360 build-need help.

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63dartman

63dartman

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I am putting together my roller 360 and I would like to know how bad it would be to run the original stock 1989 360 cam with my build. It would save me some cash for other parts if the performance hit is not too bad. I am building a 360 roller with kb107 pistons zero decked., scat rods, compression will be 10.1:1. EQ magnum heads, performer rpm air gap intake, doug's headers, 904 tranny w/shift kit. 8 3/4 suregrip with 3.23 gears. Strictly a street car that may see a few passes at the local strip.Any help would be much appreciated.
 
I was really looking for more along the lines of how much performance loss will there be between the stock cam and maybe a roller performance cam matched to my build.
 
In a word, a lot!

IF your not ready to purchase a roller, then a new cam should be put in as a "For now" and not a used cam. The stock cam is really small to use with that high of a ratio. Install a Hyd. cam with similar specs as the roller you want.
 
x2 with rumblefish.

If your just going to put in the stock 89 cam, why even bother doing the build?
 
The stock 89 cam is a roller cam. It just isn't what you would call a performance cam. Thanks for the help though. I guess I should just save a little more and get what is needed the first time around. I could really use some help with cam selection. Any reccomendations for a good performance street cam that will live with the restrictions of the magnum valve springs? I think max lift is right at .500
 
I forget what those heads will take for a max lift. Perhaps one of the been there and done that guys can answer.
 
I dont think you can. That cam is made to develop cylinder pressure with 7.5:1 pistons. You have 10:1. You have to put a performance cam in it. But, you dont necessarilly have to be a roller. A flat tappet cam would be fine.
 
If I go with flat tappet (I won't though)what would I do about the lifters? My block is for roller lifters. I thought they were different from the la blocks?
 
you can use flat tappet cams in a roller block.....the roller block just make is easier and cheaper to use hydraulic roller lifters.

i have a MP 360 factory short block in my Duster, it is a roller block...it came from MP with a hydraulic flat tappet cam in it...
 
63dartman said:
If I go with flat tappet (I won't though)what would I do about the lifters? My block is for roller lifters. I thought they were different from the la blocks?
Click to expand...

Like 70aarcuda and myself as well with the MP create short block. Roller block, Hyd. lifters (W/a 292/.509 Hyd. purple cam.)

The difference between Magnum and "LA" blocks are lack of oil passages to feed the rockers for the "LA" engines and where the motor mounts are. Late model "LA" roller engines and some (If not all) Magnum engines have dual provisions for motor mounts.

Everything else swaps over. You'll be fine.

Back to the cam question for the moment. What cam are you looking at/thinking about?
 
ok, now I'm really confused:) I thought I had an 89 block but it looks like a 92 by the block stamp. My stamp is 53006921-360 or is the 92 in the stamp not the date code and only part of the ID?

1989-92 360
5.9
4.00
V-8 Roller Tappets

As far as cams go I was looking at maybe this one. Why does it say springs required? Will I need to change mine if the cam does not exceed my springs max lift?

COMP Cams
Manufacturer's Part Number
20-745-9
COMP Cams Xtreme Energy Camshafts
Summit Racing Part Number
CCA-20-745-
Hydraulic roller tappet
Basic Operating RPM Range
1,000-5,000
Intake Duration at 050 inch Lift
212
Exhaust Duration at 050 inch Lift
218
Duration at 050 inch Lift
212 int./218 exh.
Advertised Intake Duration
264
Advertised Exhaust Duration
270
Advertised Duration
264 int./270 exh.
Intake Valve Lift with Factory Rocker Arm Ratio
0.480 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio
.480 in.
Valve Lift with Factory Rocker Arm Ratio

0.480 int./0.480 exh.
Lobe Separation (degrees)
114
Computer-Controlled Compatible
Yes
Grind Number
CRS XR 264R-12
Valve Springs Required
Yes
 
It could be required since there not in the kit but for certainly new valve springs to match the cam you have in order to control the valves best vs. the stockers which have an unknown amount of abuse (Not so much as mileage) and pressure (Ability to control the valve properly) is the reason it says required.

IMO, a good move to get them.
 
OH, PS like the cam.
I used a similar Hyd. cam before. Very nice with the gears you have. No converter required.
 
The heads I am running have less than 5k on them. They are clearWater EQ Ram heads completely stock from Clearwater. I don't know the limitations on the springs though. I do know that they claim to be a thicker casting that prevents the tipical cracks found in the used magnum heads. Do you think the springs I have will support this cam?
 
Call/E-mail them direct for info. They'll tell you.
 
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