lobe Separation Angle 108° Overlap 68°
Intake Opens 34° BTDC Exhaust Opens 70° BBDC
Intake Closes 70° ABDC Exhaust Closes 34° ATDC
Intake Lift .484" Exhaust Lift .484"
Note: as installed on 108° centerline per Chrysler

Is the 2191 intake the Performer or Performer RPM? For the bigger cam I would opt for the RPM, it's got a little more plenum volume and larger runners. That '284' cam will have a nice lope to it. I think thats Drew's combo as well.

While on the subject of cam specs - Dave / Eddie, have you placed much faith in (good quality) vacuum gauges? I checked my 360 the other afternoon with a good vacuum gauge, now that i have it idling well with a nice new TQ.

At idle, with or without vac advance connected i was only getting 9-11 Inchs Hg. The normal range is specified up towards 18-22. I have made sure i have no leaks - i took the brake booster line off and sealed off that port and squirted WD-40 all around the carby base while running and no difference.

Connected the vacuum gauge first to the base of carby at the back, then at the vacuum takeoff on the dual plane manifold. Both gave the same readings.

SPECS of the Cam are Erson Hi-Flow Hydraulic, Advertised Rev range: 2700-5700, 0.472/0.472 lift, Duration at 0.050": 228, Advertised Duration: 296, Centreline 108 degrees, 0 advance.

We tried to dial in the cam at 3 or 4 degrees as Dave suggested early on, but it only seemed to fit properly at 0 deg.

So its a fair duration cam, old school technology. Would this be a big factor in the poor vacuum reading? The initial timing i have set at around 15deg. But can't drive the car until i sort out the damn leaky radiator.

The Vacum at idle Sounds about right for that big of a cam Steve. I have a Snap-On and a Harbor freight cheapy. Both are the same as far as accuracy. The SO is more durable and much heavier. It's also 10X the price

Connect your vacuum gauge again and monitor the rpm with something accurate too.

Then try turning your idle mixture screws a quarter turn lean.

If the rpm and vacuum increase keep going until you get a very slight drop in rpm and vacuum.

If the rpm and vacuum decreases when you go leaner then try going a quarter turn richer.
If going richer a quarter turn at a time makes the rpm and vacuum increase keep going until they stop increasing or start going down again.
Then back off lean until you get a very slight drop.

This will get your idle mixture spot on and your manifold vacuum as high as possible.

Also it is important that if you have an automatic that you do this with the car in Drive (and the brake on of course). Don't forget the car is in drive and then rev the engine like I did the other day. You get a fright doing that.

Again. With the car in drive you must make a note of the manifold vacuum. Use this figure to select the correct springs for the metering rods or Power Valve (Holley). Usuallly on the Holley you would rate the power valve at half the manifold vacuum. Can't remember how you do it on the Carter/TQ/Edelbrock. They have a chart or something.

If your RPM drops more than (Edited) 300 revs when placed in gear after setting it then you need a higher stall torque converter.

I don't know if this will help answer any cam selection questions but my (LA engine) 284/.484 purple shaft has been in service for quite a few years now and I'm happy with it. When I picked it out the 474 lift was available also, but seemed a little too small. IMO, this range is really pretty mild compaired too the solid lifter cams I ran in the past.

Also running a Holley 650 DP with a 8.5 Hg power valve and it seems to run crisp with no real bog above 1700 RPM. It is a clutch car though, a hard take off would be slipping it out in the 2-3 RPM range.

I haven't owned a big block motor but in the 340 this seems to be a very reasonable cam on the street. At idle the vacuum is about 13-14" which is plenty for the power brakes too.

Thanks Dave for that suggestion, i will do that soon! I havn't tweaked the new TQ at all since i have put it on. I will make sure every wheel is chocked if i put in drive! I think just from guessing that it does drop a touch more than 100rpm when engaging drive - i only got a 'More Stall' converter as this is my budget Challenger. They open up a standard converter and bend the vanes to get more stall. Only costs about $350, compared to around $900+ for a new converter and i had great success with my last one in a 340.

I might invest in an accurate test tacho too. As i complained in one of the posts here, the new electronic Rallye tacho i bought from Charger Specialties off Ebay, is of DUBIOUS accuracy. Looks factory though.

THanks Jon for advising of your 340 vacuum with that cam - if i can get mine up a bit from doing Dave's suggestions, it will be about right then.

Goldenblack440 wrote:I think just from guessing that it does drop a touch more than 100rpm when engaging drive

Sorry. I should have said 200rpm. Even a 300 rpm drop you can probably get away with but you will probably find you have to hold it hard on the brake to keep it standing.

I had the 284/484 cam in my 82 Cordoba drag car.(360cid) That car was soooo heavy. Completly stripped out with one racing seat that thing weighed 3400+ We me in it the race weight was 3600+

With 4.10's and 29X10.5 slicks the car went a best of 12.71 @ 106mph. I previously had the stock 340 cam in the engine. The new cam made a lot more power. I would think it would be even beter in a 440.

If you do the calculations the 360 was putting right around 330hp to the wheels. That's over 400 at the crank. Add 80 more cubes and you should be making decent power.

dave-r wrote: should have said 200rpm.

ok, that sounds better, the MoreStall is around 2700-2900 so should be right

burdar wrote:If you do the calculations the 360 was putting right around 330hp to the wheels. That's over 400 at the crank.

That's pretty decent figures - how much work had you done to the engine? Eg head work, Comp ratio, cast iron/alum heads, what intake/carb, headers, street exhaust? Thanks

Goldenblack440 wrote:

burdar wrote:If you do the calculations the 360 was putting right around 330hp to the wheels. That's over 400 at the crank.

