cam upgrade for stock 360 with low Comp Ratio

[Slantsix64]

Wanted to upgraded my camshaft thats in a stock 360 1985 its got low compression ratio i know that will have alot to do with my selection. i will runn a 600 cfm carb and headers along with a lbd4 eddy intake. its a street car it will be going into a b body with 3.21 gears

 

[MOPAROFFICIAL]

Wanted to upgraded my camshaft thats in a stock 360 1985 its got low compression ratio i know that will have alot to do with my selection. i will runn a 600 cfm carb and headers along with a lbd4 eddy intake. its a street car it will be going into a b body with 3.21 gears

If the motor is out and you have to pull the front cover, intake, valve covers, rockers etc....just pull the heads and have them decked .040. That will decrease the chamber volume by around 9cc's and bring you into a larger selection of cams. Jmo

 

[stroked340]

My friend has had good luck running the Comp cam CCA-20-223-3 .477 in/.480 ex in his smog 318 with aluminum intake 625 carb and headers..

 

[318willrun]

heads (or should I say good sealing valves) are where power and gas mileage are at. I agree with the post above, cut them .040 and I'd do a valve job. Then, for a cam I'd get somewhere between .450-.477 lift, and between 208*-224* @50

 

[ir3333]

if you are just going to change the cam i would stick with a short duration and
about .450 lift...a modern grind like comp. xe256 or similar.
For strictly street light to street light the old generic .204 / .214 .429 / .444
will start pulling at 800 rpm and pull hard to 4800 and be very inexpensive but
hard on tires!

 

[rumblefish360]

My friend has had good luck running the Comp cam CCA-20-223-3 .477 in/.480 ex in his smog 318 with aluminum intake 625 carb and headers..

Absolutely the largest cam I would run with what you got. I suggest one smaller. A cam with 218@.050 intake duration is IMO a better fit. You can use it with the stock converter. Been there done that.

XE262;
Hydraulic flat tappet
Basic Operating RPM Range:1,300-5,600
Duration at 050 inch Lift:218 int./224 exh.
Advertised Duration:262 int./270 exh.
Valve Lift0.462 in./0.470 in.
Lobe Separation (degrees):110
Grind Number:CRS XE262H-10
Valve Springs Required:Yes

Lunati, Crane cams, Summit etc... have similar cams.

With the beginning 1300 rpm range, Just a few rpm's over idle, it is within the stock converters ability to cope without issue. By the 5600 rpm mark, you should be flyin!

 

[Slantsix64]

If the motor is out and you have to pull the front cover, intake, valve covers, rockers etc....just pull the heads and have them decked .040. That will decrease the chamber volume by around 9cc's and bring you into a larger selection of cams. Jmo

When Shaving the heads 0.40 will i need to shave anything off the intake or it will bolt right on

 

[rumblefish360]

Maybe.....

 

[MOPAROFFICIAL]

When Shaving the heads 0.40 will i need to shave anything off the intake or it will bolt right on

Maybe.....

Like rumble said.

The head gaskets get thicker when replaced, factory .019'ish thick gaskets are traded for 8553 pt felpro that are around .046 compressed. You really only see around a 3cc cc chamber reduction if you go with that gasket, or about .4 and the intake spread isn't narrowed enough to necessitate milling the intake side or actual intake face " which ever your preference".fwiw
Reuse the factory with copper coat and you'll probably need to mill the intake face.
The formula for 340/360 chambers is .0048 per cc, for every .0048 milled from deck, you mill .0095 from intake side, be it intake face of head... or intake itself.
Sometimes you don't need to mill , lets use this case ....... cutting .040 chamber side and so therefore then cutting " .076 intake face"..... The formula will get a .060 thick "typical performance intake gasket" in there, but if you consider various intake gasket thicknesses.... mill say .046 intake face and then use a .030 felpro MS 90109 that's .030 and now your intake fits fine.
Ways to get it done 101...

 

[Abodybomber]

Absolutely the largest cam I would run with what you got. I suggest one smaller. A cam with 218@.050 intake duration is IMO a better fit. You can use it with the stock converter. Been there done that.

XE262;
Hydraulic flat tappet
Basic Operating RPM Range:1,300-5,600
Duration at 050 inch Lift:218 int./224 exh.
Advertised Duration:262 int./270 exh.
Valve Lift0.462 in./0.470 in.
Lobe Separation (degrees):110
Grind Number:CRS XE262H-10
Valve Springs Required:Yes

Lunati, Crane cams, Summit etc... have similar cams.

With the beginning 1300 rpm range, Just a few rpm's over idle, it is within the stock converters ability to cope without issue. By the 5600 rpm mark, you should be flyin!

Perfect choice, Robert..... I,Would personal run a non air gap RPM,to keep fuel atomized...It helps streetability with lower compression builds...It sounds wacky,but it works.

 

[rumblefish360]

I've run the AG for a loooooong time now. It just takes a few minutes when it's cold outside to warm up. JUST like a Big Block! If it is really chilly out, the choke keeps coming back on.
Annoying!

