We have taken some care with the Accusump on our SCCA FP 1500 Spitfire. It
helps a lot. At Texas Motor speedway during heavy braking at the end of the
first banked turn the oil pressure would drop from above 60 to about 40 (the
low pressure in the Accusump). It would stay there through the tight left
hander following this breaking and not return to above 60 until the end of
the short straight. I am convinced this was due to to Accusump and without
it we would have blown the engine like we had once before when we thought
the Accusump was not working. The pan is original size but is internally
baffled front and rear with a windage tray in addition to a horizontal
baffle. The Accusump has an electronic valve and a mechanical one way valve
to assure it charges the gallery and not the sump, per previous discussions.
Matt
> From: "T.R. Scratchings" <wob@dandrade.freeserve.co.uk>
> Reply-To: "T.R. Scratchings" <wob@dandrade.freeserve.co.uk>
> Date: Thu, 26 Jun 2003 16:33:28 +0100
> To: <fot@autox.team.net>
> Subject: Fw: Oil Starvation-- Solution needed
>
> ----- Original Message -----
> From: "Chuck Arnold" <chuck.arnold@oracle.com>
> To: "T.R. Scratchings" <wob@dandrade.freeserve.co.uk>
> Sent: Thursday, June 26, 2003 2:23 PM
> Subject: Re: Oil Starvation-- Solution needed
>
>
>> Thank you very much for the comprehensive response.
>>
>> Chuck
>>
>> "T.R. Scratchings" wrote:
>>
>>> Check out all the other bearings. If #1 main has failed, that's the
> cause of
>>> starvation to #1 rod bearing, period.
>>> If other bearings show signs of failure, then you have a supply problem.
>>> Glacier (aluminum) bearings have better embeddability (ability to cope
> with
>>> debris) than lead/copper (Vandervell etc.), which are harder. We always
> use
>>> the latter type, which are still available up to +020" U/S. Get a set of
> ARP
>>> rod bolts, then have all the rods resized at the correct torque
> loading,
>>> including the new one. Check also for twist & bend on the rods. The MGB
> rod
>>> bearings require resizing of the crank, plus ensuring that the extra
> width
>>> doesn't run into the radii, plus enlargement of the tang slot in each
> half
>>> of the rod. Carrillo rods used to incorporate this as standard, but
> don't
>>> now do so unless requested.
>>> Get off Mobil 1- it's way too thin at cold, and use an oil with good
> cold
>>> viscosity, minimum 15W. Leaks will then disappear also. Valvoline Racing
>>> 20W/50 is good, or use a good semi-synthetic. We've never got on very
> well
>>> with full synthetics in these old engines. It's a different story in the
>>> trans & rear end, however, where full synthetics work great. Top end
>>> lubrication issues will not cause a failure of one rod bearing
> alone,unless
>>> the feed is from the extreme rear of the gallery, when # 6 may fail. Oil
>>> pumps sometimes give poor idle pressure; that's due to poor manufacture,
>>> giving excess clearance between end plate and rotor/sleeve assy. Lap in
> the
>>> body to get the end float right down to 0.002" max. Don't run a deep
> sump
>>> unless you extend the pump pickup to suit.
>>> Good luck Jon Wood
>>> ----- Original Message -----
>>> From: "Chuck Arnold" <chuck.arnold@oracle.com>
>>> To: "6pack digest" <6pack-digest@autox.team.net>; "FOT"
> <fot@autox.team.net>
>>> Sent: Wednesday, June 25, 2003 2:25 PM
>>> Subject: Oil Starvation-- Solution needed
>>>
>>>> The shop finally got my frozen engine apart. The verdict was oil
>>>> starvation in number 1 cylinder. Rod bearing gone, rod shot. Piston
>>>> OK. Now I am looking for solutions before putting it back together.
>>>> Car is TR6 with 170 HP at the wheels used for the track. Has an oil
>>>> cooler and uses about 6 quarts to fill. Used Mobil1.
>>>>
>>>> Kas has the illustrations for a deeper oil pan and a baffle -- but I
>>>> need more information about its installation, and the collected wisdom
>>>> of the group to help me get it right before I do it again. Will/would
>>>> an Accusump help this problem?
>>>>
>>>> Thanks,
>>>>
>>>> Chuck
>>>>
>>>> [demime 0.99d.1 removed an attachment of type text/x-vcard which had a
>>> name of chuck.arnold.vcf]
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