• Hi Guest! Being a Paying Supporter is NOT a requirement to participate at BCF. However, subscribing will help ensure we can continue to serve the LBC community for years to come. If you enjoy BCF and find our forum a useful resource...Please consider supporting us by **Upgrading**
    (PS: Subscribers don't see this banner)

SU Carb Heat Shield


Jedi Hopeful
Can anyone speak to the pros/cons of having heat shields installed on their TR3/TR4 SU carburetors? I'm thinking about doing this, think it certainly couldn't hurt, but dont want to needlessly blow $35 on something that adds no real value. I'm not a racer, and I don't drive my car on scorching days. Thanks for the input!


Jedi Hopeful
I don't really think it's necessary. I drive my '4A on hot days and haven't had heat related fuel issues.

Don Elliott

Obi Wan
I would suggest that you don't need one. I don't have one on my 1958 TR3A. I don't think Montreal is any cooler than Maryland on any given hot summer day.

I had several TR owners advise me to install a heat sheild back in 2007 when I was getting a lot of stalling, stuttering and lack of fuel flow to my carbs on hot summer days - such as when I drove 1550 miles round trip to VTR in Valley Forge PA. I assumed (as did many others) that this problem was caused by vapour lock resulting from the 10% ethanol added to gasoline in USA. I later changed out a 51-year old rubber hose feeding the float bowls and I was told to add 4 oz. of Marvel Mystery Oil to the gas tank every time I fill it up. I have done this and all the fuel issues have been resolved. Sice then, I have driven over 7,000 miles.


  • 18256.jpg
    83.6 KB · Views: 205


Jedi Knight
I had one on my '59 TR3. When I needed to service something (don't remember what, but it must have been on the carb side of the motor) it was so much in the way that I had to remove the carbs and heat shield to proceed with my work. The carbs went back on, but the heat shield didn't. IF, it's very hot, AND the car has only had a short sit since the last drive, SOMETIMES it stumbles a bit, for about 20 seconds after restart. I haven't felt driven to replace the heat shield.


Don, re. your Toronto-to-Maryland temperature reference, here is a rule-of-thumb I read years ago:

<span style="font-weight: bold"><span style="font-size: 23pt"><span style="color: #CC0000">70 MILES</span></span></span>

For ever 70 miles north or south, the average daily temperature varies by ONE DEGREE farenheit. When you think about it, it makes sense.


Great Pumpkin - R.I.P
TR3BGeorge said:
For ever 70 miles north or south, the average daily temperature varies by ONE DEGREE farenheit.
Of course, that's only a very rough guide. Local conditions can make it vary considerably. For example, Los Angeles is typically warmer than San Diego even though we are roughly 100 miles farther north. And of course, Death Valley, famous for being the hottest place in North America, is another 100 miles north from here.
Similar threads
Thread starter Title Forum Replies Date
J Bj8 intake manifold to heat shield to carb gaskets Austin Healey 4
GTP1960 TR2/3/3A Carb. Heat shield location? Triumph 11
C Correct color of carb heat shield, starter, and generator? Austin Healey 12
M Making a manifold/carb heat shield - any suggestions? Spridgets 14
KVH Carb Heat Shield Installation Triumph 2
D Carb Heat Shield Spridgets 12
19_again Carb heat shield MG 7
Brosky Goodparts Triple Carb Heat Shield Triumph 16
Steve P. '78 Midget carb heat shield? Spridgets 1
LastDeadLast Stainless Heat Shield for Triple Carb Manifold Triumph 7
jerrybny Carb Heat Shield Triumph 5
Lin carb heat shield Austin Healey 1
M Heat-related carb issue on BN1 Austin Healey 7
M Better carb heat shields to deal with vapor lock? Spridgets 18
J are the carb heat shields worth it? Triumph 29
Musicman A Question About Carb Heat Shields Triumph 5
M TR2/3/3A Paltech SU Carb Rebuild--Problem Triumph 3
RGK TR5/TR250 SU carb ID help Triumph 6
Healey Nut Tri-Carb Throttle Controls Austin Healey 3
jlaird MGB V6 carb help MG 14
71TR6 TR2/3/3A TR3A SU Carb rebuild opinions requested Triumph 12
E MGB SU CARB OIL 1965 mgb MG 3
Michael Oritt SU H6 carb for Le Mans--order of assembly of fuel bowl lid Austin Healey 2
D Tri carb: order of installation question. Austin Healey 5
Lotuswins Wanted TR4 H6 rear carb body Triumph Classifieds 4
E MGB SU carb air cleaners MG 10
Healey Nut Tri-Carb Project Austin Healey 42
doc50 For Sale Zenith carb, fits many cars. Other British Classifieds 0
tahoe healey Dumb carb question Austin Healey 23
jfarris TR2/3/3A Happy with my Paltech Carb rebuild Triumph 6
2 TR2/3/3A SU carb. Acts like an expansion valve ! Triumph 10
dbenichou289 TR2/3/3A SU carb linkages Triumph 2
CLB62 1962 BT7 Tri-Carb for sale on BaT Austin Healey 2
O HD8 carb on Healey 3000 Austin Healey 62
dbenichou289 TR2/3/3A Carb Sealing Ring Triumph 6
R TR2/3/3A Carb throttle return spring tension Triumph 2
drooartz MGB Troubleshooting Mikune carb MG 33
T TR6 TR6 Carb Gasket Sealing Triumph 1
HealeyPassion AH Carb Access panel Austin Healey 24
P Carb Help - Car idle slows and dies after being run for a while Austin Healey 14
Michael Oritt SU H6 carb question Austin Healey 5
T TR6 Carb. Float Chamber Fix Triumph 5
Editor_Reid H6 Carb Mounting Austin Healey 4
T TR6 Carb Vacuum Port- TR6 Zenith-Stromberg Carbs Triumph 2
K TR2/3/3A S U Carb Chambers and Pistons Triumph 1
K TR2/3/3A Auxillary Carb Return Spring in More BS about TR's. Triumph 0
pbraun For Sale Weber downdraft Carb & manifold Spridgets Classified 3
P BJ7 HS6 Carb Baseline Setting Austin Healey 10
Patrick67BJ8 HD8 Carb Repair Austin Healey 15
M Wanted Twin carb manifold for 1500 Midget or spitfire Spridgets Classified 0

Similar threads