Old weather drivers should be so equipped like the OE set you up as. Choke stove, full air cleaner go a long way in winter.

 

[Abodybomber]

I've run the AG for a loooooong time now. It just takes a few minutes when it's cold outside to warm up. JUST like a Big Block! If it is really chilly out, the choke keeps coming back on.
Annoying!

Old weather drivers should be so equipped like the OE set you up as. Choke stove, full air cleaner go a long way in winter.

Agreed

 

[nm9stheham]

The formula for 340/360 chambers is .0048 per cc, for every .0048 milled from deck, you mill .0095 from intake side, be it intake face of head... or intake itself.

I suspect a typo above..... IIRC, you are supposed to mill .0095" from the intake side for every .010" from the deck or main head surface.

And no reason to not use the 1121G head gasket IMHO. .028" thick compressed. Just a few less cc's in the chamber to rob compression....

Be ready to use the RTV at the ends of the intake rather than the original type gaskets. Not any big deal.

 

[318willrun]

When Shaving the heads 0.40 will i need to shave anything off the intake or it will bolt right on

I never had to do anything with the intake when cutting heads .040.

 

[rumblefish360]

I never had to do anything with the intake when cutting heads .040.

Good to know. I hope his are also stone fresh uncut units.

 

[Lelo Dart]

Voodoo Hydraulic Flat Tappet Cam & Lifter Kit - Chrysler 273-360 250/256 - Lunati Power

Cam Spec Card :: Lunati Power

 

[RustyRatRod]

The Hughes Whiplash cams are designed 100% for what you have. Low compression and even stock valve springs. Although I would draw the line at using stock valve springs.

 

[Slantsix64]

Absolutely the largest cam I would run with what you got. I suggest one smaller. A cam with 218@.050 intake duration is IMO a better fit. You can use it with the stock converter. Been there done that.

XE262;
Hydraulic flat tappet
Basic Operating RPM Range:1,300-5,600
Duration at 050 inch Lift:218 int./224 exh.
Advertised Duration:262 int./270 exh.
Valve Lift0.462 in./0.470 in.
Lobe Separation (degrees):110
Grind Number:CRS XE262H-10
Valve Springs Required:Yes

Lunati, Crane cams, Summit etc... have similar cams.

With the beginning 1300 rpm range, Just a few rpm's over idle, it is within the stock converters ability to cope without issue. By the 5600 rpm mark, you should be flyin!

Will this cam work well with a lbd4 intake? i will be using a lbd4 intake 600 cfm carb along with headders and milling 0.40 off the heads with this cam would this be a good combo?

 

[Slantsix64]

Good to know. I hope his are also stone fresh uncut units.

yes its a stock 360 with 20,000 out of a day car van. i was considering changing the stock valve springs should i here is what i found. COMP Cams Xtreme Energy Cam and Lifter Kits K20-222-3

 

[rumblefish360]

Will this cam work well with a lbd4 intake? i will be using a lbd4 intake 600 cfm carb along with headders and milling 0.40 off the heads with this cam would this be a good combo?

What cam? The one below in the next post? Your kidding right? I just listed that as a recommendation to you!

OK, I'll be simple and answer it in 2 words!

HELL YA!

yes its a stock 360 with 20,000 out of a day car van. i was considering changing the stock valve springs should i here is what i found. COMP Cams Xtreme Energy Cam and Lifter Kits K20-222-3

I like the whole kit package. Everything and probably more than you need. Don't forget the gaskets!!!!
Watch the head gasket thickness. N sense killing the head down and installing thick gasket!

I think you'll like the combo. It provides good power. With 3.21's or greater gear, you should get into the 14's without to many problems.

 

[Slantsix64]

What cam? The one below in the next post? Your kidding right? I just listed that as a recommendation to you!

OK, I'll be simple and answer it in 2 words!

HELL YA!




I like the whole kit package. Everything and probably more than you need. Don't forget the gaskets!!!!
Watch the head gasket thickness. N sense killing the head down and installing thick gasket!

I think you'll like the combo. It provides good power. With 3.21's or greater gear, you should get into the 14's without to many problems.

okay good whats a good thin head gasket i could use?. i also forgot to add i going to install this engine in a 1970 satellite b body for my brother who's been busy in the police academy.

 

[Slantsix64]

0.20 thickness Mopar Performance Steel Shim Head Gasket Sets P4286754

 

[toolmanmike]

0.20 thickness Mopar Performance Steel Shim Head Gasket Sets P4286754

Big block. The steel shim small block gaskets haven't been made for years.

 

[nm9stheham]

Try Mr Gasket 1121G

 

[nm9stheham]

FWIW....With the 1121G gasket, a .040" head mill, and stock pistons .110" in the hole and 4.5 cc dish, that SCR works out to 8.4/8.5. DCR with that cam will be at 7.15 or so at an installed ICL of 106.....I would not hesitate to bump it another couple degrees advance.