chaoz28

i have a 72 "010" casting 350 i want to do a build but i dont have the cash to do the bottom end aside from reconditioning. on top is what i already have to put on.

procomp 210 runner 64cc aluminum heads
dominator manifold
1.5 rollers
a 650 double pumper
i have headers
gear drive

i was wondering if id be pushing it putting an xe268h in its what i have n my daily driver but that had flat top pistons. if the xe is too big for this build what shoudl i step down to

82Five-O

either go for that cam or summits SUM-K1104 cam. I've run both and both match your stall and component combo.

chaoz28

well i forgot to mention its going into a street rod backed by a t-5 so stall isnt a matter

Apeiron

The XE268 is a weenie little cam for huge 210cc heads.

chaoz28

even with the 1.5 rockers?

Apeiron

1.5 rockers are stock, it's not an improvement.

chaoz28

hmm well this is making me want to change out the cam in my bird too. what should i go to id like to stay with comp i can get them for less than others

Apeiron

What are you trying to accomplish with the engine? Why those enormous heads?

Atilla the Fun

and does your 350 have flattops or dished pistons? flattops means you're around 10.2:1. In which case, I'd say an XE274 and a 4-something axle ratio.

chaoz28

the engine im building is going into a 32 chevy coup. its got 3.55 posi from an old 70's camaro although the 3.55s were thrown in after. i want the car to hit into the 13's but for teh most part its going to become my new daily driver whle i stroke and charge my firebird. the heads are going on it cuz i already have them laying around from an old build that went stray. the block has stock dished pistons 4 valve reliefs

Sonix

iTrader: (1)

210cc heads on a light vehicle like that are going to be WEIRD. Daily driver is not the first thought to pop into my head!
Shrink the heads, or make it your drag car. It'll be very lame at the bottom end. Cam the crap out of it to make it work. I'd look at an xs282 or whatever the 280ish solid flat cam is.

chaoz28

what about the thumpr series cams?

Apeiron

A good choice if you care about sound and not performance.

chaoz28

hmm no i think ill pass there then lol.. what about a magnum cam from comp ive heard good things about them

Sonix

iTrader: (1)

they're ok. They're a straight pattern cam though. They work pretty good with aftermarket heads with good exhaust ports. So it would work ok for you.
Remember, a low RPM cam would be a mismatch, so you need to CAM IT UP.
I'd highly recommend a solid roller.

Why do you use a gear drive by the way?

chaoz28

same as the heads. its an unused gear drive that is just collecting dust so i may as well throw it n. i dont care if its whiny or not.

Sonix

iTrader: (1)

i'd be more concerned with spark scatter...
I'd leave the gear drive on the shelf, or sell it... just get a summit/cloyes/whatever double roller chain for $40

chaoz28

never heard of spark scatter fill me in?

Sonix

iTrader: (1)

There's no cushion with a gear drive, to chain to take up the slack, the vibration. It will shake the distributor (it's driven by the cam, which is now rigidly coupled to the crank, which takes all kinds of abuse..) and can cause spark scatter. poor spark at high RPM.
Gear drives are like dual carbs these days. More flash (and sound), less usefulness.

chaoz28

that makes complete sense. ill go with a double roller then. but this may be off subject but how worthy are belt drives then?

Apeiron

Spark scatter isn't poor high-RPM spark, it's variability in timing due to slack in the distributor train. It's not a problem particular to gear drives, it happens with chain drives as well.

Belt drives are just way too expensive.

Sonix

iTrader: (1)

What's the problem with gear drives then, aside from noise? Am I using the wrong terminology? I thought it can cause distributor problems, due to excess torsional vibration?

Apeiron

Noise is the biggest thing. Some people talk about valvetrain harmonics with gear drives, but chain setups have valvetrain harmonics too, just different ones.

chaoz28

well my main question is, would it kill me to use the gear drive. id much rather spend the 40 bucks on a decent coil than on another timing drive if i dont have to