That's pretty decent figures - how much work had you done to the engine? Eg head work, Comp ratio, cast iron/alum heads, what intake/carb, headers, street exhaust? Thanks

The engine was very mild.

The short block was a MP unit with 10 to 1 comp. It came with a 292/509 cam but I didn't think I wanted to spin the engine over 6500RPM. That is where that cam made its power.

I installed a Weiand windage tray and made a special plate that bolted in the valley area. MP used good magnum small block cores to make there LA short blocks so, the valley had 4 or 5 raised and tapped bosses that were there to bolt the magnums roller lifter follower to the block. I used those threaded holes to bolt the plate I made. The plate covered the big holes in the valley that are dirrectly over the cam. This forced the oil to drain back to the pan at the front and rear of the engine instead of draining onto the spinning camshaft. I read an article in a Mopar Magazine years ago that told about that. They said that at higher RPM you could possibly see up to 30 hp from that mod.

The heads were factory 1976 360 castings that I hand ported. I gasket matched the intake and exhaust ports and smoothed the pushrod hump in the intake runners. I kept the stock 1.88in and 1.60ex valve sizes. I could have seen more high RPM power by going to the 2.02in valves but the engine was built on limited funds.

The intake was a Weiand X-cellerator single-plane. I ran a 750cfm thermoquad so I used an adapter in the intake. There was a slight mismatch between the intake and the adapter but I had to get the engine together so I left it alone. The headers were cheap FlowTech's with 1 5/8 primaries. I didn't run the car on the street so there was no other exhaust on the car. I did run 10" to 12" pipes off of the collectors. It is an old racers trick to paint the collector extensions. You make a few passes and see where the paint has burned off. Where the paint starts to be visable is where you cut off the extension.

Trans was a 904 with a Trans-Go TF-2 shift kit. I installed a new "manual valve" in the trans so the convertor would fill in PARK. The conv. was a Hughes 10" 3500 stall unit.

I foot braked to 2500RPM on the start. I let the trans shift on its own. First to second and second to third shifts were at 6100RPM and I went through the lights at 5800RPM. It seemed to runout of steem at the top end. That is were the 2.02 intake valves would have come in. For what I had into it I was happy.

hey Burdar, thanks for all that description. If you're as slow a typer as me it would have taken a while. There are a few similarities between that engine and mine. Except mine is in a heavy Challenger so i wouldn't get near that time. You didn't say what rear end you had but i'd guess 3.55? Mine is 3.23 as its a street car. I also have those standard valve heads and have done more or less exactly what you did to them. I am running the same TQ but on a Edel dual plane as i wanted more low down grunt. I am running a 1" spacer and Ceramic TTi 1 and 5/8 headers but with an 'X' pipe between twin 2 &1/2 exhaust. I also have a 904 with deep pan and a TCI valve body. (have you heard any bad things about TCI stuff? It was a budget car so i got that cheap). Cam is Erson 472/472/228 ADV: 290.

My oiling system stops at a HV pump - not as special as yours - amazing that so much HP can be picked up from not having oil drip onto the cam. So they say... i can believe windage on a crank, but windage on a cam, would that cause so much drag on the engine?

Also, have you heard about resin filling the block 50% for increased HP? it stiffens the block up tremendously and is done before boring and line boring etc. Releases a lot of HP, just like chassis stiffening does as well. And as you would realise from looking into the bottom of a block through the open core plugs, all that crud, there is a lot of dead water at the bottom that sits there and doesn't circulate much anyway, so 50% resin filling does not affect cooling too much.

When my mechanic built my 440 it had a lot of expense put into it, Brodix heads with 2.225 valves, Forged pistons, H beam rods, blueprinted and balanced etc, but i was a little annoyed that he didn't resin fill it for me, especially as it is a very very early 440 (1965) out of an Imperial and according to 440 Source, these early castings were not as strong as the later post-70 blocks.

I ran an 8 3/4 rear with 4.10's and a spool with 29x10.5" slicks. The year before I put 4.10's in it I was running 3.23's and a 235-60-15 drag radial. My best time that year was a 13.55 @ 98mph. What does your Challenger weigh? The Cordoba was 3400+ stripped. A Challenger is probablly that heavy with the interior still in it. I always thought that if I put my 360 into a light A-body that I could be very close to the 11's.

You probably know more about filling a block than I do. I always wondered if there would be cooling problems. What about the added weight of the fill on the front end?

My 440 Challenger is a lot lighter than stock from the cowl forward but still weighs 3800lbs with a dry fuel tank. with my 180lbs and a tank of fuel it's race weight is about 4000lbs.

Like was said before, filling a block is an old racers trick. A guy I know was a pre-funnycar/funnycar crew chief back in the '60s and he said that they used to use toothpaste as a filler. though they completely filled the water jackets as they were running nitro (alcohol during the nitro ban) and had no cooling system. The toothpaste could be flushed if the block needed to be worked on and then refilled. He also said some guys would put in some concrete instead (especially front-engined dragsters) if they needed some weight towards the front of the car.

Not sure what toothpaste would have done, but they must have gotten some benefit from it. At least it could be flushed out when desired (and if they used flouride toothpaste, the engine might have less cavities, ha ha.) But resin filling is used to stiffen the whole bottom end. Concrete would go some way to doing this, but the high specific gravity of resin as well as its ability to get completely into every crevice when liquid is why its used. Concrete would have trouble doing this. Then you risk getting airpockets which heat up and cool down, causing all sorts of hot spots and trouble.

I'm sure it would only add around 15pound max to the weight. It also reduces thermal expansion of the bottom end, i don't really know a hell of a lot about it, but the effect on cooling efficiency is quite low compared to the benefits. Mopar Action magazine did a great article on it - i will try and hunt that up and post it on here.