Author Topic: 440 Cam Selection Advice (Read 6935 times)

magoo426 · « **on:** October 13, 2014 - 08:55:07 PM »

Hello. I have a 1968 440, 906 factory heads right now with 10:1 compression. I have a Hurst TKO-600 5-Speed manual conversion kit, with 3.73 rear end. I don't plan on drag racing this car, just for street performance and fun.

I'm considering getting Edelbrock's 84cc RPM Heads and RPM Dual plane intake. I know some like Stealth heads. But lets imagine I go with the Edelbrock heads and intake I mention. I've heard members like Lunati cams and they perform better then the Edelbrock designs. So I emailed them for recommendations on cams based on my proposed set up with the aluminum heads.

They recommended this cam:

�Advertised Duration (Int/Exh): 268/276
�Duration @ .050 (Int/Exh): 226/234
�Gross Valve Lift (Int/Exh): .494/.513
�LSA/ICL: 110/106
�Valve Lash (Int/Exh): Hyd/Hyd
�RPM Range: 1800-6200
�Includes: Cam & Lifters (#71977PR-16)

Can some members give me some advice and guidance on this?
Thanks for your help.

edl94 · « **Reply #1 on:** October 13, 2014 - 09:24:19 PM »

The cam specs you listed are a #10230703 cam. I have a very similar setup and run that cam. 10 to 1, stealth heads, holley street dominator. I am very happy with the cam it has a nice lope and power throughout the RPM range. I run it with an auto and mild converter. I think it is a great choice.

Chryco Psycho · « **Reply #2 on:** October 13, 2014 - 09:27:17 PM »

Sounds like a good choice if you want to be in that rpm range .
Personally I would use Stealth heads more bang for the $$ & the Street Dominator intake will offer better hood clearance

magoo426 · « **Reply #3 on:** October 14, 2014 - 05:28:37 PM »

Thanks for the advice guys. I understand the Stealth Heads are about 1/2 what the Edelbrock RPM Heads are, but I'm concerned about the quality of the heads. I've heard a few people not have very much luck and needed extra work to correct their issues as received. This was some time ago and maybe their quality has improved since then. Have you guys had issues with their heads before? Your support of their heads has got me thinking so I'm not against them, just considering all options.

edl94 · « **Reply #4 on:** October 14, 2014 - 09:31:05 PM »

I was concerned about quality also. It appears they had some problems when they first came out, but they have worked them out. mine work great and I am very happy with them.

magoo426 · « **Reply #5 on:** October 14, 2014 - 10:22:25 PM »

Did you have any work done to the heads (new springs, valves, etc) replaced on them? Or did you just take them right out of the box and bolt them on? Have you ever dynoed your engine? I'm curious what it made for HP/TQ. What else can you tell me about your setup (headers, valve train, etc)?

Chryco Psycho · « **Reply #6 on:** October 14, 2014 - 11:32:12 PM »

I would swap out the retainers & locks & use 10* but otherwise the 440 Source heads are good

magoo426 · « **Reply #7 on:** October 16, 2014 - 05:33:42 PM »

Chryco Psycho, I know this is getting away from the cam question I asked earlier, but the guy I bought the engine kept the stock connecting rods and used Keith Black pistons with the following specs.

KB Performance Pistons#648-KB237.030
Chrysler 440ci Hypereutectic Pistons �Flat Top
�4.350'' Bore (+.030'')
�Use w/6.768'' Connecting Rod & 3.750'' Crank Stroke

If I currently have a 10:1 compression with the stock 906 heads. Would I be able to still put on the Stealth Heads and be ok without hitting valves and my compression? I'm thinking my compression would climb to around 10.5:1 or so.

Does this sound ok? Sorry for all the questions, I'm not a detailed engine guy. I got some basic understanding, but I'm still learning about them.

Chryco Psycho · « **Reply #8 on:** October 17, 2014 - 09:25:53 PM »

As long as you have valve reliefs in the pistons you should be OK But you still need to measure clearance .
With alum heads the heat loss is greater so the effective compression will be a point lower so it will act more like 9.5:1

1 Wild R/T · « **Reply #9 on:** January 01, 2015 - 01:25:06 AM »

Quote from: magoo426 on October 16, 2014 - 05:33:42 PM

Chryco Psycho, I know this is getting away from the cam question I asked earlier, but the guy I bought the engine kept the stock connecting rods and used Keith Black pistons with the following specs.

KB Performance Pistons#648-KB237.030
Chrysler 440ci Hypereutectic Pistons �Flat Top
�4.350'' Bore (+.030'')
�Use w/6.768'' Connecting Rod & 3.750'' Crank Stroke

If I currently have a 10:1 compression with the stock 906 heads. Would I be able to still put on the Stealth Heads and be ok without hitting valves and my compression? I'm thinking my compression would climb to around 10.5:1 or so.

