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Radiator Shroud
- Thread starter Tomster
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Simon TR4a
Jedi Knight
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I have never driven my car without one, so cannot say how much difference it makes from experience. I have no problem with the electric fan being in front of ther rad, they should not normally need maintenance and the shroud could be removed if necessary.
Simon.
Simon.
On my TR3A I noticed an improvement in the cooling once I put the shroud on the car. I think the the vertical rad and the horizontal opening in the apron the shroud gives a marked improvement in airflow through the rad. Without it there is just too much of a flankiing path for the air.
Bruno_69z28
Senior Member
Offline
It helps during hot weather to funnel more air throught the radiator.
Bill
Bill
Guys:
My 250 came without one & I am considering making one up with some sheet alum from the local supply house. I see the spots along the top of the front cowl where the speednuts would go. My question is how are the sides & back attached? Anyone got a detail or photos?
My 250 came without one & I am considering making one up with some sheet alum from the local supply house. I see the spots along the top of the front cowl where the speednuts would go. My question is how are the sides & back attached? Anyone got a detail or photos?
jerrybny
Jedi Knight
Offline
From everything I have read it is supposed to be there to help direct the air flow thru the radiator. Without it the air flow will take the path of least resistance. which in this case is up and over the rad and around it. A very worthwhile investment. If possible get the plastic kind. It will last a whole lot longer than the cardboard type. /ubbthreads/images/graemlins/cheers.gif
kodanja
Obi Wan
Offline
I purchased an aluminum shhroud for my TR6 on ebay.
there very nice but a bit over priced for what the are.
Had I known they were so simple, I would have gotton some aluminum and prefab it myself.
They attach at the top of the grill with the stock holes for the cardboard shroud. as far as I can tell they have no other attachment bolts.
check out this link https://images.google.com/imgres?imgurl=h...6lr%3D%26sa%3DG
there very nice but a bit over priced for what the are.
Had I known they were so simple, I would have gotton some aluminum and prefab it myself.
They attach at the top of the grill with the stock holes for the cardboard shroud. as far as I can tell they have no other attachment bolts.
check out this link https://images.google.com/imgres?imgurl=h...6lr%3D%26sa%3DG
Alan_Myers
Luke Skywalker
Offline
Hi,
The TR4 and later definitely need the shroud in place to keep air flow from "escaping" around the rad. Without it, the cars are far more likely to overheat. Due to the shape of the air intake, lack of a shroud is a little less critical on TR2/3 (but still helpful). Beginning with TR3A "wide mouth" design, it got more important.
TR4 used a one-piece shroud that attaches via 3 spring-type screw clips (I dunno exactly what they are called) across the top of the valance and two more on either side of the "mouth".
Later cars used slightly different arrangement. I think your 4A has a 3 piece shroud. By the TR6 the shroud was much wider and more sharply angled (But can be made to work on TR4, etc. In fact, some years ago Vicky Brit sent me a TR6 shroud marked "TR4". I used it with some slight mods, see below.)
Original shrouds were "fiberboard", with a black finish. These disintegrate pretty quickly.
There are plastic replacements now available that are much better, although not quite original in appearance.
Or, make your own out of sheet aluminum - or sheet plastic, if you can find it locally. I riveted together a homemade aluminum one and used it for many years. The original, tired fiberboard one was used as a template. The aluminum shroud worked fine, but eventually cracked and got dented up. Because it was more rigid, it was more difficult to install and remove, too.
I ended up reinforcing the plastic "TR6" replacement with an internal, aluminum brace. Without that, it sagged all on it's own, blocking an inch or two at the top/front of the radiator. I can't imagine how much of the rad would have been blocked by it eventually, when the plastic got hot under the hood and sagged even more! I also riveted two additional alu brackets on the sides, so that it can be attached to the front valance. There was no provision to attach the sides on this particular shroud (I don't have a TR6 to check, maybe that's is normal).
