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Optimistic

I've been considering a set of those, however; they cost as much as my car did.
 
Those are longer than 3" and it's engineered for the car, not just left over parts in someone's garage.
grin.gif
Besides, I was looking at the dual set rather than all four.

More like dual flatslides on a euro intake.
 
kellysguy said:
it's engineered for the car, not just left over parts in someone's garage.

How do you think it got "engineered" for the car in the first place.
 
This is really tried and true territory with the Tr Spitfire crowd. These are engineered.

My friend in the Portland Or area has some like this on his Spitfire, it goes like STINK!

From here:
https://www.triumphspitfire.com/carbchoices.html

mcginnisenginebay.jpg

and
mcginnisengine2.jpg
 
Thats why I gave up trying to find an appropriate set of MC carbs when I built my Datsun engine swap. Apparently a setup like that on 4 cylinder cars is popular. The carbs sell for the moon. We know theres plenty of them out there when you have 150hp on two wheels!! Lots of crashes!!
SU's are easier to tune anyway.

Kurt.
 
Morris said:
kellysguy said:
it's engineered for the car, not just left over parts in someone's garage.

How do you think it got "engineered" for the car in the first place.

They used parts out your garage? :hammer: :jester:

"Morris Enigeering, when your biggest hammer just doesn't cut it." :hammer: :jester:

Oh wait, that's my slogan. :laugh:

I don't think the 4 set will clear in the Midget.
 
The 1500 engine, even if balanced, is a long stroke unit that works best at low RPM engines (under 6K), unless you are willing to do extraordinary maintenance on it (ie-new rod bearings and reground crank yearly or more).

So putting carbs that require very high RPMs to "work" is sort of maximizing the weak area of this engine.

I raced a partly balanced 1500 and used a "fast-road / torque" cam with a single 2" bike carb and custom manifold. It worked well and had similar pep to my current 1275 (but felt different due to "short shifting" at 6000). The twin SUs are a good setup too.

If you want to built a high RPM Triumph engine that can actually take advantage of those carbs (and not expire prematurely), you need to build a 1296.

Unless you're just using 4 carbs for show. :wink:
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
If you want to built a high RPM Triumph engine that can actually take advantage of those carbs (and not expire prematurely), you need to build a 1296. [/QUOTE]

Come to think of it that's what my friend has, not the 1500.
 
While I obviously admire that kit, those carbs where "engineered" for a motorcycle. The fellows that put together the kit did a very good job, but I guaran-dang-tee you that the project started with one of the guys at Pirace looking at a pile of old bike parts he had laying around the garage. The kit did not just magically spring from his brilliant mind. And while I know that the guys at Pirace are waaaaaayyyy more skilled and knowledgable than I am, they got that way by trying to implement new and crazy ideas... like putting motorcycle carbs on a spitfire.

And what is "engineering?" Does a modification only qualify as "engineered" if you used a slide rule at some point in the process? I have 3D computer models of various ideas for intakes based on the best math available in intake design. Does that count as engineering?

Sorry to hijack your thread JP, but I am frustrated with Kellysguy's dismissive and patronizing attitude to everyone's ideas, when he himself is no stranger to... erm... "unusual" car mods. Anyone here who has designed, built and implemented a computer controlled injection and ignition system for his car is welcome to accuse me of using a big hammer (I guess that's you Glen) but as for you Billy, I would appreciate being treated as at least an equal.
 
Did I start this by mentioning runner length?
I guy named Bob Tooke (Sp?) made a port injection system for his 1500. He documented the process on the web. It didn't work very well using short runners. He then built a custom manifold with as long as runner as possible. I think he decided that the car had about the same power as with the original twin SU setup (Bob lives in the UK), but it burns cleaner and gets slightly better mileage.

That is all I know about runner lengths on a FI 1500 engine.
 
Not all bike engines are high revving, and in my experience of 600's and 750's they all pull cleanly from 2000RPM on up. They are not designed to be high RPM only devices, if the were they would never pass Federal emission testing. Most big bore bike engines spend the bulk of their lives on the street where they happily run between idle and 6000 RPM. You just cannot run a Hyabusa or other monster bike at high rpm very often or for very long anywhere but on the track,or wide open road.

The use of bike carbs on car engines over in the UK is a well trod path. Lots and lots of forum posts about successful installations on all sorts of engines. We here in the US are way behind that curve.
 
I have read his website and communicated with him personally. He is a great guy. And your (and Billy's) comments on runner length are totally legitimate.
 
Doesn't runner length include the length of any intake trumpets or velocity stacks? If so then one could use a shorter intake manifold to keep the carbs in a convenient location under the hood and simply add stack length to get the optimum distance.
 
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