Does this sound ok? Sorry for all the questions, I'm not a detailed engine guy. I got some basic understanding, but I'm still learning about them.

Excellent piston choice, 2.067 compression height, flat top with 5cc valve pockets... As mentioned the Stealths or Eddies would both work well with your short block..

magoo426 · « **Reply #10 on:** January 01, 2015 - 09:41:01 AM »

My plans have changed. I'm going to keep the 906 iron heads. Taking the advice of many on here to have realistic expectations for output. So I decided to keep the 906 heads and try to get the horsepower around 450 if possible. 1 Wild R/T, I'm trying to understand your post. Do you think the piston selection is not the best for this? It looked like judging from your response that it had a little bit of sarcasm but I wasn't sure and just wanted to ask. Plus if you have better advice for piston selection, then I'm all ears.

Thanks for everyone's help.

Chryco Psycho · « **Reply #11 on:** January 01, 2015 - 10:29:48 AM »

I would not do that , 906 are an emission head with zero quench , it will cost as much to to rebuild the iron heads as buy new stealth heads

1 Wild R/T · « **Reply #12 on:** January 01, 2015 - 12:35:00 PM »

Quote from: magoo426 on January 01, 2015 - 09:41:01 AM

My plans have changed. I'm going to keep the 906 iron heads. Taking the advice of many on here to have realistic expectations for output. So I decided to keep the 906 heads and try to get the horsepower around 450 if possible. 1 Wild R/T, I'm trying to understand your post. Do you think the piston selection is not the best for this? It looked like judging from your response that it had a little bit of sarcasm but I wasn't sure and just wanted to ask. Plus if you have better advice for piston selection, then I'm all ears.

Thanks for everyone's help.

The dangers of sarcasm & the internet... All to often I'm sarcastic & people don't read it that way but in this post I'm completely serious, so often guys choose a piston that's so far in the hole you need to send a search party to find it but that 2.067 is a good number...

On the other subject I 100% agree with Chryco Psyco lose those 906 heads...

I get the impression the short block is assembled & if thats the case disregard this suggestion but if it isn't I would deck the block to 10.710... That would zero deck the pistons & give you .040 quench....

magoo426 · « **Reply #13 on:** January 01, 2015 - 08:56:29 PM »

Hi 1 Wild R/T. No problems here. I just wasn't sure and I didn't want to make a situation worse and I appreciate your input. I'm no expert on the engine side and try not to sound like I am either. Yes the engine is completely re-built and assembled. It's a 1968 engine I bought for $2000 off a guy who didn't want the engine anymore and had never installed it in a car either. I had an old 318 before and every engine that I looked at before was not rebuilt and I didn't want to spend money on a block that I wasn't sure if it was good or not. So I went this route where I got all the receipts that he had from the machine shop that magna-fluxed it, bored it 30 over, etc.

I've read one guy dyno'd a 440 magnum and started swapping basic performance parts out and re-dyno tested the engine. I'm trying to get something close to what he did. I copied his data and plotted it out on a graph. Hopefully it attaches ok to this post. Realistically I don't think I'll get as good of results he got but, maybe I can get within 25~50 HP/TQ of them. I'm planning on swapping out the intake, adding headers, and potentially using the same cam he did, my current cam is one cam below what he used.

1 Wild R/T · « **Reply #14 on:** January 02, 2015 - 02:38:13 AM »

Ok, I did the math, assuming the pistons are .015 in the hole which is probably close, could be higher... With the 906 heads you have a true 9.42 C/R With Stealths it calculates to 10.19 C/R & with Edelbrocks 9.92....

If you do aftermarket heads you should have no problem getting more out of your engine than those dyno numbers...

1-7/8 headers, Hookers/Thorleys/TTI's what ever fits your budget/needs...

850 Holley, Quick Fuel, Proform, BG.. All good choices

Depending on your body style I prefer the Edelbrock Performer RPM though the SD is a good intake, just not as responsive/snappy down low...

Plenty of good cam choices, for good street manners stay under 235ish @ .050

Author Topic: 440 Cam Selection Advice (Read 6935 times)

magoo426

440 Cam Selection Advice

edl94

Re: 440 Cam Selection Advice

Chryco Psycho

Re: 440 Cam Selection Advice

magoo426

Re: 440 Cam Selection Advice

edl94

Re: 440 Cam Selection Advice

magoo426

Re: 440 Cam Selection Advice

Chryco Psycho

Re: 440 Cam Selection Advice

magoo426

Re: 440 Cam Selection Advice

Chryco Psycho

Re: 440 Cam Selection Advice

1 Wild R/T

Re: 440 Cam Selection Advice

magoo426

Re: 440 Cam Selection Advice

Chryco Psycho

Re: 440 Cam Selection Advice

1 Wild R/T

Re: 440 Cam Selection Advice

magoo426

Re: 440 Cam Selection Advice

1 Wild R/T

Re: 440 Cam Selection Advice