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RE: 1975 1500 Engine Rebuild

To: Michael Graziano <mgraziano@mindspring.com>, Jeff Wilson <jwilson@accmail.umd.edu>, spridgets@autox.team.net
Subject: RE: 1975 1500 Engine Rebuild
Date: Tue, 1 Aug 2000 05:46:22 -0700 (PDT)
Jeff,

Mike is pretty much on target...must be a full moon.
:o)))

British Leyland realized they had a problem with the
radiator size and had corrected it with all vehicles
manufactured from October '75 forward. If you truly
have the smaller radiator, REPLACE IT!

The 1500 Midget is under cammed for the most part.
going with a little wilder cam should benefit unless
you have strict emission laws in your area...there are
ways to get it to pass though.

Mike Graziano and I bounced many of these improvements
off each other as well as those that we entrusted to
rebuild our engines. I sent my engine to Ted
Schumacher for the rebuild. Ted has been in this
industry for 30 yrs or more and is a straight shooter.
He'll give you his opinion regardless. He's not the
type to sell you something you don't need. 

As far as balancing the engine back to the pressure
plate...You don't need to balance the pressure plate.
If you are racing the car then yes...balance the
pressure plate, otherwise, there is no need because
when you change your clutch down the road, you'll be
replacing the pressure plate anyway...so...need I say
more?

I don't have an extra dual setup but I do know where
you can probably get one. Quantum Mechanics in
Conneticut is a good source for the carb setup...also
a great place to get your tranny rebuilt if in need.
Let me know if you want the number.

As a closing, I would like to state for the record
that I'm gaining nothing for advertising the two
previously mentioned businesses. I'm just a very happy
customer of both individuals and have received top
quality advice as well as service from both of them.

