340 Cam Compatability

[MOPARJ]

I have folks telling me that an XE274 is too radical for a stock 70 340 with close to stock or stock converter and 3:23 gears. I know im giving up some bottom end from the stock stick, but im looking for a rougher, choppier idle. I have no power brakes or steering. Any suggestions or imput?

 

[abdywgn]

What is duration at .050"?
I ran the MP 284/484 cam with 3.23 gears installed at 108 degrees in a 340.
This is the recommended cam for an auto,so since I figured it would make a
little low end,it was used with a 4-spd.This cam has more duration so if you
are using a stock 340 convertor,I'd think you'd be okay.You can always degree
it go move the power down a little bit.Be sure to use a dual plane intake,the
single plane I tried didn't start the power till 3500 with that cam.Bob

 

[moper]

It will be too much. I would stay away from the Xe series, or similar fast rate cams if you want the sound. But they will be down on torque with 3.23s that will be felt when you drive it. Personally, I cant imagine buying a cam strictly for sound. But that's just me. There are also some newer cams that tout that "oldschool" (poor) idle characteristic too. So I would shop around.

 

[dgc333]

I am running the XE268H in my 360 and the idle is smooth and it pulls hard from 1500-6500 rpm.

I'm with moper, why would you purposely want a cam that makes the engine run poorly on the bottom end if you aren't going to make the other changes necessary to take advantage of the additional top end power?

 

[388dart]

I have folks telling me that an XE274 is too radical for a stock 70 340 with close to stock or stock converter and 3:23 gears. I know im giving up some bottom end from the stock stick, but im looking for a rougher, choppier idle. I have no power brakes or steering. Any suggestions or imput?

Try this one :
Camshaft Specification Table
Part Number 20-309-4
Engine 1964-2000 Chrysler
273ci-360ci
8cyl.
Grind Number CRS 268AH-10
Description

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Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.464 0.464
Duration At 0.006 Tappet Lift 268 276

--------------------------------------------------------------------------------

Valve Timing At 0.006
Open Close
Intake 28 60
Exhaust 72 24

--------------------------------------------------------------------------------

These Specs Are For The Cam Installed At 106 Intake CL
Intake Exhaust
Duration At 0.05 222 226
Lobe Lift 0.309 0.309
Lobe Separation 110

--------------------------------------------------------------------------------

Recommended Valve Springs 901-16

has a good lumpy sound and will work great in your application.

 

[lead69]

The xe seiries of cams are designed to build low end while retaining the top end horsepower of a similar duration cam,they also make alot more vaccum than a similar advertised cam.In short they make great cams for the street compared to a similar duration old school design and imo that grind should work great in a 340.The only thing that would hold you back is if your running stock manifolds-you probaly would be o.k. with the convertor but I wouldnt run it with manifolds.Aside from that cam you can have a powerful idle with a smaller cam that performs good at lower rpms if you go with a lower duration and a tighter lobe seperation,say a [email protected] and a 108ls 104cl,such as an old school isky 264 mega cam I believe it was.

 

[moper]

I know im giving up some bottom end from the stock stick, but im looking for a rougher, choppier idle.

I like the XE line, but they idle better, not worse, for similar sized older grinds. Maybe you should listen on the Comp site to some idle sound bytes. See what your definition of "choppy" is. I dont think the XE268 is a great cam. but it should have a fairly stable idle quality...Very little chop to me...

 

[D-mailman]

The xe seiries of cams are designed to build low end while retaining the top end horsepower of a similar duration cam,they also make alot more vaccum than a similar advertised cam.In short they make great cams for the street compared to a similar duration old school design and imo that grind should work great in a 340.The only thing that would hold you back is if your running stock manifolds-you probaly would be o.k. with the convertor but I wouldnt run it with manifolds.Aside from that cam you can have a powerful idle with a smaller cam that performs good at lower rpms if you go with a lower duration and a tighter lobe seperation,say a [email protected] and a 108ls 104cl,such as an old school isky 264 mega cam I believe it was.

What he said........