Date: Wed, 17 Nov 93 22:32:37 EST
From: Randy Wilson <randy@taylor.wyvern.com>
Subject: RE: Spitfire 1500
Tony wrote:
>Hello all, I've got a '77 Spitfire 1500 with Weber DGV carb and headers on
Then Randy replied:
> You already have more carb than the 1500 can use. Indeed, enough that getting
>the car to accept full throttle at low rpm is a problem. I am not saying the
>DGV conversion is a *good* thing. The jetting as supplied and the manifold
> That said, you're not going to make any significant performance gains by
> changing to a different carb set up. Changing to the twin SU/Stromberg or
> a single sidedraft Weber/Mikuni/Dellorto may gain you something in drivability
> but not much in terms sof raw power. 70's cars were seriously detuned to meet
Sorry Randy but I would have to seriously disagree with here :
1 year ago I took the race engine out of my 1500 Midget and fitted a STANDARD
1500 engine from a 1979 Midget. The engine had aout 46,000 miles, has good
compression, excellent oil pressure and burns no oil. This was going to
be a temporary engine, while I stripped and inspected my race engine.
I fitted a Weber 45 (?) DCOE carb, a 4-branch manifold, Lucas comp. dizzy,
and removed the fan (I have an electric fan). Initially the carb was way
out of tune (as it had been taken from the race engine - thus the jetting
was way off). After rejetting the carb and experimenting on the road, I finally
found the correct combination of jets.
The car felt great ! throttle response was instantaneous, power above
2500 rpm was strong, the engine would rev beyond 6500 rpm (although somewhat
noisy !)and fuel consumption was about 26mpg.
A few days later I did some performance tests to see what the ACTUAL difference
was. I have an ALFA B rally computer which measures 0-30, 0-60 and 1/4 mile
times which it calculates from sensors attached to the wheels.
I don't remember the 1/4 mile times but the fastest 0-60 time was
12.1 seconds (I think the standard Midget was around 15-16 seconds), which
showed that I had boosted the power of the engine quite considerably by making
the 4 changes I have described earlier.
Okay so the Weber DGV is not as good a performance carb as the DCOE, but I think
ANYTHING is better than the stock ZS. I have a DGV carb for the Midget which
I may swap and see what the difference is, But I remember when I first fitted
the DGV and threw away the ZS, the performance increase was substantial.
To the original poster :
If you are thinking of getting a Weber, and want power - get the DCOE. You
should be able to find these carbs (used), if you hang around the race people -
they always have a spare Weber lying around !!!
Gerry
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