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TR4/4A Speaking of Webers - TR4 application question

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Wow, excellent information, all - and to think it is only because I've been bored and missing my TRs!

I noticed that Ebay U.S. just had a Cannon TR4 setup sell for a little over $1000 - I'd certainly like to beat that price, otherwise it is back to the thought on a TR4a SU setup. I noticed that the ebay one did have an added vacuum port tapped in it.

I stupidly passed quickly by the Phoenix booth at Stoneleigh a few weeks ago - though I did stop long enough to by a stainless heater bypass line. Their stuff looks good, and there are a lot of good opinions of their quality on the TR-Register forum. I don't think they have a dedicated web page, but Quiller does have at least a snapshot of a couple of configurations:
Phoenix exhaust pics

Oops, I did find their actual site, but it is only a one pager - looks like will do take direct orders:
Phoenix website

I will be in the hunt for best pricing on those as well - I have about 3 months before moving back and my wife hasn't realized how much money I'm about to let go - I think she's still enamored with the TR earrings I bought her.

Randy
 
TR4nut said:
I noticed that Ebay U.S. just had a Cannon TR4 setup sell for a little over $1000 - I'd certainly like to beat that price, otherwise it is back to the thought on a TR4a SU setup. I noticed that the ebay one did have an added vacuum port tapped in it.
Click to expand...

I do use a "Triumph Tune" intake manifold. The Cannon has to be reworked because it is smaller than the Carbs. As far I remember the intake diameter of the Cannon is 36mm. The head has 38mm and the carb 40mm, so happy grinding is needed ;-)
 
dual side drafts are definitely cool. but for power, the priorities should look like this:
1. this is definitely #1 -a good porting job on the exhaust port and combustion chamber.
2. a good cam upgrade (timed properly!)
3. a good header and exhaust system
4. compression increase
5. intake
some may disagree and put the cam first. the exhaust port is poor and combustion chamber. the intake port is large enough and just requires clean-up.
All the experts i have talked to recommend 45 webers with 34 or larger chokes for a "modified" engine.
however, you should look at your rev range and if you do not increase rev limit (and improve the crankshaft-required) then 40s are fine. one thing to note is that the tmw manifold is 45mm ID.
Rob
 
one other point,
the intake manifold and port should taper slightly IN from the carb to the valve. it is also fairly costly to get the initial tuning correct if the carbs you start with are wrong. get ones with the correct choke size at least. 30-32mm for bone stock engine. you had better plan on getting an msd type ignition system. you need a big fat strong spark, multiple spark best, for webers (one draw back you had better spend money on) otherwise you may never be able to tune them.
Rob
 
Camshafts, I feel, should be last on the list of power modifications. It is dependent on everything else. You make one change to the intake, exhaust, or anything that effects airflow, then you are going to need a new cam grind if you want the maximum amount of power. Otherwise, good info, and an even better thread.

Also, don't sell the SU's short. Properly tuned the SU's will really give the weber carb cars something to really worry about.
 
you will feel a cam change without anything else such as the exhaust system though. if the head is off for the porting, it makes sense to do the cam while things are apart,same with compression increase to 9.7-10.0. exhaust can come any time but the head should be first.
Rob
 
For a street to mild race motor you're correct. I'm really probally missing the whole point of this thread and thinking about a balls to the walls race motor.
 
The main advantage of a Weber carb is to handle a hot cam.
I run 310 degree on streets, go shopping with the car or visiting clients and the engine is idling smooth, not like a race engine.
They can be adjusted to every need of an engine with all the gadgets implanted.
 
Yeah, these British cars are unreliable at best /bcforum/images/%%GRAEMLIN_URL%%/wink.gif lol. Buzz has hooked up with one of the premier Mazda prep guys in the country. Those guys (Speedsource) build some VERY fast cars.

Both guys are VERY fast. Especially considering their ages.
 
I crew on the green & red Spitfire on the cover of the first book. It has a new owner now.
 
You are correct. It WAS a west coast car. The new owner lives in Maryland and had the car shipped here all the way from the L.A. area last fall. The PO works in the movie industry.

Quite a fast and well-prepared Spitfire.

And the driver is no slouch!

Crew is old and slow, though.
 
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