Les Myer wrote:
>
> >Clip........Anyhoo, the 1500 makes the 1275 a total road rocket in
> >comparison. In an attempt to make the 1500 more responsive, last week I
> >removed the air pump belt and reset the timing from 2ATDC to 12 BTDC. This
> did >not make any difference to the acceleration. What's puzzling is that
> the >sluggard has an approx 20% increase in engine displacement over Binky.
> The mpg >is also abysmal - 20 compared to about 28 for Binky. The plugs
> seem to look
> >OK - no carbon at all. The drive seems a little more smoother than Binky
> >but that is a combination of many things, I suppose. I'm wondering if I'm
> >missing anything. Of course, Binky has twin SU's and Doe-Doe has a single
> >Z-S - is that the problem?
> >
> >Regards, Adrian
>
> Hi Adrian,
>
> I'm no expert on 1500s, but I imagine the Brits did things similar to what
> was done on American cars to meet emissions standards. The technology of
> the 70's reduced emissions by lowering compression ratio, adding a catalytic
> converter/smog pump/EGR Valve, retarding camshaft timing, retarding ignition
> timing/altering advance curves, and leaning the fuel mixture - most of which
> resulted in a degradation of performance and mileage, but with cleaner
> emissions at a minimal cost to the manufacturer. Eventually this type of
> strategy proved to be inadequate and forced the introduction of computers,
> then mass production fuel injection, and finally total re-design of the
> powerplant at considerable cost to both the manufacturers and consumers.
> Cars are expensive these days, but you have to admit the performance is is
> better than ever.
>
> Back in the mid-70s, I know Ford retarded camshaft timing by building the
> retard into the camshaft gear. All we had to do is use an older timing gear
> set, an older distributor/intake/carb, and headers - the engines would wake
> right up to these mods. If you wanted a screamer, you put old heads on,
> replaced the dished pistons with flat tops, and went with a performance cam.
>
> I imagine the 1500 would respond dramatically to the right combination of
> modifications that deal with all of these areas, but someone else will have
> to tell you what they should be. The 1275 happend to be before the advent
> of most of the emissions controls. I'm just trying to help explain your
> observations.
>
> Good luck
>
> Les Myer
Les is absolutly correct in what he said.
I had a 75 Spitfire 1500 (bought new) it was a dog, after 11,000 miles
the 1500 blew up so I bought a good used 1296cc spitfire engine.
This was the same bore as the 1500 only with flat top pistons, twin SUs
and a better distributor advance.
This lower cc engine made that Spitfire go like it should.
Just for the record, I dumped the Spit and returned to Sprites, much
better car in the long run.
--
Frank A Clarici 3rd
Too many LBCs
Enjoying the DRIVE everyday
http://www.exit109.com/~spritenut
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