Make sure you make the shims out of used Watney Red Barrel beer cans !!!!!
"Bowen, Patrick" wrote:
> Another option to planing the head and having to argue with the difference
> in height with the pushrods, is to plane the block. The benefit of this is
> you take less off to raise the compression more. Since you are removing
> less the actual height difference will be less for the pushrods. This has
> been recommended to me many times by spit Racers. Another option to combat
> the taller pushrods, is to make shims out of aluminum cans or such and put
> them underneath the rocker shaft pedestals -- important make sure you create
> oil holes in the shims where required!!!
>
> Patrick
> as for the octane/compression issue that is all up to you and what you want
> to do.
>
> -----Original Message-----
> From: Vic Whitmore [mailto:vicwhit@home.com]
> Sent: Friday, December 01, 2000 9:08 AM
> To: Graziano, Michael; sos@kymtnnet.org; Spitfires Maillist
> Subject: Re: Engine Rebuild
>
> Michael, that was a great reply, lots of info. I was particularly interested
> because I'm starting the process of adding a little oomph to my Spitfire
> 1500.
>
> You mentioned the "Make nice big D shaped pockets under the valves". I have
> seen
> this mentioned more than once but I don't fully understand it. I am
> practicing
> on a 1500 head now before working on my good one so I would like to know
> what is
> meant by D-shaped. Is the flat of the D across the plane of the valve
> opening?
> The fuel path is coming in on the bottom flat of the D. True?
>
> Here is the list of current items in my project:
> Port and polish head
> Weber DGV with Pierce manifold
> 4-2-1 header and big bore SS exhaust from Rimmer's (Phoenix Performance
> Exhaust)
> Air/Fuel Ratio Monitor from CB Performance (for final carb tuning)
>
> Yet to decide:
> Flat top pistons. I haven't had the head off engine yet and don't know if I
> might have flat tops already. Most likely not as it is a 76 California
> version.
> Replacing pistons means further dismantling of the engine and machine shop
> work
> to bore out for oversize. I would like to avoid the extra cost of machine
> shop
> work and the extra cost of a piston set.
> High Performance Cam. Requires further dismantling of engine (beyond just
> the
> head). I am looking for a wider power band rather than peak at high RPM so a
> "Road Cam" seems to be the right choice. Which cam do I use? Buy a new one
> or
> send mine off for re-grind?
> Plane the head. Requires machine shop work. If so, how much. The competition
> manual says .200" but then you get into further problems dealing with the
> push
> rods. I prefer to avoid this and go with just the flat top pistons. This
> will
> raise the compression to around 9:1 I think. Planing would raise the
> compression
> even more and create other problems such as pinging and the need to use
> higher
> octane fuel.
>
> Vic Whitmore
> 76 Spitfire
> Thornhill, Ontario
>
> "Graziano, Michael" wrote:
> >
> > Larry,
> >
> > I too haven't seen much in response.
> >
> > Here's what I did to my 1500 Midget, which seems to be working well for
> me.
> >
> > +0.030 Flat Top Hepolite Pistons
> > 285 Piper Cam Advanced 4 degrees via TR6 Double Chain Vernier Gear Set
> > Pinned Thrust Washer (some people fit MGB thrust washers)
> > Balanced Rotating Mass (crank, pistons, rods, pressure plate, flywheel,
> and
> > pulley)
> > Oil Cooler
> > GM 63 amp alternator
> > Lucas 25D4 points dizzy (eventual upgrade to Mallory dual point)
> > Ported, skimmed, and intake matched head.
> > (no chamber work, and not polished too smoothly. I can't remember
> > if I
> > read it in Vizard, or the BL competition manual, but someone did
> > not
> > recommend polishing this head, other than removing all the burrs
> > and
> > casting imperfections. Make nice big D shaped pockets under the
> > valves
> > for better puffing action. Standard valves)
> > Dual Valve Springs to eliminate possible lifter bounce.
> > 4-2-1 Exhaust header, mild steel (the 4-1 is best at high RPM, the 4-2-1
> has
> > a bigger range)
> > Monza free flow. Dual exhaust may be hurting your exhaust suction...
> > forget the term...
> > Dual HS4s with CapStat jets
> > '74 water pump with no clutch and a '74 fan
> > Backup 10" electric pushing fan
> > 3 row louvered radiator 1/2" thicker than stock for a Midget. You may be
> > able to fit
> > a 3 row staggered in the Spit, which is better. Transfer tubes
> are
> > 3/8", I believe.
> > Skimmed block (not too much)
> > Standard studs (I didn't use the ARP studs I purchased. Still have them,
> > though)
> > Bored out main oil galleries and high capacity oil pump. Shimmed oil
> > pressure relief valve.
> > Currently running 90 lbs cold and 25-30 lbs hot oil pressure.
> > Some people retrofit cam bearing from a 1296 cam. Might be a good idea,
> if
> > cash is no object.
> >
> > For tuning purposes, I purchased a Air/Fuel Ratio gauge, but haven't
> > installed it yet. A definite must if you plan on screwing around with
> your
> > needles. Out there somewhere in the archives is the link to the SU needle
> > program which references different needle profiles to needle codes.
> >
> > You can always add a supercharger, and nitrous.... Seems a bit much for
> me.
> > When all is said and done, the Corrolla next to you will probably beat
> you
> > in the next street light race anyway. I thoroughly enjoy the added power
> in
> > my Midget, but recognize it's limitations. I also try not to race it at
> > the street lights. I spend too much on the rebuild to risk damaging it.
> >
> > Michael
> >
> > -----Original Message-----
> > From: Vic Whitmore [mailto:vicwhit@home.com]
> > Sent: Thursday, November 30, 2000 8:56 AM
> > To: Larry Elswick; Spitfires Maillist
> > Subject: Re: Engine Rebuild
> >
> > Larry, I haven't seen much in terms of replies to you. Hopefully, there
> has
> > been
> > some off-list.
> >
> > I expect that you have a copy, or have seen the competition preperation
> > manual.
> > You can find a copy of it at:
> > http://homepage.ntlworld.com/mark-kaye/thumbs/Spit-comp-man.pdf
> >
> > You seem to be following a good path with the HS-4 (once the jetting it
> set
> > right), header, etc. I would suggest the next step is to port and polish
> the
> > head.
> >
> > I think the reference to the 1300 is just for the head. There were bigger
> > intake
> > valves involved but you can have them retro fitted to your 1500 head at
> the
> > same
> > time you get the valves/seats triple cut. A good machine shop should be
> able
> > to
> > do it. I am unclear on whether the bigger intake valves were for the 1300
> or
> > the
> > early 1500 so you may need to check on that.
> >
> > There are several other listers that have done a lot of race prep on their
> > cars.
> > Maybe they can help with more suggestions.
> >
> > Vic Whitmore
> > 76 Spitfire
> > Thornhill, Ontario
> >
> > Larry Elswick wrote:
> > >
> > > I'd like some suggestions on a performance rebuild of
> > > my 1976 1500. One suggestion was to use a 1300 engine.
> > > I'm talking about every trick in the book to squeeze as
> > > much performance out of the engine as possible. It currently
> > > has twin HS-4's, exhaust header with dual exhausts, and
> > > electronic ignition. I do plan to blueprint and balance it.
> > > Any help would be greatly appreciated. Thanks!
> > > Larry
> >
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