Thanks for all the great feedback, I am taking head off tonight and my shop is
going to change the clearances to .0025 intake and .0035 exhaust. He really
really disagrees with changing it.
The shop asked if I could get recommendations for intake and exhaust valve
spring pressure. I have a Ted Schumacher b Fb grind race cam. Tubular rods and
stock rocker arms.
Thanks
Mike
Michael T. Moore, CPA
2007 West 32nd Street
Erie, PA 16508
Phone: 814-868-4831 ext 103
Fax: 814-864-7383
-----Original Message-----
From: gregmogdoc@surfnetusa.com [mailto:gregmogdoc@surfnetusa.com]
Sent: Monday, June 30, 2014 2:27 AM
To: Michael Moore; fot@autox.team.net
Subject: RE: [Fot] Valve Clearance, sorry for long winded question
When a valve sticks, it sticks at least partially open. The cylinder instantly
loses all power.
Because the valve is open, the valve clearance is grossly excessive. If there
is a muffler on the car, you should hear a sudden loud tapping. I would also
expect to see visible signs of "pounding" between the end of the valve stem and
the rocker. Often the adjuster ball will jump out of the cup on the end of the
pushrod & land on the edge of the cup. This may leave a witness mark or may
crack or fracture the cup causing it to fail later.
Greg Solow
The Engine Room
Sports Car Specialists
Santa Cruz, CA 95060
831 429-1800
------- Original Message -------
>From : Michael Moore[mailto:mmoore@mtmcpafirm.com]
Sent : 6/29/2014 12:18:54 PM
To : fot@autox.team.net
Cc :
Subject : RE: [Fot] Valve Clearance, sorry for long winded question
What would be the effect of sticking valves, not catastrophic in nature.
At end of straight, every run, last week at Mosport,
#4 cylinder went cold and
I had to pull over and wait a minute for it to come back, sometimes turning it
off.
At track I changed fuel lines to split to each carb, change facet fuel pumps,
removed regulator, rebuilt rear card, put in new distributor, cap, peteronix,
coil and swapped wire with some old used ones.
Nothing worked.
After weekend found the top of #8 push rod came off when I removed rockers and
rod was slightly bent. Engine builder thinks top coming loose was cause as it
may have been jamming up and holding valve open
Installed new carter pump, new regulator, and Y splitter at home.
Put it in dyno the other night, after replacing rods, happened 1st pull again,
then we switched plug wires, and could not get it to occur again.
However, at high rpm, say over 4500, when accelerating hard, it would start to
break up.
We seemed to solve some of the problem with needle swaps and adjustments. But I
wonder if at high rpms valves are binding.
Builder has great reputation, I trust him, he has been helping for no charge.
he removed some valve springs and sees no signs of a sticking valve.
Thanks
Mike
62 TR4, Race car
63 TR4, Street car
Mike & Becky Moore
6050 Ruhl Road
Fairview, PA 16415
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