TR4/4A Engine upgrades from a TR4a - what to get?

[TR4nut]

I thought I read an earlier thread on this, but I haven't had luck searching. I am potentially 'upgrading' my TR4 using stock 4a parts. So far I've amassed an exhaust manifold, SU intake setup, cylinder head, and distributor. Should I be grabbing the camshaft too? Anything else?

I have a small window of opportunity with a 4a parts car in my area which I think will close shortly. I don't want to miss out on the obvious parts while they are available.

Thanks,
Randy
65 TR4

 

[Brosky]

Randy,

I, personally, would never swap a used cam from one engine to another. Or a crank for that matter, unless some machine shop work was done to the block and the crank, as in line bore. If you are getting the cam reground and then possibly block work, it would be fine.

The other external parts are no problem, except for having the head pressure tested, cooked out and possibly resurfaced.

JMHO, other may have varying opinions.

 

[jessebogan]

Good thing to grab from a 4A parts car is the wiper switch. Same as the headlamp sw in a TR4 ,and no longer available.

 

[Banjo]

Randy, best would be to grab the whole motor as one lump. then you have everything.
I second the used cam/crank remarks.
But I think with the head, and both manifolds you've got most of the 4A advantages.

 

[TR4nut]

Thanks for the replies - I wanted to avoid grabbing the whole engine as it added some issues on how I was going to haul it to my place as well as explain the parts to my spouse. The manifolds I can hide under the bed..

Randy

 

[70herald]

The manifolds I can hide under the bed..

Randy

Just get one of those antique beds with really tall legs and a skirt to hide the your stash /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif

 

[piman]

Hello Randy,

"other may have varying opinions"

I would have no worries about transferring a camshaft, if it is in good condition and is better than the existing one. Make sure that the followers are good also and keep them in order, i.e that they go back onto the same lobes.

Alec

 

[TR4nut]

I have heard differing opinions on swapping used camshafts,but I thought the TR4 block was pretty robust in that department. I didn't think the stock TR4A cam was substantially different than a TR4 cam to warrant the change but it would be nice to have a spare handy.

But it does bring up another question I've pondered: how does one determine if the cam bearings are bad in a TR4? I've used plastigage on big end bearings to check clearance, etc, but that won't work for the cam - do you check for play with a dial indicator to determine wear on the bearings? Seems I recall that these bearings are pretty stout and rarely require replacement, but that could be wrong.

Randy

 

[Bugeye58]

I'd use a bore gauge and a micrometer.
Jeff

 

[TR3driver]

For the front bearing (which is most likely to wear since it carries the most load), you can just try to wiggle the camshaft with the timing chain removed. Otherwise, I'd use a telescoping hole gauge and a micrometer (or calipers in a pinch). But note that you have to be very careful to get them perpendicular to the axis, or you'll get a false reading. Best practice is to take several measurements at each point, and measure multiple points within the bearing.

 

[TR3driver]

Also, if the parts are cheap, you might well be able to sell the head, crank and cam for enough to buy a performance regrind for your old cam /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

 

[Got_All_4]

Swapping used cams should not be a problem if you ether use new tappets or carefully keep and match up the exact tappets from the engine that the cam came out of. I'd opt for the new ones to establish a new wear pattern. In ether case use a cam brake in lube. Your most expensive option is getting those new light weight and hard tappets that are made out of the same material the space shuttle tiles are made of. Only $50 each. You can swap in and out as many new or used cams you want.