The all-new Front Page News Feed is now live   Read the announcement
TRExp

TR6 Tech Forum

TR6 S.U. Carb Conversion

Moss Motors
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor

Bob DeShane Avatar
Port Perry, Ontario, Canada   CAN
Is there anyone out there that can provide advice or instruction/drawings of required modifications to the stock throttle linkage on a TR6 in order to accommodate the Burlen S.U. Carb Conversion?

. Hide this ad & support a small business by becoming a Gold Supporting Member
Was this post helpful or interesting?
Yes No Thank
gbtr6 Avatar
gbtr6 Perry Rondou
Titletown, WI, USA   USA
Not familiar with these, but if it’s twin HS 6’s, on the stock manifold, no modification to the linkage needed. You may have to rotate the float bowls. Not hard to do.

Perry

Was this post helpful or interesting?
Yes No Thank
yycdave Avatar
yycdave Dave More
Calgary, AB, Canada   CAN
1976 Triumph TR6 "Miles"
Here’s a view of the setup on my car. As stated no modifications should be needed to the linkage. One thing to note is that the choke cable is connected to the front carb only with the rear choke being operated through the shaft linkage. The rear cable is there but just hanging loose.

Another thing to pay attention to is the venting of your valve cover to the intake ports on the carbs. Failure to do so will result in crankcase pressure buildup resulting in leaks around the valve cover, and in particular on the driver side by the engine number stamping.

Also important is the routing of the float bowl overflows which sit right above the exhaust manifold (!). Mine are routed to exit at the front of the car by the canister to prevent any unintended conflagrations!

Hope this helps



Cheers,
Dave

76 CF58310UO



Edited 1 time(s). Last edit at 2019-03-06 11:08 PM by yycdave.

. Hide this ad & support a small business by becoming a Gold Supporting Member

Attachments:
carbvent.jpg    53.9 KB
carbvent.jpg

carbvent (2).jpg    50.2 KB
Sign In or Register to view this photo
Was this post helpful or interesting?
Yes No Thank
Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, OR, USA   USA
1980 Triumph TR7 Drophead "The Great Pumpkin"
1980 Triumph TR8 "Wedgie"
In reply to # 1600433 by Bob DeShane Is there anyone out there that can provide advice or instruction/drawings of required modifications to the stock throttle linkage on a TR6 in order to accommodate the Burlen S.U. Carb Conversion?

Bob:

Any particular reason you wish to do this? There is no performance advantage to SUs, although they are simpler and there is always the "Gee-whiz" factor when you raise the hood at your local park and shine meet.

The Zeniths get the job done, and getting them rebuilt by a pro will cost you less than a conversion. I was very happy with my Zeniths after a rebuild and a tune up - and I had modified my engine extensively.

Vance



1980 Platinum Metallic TR8, frame off restoration, complete.
1980 Vermilion TR7 Sprint replica, in progress.

Was this post helpful or interesting?
Yes No Thank
Bob DeShane Avatar
Port Perry, Ontario, Canada   CAN
Thanks Vance. Yes, there is a reason and that is that Strombergs are generally garbage. I have had a sportscar/race shop for many years and although you can make Strombergs work almost as well as an S.U. on their very best day, you just never quite get there. Additionally, they are so very prone to issues with fuel and additives and have a very limited ability for tuning as compared to the S.U.. That being said, if you like them, that is just fine.
In this case, I supplied the Burlen Conversion to a customer for installation by the shop that he uses, which unfortunately has now closed. He is now contemplating doing the install himself and he is without much experience, knowledge or "McGivor-ability". Accordingly, in order to help him, I was merely looking to see if anyone had written instructions as they are not supplied and having them in hand will likely save me a lot of time on the telephone.
Never the less, thank you for your willingness to share your opinion.

Was this post helpful or interesting?
Yes No Thank
POW Peter Wirth
HEBRON, NH - New Hampshire, USA   USA
In reply to # 1600841 by Bob DeShane Thanks Vance. Yes, there is a reason and that is that Strombergs are generally garbage.