Dan Dwelley
77 Midget
Alexandria, Va.
--- Michael Graziano <mgraziano@mindspring.com> wrote:
> Jeff,
> 
> There's a lot of thought out there on what things
> need to be done on the
> 1500 block.
> 
> But there are several things that really should be
> done to increase the life
> of the engine.
> 
> First,  have the main oil galleries drilled out to
> allow for more oil flow.
> Add to that an oversized oil pump.  APT has one. 
> Getting oil throughout
> this engine is extremely important.  And keeping it
> cool is just as
> important.  So add an oil cooler kit.
> 
> The thrust washers on the 1500 blocks have a nasty
> habit of falling into the
> oil pan when they wear out.  To prevent this,  have
> the machine shop pin
> them in.  Once they fall out and the crank rides on
> the block,  you might as
> well get a new block 'cause that old one just became
> a big, heavy paper
> weight.
> 
> One idea is to also use the cam to a Spitfire 1300
> and have the 1500 block
> machined to accept cam bearings.  Yes,  the 1500
> does not use bearings on
> the cam.  Yet another reason why good oil flow is
> imperative.  I didn't
> machine for cam bearings.
> 
> As for the head.  I used a 285 cam with the vernier
> gear set to a TR6 (twin
> chain) and advanced the cam 4 degrees to bring the
> power range down.  I
> didn't open up the intake or exhaust valves,  but I
> made some nice DEEP D
> shaped pockets behind the valves (for good puffing
> action) and did a
> _little_ opening of the intake and exhaust ports,
> mainly to smooth them
> down.  Too smooth apparently isn't good either. 
> Twin springs to complete
> the head.  Also,  the machine shop shaved a hair off
> the head and the block
> to ensure a good seal.  MGTs (where I had my engine
> done) uses a real good
> head gasket set, rather than the one from Moss.  And
> the ARP head studs are
> 3/8" too short.  I had to use Moss studs (9) and one
> original stud.  Yes,
> one of the Moss studs stripped (no, not the nut) at
> 40lbs on the torque
> wrench.  Yes,  the torque wrench was calibrated
> correctly.
> 
> For carbs,  Dan Dwelley and I opted for the UK spec
> SU HS4's, which have the
> 1 1/2 inch venturi.  Opinions vary on which are
> better, the Weber or the
> SU's.  The DGV isn't a performance carb.  I think
> Dan has an extra set
> complete with linkage and intake manifold.  Dan?  I
> used a set of stock MGB
> Ram pipes in conjunction with K&N 6" round filters.
> 
> Cooling is an issue as well.  The '75 uses a smaller
> radiator than the later
> cars.  You may want to upgrade to a later radiator,
> or think about the GEO
> aluminum radiator conversion.  I don't know much
> about it.  I used my stock
> radiator (which is about 3" longer than yours), but
> recored with a 3 row
> louvered fin core.  Three row staggered cores are
> better,  but they are
> really to wide for our engine compartment.  Some
> list members use a 10 or 12
> inch electric fan for better cooling,  but since the
> motor was peppier,  I
> went with the mechanical water pump and fan from a
> '74 Spitfire.  No clutch,
> and a much higher CFM.  We did have to cut and
> reweld both the shroud and
> mounting brackets in the car to bring the radiator
> forward 3/4 of an inch to
> prevent fan contact at high RPM, which moves those
> fan blades quite a bit
> forward.  If you get the larger radiator,  you also
> need to find a later
> mounting bracket for the overflow tank as the stock
> bracket mounts too far
> forward.
> 
> For exhaust,  I used Moss' 4-2-1 header and a Monza.
>  It's really loud,  and
> I'm contemplating adding something in-line to quiet
> it down.
> 
> If you're changing the pistons,  go with the high
> compression ones (non
> dished) which are 9:1 vs. 7.5:1.  Available in
> standard, 10, 20, 30, and 40
> over.  I used the hepolite 030 over pistons.
> 
> And make sure the rotating mass is balanced.  From
> front pulley, to crank,
> rods, pistons, flywheel, and clutch pressure plate.
> 
> As my car was completed yesterday,  and I only have
> 96 miles on it, I can
> only say that it's extremely peppy, that cold oil
> pressure with 20w50 is
> 80lbs and 50 hot, and that the engine temp remains
> at 165/170 in 80 degree
> weather.   I haven't stepped hard on it yet b/c of
> break-in,  but it REALLY
> looks to go.  We shimmed the oil pressure relief
> valve to get that oil
> pressure up.  I'm changing to synthethic at 2 to 3K
> miles, after everything
> has had a chance to settle in.
> 
> Good luck with the rebuild.  Ted Schumacher at TS
> Imports in Ohio is worth
> giving a phone call as he is excellent with the
> triumph motors.  He helped
> Dan and I out quite a bit when we had questions. 
> He's where I got the
> Vernier gear set.  Not an easy thing to locate.  Rob
> Medynski at MGTs has
> them fresh on the brain as I bombarded him with
> opinions on what we needed
> to do to get the best compromise of power and
> durability from a 1500.  He's
> very helpful on the phone as well.  And I know he
> has a few overflow bracket
> on parts cars, as well as a radiator.  I have a
> spare radiator that needs to
> be recored that you can have for shipping if you
> want.  Otherwise,  to the
> trash it goes.
> 
> Hope this helps.
> 
> Michael
> '78 Midget (amongst the living once again)
> '87 300ZX
> 
> -----Original Message-----
> From: owner-spridgets@autox.team.net
> [mailto:owner-spridgets@autox.team.net]On Behalf Of
> Jeff Wilson
> Sent: Sunday, July 30, 2000 1:56 PM
> To: spridgets@autox.team.net
> Subject: 1975 1500 Engine Rebuild
> 
> 
> Head Work,
> Thoughts on Head milling (amount) and increasing the
> Size of exhaust
> valves (size - type),
> I have already secured a higher performance cam and
> Webber down draft
> and would like to hear of any other engine
> performance feedback.
> 
> Jeff
> 
> 


=====
Dan Dwelley
77 Midget
Alexandria, Va.

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