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TR4/4A My 4a's introduction & project[s] thread

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I'm going to use the TR3 draft tube too. I like the look of that K&N valve cover breather. Might get one of those as well.:smile-new:
 
I like the looks of the breather as well, but don't fully understand its function. I did a little reading on it tonight and from the sounds of things it reduces power at high speeds - am I/the other posters wrong?
 
BillyB62 said:
I like the looks of the breather as well, but don't fully understand its function. I did a little reading on it tonight and from the sounds of things it reduces power at high speeds - am I/the other posters wrong?
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Hmm, where did you read that? I don't see how it is possible, but I'm curious about the theory.

In this case, the road draft tube sticks down into the airstream under the car with an angle cut to the rear. At least in theory, at higher speeds, the airflow pulls a slight suction on the road draft tube. The breather on top allows fresh, clean air to enter the crankcase and flush away the blowby fumes which (again in theory) would otherwise contaminate the oil, contribute to varnish formation and so on. Under extreme conditions (low speed, full throttle, tired engine) it may also flow backwards but hopefully that won't happen.

The original "road draft" setup (on earlier TRs) was similar, except the air intake filter was built into the oil filler cap. On my TR3, I get to wipe away the oil that drips from it, no doubt carried there by air coming out instead of in :)
 
Much time has passed since my last update and I'm sure like lots of you the weather and timing has finally permitted us to start driving again!

Update! Really happy with the way the car has turned out & it run greats! I think the stuck float on one of the carbs which I had resolved last year (right before my water pump began to leak) made a significant difference in the cold-start drivability. It now starts and idles - something I thought these cars never really quite did that well. Suspension & brakes are into the modern age (besides the ride quality when you hit some rough road). Gone is all the play in any sharp turns, car remains very flat through turns... It's quite fun!!!!

I've posted some new photos on another thread!
 
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