Changing Horses in Mid Stream....

[Guest]

The machine shop that built my head installed the valves and springs. I have the head in another machine shop that will be testing the springs for pressure and binding. All should be good, unless there might have been too much spring pressure. Will find out this week.

 

[Opa]

keep us posted Bill,feel bad for ya and all, but this might be a learning curve for everybody else considering performance upgrades.
I had my cam reground to very similar specs as GP3.by an outfit in Vancouver B.C. called Shadbolt cams, they also resufaced and hardened the lifters at that time.They used a grind that Colt cams in Langley B.C. still uses today as Geoff Bardal was an employee at Shadbolt.Specs for the cam are listed on his web site (Colt Cams) under British Cars -TR6 performance cam. It is quite lopey and a bit of a pain in slow traffic where the RPM drops below about 15-1600.It also has a noticeable lope at idle which is around 1000-1100. It does make up for it after 2500 RPM tho.

That'S part of the reason I put a switch on second gear for the overdrive.Gives a little more range of RPM.I have also not installed an aluminum flywheel yet but may try one if and when the clutch needs attention. I'm thinking this could further affect low speed driveability.

The other problem I have is to meet smog test numbers at idle. Run tests are good. The only way I get it thru is to retard timing and set idle speed to about 1500 rpm,add methyl hydrate to the fuel tank and a can of Pennzoil emissions reducer.
Good Luck!

 

[Brosky]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]By all means, check with whoever you trust, Paul. I'm just repeating what I've heard from the likes of Kas Kastner and Greg Solow.[/QUOTE]

Randall, somehow we always seem to agree to disagree amicably, which is a good thing. And I never meant to imply that I didn't trust your judgment, which I think you know. In this case however, I have to bow to your comments and acknowledge your statements as more correct than mine. In speaking to several cam manufacturers, the cams are not "fully hardened" in the production process, nor should they be (as I was incorrectly assuming). A good cam is in the RC52-55 range. The problem is that to test them, ruins the surface that you are testing. While none would readily state the break in process contributes to a "work hardening" of the cam lobe surface, there was enough of your answer to be correct over what I had thought was the correct process. There answers seem to confirm that the lobe surfaces are considered polished and that the parts mate together as the break in.

An interesting point was that everyone points to the oil (lack of zinc) as an issue, but they are also very concerned about the use of hardened lifters in the RC65 and up range. Several felt that these are too hard and combined with the very slippery oils in use today, which do not allow the lifter to rotate on a flat tappet cam, an increase in lobe wear will be inevitable, sooner, rather than later in most cases.

As Bill mentioned, the correct valve spring pressure and the angles created a higher lift all contribute to a more accelerated wear situation than on a softer stock grind.

So again, I'm pretty much back where I started from. I think that it's a crap shoot no matter who you chose or what you end up doing, even if you match everything and do your due diligence about oil, additives and valve springs.

 

[TR3driver]

On another note, what are the chances of my being able to inspect the rod and crank bearings on my engine with the engine in placed.

It occurs to me that I misread this question the first time ... it's not hard at all to pull & inspect the rod bearings with the engine still in the car. You'll need to drop the pan (which I assume you've already done) to inspect/change the bearings, and pull the head if you want to inspect the pistons (they only come out the top).

Not sure of the details for main bearings on a TR6; but they are reasonably easy on a TR2-4. Last time I did it, the front & rear caps were a little stubborn, so I made a simple puller from some bar stock and 4 bolts. The gasket between the front sealing cap and the front plate will tear, so replace it with your favorite "form a gasket" goop.

 

[Guest]

In dentistry, we deal with some similar problems. There is something called the "envelope of function" where anterior (front) teeth work top against bottom in an elongated oval when functioning and each person is similar/different. If one violates this envelope by encroaching upon the function area, disaster. Such as when "cosmetic" dentists lengthen teeth with porcelain veneers or even crowns that the patient's muscle memory, bite and TM joint react by either shaving the lower teeth off (as in my cam lobe), breaking the veneers (common) or jambing the joint. These patients are often required to wear a "night guard" to protect the restorations. I'll admit that being old school makes me something of a dinosaur but <span style="font-style: italic">form follows function</span> still rules. That said, perhaps I should have been satisfied with a stock engine.

 

[RonMacPherson]

Did a little research a couple decades ago. Biggest problem was some kind of guide to keep the lifters from turning in the bore.. None of the cam people that I talked to had any lifters that they thought would work. Bore diameter, etc. was no problem. Their concern(Isky, Crane, and a couple of others, forget who right now) was the clearance above the bore, to provide for an interconnecting link, or possibly machining a groove down the bore for a pin on the body of the lifter to keep it from turning.

I never got to get inside and take precise measurements of the clearance and get back to them before I got carried away. Mebbe Brosky can have his machinists do that and get with Elgin cams in the Bay area to see what he can come up with as far as roller tappets??????

 

[Brosky]

Ron,

That might have been possible if Dema Elgin ever answered one out of four phone messages properly or replied to very detailed emails on his suggested input forms.

Sometimes I really get tired of begging people to take my money. As easy as he is to deal with, I wish my machinist could supply all of these parts, but he doesn't have the time to search, so I'm doing it. It's fun, but frustrating when things like that happen.

I'd rather have him running lathes and boring machines than looking for parts anyhow.

 

[2wrench]

Ouch, Bill! Okay, at least I think I have remained
conservative, at least somewhat. Shaved head to
increase compression.

I think the cam I chose is somewhat moderate.
Hope I don't screw up installation of machined
parts, etc.