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New engine progress, Thursday evening

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"This was an ideal setup on an MGB with a Weber.", Interesting quote from you. Oh, and Alan, I appreciate you sharing your dyno results, wish others would do the same.
 
A friend had triple SU carbs on his GP intake. Worked well. Also, last years NO car show had a fella with super-tuned trip Weber DCOE carbs. I was embarrassed how easily his started and idled. But his 6 cylinder coupe was set up for rallye (which he did in Africa) and was, well, super tuned.
 
As Bill says, Triple SU's will fit just as easy as triple ZS's on the GP manifold. The ram air unit for ZS's won't fit them but GP makes a ram air box for the SU's as well. The HS-6's, with their side mounted float bowls can be a tight fit though. The throttle linkage is different too so that would also need to be addressed.

Neil Revington (Revington TR) was in Fort Collins a few years ago and was looking at my TR6. He thought the ZS's were fine, agreed that the HS-6's would be a tight fit but do-able. The hot ticket in his opinion was to go with Triple HIF44's since they have integral float bowls like the ZS's.

I originally planned to use triple SU's on mine but at the time the cost to totally rebuild the SU's tipped the scale. Typically, it is easier for a TR6 owner to do the Triple ZS option since they already have two to begin with.

I did originally have an issue getting the stock needles to work with my set up. Altitude was the killer in this case. Joe Curto helped pick the right needles for my situation. They do happen to be from a Jaguar, a V12 E-Type with an automatic transmission to be specific.
 
SU would be the way to go, However, I am being told you can get 140 HP off 2 SU's by someone in the Fatherland, ie GB. But, then again, to me, its all about driveabiliy, not just HP. I have yet to see any dyno results from ZS carbs, would like to see some, other than Kasners. That said, I spoke to someone who got a 135 from his 6 on Webers, and he was working for Weber at the time I believe. What this means is, to get 140 from 2 SU's, you would need a more radical cam, and higher compression, which means no driveablilty. He also said he wouldn't want to be driving his Weber car at 7000 feet. So, I guess the rockies would be out of the question.
 
Maybe the answer is........1 carb per cylinder!

gt6induction1.jpg


Here's a place https://www.prirace.com/carbs.htm that adapts motorcycle carbs to various Triumphs. I met a guy at the CT Triumph Show last fall that was running duel Mikuni's and loved them.

Now we're officially way off topic :square:
 
TheSearcherMan said:
SU would be the way to go, However, I am being told you can get 140 HP off 2 SU's by someone in the Fatherland, ie GB. But, then again, to me, its all about driveabiliy, not just HP. .....

.....He also said he wouldn't want to be driving his Weber car at 7000 feet. So, I guess the rockies would be out of the question.
Click to expand...

Other than easier tuning and larger needle choice, I have yet to see anything that would prove to me that an SU is capable of flowing more than the comparable ZS. If you can tune the ZS's in with a CO meter, the extra needle choice advantage of the SU takes on less importance. The SU's are simpler and you don't have to worry about torn diaphragm's.

I'd be happy to show you a dyno result if it was accurate, the only one I have is with the wrong needles and a worn out distributor. So it really wouldn't be a valid comparison. Even with a horribly wrong mixture and very poor timing control I still put down almost 120hp at the rear wheels. The torque curve was nearly flat from about 2800rpm to 5800 rpm as well.

As far as crossing the Rockies with Weber DCOE's, you could still do it if you wanted to re-tune your Weber's after about every 2000 feet change in elevation. Wouldn't that be fun, especially since you would also have to change your choke size. That, in and of itself, is why I won't put Weber's on my TR6. Both SU's and ZS's handle the elevation changes much better. Since it is very easy for me to go from 5,000 feet to 10,000 in feet in one hours drive time, that is a very important factor. Fuel Injection is on my to-do list. Looking at a few different ways of doing it. None of them are inexpensive.
 
Well, what you meant to say is, the test was accurate, but the car wasn't up to snuff. You left out 2 very important things, one you can sorta get around the other you can't. The one you can't get around is the temperature compensator. Sure, do what they told you to do, disable it by screwing it in, then, on a warm day, you will run rich and load up at idle. Now don't tell me this ain't so, cause I know from my own experience it is. As far as the bypass is concerned, I have my own idea's about what that really does, but I blocked mine off, and there is a sacrifice. Put your car on a dyno with an air/fuel indicator, I don't think you will ever get the mixture right, you think it's right now, but do you really know? Around here a dyno test is about 60 bucks for 3 pulls, you show me 120 HP at the rear wheels with the right mixture across the range,from 3 ZS's and I'll pay you the 60 bucks, hows that? Heck, I'll go one better, you show me 110 HP with the mixture close across the range and I will pay you the 60 buck dyno fee. Ah, this includes idle. Free dyno test, can't beat that. It ain't going to happen is it? You got a paypal account?
 
