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Camshafts
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DNK
Great Pumpkin
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The lifters get noisy is one,
Shawn 's a lucky one.
I did this last winter. The manifold,front cover,radiator all will come out then you can do the cam and parts. While I was there I also changed the heads to 4.0 since it was very little work from that point. Oh yea, headers could be done too.
See it opens a whole big can of worms
Shawn 's a lucky one.
I did this last winter. The manifold,front cover,radiator all will come out then you can do the cam and parts. While I was there I also changed the heads to 4.0 since it was very little work from that point. Oh yea, headers could be done too.
See it opens a whole big can of worms
OK, I guess I need to be listening for noisy lifters, (great i'm hard of hearing, to many things going BOOM in my prior life), but it looks like there might be some way to measure them, that would be in the service manual, right?
Also, th PO has installed a switch under the dash for the fuel pump or maybe the oil pump, is it possible the oil pump could be started up before the engine starts up?
I know, stupid questions,
thanks for the help, Tom
Also, th PO has installed a switch under the dash for the fuel pump or maybe the oil pump, is it possible the oil pump could be started up before the engine starts up?
I know, stupid questions,
thanks for the help, Tom
The problem isn't the camshaft itself. Other factors lead to camshaft failure. The TR8 has a flat tappet camshaft. That means that the camshaft lobes ride directly against the lifters. This was common many years ago on V8 pushrod motors. Nowadays roller lifters are used to cut down on the friction. Moderns oils do not prevent premature cam wear on flat tappet motors. Most oils now lack the key ingredient needed for flat tappets called ZDDP. Google it, there are tons of articles about this and what oils still have it. Now if you are talking about the rash of replacement camshafts going bad, there are other factors at work here. Proper break in is essential using regular oil- not synthetics. New lifters must be fitted with a new camshaft. There was a batch of bad camshafts about 3 years ago. At least that was what was talked about behind the scenes. Publicly bad break in procedures were commonly blamed to avoid warranty issues. Another leading cause of failure can be excessive valve spring pressure on the heads that have been rebuilt with bigger valves and use different springs. Lastly, oiling can be a culprit. The oiling system on a Rover V8 and Buicks that use the same front cover and oiling system, are not the greatest to start with. Steel gears riding in an aluminum pump housing cause wear rings in the aluminum. This slowly over time leads to diminishing oil pressure and volume.
The 4.0 heads aren't going to give you much more HP at all. They will bump your compression from 8.13 to 9.35 assuming they were not milled. Intake runners are slightly larger. I'd be stunned if you get 5 more HP simply by switching from stock 3.5 heads to stock 4.0 heads. Now if you take the time to port the heads and fit larger valves, there is more HP to gain. The head flow numbers are fine for anything up to about 4.0 liters. Over that the heads just can't deliver enough air to adequately supply high revving big displacement motors.
The 4.0 heads aren't going to give you much more HP at all. They will bump your compression from 8.13 to 9.35 assuming they were not milled. Intake runners are slightly larger. I'd be stunned if you get 5 more HP simply by switching from stock 3.5 heads to stock 4.0 heads. Now if you take the time to port the heads and fit larger valves, there is more HP to gain. The head flow numbers are fine for anything up to about 4.0 liters. Over that the heads just can't deliver enough air to adequately supply high revving big displacement motors.
