440 Question

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DodgeFreak

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hey i'm getting a demon thats semi set up for strip. I've got a 75 440 police motor i'm going to drop that in the demon and run it till i get a 400 stroker motor built...my question is heads and cam and compression...I've got a Cranecam grind number H302-2 Int. @ Valves .504 Exh. 528 . I'm guessing my motors only 9.5:1 compression...i dont' want to tear the bottom end apart because its been rebuilt 2000 miles ago..i need\want compression around 10:1 with that cam..can i mill the heads enough to get it up there?? I'm thinking about running a set of closed chambered 383 heads and mill them and run bigger valves..what should i do?? how fast should the demon be with the 440 in the 1\8 and 1\4?? at what speed thanks..jsut tring toget an idea of what i'll be running..
 
Any Idea what pistons are in the motor ? You may not beable to mill that much off the heads to get 10:1

Whats the duration @.050" of the cam ?
Intake, carb, converter stall speed and gearing ?
 
Part Number: 684561 Grind Number: H-302-2 (REPLACES CCH-302-2)
Engine Identification:
Start Yr. End Yr. Make Cyl Description
1970 1978 PLYMOUTH-DODGE-CHRYSLER 8 ROUGH IDLE, PERFORMANCE USAGE, GOOD MID-RANGE HP, MILD BRACKET RACING, AUTO TRANS W/3000+ CONVERTER, 3800-4200 CRUISE RPM, 10.0 TO 11.5 COMPRESSION RATIO ADVISED. BASIC RPM 3000-6500
Engine Size Configuration
383-440 C.I. V

Valve Setting: Intake .000 Exhaust .000 HOT

Lift: Intake @Cam 3360 @Valve 504 All Lifts are based
on zero lash and theoretical rocker arm ratios.
Exhaust @ Cam 3520 @Valve 528
Rocker Arm Ratio 1.5

Cam Timing: TAPPET @.0044
Lift: Opens Closes ADV Duration
Intake 39 BTDC 83 ABDC 302 °
Exhaust 88 BBDC 44 ATDC 312 °

Spring Requirements: Triple Dual Outer Inner
Part Number 99893
Loads Closed 120 LBS @ 1.875 or 1 7/8
Open 315 LBS @ 1.372
Recommended RPM range with matching components
Minimum RPM 3000
Maximum RPM 6500
Valve Float 6500

Cam Timing: TAPPET @.050
Lift: Opens Closes Max Lift Duration
Intake 9 BTDC 43 ABDC 107 232 °
Exhaust 58 BBDC 4 ATDC 117 242 °

Thats the specs on the cam...
Don't know what the pistons are..i haven't tore the heads off yet i didn't rebuild the motor my self so i don't know whats inside i just know that its been rebuilt and the guy i bought it off of is a good friend...Intake i'm not sure what to run as with the carb..i've heard dominator intake and a 850-950 carb probably going holly dp. and stall will be a stock stall because i'm going to try and run rhodes lifters and gearing i was thinkin 3:55s
 
You really need to know what pistons you have to get a true compression answer. As far as that cam, I havent run the new grind, but the old 302 is awesome, and will run quite well with less compression than the listing..I've run it with as low as 8.5:1. I used a 2200 convertor, and it was a little light in that range, I'd say 2500-2800 would be great for street use. You'll get the most bang for the least buck with a good 5 angle valve job(cutters, no stones), and back cut or new valves, and a basic bowl blend and gasket match. Any more, and you're putting $$ into one thing that should be going to the bigger engine IMO.
:joker:
 
I bet you've got a set of old TRW l2266fs in the holes. they are the worse pistons for compression and way a tom but seem to get used all the tim.

That being said, My old 440 had those in it, the heads were milled a ton (the open chamber was almost a closed chamber) and I used thin gaskets. Compression was maybe 9.5:1

The cam was an isky 292, 243 @.050" .503" lift.

It made enough power to puch my heavy 70 Cuda in to the mid 12s.
 
How much did you mill the heads on your motor??.. also has anyone ran the new 302 cam?? think it will be tomuch?? how can you tell what pistons you have?? do you have to tear it clear down or can you tell just by lookin at the tops??
 
The heads were milled when I bought the car. they were atleast shaved .060"

The pistons I had,had the part number stamped right in the top.
 
did you have your pistons out or was it on the top or inside of the piston??
 
its hard to say if they are stock or not. Are they flat tops ? valve reliefs or not ? Is there anything stamped in to the tops ?
 
Yep I agree you gotta know what pistons are in it and the deck height. Just know way to be sure without checking. Ron
 
well the problem is i still have the motor in a truck and i need to pull it out befoer i pull the heads (still sorta using the truck for wood) i was just hoping i could get a ball park figure...thanks i'll post back when i get the heads off..
 
How much can and should you mill a set of 452's on a stock 71 440, with out milling the intake? I am doing a cheap hotrod valiant just to keep me from messing with my cuda. I want to selp port the heads with the DC template when I find one. What kind of compression do you think I will end up with? Thanks.
 
when you mill the heads, they will mill the intake side of the heads and then you won't have to mill the intake

(this is what i've been told, so don't take that as concrete fact)
 
IIRC, it's .009 off the intake fro every .010 off the deck surface. Usually, you can get away with up to .020 or so without interfering with the bolt hole alignment. You can enlarge the holes in the intake for more, but basically, you are making the ports misalign at the same time. You can only mill the intake side of the heads about .040, because you are thinning the valve cover gasket area/attaching hole area. So, the answer is, you can mill what ever you want, but you have to fix the alignment one way or another. Also, the more you mill, the worse your pushrods will fit. So, if you mill a lot, you need to check and may have to repair or replace a few things. Sometimes doing it "cheap and easy" isnt. The last time I did something like that, it cost around $225 just for milling, because of the # of passes and setup that is needed to cut heads and intake. The add rocker shaft shims, pushrods, springs(for the new cam), gaskets, and time, and it went to over $600..and the intake and heads are a package now, you cant just swap it out, or sell it later(honestly), without the heads. :bounce:
 
What's the max lift you can run before hitting the valves to the piston, without valve releifs?
The 528 might be a bit close.
I know my 383 had these very slight marks on them from the 509 cam. It dd have a bit of valve float though due to a bad set of springs
 
I have a .528 Mp in my 440.."516" heads milled .100", and stell gaskets, with stock '70 440 flattops...If they hit, I havent noticed..lol. (alright, this one I didnt check pistons to valve..I should have, and I would if I were doing it again..I might even do it when it comes out, just to see how close they are...lol)
 
If you think this engine will perform well with out milling the heads then i won't mill them at all...i haven't decided on if i was going to use this cam or not..or sell it and help fund for another cam...also...How do you check piston to valve clearence??
 
If it were me, and I was already expecting to pay for milling, then I'd do it..You're not hurting anything by milling modest amounts. I'd have .030 taken off the deck and intake surfaces. The cam will work fine, and that should bering you up around a true 9:1., maybe a tiny bit more.
 
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