The later shrouds aren't as deep (valance-to-radiator) as the early TR4 ones: about 1-1/2" less. This is actually useful, if a thicker custom radiator is being used, or if the radiator is moved forward to make way for a puller fan.
No, in fact the smaller 12" pusher/auxiliary electric fans that most vendors offer will fit just fine inside the shroud, where it will be pretty well hidden so the engine compartment looking relatively original. However, before installing one, see if the shroud alone doesn't cure any tendency to overheat. A 12" fan is generally more than enough, if used in this configuration. Keep in mind that a pusher fan like that blocks some air flow all the time, just isn't as efficient as a puller fan (which might be larger, I've got 14", some have installed 16"). There is some redundancy with the original fan on the engine, which might be good. But the electric fan motor is more exposed to the elements, out in front of the rad, and the original crankshaft-mounted fan puts some drag on the engine all the time.
Anyone having overheating tendencies probably should not consider an electric fan as a solution, by itself. If there are other problems, IMHO they need to be addressed first, then the elec. fan is added "for extra insurance".
My TR4 simply never overheated on me. That was with the stock, 4-blade fan, alu shroud in place and original "long neck" rad (without the crank starter hole). That was at high altitude and with increased compression, headers, etc. Even had the very "wrong" non-sleeved thermostat installed. Summers in Colo. were often 90+, sometimes 100+ degrees, too (it's a "dry heat").
Hope this helps!
/ubbthreads/images/graemlins/cheers.gif
The TR4 and later definitely need the shroud in place to keep air flow from "escaping" around the rad. Without it, the cars are far more likely to overheat. Due to the shape of the air intake, lack of a shroud is a little less critical on TR2/3 (but still helpful). Beginning with TR3A "wide mouth" design, it got more important.
TR4 used a one-piece shroud that attaches via 3 spring-type screw clips (I dunno exactly what they are called) across the top of the valance and two more on either side of the "mouth".
Later cars used slightly different arrangement. I think your 4A has a 3 piece shroud. By the TR6 the shroud was much wider and more sharply angled (But can be made to work on TR4, etc. In fact, some years ago Vicky Brit sent me a TR6 shroud marked "TR4". I used it with some slight mods, see below.)
Original shrouds were "fiberboard", with a black finish. These disintegrate pretty quickly.
There are plastic replacements now available that are much better, although not quite original in appearance.
Or, make your own out of sheet aluminum - or sheet plastic, if you can find it locally. I riveted together a homemade aluminum one and used it for many years. The original, tired fiberboard one was used as a template. The aluminum shroud worked fine, but eventually cracked and got dented up. Because it was more rigid, it was more difficult to install and remove, too.
I ended up reinforcing the plastic "TR6" replacement with an internal, aluminum brace. Without that, it sagged all on it's own, blocking an inch or two at the top/front of the radiator. I can't imagine how much of the rad would have been blocked by it eventually, when the plastic got hot under the hood and sagged even more! I also riveted two additional alu brackets on the sides, so that it can be attached to the front valance. There was no provision to attach the sides on this particular shroud (I don't have a TR6 to check, maybe that's is normal).
The later shrouds aren't as deep (valance-to-radiator) as the early TR4 ones: about 1-1/2" less. This is actually useful, if a thicker custom radiator is being used, or if the radiator is moved forward to make way for a puller fan.
No, in fact the smaller 12" pusher/auxiliary electric fans that most vendors offer will fit just fine inside the shroud, where it will be pretty well hidden so the engine compartment looking relatively original. However, before installing one, see if the shroud alone doesn't cure any tendency to overheat. A 12" fan is generally more than enough, if used in this configuration. Keep in mind that a pusher fan like that blocks some air flow all the time, just isn't as efficient as a puller fan (which might be larger, I've got 14", some have installed 16"). There is some redundancy with the original fan on the engine, which might be good. But the electric fan motor is more exposed to the elements, out in front of the rad, and the original crankshaft-mounted fan puts some drag on the engine all the time.
