what are my cam options

Started by tr8todd, December 18, 2010, 08:09:44 PM

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tr8todd

I am getting ready to order a couple of camshafts for two different 4.0 engines.  First engine has had a previous performance build by the car's previous owner.  Not sure what he was thinking, but he used a 215 long snout cam, no cam retainer, a Buick cover and harmonic balancer.  Any surprise that the cam gear was wiped out?  This engine also sported roller rockers which pushed out way too much oil that inevitably found it's way down the valves and into the combustion chamber.  It spewed grey smoke and had a nasty wet sooted exhaust.  PO tried to fit valve seals, but they didn't help.  For this motor, I'll probably just order a 215 type cam and machine the end to accept a cam retainer.  Probably ditch the rollers as well.  Not sure what to do with the second 4.0.  I want to use the 4.0 cover with the crank driven oil pump, and no distributor.  The 4.0 camshafts have a much shorter nose.  Where do I source an aftermarket cam for this set up?  I've only seen the early style cams with the longer nose to drive the distributor.  If nobody has this short nose cam blank, should I send out the stock cam for a regrind or order an early style and machine the end to simulate the later shorter nose?  Anybody use this later cover with a performance cam?  The cover I have looks like the early ones.  It has the distributor hole and retaining bolt boss, but they were not machined out.  I think it came out of a 97 Rover.

roverman

Todd, sounds like you want hyd./flat tappet ? Edelbrock ? Real Steel ? Sell those "pesky" roller rockers ? Hyd. roller would be Paul Menten. Believe it or not, early style cams worked well for their application,(non racing). The lobes are ground tapered, in opposite directions, to counter thrust action. In theory, the distributor resistance to turning applies some thrust towards block.This all goes awry, when taper wears on lobes or when lifter load on lobes is insufficient, to hold cam in postion. Good Luck, roverman.

tr8todd

Back when I raced the TR8, I would routinely wipe out cam gears and front cam bearings.  Once the cam retainer was installed, those problems went away.  It was easy to tell when the cam gear was on the way out.  At higher RPMs, the engine would loose power because the timing would be off.  I'm still not sure where to look for the stock style short nose camshaft.  I have to have one ground for the turbo FI 4.0 I'm working on.  I want to retain the entire front cover set up.  Plan is to install the cam with a conventional 4 barrel for break in purposes and then later install all of the turbo/FI pieces.  I don't want to risk the cam trying to get all of this techno stuff sorted out.  I'm sure it's going to be a challenge.

MGBV8

Carl