TR6 HS6's on a TR6

[TheSearcherMan]

Hey, whatever happened to the guy who installed the HS6's on his TR6, and was going to put it on a dyno, been a month or so ago? Thanks

 

[LastDeadLast]

Was that me? I've got HS8s. I'm still here. I think I discovered a heat issue with the carbs. I've got the linkage all torn apart to get a heat shield made with for them. The carbs got so hot I couldn't touch them after a spirted drive and started to miss badly. To battle this problem, I designed a double-walled heat shield that I'm getting a local shop to cut out of stainless for me. Should be done next week.

You gotta pay to play I guess.

-s

 

[Brosky]

Shannon,

Why would you have such heat trouble with these carbs and not the triple ZS?

 

[LastDeadLast]

Two reasons me thinks. One, Since I can actually tune the carbs, I'm able to run the carbs leaner than before.. closer to optimum performance ranges rather than pig rich like it was with the tripps. And two, the design of the HS8's sort of lends itself to heat problems since the body of the carb body and the float bowl is linked by a unshielded feul line that is a few inches from the headers. Many of the HS carbs had heat shield from the factory that shielded the those connector fuel lines from engine heat.

It's an educated guess... but I can't find any other reason that it would act like it does. I've checked the carbs, fuel pump, fuel lines and electrical.

 

[Brosky]

That makes sense. I just thought that it would be a lot cooler with two SU carbs up there instead of all of the mass associated with the three ZS carbs. I oversimplified it and if it is leaner, it will be hotter.

Thanks and keep us posted. I'm still thinking about the Pirace cycle carb setup, but have yet to receive an answer from him about his recommendations from my email request last week.

Here I am, playing with these $$$ ideas in my head and I've only driven the car 20 miles in the last (5) weeks because of being involved in too many other projects. Two differently finished dash boards are sitting across the room staring at me wanting to be installed and a pile of gauge guts are sitting, all painted and neatly bagged on my workbench waiting for the gauge/dash project to come alive.

 

[TheSearcherMan]

Well, why did you use the 8's, when it seems most of the shops, 2, are pushing the 6's. What's the deal?

 

[LastDeadLast]

Well, why did you use the 8's, when it seems most of the shops, 2, are pushing the 6's. What's the deal?

My Momma always said I never liked to do things the easy way.

The irony is that I've been blessed with two boys that feel the exact same way. I now know why my dear mother is crazy.

But man, to hear those two big carbs howl at full throttle... I get goose bumps just thinking about it. :thumbsup: I've heard twin SU's, triple ZS's and the stock setup and nothing comes close.


-s

 

[Brosky]

Well, that is over half of the enjoyment of having multiple carbs, isn't it? Besides being eye candy as well, of course.

 

[LastDeadLast]

Well, I think I might have found a clue to my problem. I finally got around to hooking up a fuel pressure gauge. So I fire the old girl up and get her to operating temp. Fuel pressure is at 2 psi: perfect. I go about setting the timing and the idle. I look at gauge again and it reads less than 1 psi!!.

I checked for leaks: nothing. The car is at operating temp, but the carbs aren't hot to the touch. I turn the engine off and prime it manually, the gauge pushes up to 2psi as a pump.

The pump has been recently rebuilt, and I even took it apart a few days ago to make sure everything is as it should be.

Brand new filter, fuel line flows freely, what could be wrong with my pump?

I'm more confused than ever.

-s

 

[poolboy]

As long as the float chambers are staying full, the pressure should be adequate. Can you loosen the top of the float chamber a bit to see if they're full when the engine is running fast?

 

[Brosky]

You didn't rebuild it with one of those "red" diaphragm kits, did you?

 

[LastDeadLast]

As long as the float chambers are staying full, the pressure should be adequate. Can you loosen the top of the float chamber a bit to see if they're full when the engine is running fast?

That's the issue. I had "an incident" the other day that caused the car to just stop... I could barely to get it to idle but then finally nothing. I did remove a fuel line at the time and cranked the engine but nothing came out. Once I got the car home, I took everything apart (fuel pump, dizzy, carbs but couldn't find anything wrong with it until I let the car idle for a couple minutes at 3000rpm when the problem returned (unfortunately, I did not have a fuel pressure gauge at the time). I was thinking it might be an issue with the fuel lines or carbs getting too hot, but now that I have a pressure gauge, I'm swinging back to the fuel pump.

Any ideas?

 

[LastDeadLast]

You didn't rebuild it with one of those "red" diaphragm kits, did you?

I can't remember, why do you ask? :eeek:

 

[LastDeadLast]

It's the black diaphragm.

 

[Brosky]

Sorry for the late response. Several posts either here or 6-Pack have shown that the "Red" diaphragms are not reacting well to the current gasolines and are swelling and becoming soft in low mileage rebuilds. Hence the lack of pressure.

The pictures that I saw were not pretty.