Anyone having overheating tendencies probably should not consider an electric fan as a solution, by itself. If there are other problems, IMHO they need to be addressed first, then the elec. fan is added "for extra insurance".
My TR4 simply never overheated on me. That was with the stock, 4-blade fan, alu shroud in place and original "long neck" rad (without the crank starter hole). That was at high altitude and with increased compression, headers, etc. Even had the very "wrong" non-sleeved thermostat installed. Summers in Colo. were often 90+, sometimes 100+ degrees, too (it's a "dry heat").
Hope this helps!
/ubbthreads/images/graemlins/cheers.gif
.jpg)
Don Elliott
Obi Wan
Offline
The air deflector in the TR2 and TR3 is the metal work part of the front valance grille opening. When they introduced the TR3A with the wide mouth in late 1957 they had no problems till it got hot in the summer of 1958. I bought my TR3A brand new in May 1958 and it didn't have a shroud. Dealers later installed them if a customer complained. The factory started to put them in some time in mid-1958. They really help. After all, let's think about it. The air would rather take the path of least resistance and go around the sides of the radiator than to force inself to pass through all those fins. Mine is made of fiber board in 3 pieces and I sprayed it black (it should be painted body colour) and it's been in place for 16 summers (89,000 miles) and it still looks good. At TRA in Ohio two weeks ago, I took 2nd in the judged concours with 89 points with all those miles since I finished the resoration in 1990.
https://www.britishcarforum.com/ubbthreads/photopost/showphoto.php/photo/1919/ppuser/4127
https://www.britishcarforum.com/ubbthreads/photopost/showphoto.php/photo/1919/ppuser/4127
Don, congrats on the award at TRA. It's nice to see a car that is driven recognized in concours competition.
On the TR4s you might find the shroud wider than the radiator. I fabricated pieces from fibreglass to fill in these aresa so all of the air is directed through the radiator. I find it interesting that a significant portion of the radiator is blocked by the lower valence; what were they thinking?
Bob
On the TR4s you might find the shroud wider than the radiator. I fabricated pieces from fibreglass to fill in these aresa so all of the air is directed through the radiator. I find it interesting that a significant portion of the radiator is blocked by the lower valence; what were they thinking?
Bob
gsalt57tr3
Jedi Warrior
Offline
My 57 TR3 had a wide mouth on it due to a collision sometime in past history. There was no radiator shroud. I had overheating problems with it, and put an electric fan on the front. Now that I have a small mouth, we will see how it works with the air channel and elecric fan. We are regularly over 100 in the California central valley during the summer.
I have a TR250 also and I would info on how to fit a radiator shroud. Years ago I bought what is shown to be the original fiber boards that mount to the side of the radiator but could never figure out how they attached to the body or radiator, for that matter. Last summer, I bought one for a TR4 and one for the TR6 hoping one of them would fit. But I can't find a way to make either of them work without some alterations. I'm thinking because we have a rare "hybrid", maybe that's the way it is and something will need to be custom fitted.
martx-5
Yoda
Offline
Moss Motors shows a different arrangement for the TR-250 then for the TR6. It is also different then the TR4. See parts 94 and 95 on the page I linked to.
Geo Hahn
Yoda
Offline
[ QUOTE ]
...I find it interesting that a significant portion of the radiator is blocked by the lower valence; what were they thinking?
[/ QUOTE ]
I guess that 30's technology (upright radiator) met 50's design (envelope body). I like the 'landscape' vs 'portrait' description.
Because where I drive sees 100+ temps much of the year I have fitted a plywood airdam to both TRs. Nearly invisible unless you get on the ground, but does throw air against the lower third of the radiator:
...I find it interesting that a significant portion of the radiator is blocked by the lower valence; what were they thinking?
[/ QUOTE ]
I guess that 30's technology (upright radiator) met 50's design (envelope body). I like the 'landscape' vs 'portrait' description.
Because where I drive sees 100+ temps much of the year I have fitted a plywood airdam to both TRs. Nearly invisible unless you get on the ground, but does throw air against the lower third of the radiator: