273 cam suggestions

well heres a vid of the mopar '759' cam in my 11:1 318....

[ame="http://www.youtube.com/watch?v=e7l0iJQNMC8"]YouTube - ‪Crackin up Hairy Canary‬‏[/ame]

sure it sound better in real life, vids cant capture the real note, then crammed on into the digital highway...

mopar '759' a hydrolic 110LS nice non offensive easy driver, LA small blocks are gifted with .904' lifters, great for solids advantage over hydro, even though hydro's will sound lumpyer, though the duration specs would be great solid for 273 at 107LS, obviously ramps would be different, (hydros run contour/wider down ramps stop valve float)

will see if can find some footage of running in my 63 Val 318 many years ago, had 108LS +5 deg advance, duration 50' -in 228/ex 232 -Advertised in 292/ex 288 (crow cam) extremely responsive great 60ft times, pull the 3.23 diff to high speeds 220kph,

CUDA from memory you say youre running the 302 closed chamber heads? with some high comp tektic pistons? if you have got your quench right she'll be a beast, if you below deck you may not get away with flame front detonation as standard Chrysler open chamber will...

hune said:

if you got a static 10.5:1 comp thats some nice pistons, no matter if you had .038 gasket, advance youre cam up on install at least +4... ("+6 even") being 110 lobe sep on 273 you want to get youre torque band come in pushing A full body, specially if auto' obviously 318-360 are more forgiving (107-108 ls good for drag accel launch), once off the line she will have some sting, good for open street/track race day, and sound like a track car not a harleyLOL (as mine does) and she'll drink 98octane ;)

if using standard valve train (that you should) get d moly -.100'retainers so can fit the spring in without bind and scallop rockers so they dont hit (and reposition oil galley''), you may get away with LT1/chevy brown spring for this too??, unless you are hitting over 7000rpm on reg basis, do doubles!

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hune,

Thanks for the tips, I was not sure what to set the cam for advance. I need to take a look at my springs again, I think they are chevy springs though.

I have no clue what "scallop rocker" means so I am all ears.

4-speed car, it came with 3.23 but I have a set of 4.10 that will get installed for now.

the 318 is as follows...
-87 truck shortblock W/78k decked .055 (stock cast pistons are at zero deck)
-new rings, stock 78k bearings and oil pump (looked NEW government engine)
-Cloyes double roller
-mopar '759' cam/lifters (0* advanced/retarded)
-smith brothers pushrods
-heavily ported/tapered 87 #302 heads
-70's cast iron spreadbore smog intake
-holley 600cfm 4160
-stock manifolds
-2.5" single exhaust
-recurved dizzy with mopar orange box

Lke I said, put my Cuda at 14.6@97 with a 2.5 second 60' and pegleg 3.23's just wondering if its too much cam for a low compression 273 with stock #302 heads and some work done to the manifolds or headers?

Cudaguy,
Sorry for the hijack just got a little excited. You got a great running 318 and I wish I knew more about your "stock" compression 273. Have you pulled the heads off the 273 and measured how far down the hole the pistons are? 120psi compression is at the service limit so if it were me I would want more with any cam.

You could zero deck the block / shave the heads a little and then you would not have regrets after the fact.

As far as cam choice, that cam you have in the 318 worked great and it should in a similar built 273 but compression will be a factor.

I am not a cam guru, just offering my opinion / advice based upon my mistakes.

well, to be honest, if Im gonna pull the whole engine, I will most likely just put the whole 318 in it....at this point its not worth putting the machine work into (have another 273 to build for the Cuda...main focus is the Cuda really and getting this Valiant a solid driver)

The plan was having the 318 on a stand for more headwork, a freshining up, more cam, bigger valves, etc. at that point I might as well just deal with only having 320hp and gather parts to build it

Cuda, dynamic comp of 120psi is low for 8.5:1 static comp, was this with the 759 hydro cam? if your not running the 273 solid rocker gear the 759 cam
P4452759 .430"/.450" lift, 260/268 duration advertise? (not too big in my opinion unless that's @.050") 110 deg LS and apparently 2+ degree advance ground in, is not a bad option if you dial lots of advance start at+6 even +8, this will bring up your cylinder pressure to around 145psi,

if you skim your 302 heads too much the swirl idea is out the window, you could deck the block but sounds like your pistons are around 0.100" below deck, don't know if a 273 is happy with that much decking, upside you'll be lighter ;)

ideal would be if KB made 273 high comp pistons? then use 273 orig valve train, sit down with some master grind lists, and 'as one of the last parts to buy!' choose drivable lumpy that if set right should have no drama for 14's


and Rbob, "scallop rocker" is 'if you running 273 rockers with -.100" retainers to fit up to .500" lift cams with no spring bind without having to grind the base spring valve boss' is removing material on the rocker were the retainer will hit, bench grinder/ linisher, other trick is weld top oil hole and redrill were you scalloped in direction to the valve tip''''

you have a good high comp combo, noticed your lift is .501" so this will work but dont think the LT1/chevy brown springs will cut it, I went double springs after my head guru asked if I was racing, these chevy springs cant handle Chryslers fast cam ramp ability at high revs that .904" lifters can offer, apparently metallurgy/metal structure wear/soften out spring seat pressure quickly,

but dont think the LT1/chevy brown springs will cut it, I went double springs after my head guru asked if I was racing, these chevy springs cant handle Chryslers fast cam ramp ability at high revs that .904" lifters can offer, apparently metallurgy/metal structure wear/soften out spring seat pressure quickly,

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Depends on the manufacturer of the spring as well as intended purpose. Lifter diameter has nothing to do with it and ramp speed/rate opf lift I should say have everything to do with it.

904 v 842 diameter has effect on cam lobe geometry, hence to tech Chrysler does not have to use chevy master grind patterns (olden days but still happens)

you are right would not be surprised if LT1 and chevy brown springs are now re-manufactured offshore like china.. cut production costs as that is happening in au. Or bad quality control/metal blend e.t.c.

for intended purpose LA engines have the ability for 7000rpm using own internals reliably, agree not an advisable spring really with a reasonably stove hot engine

rumble rollers are the ****! but thats aloda coin for a 273, unless a real bad boy engine.

273 valve train sort of gift to LA engines set good it works within its limits (lift/lobe profiles) pince with roller? ;), after that roller is good specially with new **** oil regs,

have not used but is brad penn oil still going in the states? old school refinery have heard... any good oil for flat tappets over there?

First and foremost, watch the words you right. The MOD job I do may get in the way of the spiced words your currently, freely making use of.

Second, I'm not arguing about roller lifters, direct what you think is the argument to the one arguing that point and re-read what I wrote. Otherwise, your just having a bad case of diarrhea of the mouth from the mush brain sysndrome.

The 273 valve train, when new, wasn't accurate, but IMO, better than the Hyd. stock though not as good as the aftermarket rockers. Being so, there a OK upgrade over the Hyd. rockers for cheap. Key word, or better yet, phrase, "On the Cheap."

have not used but is brad penn oil still going in the states? old school refinery have heard... any good oil for flat tappets over there? / but thats aloda coin / pince / after that roller is good specially with new oil regs / agree not an advisable spring really with a

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HUH?
Not fully following your English, keep in mind that your local tounges dialect is getting in the way some, not to mention dropped words from sentences. This mention is not to start an issue.

Oil's? Brad Penn is here.

no dramas rumble, will try and watch my literature

keep in mind we cant read and write down under

chairs,
hune ;)

Hune,

Thanks again for the advice. Still need to look at my springs, may just get the ones recommended by the cam mfg.

Hughes Whiplash.