Well your right that the test was accurate. What I meant by not accurate was that it wasn't representative of a correctly tuned system. Yeah my temperature compensator's are effectively disabled, but even if they weren't I'd still have an issue with loading up under prolonged idle. The high lift cam sees to that. Enough so that it would happen with Weber's or SU's as well. It won't even idle smoothly below 1100rpm. Please, do tell what you think the bypass does and what you sacrifice and/or gain by blocking it off.

When it was on the dyno, it did have an air fuel indicator sniffing away at the exhaust. That's how I knew the mixture was horribly wrong. That's also how I knew the needle profile was wrong. Once it was past the 'just off idle' segments, where the profile was all wrong, the mixture was very even all the way to 6000 rpm. It was also extremely rich but it did hold a steady mixture.

I know where your going, your trying to prove that fuel injection is better than carburetors. Any carburetor on a performance engine will have difficulty fulfilling your stacked bet. Even SU's or Weber's! Add the 'drive-ability' into the equation and EFI is the only way to go. Notice I said EFI not PI. The PI systems tend to run rich at idle, specially with your favorite CP series camshaft that had idle issues as well.

If you want EFI than stick with it and go for it. You don't have to disparage anyone using ZS's (two or three). Just because someone told you SU's were better. I've worked with ZS's, SU's and Weber's. They all have their pluses and minuses. Eventually I will inject my car because, yes, it is the best compromise between power and drive-ability. But just like any other form of tuning, it is based in compromise. There is no golden egg.
 
So, keeping the GP manifold would allow for three ITB's. I wonder how it would compare to three of Rick Patton's throttle body conversions. :computer:
 
Now that is porn and I have to leave the computer for a minute. :jester: :devilgrin:

I have to have that!!!
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I wonder how it would compare to three of Rick Patton's throttle body conversions.[/QUOTE]

I plan to visit BobbyD in CT one of these days, probably at the Harkness Brits by The Sea Day, and compare notes on this topic. Rick is working on a conversion package for the triple ZS as we speak. Maybe it will be next years project.
 
TheSearcherMan said:
I like that. I don't see why Rick Pattons deal won't work if you use a Megasquirt. Anybody know?
Click to expand...

I think Rick is trying to do it as a 'plug & play' type system. Megasquirt would probably work just fine.
 
Hey Alan, it's early in the AM and I just got a great idea, why don't you sell me your manifold, for $50-75 bucks, and get you one of the extrudabodies? Sound like a good idea to you? (PS) just kidding!
 
Paul:
My car is the test vehicle for Rick Patton's TBI conversion for the tri carb set up. You can have the 1st kit in production.

A guy in Colorado did a tri carb TBI for a Healey. I tried to contact him but he never returned the emila. BobbyD has the info.
 
Thanks Al, I'm sure that will make my wife very happy.
 
Rick's TBI conversion will work just fine with MegaSquirt or any other ECM that you're skilled enough to "program". For simple folks like me......I needed a plug & play installation. He offers the option of buying the whole kit or just the adapters and TPS. There's more info here https://www.pattonmachine.com/Pricing.htm

He's sold a number of adapters that have been fitted to a wide range of cars. My personal favorite is the Land Rover from Finland though there is a "Z" that will be at LeMans this summer with his kit. The last car on his Customer Car page is a TR6 with MegaSquirt as the ECM. https://www.pattonmachine.com/CustomerCars.htm
 
TheSearcherMan:

You have found the car to respond to your search. Up here, a dyno session will cost $100. I will accept your $60 and add the $40 to show that the tri Stromberg is developing more than 110 HP. I do have a Paypal account. I will call for a dyno appointment, usually a week out. Which dyno do you want me to use? There are two here; Mustang (wheels/tires on roller) and the DynaPack (replaces the wheels). Since you are paying, you choose.
 
The offer wasn't made to you, your car has alot more modifications. Remember the other part, mixture in the ballpark, including idle. I may still do it, but I am not paying for your previous dyno test. Also, I will want to see the charts, showing , HP, Mixture, and Date.
 
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