OH! I bet that stung! spinning smiley sticking its tongue out Kind of like "Holley rules, Edelbrock drools!"

Was this post helpful or interesting?
Yes No Thank
gbtr6 Avatar
gbtr6 Perry Rondou
Titletown, WI, USA   USA
Th SU’s are generally a ‘plug and play’ operation. You even use the stock linkage. Nothing complicated. Zenith Strombergs work very well when properly set up. That said, i have SU’s and they are very good too. Easy to setup and maintain.

Perry

Was this post helpful or interesting?
Yes No Thank
fordfiesta Doug T.
Cambria, CA, USA   USA
Slightly-scary engineering of late TR6 cars with Strombergs: each carburetor float bowl has a leak-prone plug in the bottom, right above the exhaust system. Something of a recipe for a conflagration, as my experience on my '75 was not merely a seepage of gasoline (a common small leak) but more like a gusher. The cause was a perished float bowl plug seal, which was repaired by a new seal coated with hylomar-based (gas-proof) sealant when it was installed. I have also seen Stromberg float bowl bottoms without the hole for the jet-adjuster plug, but am not sure if they have the same screw pattern as the ones on a TR6. Others may know.



Edited 2 time(s). Last edit at 2019-03-12 11:36 AM by fordfiesta.

Was this post helpful or interesting?
Yes No Thank
poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
OK. OK.. let's at least stick to the facts....the 250 and none of the TR6's had ZS carbs with jet adjusters thru the bottom of float chambers..
I should add the the HS6 SU can be leakers too....their jet assembly and off set float chamber connections.
The earlier statement about "garbage"..obviously comes from someone who doesn't know much about ZS carbs....fooled by the simple need to replaced perished components.



ZS carb repairs
kencorsaw@aol.com

Was this post helpful or interesting?
Yes No Thank
Marksg1 Avatar
Marksg1 Mark Greenbaum
Evanston, IL, USA   USA
1976 Triumph TR6 "Nigel"
I'm not switching from Z's but I believe instructions are on the Moss site.



I love the smell of hydrocarbons in the morning.

Was this post helpful or interesting?
Yes No Thank
titanic Berry P
Albany, OR, USA   USA
The ZS and SU carbs are pretty much 2 flavors of the same product and both have some features that are neat and not so neat. The choke mechanism on the ZS is easier to operate and less prone to sticking. The ZS has steel bushings&seals for the throttle shaft and should never require rebushing.
Disadvantages might be the biased needle, which tends to wear needle&jet, the needle adjustment mechanism, which tends to leak, and the location of the float bowl, which makes it difficult to deal with a clogged needle valve without removing the carb, also the o-ring in the float chamber plug in prone to leak.. Also, the temp comp. and throttle bypass valves, which can be troublesome, but easily disabled.
The early SUs (pre-emission) HS6s have fixed needles , easily adjustable jets, and the external float chambers that allow access to the needle valve.
I changed to SUs many years ago, gathering the parts and experimenting with different needles, am satisfied with the results. But if you are just having problems with the ZS carbs, springing for the SU conversion doesn't make sense. Having the stock carbs rebuilt is much cheaper.
Berry

Was this post helpful or interesting?
Yes No Thank
1975TR6 Avatar
1975TR6 Phillip Bridger
Calgary, AB, Canada   CAN
Bob. I've a near identical set up as Dave Moore for my 1975. It's about as typical as it gets and pretty reliable with not too much fidgeting. There was no change to the linkage required although I do see some tighter clearances... but works well. Phill

Was this post helpful or interesting?
Yes No Thank
. Hide this ad & support a small business by becoming a Gold Supporting Member

To add your reply, or post your own questions




Registration is FREE and takes less than a minute!


Having trouble posting or changing forum settings?
Read the Forum Help (FAQ) or contact the webmaster