Should I upgrade my Camshaft? • The Dodge Challenger Message Board

by **R/T Rick** » 25 Sep 2007 3:34

Now that I got my car up and running again since the freak oil pick up tube incident

I would like to change out the original nylon gear timing gear and chain. With that said it is not too much more trouble to pull the intake and camshaft. I am running a 440+6 with 4speed and 4.10 Gears what cam choice would be good for this combo? Looking for nice street/strip nothing radical but will pull to 6500 :mrgreen:

. Also what are the specs on my stock cam? Thanks in advance, Rick

by **dave-r** » 25 Sep 2007 13:48

Your stock 440 six pack cam has the following spec.

Advertised (seat to seat) Duration = 268 in./284ex.

Duration @ 0.050 lift = 208in./221ex.

Valve lift (1.5:1 ratio rockers) 0.450" in./0.458"ex.

by **dave-r** » 25 Sep 2007 13:51

Get a good quality Australian made timing set. A few of my friends have found the "American made" (but are they?) timing sets can be quite a way off on the timing.

by **dave-r** » 25 Sep 2007 14:02

Hughes Engines HEH1928BL (or BL3) cam would be a direct replacement with a noticeably more power slightly higher up the rpm range which suits your gears better. You could go bigger but you will start to need ported heads and adjustable rockers.

219/228 duration @ 50thou and 0.489"/0.524" valve lift. This is 10 degrees more duration than stock.

Other makes of cam may produce similar results. It is just that I have the data on these cams and have used them myself with good results.

This one should make another 40hp with no other changes but you will be using the power more because it is more where your gears are making the engine work.

Make sure you match the timing set and cam as you can get one bolt or three bolt versions of both. Three bolts are better.

Some re-tuning of the carb idle system may be required.

by **R/T Rick** » 25 Sep 2007 17:39

Thanks Dave, You think I should just leave it alone? It does run and pull hard the way it is. I know she would probably wake up with something hotter and I am tempted.

by **dave-r** » 25 Sep 2007 18:12

I don't like the original mopar cams. They were designed 40 years ago now so they are not exactly state of the art. :roll:

I think you would benifit from a modern fast rate of lift cam as long as it was about the same duration or slightly more.

One the same duration wil give you a bit more power if it has a faster rate of lift and a bit more lift.

I picked one with a bit more duration because you are using 4.10:1 rear gears. The extra duration will put the power more where you are actually using it. Between 3000 and 6000rpm. Pointless having lots of torque at 2000rpm because with those gears you are hardly moving any speed at all.

Any bigger and your stock heads will not flow enough.

So if it were me I would change the cam. You don't even have to worry about stall speed changes with a 4-speed. :wink:

The only thing is you might need more air at idle. So some tweaking of the carbs may be required.

by **Eddie** » 25 Sep 2007 18:22

R/T Rick. Are you keeping your stock exhaust and rocker arms(non-adjustable)? Also you should know that your heads will need to have the valve spring seats cut if you decide to use dual springs which some cams dictate so be advised about that. Stock 906 heads have single spring with damper. Also whichever camshaft company you use, ask them the minimum lifter diameter requirements of that lobe design. Hughes engines FRL,(fast rate of lift cams), must use a .904 lifter diameter, this is an advantage. Dave is correct, the MoPar cams are ancient, they will get the job done but there are better designs. Comp Cams makes fast rate of lift cams as well. :thumbsup:

by **R/T Rick** » 25 Sep 2007 18:43

Do I have to specify "fast rate of lift"? or is that what the cams are automatically? I am keeping stock exhaust and manifolds. OK I am convinced to swap the cam, so what all will I need? (part numbers, parts, etc....) I do not want to pull the heads and have anything done in that department. Keep that in mind please. Thanks Rick

by **Eddie** » 25 Sep 2007 19:04

R/T Rick, thanks for the additional info. So I assume you dont want to use exhaust tubing headers as well? In that case, Daves recommendations are hard to beat. This will work well with your stock exhaust, and new valve springs to match the cam. Rick to find if the camshaft is Fast Rate of lift, simply take the duration@.050 and divide it by the total duration: Example 290 total duration divided by 245@.050=84% rate of lift. A 85% rate of lift is considered fast rate of lift. All MoPar Perf. cams are 85% Hughes are even better as are other companies such as Comp Cams which make MoPar specific cams which take advantage of our .904 lifter diameter. Dave gave you the part number to the Hughes which is HEH 1928 .489/.524 and 219/228@.050 I would also use Dave Hughes valvesprings. You'll need an on the head spring compressor and fitting for your heads to use an air line,(to keep the valves on their seats as you remove the valve springs and retainers, keepers and locks). RollMaster and Pro-Form makes billet timing sets available from Mancini, Hughes ect.. As Dave stated make sure to get a three bolt or whatever the cam snout is drilled and tapped for, Hughes will set you straight on that.

by **Eddie** » 25 Sep 2007 20:07

Rick I would use the cam, springs, retainers, keepers, locks, 3 bolt if the cam is also, one bolt is OK too! timing set,(billet or machined), all as a matched set. This way those parts are compatible with each other and there wont be any late night frantic visits to the NAPA store. Comp Cams calls this their K-Kit, Hughes will set you up with a matched set as well. Good Luck and let us know if we can further assist you. Eddie :thumbsup:

by **dave-r** » 25 Sep 2007 20:33

Sorry I forgot to tell you that you need a matching set of springs for the cam. The Hughes Engines ones are single springs and I don't think there will be any problems with fitting them.

An old trick for replacing valve springs without removing the head is to run a length of thin rope into the cylinder through the spark plug hole and then turn the engine by hand to bring the piston up towards TDC until it squashes the rope against the valve. This will hold the valves firmly in place while you change the springs. Hughes engines sell a tool where you can compress the spring without access to the other face of the head.

by **Eddie** » 25 Sep 2007 20:39

Good cheap way to do it Dave! Just dont drop a valve into the cylinder. It WILL ruin his weekend. No joke.(dont ask me how I know that either) :mrgreen:

by **R/T Rick** » 25 Sep 2007 20:55

Thanks a bunch guys, I am definately looking into the hughes cam. Your positive this will work nice for my set up? I'm putting all my trust and confidence in you guys :roll:

lol just kidding. I agree, it sounds like a good set up. Should run like a raped ape :mrgreen:

by **Eddie** » 25 Sep 2007 21:17

The most important thing will be the break-in period, ask Dave Hughes what he recommends in that regard.(Probably his Racing oil and his supplement), with your new lifters and cam lobes wear mating in that critical 20 minutes of initial start up. A bit of advice. Make sure your engine starts easy like fresh plugs cap rotor ect. You want the engine to start up right away with little cranking time, then rev to at least 2000+RPM's and hold it there, dont let it idle. And yes, it will pull harder especially as you exceed 3k RPM's! You may or may not need any carb work. We'll see. :thumbsup: