The "rocking" method for cam timing is by far the most accurate as long as
the cam grind is symmetrical about top dead centre.
John Kipping
----- Original Message -----
From: "Charly Mitchel" <charly@mitchelplumbing.com>
To: <ejmajor@attbi.com>
Cc: "FOT" <FOT@autox.team.net>
Sent: Tuesday, May 20, 2003 5:12 AM
Subject: Re: Fuel starvation problem
> Ed,
> I timed the cam with a vernier gear and set the cam to the exact time the
> valve should be opening i.e.: I took the opening of the intake valve, 34
> degrees btdc and set the cam with a lifter in place and also added the
valve
> lash .018", to the timing. I am in some kind of agreement with you and I
> 'm considerating that as a possibility also.
> Does this sound like the way to time the cam?
> Charly
> ----- Original Message -----
> From: <ejmajor@attbi.com>
> To: "Charly Mitchel" <charly@mitchelplumbing.com>
> Cc: "FOT" <FOT@autox.team.net>
> Sent: Monday, May 19, 2003 9:25 AM
> Subject: Re: Fuel starvation problem
>
>
> > Your problem is one I fought last year only to find that my mechanical
> timing
> > was off by about 24 degrees. (I won't comment how I did that in the
first
> place)
> > Your setup is similar to my TR250 (webers/60 over/header/etc.), We
proved
> it by
> > using the Bentley Book method of checking the cam timing to the crank by
> > setting the 11 & 12 valves to 120 thousands and getting them to the
point
> of
> > rock (one opening one closing at the same gauge measure) at that point
you
> > should be at TDC. After resetting the cam timing it ran fantastic,
> climbing
> > right thru 6000 RPM
> >
> > --
> > Ed Major
> >
> > '58 TR3A, '68 TR250
> > ejmajor@attbi.com
> > > I'm having a problem tuning my TR6, the motor is bored .030", the head
> is
> > > about 3.375 thick (compression ratio 10.25:1) and has been modified to
a
> > > stage 2 configuration, the pistons have been shaved to all be the same
> > > height and the block decked to 0 clearance, the engine has been
balanced
> the
> > > rods and flywheel have been lightened, I use stock pushrods with stock
> > > rocker arms and spacers in place of springs, the cam is a D9 grind,
the
> > > distributor is a 22D that has 17 degrees stamped on the rotor and has
a
> > > Pertronix unit instead of points, it has a header that has long center
> > > branches that go to a 2 1/2"collector & pipe and routed similarly to a
> stock
> > > system with a 2 1/2" Flowmaster muffler, I'm running triple DCOE 40
> carbs on
> > > it.
> > > I can't seem to get the car to rev over 5000 rpms at load! I'm
running
> AV
> > > 101 fuel in it, I have a double ended fuel pump on it (not SU) and a
> > > pressure regulator. I seem to be able to get consistent fuel pressure
> > > between 3 1/2 and 4 1/2 psi.
> > > I've tried rejetting the main jets, originally they were 120, and
I've
> > > gone to 130 & 140, I've played around with the air correctors going
from
> 160
> > > to 150 & 140. The venturi's are 30's. I've played with the timing
and
> > > advanced as far as I dare and it seemed to run the best when I had the
> > > advance set at about 17 degrees at idle, about 32 or 33 degrees at
4000
> rpm
> > > (hard to tell the exact advance with my timing light).
> > > The car runs good up to about 4800 rpm and then it starts to pop
through
> the
> > > exhaust, sounds like a misfire, and barely revs to about 5200 rpm's.
> This
> > > rpm reading is done with the stock tach and could be reading wrong
also,
> I
> > > plan to find a high rpm test tach to verify my stock tach accuracy.
> > > Any ideas? I keep getting stuck on the carbs, think they are running
to
> > > lean, but when I put in the 140 main jets, fuel was actually coming
out
> the
> > > stacks when I went WOT!
> > > Charly Mitchel
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