Yeah I was gonna tell Walt that tomorrow, If one pump can't supply
sufficient fuel to the carbs how can it supply
sufficient fuel to the next pump in series.
I get my by pass valves from Kinsler injection, their sprint car guys.
On Mon, 17 May 2004 20:39:03 -0700 Bill Babcock <BillB@bnj.com> writes:
> BTW, there are a lot of alternatives to insufficient fuel delivery.
> You
> should check your float levels very carefully. The best way is to
> pull the
> emulsion tubes and look down them with a flashlight. One of the
> tubes has a
> feed hole on one side. Blow gently down the tube and see if the gas
> level
> rises back up to where it just reaches the hole. That's perfect
> float level.
>
>
> A quick check for weak spark (which can easily cause the problem you
> are
> describing) is to narrow the plug gap to about .015". You don't want
> to run
> there permanently because it's easy to foul that small of a gap and
> you want
> a fatter spark, but voltage-caused problems will generally go away.
> Likewise, if you open the gap to .050" it will get a lot worse.
>
> Incidentally, a second pump in line will not increase the flow much,
> it will
> increase the pressure. You want the pumps in parallel to increase
> flow--just
> like batteries. Its funny, when people are explaining voltage,
> current and
> resistance they use pumps and water as the analogy, and here I'm
> using
> electricity to explain pumps.
>
> -----Original Message-----
> From: owner-fot@autox.team.net
> To: fot@autox.team.net
> Sent: 5/17/2004 5:40 PM
> Subject: out of fuel- I think?
>
> I could use a little help from some FOT members that drive TR6s
> with
> triple
> Webers.
> In hard street use and SCCA autocross events I have no problems.
> However,
> this past weekend I was club roadracing
> on our Albuquerque, New Mexico 14 corner 1.65 mile road course.
> After
> the
> 4th or 5th lap on full throttle the engine started falling flat as
> if I
> dropped a couple of cyclinders due to lack of fuel (110 octane
> racing
> gas).
> I had to fall back in the pack and not push too hard (not difficult
> with
> my
> driving skills) or things would just run flat. I suspect I do not
> have
> the
> volume of fuel I need for this racing application.
> My engine is putting 155 hp to the ground (just did a chassis dyno
> last
> week) with a few more ponies to be found with some more tuning. We
> are
> racing at 5,500 ft. above sea level. I have 10.5:1 compression,
> ported
> heads, stiffer valve springs, 286 cam, headers and triple Weber 40
> DCOE
> carbs. My main jets are 200 air and 115 fuel. Emulsion tubes are
> F7.
> Idle
> jets are 55, acelerator jets are 40 and the bleed off is set at
> zero. I
> am
> using the cheap electric fuel pump you can get at Pep Boys which
> has
> performed OK up till now..If it is the higher volume of the two
> types
> they
> sell. A fuel pressure gauge shows I am getting between 2.5 and 3 PSI
> of
> fuel
> to the carbs. I am not using the stock mechanical TR6 fuel pump at
> all.If my
> problem is in fact not enough volume things now get difficult. Do
> you
> think
> I can just hook up a second (same type) fuel pump in line to
> increase
> the
> volume a little or am I going to have to find a high volume, low
> pressure
> fuel pump with a return line back to the gas tank.
> Has anyone else came across a similar problem?
> Any suggestions?
>
> Thank You
> Walt Hollowell
> Albuquerque, New Mexico
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