Ford Ka Rallycar .. Throttle plate size?

Competition engines and ancillaries - general discussion
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RedLexus
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Ford Ka Rallycar .. Throttle plate size?

Post by RedLexus »

Hello again all .. I have started rallying a Ford Ka , as built to the Ka championship rules when that was current . The engine is the fuel injected variant of the venerable Ford crossflow/pushrod 1300 cc , It has allegedly about 95 bhp . Running on 95 RON pump fuel with Silkolene Pro-Boost .it has a tubular manifold , sadly I don't know the compression ratio or the camshaft . The Throttle butterfly is a 42mm , with a taper from approx 75mm down to the smooth bore section around the butterfly .Breathing through a short run of pipe , from a large foam filter . The casting has a noticeable lip where the taper ends and meets the smooth bore section , and there is a step after the throttle plate too where the smooth bore finishes and it tapers out again . Also the butterfly screws are quite long , and butch , and the shaft is quite big , at a guess I'd say 7mm diameter .

Now is it worth while rectifying these minor faults?
The chassis feels like it needs another 15 bhp at least..There is the option of a 50mm Throttle body , but it's £180 , plus another £76 for the adaptor plate... And I'm not sure if the engine needs that size?
Due to cost I'm not going for ITBs , or Carbs.. And the reliability and smoothness of the current injection system is a bonus especially in the forests . The ECU is from what I gather , a MoTech , that I can get tuned to the engine on a friends Dyno . Anyone any suggestions , please? I will take some engine bay pictures and that might help . Thanks in advance .
Ford Sigma KA. GC_43
Guy Croft
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Re: Ford Ka Rallycar .. Throttle plate size?

Post by Guy Croft »

It won't be the throttle plate holding it back, see:

viewtopic.php?f=1&t=679&p=3330#p3330

GC
RedLexus
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Re: Ford Ka Rallycar .. Throttle plate size?

Post by RedLexus »

Thanks GC.. the numbers confuse me slightly , but I take it that it's large enough so . Anything to be gained from smoothing out the ridges?
Ford Sigma KA. GC_43
Guy Croft
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Re: Ford Ka Rallycar .. Throttle plate size?

Post by Guy Croft »

Maybe, always worth a try.

GC
RedLexus
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Joined: December 26th, 2007, 7:14 pm
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Re: Ford Ka Rallycar .. Throttle plate size?

Post by RedLexus »

I did so tonight...
Attachments
before , front
before , front
Escort and Ka 005 (Small).jpg (47.4 KiB) Viewed 6132 times
before , rear.
before , rear.
Escort and Ka 007 (Small).jpg (44.24 KiB) Viewed 6131 times
ground out lip/ridge
ground out lip/ridge
Escort and Ka 043 (Small).jpg (45.63 KiB) Viewed 6130 times
Ford Sigma KA. GC_43
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