Ok, guys, I need a little education on cams, specifically for the 230 flathead 6 I'm putting together for my '50 plymouth. Here's what I have so far for the engine:

Edmunds dual water heated intake, with a pair of Holley/Weber carbs
Split factory exhaust manifold, dual exhaust with crossover
Edgy finned aluminum head, 9:1 compression ratio
The block is a 218, but I am going to replace the crank and rods with those from a 230, and bore it 40 or 60 over.

So now I want to have the cam reground for a little more performance to go along with the rest. I plan to drive the car daily, and on road trips now and then to rod runs, so I don't want to get too radical, and sacrifice drivability/economy. I want it to sound cool, look cool, and run better than it did as a 218.

Earl Edgerton of Edgy Cams recommended an RV type cam regrind, with a duration of 260 and .409 lift. He says it will have a smooth idle and good low end power. These numbers mean little to me, as I know little about cams and the subtlies of their design.

What do you think would be best for this engine and the type of driving I plan to do?

Thanks for any advice you may have.

Pete
http://home.rmci.net/blueskies/plymouth.html

Couldn't advise you on that, but I'd be willing to trust what Edgarton is telling you. He seems to know his stuff.
How much is he going to charge you for the camshaft? I have a spare camshaft that I was thinking of sending to him, but I'm not sure if it would be regrindable, since I think it's a regrind (to stock specs) already.

I guess my remark in the other post about you needing a rebore, is a moot point if you're planning to go 60 over. Keep in mind though, that 60 over is not going to add a huge amount to your displacement number, maybe 3 CI or so.
All the other stuff you're doing is where you'll gain the most. I can't wait to hear how it comes out.

That would be about the equivalent of an old 3/4 race grind. Back in the old days there were only about teo or maybe three grinds for each engine. 3/4 race ( whatever that means ) was the smallest, then full race, and then track grind. All would be fairly tame today except for the track grind which would be pretty "rumpy". A 260 deg. solid lifter cam would be about right for a street engine and would probably even pick up the low end torque a little. Stock cams are very mild. It might have a slight exhaust note. More like the when you start to slip the clutch and load the engine a little than a rough idle. The duration in degrees is what makes or breaks the low end torque. A lot of guys just talk about cams in regard to lift, but it's the duration that's important. The more duration you have, the more valve overlap ( when both valves are open at the same time ) you have. The reversion caused by this requires more rpm to overcome causing a loss in low end torque.

[This message has been edited by DEL (edited 02-14-2002).]

Thanks for the reply Del-
I'm having my engine shop do the valve train for me, including the cam. They are going to send out the cam for the regrind. They calc'd the engine rpm at 65 mph based on the tire dia., the rear ratio, and the overdrive reduction, and said they would try to optimize the cam for torque and horsepower for hyway cruizing, taking into account the 9:1 head, dual intake and exhaust, and 230 bored 40 over. I don't know yet what this means for the cam, but I imagine it will end up to be something like the 3/4 grind you mentioned in your post.

Anything else I should know about or do while putting this back together? This is the first flathead I've done, so I'm a bit green here. I've read pro's and con's about changing the oil filtration, etc, so I'd planned to keep it basically stock asside from the mods I've already mentioned. I also read in the inliners tech tips that aluminum heads should be torqued the second time after the engine has cooled back to room temp rather than while hot. Is this the case?

Thanks again, Pete

Just curious, are you going to 12v electrics on your plymouth?

I'm still running stock CR on my dodge, and I'm about ready to give up on originality, and switch over to 12 volt. I'm pretty sure if I up my compression ratio any, that old 6 volt starter wouldn't be up to the job.
What's your plan so far?

Carlo-

I bought a wire kit from EZ wiring, and I'm going to rewire the entire car. A 21 circuit kit is only $211 with shipping. Compare that to Ron Francis and others, and its close to half. So I'll have a full fuse block for all the stuff on the car. Also will be switching to 12v negative ground, so I'll have to fabricate a bracket for the alternator to sit where the old generator was. I'm keeping the original guages, so I'll have to reduce back to 6v for them. I had my radio worked over by Bob's Radio and TV, so I don't have to worry about the positive ground issue. I've heard that running the 6v starter on 12v is not a problem since it only runs for a few seconds at a time and the windings are pretty stout. I'm not sure if my old starter has much life left anyway, so I may look for a 12v unit. Any idea what year the factory switched to 12v?

Pete

12v came into use in 1956. My old 6v works fine on 12v.

Jim R

I put a group 1 8 volt batt in my 1946 WD-15, and the starter cranks great at subfreezing temps. The headlights are LOTS better than my stock PT Cruiser. I burn out a sealed beam about every two years. I figure it's worth it. No other mods to the VR, etc.

A 230 MOPAR build from 2002

I noticed the beautiful Slant 6 (SL6) rocker arms shown in picture 15 of 31 and wondering if they could be adapted to a 302 GMC?
I am looking for higher lift rockers with a ratio of 1.6 or 1.7. They do not exist.
What is the lift ratio for the SL6?
What are the key dimensions for the SL6 rockers? ie push rod center to main shaft center and main shaft center to valve stem center.
Does anyone make roller rockers for the SL6?
Does this idea make sense?

The 302 rockers are much larger than the /6