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TR6 Differences in TR6 Body?

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crj7driver

Jedi Trainee
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I was looking at different pictures of TR6 engine bays and noticed a difference I was not aware of. On the image below is my dirty engine bay before my frame off. On the right side of the car (left side of picture) the indentation on the wheel well (for the air cleaner) only goes about half way forward. On a few other TR6's I have seen this indentation going all the way forward, have these Tr's been modified or were there variations. My TR is a 1970, just curious what years had which?

Thanks

DSCN1343.jpg
 
Here is a picture of a 73. The indentation goes all the way across.
Photo
 
I have a '71 and the indentation goes all the way across. Could it have been a design change to accomodate PI air intake manifold?
 
My early 71 CC58660 is all the way across. Lets find out when this started. How about the 70's and 69's???
 
They were designed to be PI cars from the start, even the TR250 which was a design modification of the TR5 specifically for the North American Market. I think it was a design change for/preparing for the change to the long runner intake manifold. But I could be wrong.
 
swift6 wins the prize. The larger, full length indent was indeed done to accommodate the longer (swept) intake manifold.

Ray
 
TR6oldtimer said:
swift6 wins the prize. The larger, full length indent was indeed done to accommodate the longer (swept) intake manifold.

Ray, so you are talking about the PI manifold? I was wondering if it was to accommodate the air cleaner for the carbs?
Click to expand...
 
Early TR6's and TR250's had a 'short runner' intake manifold. Were talking about the difference between the distance from the carb to the head when referring to long or short. Not longitudinally in-line with the engine.

Triumph went to a longer runner manifold to increase torque and horsepower while trying to counter the loss of power due to added emissions requirements and lower compression engines.

The implementation of the 'long runner' intake manifold coincides with the change to the dual outlet exhaust manifold and the differently spaced intake ports. Which is why the power output didn't change a whole lot when the compression dropped from 8.5:1 to 7.75:1. Lower compression but better breathing. The PI manifolds and airboxes fit just fine on the earlier, short indentation, inner wings. The extra room was needed because the 'long runner' manifold pushed the front carb closer to the inner wing when it pushed the carbs farther from the head.
 
Thanks,
Could not have said it better.

Ray
 
Interesting. My 71 had the short intake but the long indention.
 
You have to remember that 'just in time' inventory practices were a wet dream during TR6 production. The body panel change would need to preceed the manifold change otherwise there could be a stoppage in production if they tried fitting engines with long intake manifolds into cars without the right body fitting. Sort of a mass manufacturing version of a square peg in a round hole type of a problem. They probably needed to use up their supply of short manifolds before switching to the long ones as well to keep the accounting department happy.
 
DNK said:
What year did they go to the long manifold?
Click to expand...

The changeover year for long manifold, dual-down exhaust manifold, and lower compression was 1972. It wouldn't be too surprising if your car was built in the later half of 71 production that it would have the full length indentation.

This page in the Moss Catalog shows the different manifolds. The differences in 1969 to 1970-'71 (both are short intakes) and the 1972-'74 to 1975-'76 (both are long manifolds) are differences in emissions, vacuum and evaporative loss controls and fittings.
 
Mine was built in the 3rd qtr of 1970. One of the earlier 71's. a lot of 70's stuff
 
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