cam change

mopops

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1989 360 La roller motor from van, 8-1 compression in 82 mirada 904 trans 373 gears . what cam can i go with to wake this up-no piston change. tks
 

Duke5A

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That compression is going to severely limit your options. A thin head gasket and a pair of 63cc closed chamber aluminum heads can raise that compression a 1.5 points. I'm not sure any cam change without also increasing squeeze is going to be worth the time and expenditure.

Are you wanting to keep it a roller cam? After flattening two cams I'll never go flat tappet again.
 

Duke5A

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If you're not willing to change heads, then at least think about swapping to a thinner head gasket. Without more squeeze any hotter cam is going to sacrifice low end torque.

I'm sure AJ will chime in. Builds like this are his wheelhouse.
 

mopops

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all stock with fresh rebuild ,has RV cam now ,holly 4bbl edlebrock intake. car runs real well,so i don't want to get back in the motor n iam too old for that-cam change is about as much as i want to do
 

AJ/FormS

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1989 360 La roller motor from van, 8-1 compression in 82 mirada 904 trans 373 gears . what cam can i go with to wake this up-no piston change. tks

You said 1989 360LA roller.
If it is truly an LA, then it was never born a roller, and the Compression ratio would have been down around 8/1, as you say. While it is possible to retrofit a roller into an LA, that change alone by virtue of the long clearance ramps on a hydraulic roller, with no other changes, usually drops the effective compression ratio into the "doggy at take-off" zone, that requires both a higher stall TC and performance rear gears; which you already have.


If it was born a roller cam engine, then it would be a 5.9Magnum, and would have been a 9.2 to 9.4 engine

The answer to your question is completely different for either engine.
And so, I would highly recommend that you
do a compression test AND
post up the specs of whatever cam is currently in it; AND
state the flash-stall of your current TC.

And then, since you say;
car runs real well
What are you expecting from a cam-change?
 
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M_Body_Coupe

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So stock roller (non-Magnum) cam is the starting point, right?

OK, what are the usable RPM ranges you have in mind?

You're got decent gears already, nothing crazy, but it'll let the motor pick up the RPM faster, even if it's a little lazy due to lack of static CR.

How about something like Lunati 20200217 (50417) 1500 - 5200 RPM, .470"/.489" lift, 206/215 @0.050", 258/268 adv dur. 112/108 LSA/ICL, with a description of:

"Smooth idle. Good cam for factory re-placement with excellent low end and mid range torque and horsepower that requires minor upgrades to the factory computer."

You do not have a computer to worry about I think, so that frees you up a little bit.

Beyond this you might want to take a look at their Voodoo grinds, pretty nice stuff.
 

Remow2112

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See if Hughes engines or comp cams makes a whiplash or thump'r cam in roller. The idle is a little goofy but they pull like crazy down low. Other wise you really want a rv / towing cam that is more designed to give you grunt down low and not care about about high rpms. (IE. not reving the motor to 6k rpm)

Jealous of your roller. We ran one of those in my brother's Duster for racing and had the stock cam reground. Worked great till he blew a shifter and stuck all the lifters and spun a bearing.

Dan...
 

mopops

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tks still shopping for my winter job , lots of mid to late 80sLa blocks are set up for rollers
 
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AJ/FormS

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1989 360 La roller motor from van, 8-1 compression in 82 mirada 904 trans 373 gears . what cam can i go with to wake this up-no piston change. tks
With No Other Changes, you cannot wake up the bottom end with a bigger same type cam, that has a later Ica. The later Ica drops pressure every single time no exceptions. Less pressure means less power.
What you wanna do is what the manual-trans guys do, which is slip the clutch to a higher rpm where the power is.
Have a look at this and you'll see what I mean;
power-318.gif

Say you currently have a TC with a 1600rpm stall. On this graph, that is 80 horsepowr.
Suppose you installed a 2800TC and found ~155 hp.
There is no other thing you can do to your engine with an automatic, that can touch a 75 hp increase at zero mph, short of supercharging it.
Once you have a decent TC in it then we can talk cams.
 

mopops

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thanks for the input ,a new higher TC is probably were i want to go,motor already has reground performance RV cam now( no specs on it) tks geo
 
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