HI everyone - I have been away for 7 weeks and this post to our chat room
below was forwarded to me by Bruce as a follow up to his previous
information a couple of months back-I have a photo of his high top piston
designed by a specialist race engineer but cant post to this site.
Regards Peter Yeomans
"Hi Guys,
Pardon my intrusion into this forum but I may be able to throw some more
light on FW engines.
A few observations after playing with many FW engines over the years.
FWP 1020 early blocks have no lumps on the side for crank clearance in 1500
size so are only really useful for 1100 engines. They can be used and the
trick was to take the oil in and out of the crankcase side to the cooler /
filter.
The head has no generator mount on the front but it can be used in extreme
cases. The chambers are quite a bit deeper than FWA/E car heads and need to
have high crown pistons to be really of any use.
I have also measured differences of up to 0.060" in depth measured at the
valve centre lines to the chamber face between the valve heads. The
shallowest head was 0.516" the deepest was 0.577"
A standard FWA /E car engine head is close to 0.420" in depth.
The chamber widths are also markedly different.
FWP and E heads are usually a touch under 3.0" wide whilst FWBP heads vary
from 3.164" up the 3.207"
The FWB head is low compression with deeper chamber and shorter valve by
about 3/16". The pistons used where also dished to lower the compression
ratio.
However the valve sizes on the FWBP 1500 head are bigger than the FWE. So if
you have an FWBP 1500 pump engine, with the use of high top pistons with a
wedge built on top you can get good compression ratio without milling the
head face. This is desirable as it leaves the head nice and strong. We are
doing a race engine right now with this set up.
I'll keep you posted on results in next couple of months.
By the way the FWBP block came in two sizes, 1020 and 1500 the only
difference being in the bore for the liners and the crank stroke.
The nice thing about these FWB blocks is that they are identical to the FWE
block but do need to have the extra oil gallery and take off drillings done
to make them work as replacements for ruined FWE blocks.
I have two of them running in Elite race cars with absolutely no problems.
We make a crank case stiffening systems and use fully counterweighted billet
cranks with "phantom" 2 & 4 mains. With a light flywheel and special JE
pistons and good rods these engine will spin reliably to over 8,000 RPM We
also line bore the blocks to suit the Ford/MG bearing set up but tighten the
tolerances, as the blocks expand more than you think when hot. We experience
oil pressure of 70 psi hot running on a standard car type oil pump. I also
reduce the amount of oil that goes up to the cam shaft a bit by using an
adjustable flow valve in the valve gear take off port in the side of the
block.
I hope this info helps.
Cheers,
Bruce Mansell
