The Triumph Dolomite Club - Discussion Forum

Searched on Wikiepedia and found this relating to the American market 900:

The 8-valve engines were phased out in 1989 and 1990, with the turbo versions having been removed in North American markets by the end of 1984; North American 900S models received the non-turbo 16-valve engine for 1986. A non-turbo 16-valve engine replaced the 8-valve FI unit in the 900i (900S in North America) as well, while the carbureted engines were dropped.


Therefore sorry Steve, seems I was asking a question about a car that never existed!




Ian.

sprint95m wrote:Searched on Wikiepedia and found this relating to the American market 900:

The 8-valve engines were phased out in 1989 and 1990, with the turbo versions having been removed in North American markets by the end of 1984; North American 900S models received the non-turbo 16-valve engine for 1986. A non-turbo 16-valve engine replaced the 8-valve FI unit in the 900i (900S in North America) as well, while the carbureted engines were dropped.


Therefore sorry Steve, seems I was asking a question about a car that never existed!

Ian.

Oh well! Every day a school day!

But it makes sense, carbs were getting rarer in the 80s, at least in Europe. The Saab 99 Turbo had a semi EFi (K Jetronic?) as early as 78. Why would they not also adopt it on the lesser models.
Yet my 84 Oldsmobile Custom Cruiser (think national lampoon's summer vacation) still had a 4 barrel carb to feed its 5ltr V8. This is one of the cars I was thinking of when I mentioned direct experience, It was fully smog proofed by GM and the result was a 5 ltr engine that produced only 160bhp and did 8 mpg on a good day! The poor thing barely had enough power to get out of it's own way!

Steve

Carledo wrote:...barely had enough power to get out of it's own way!

Classic!

That the Sprint 16-valve head wouldn't take the emissions control equipment is given here and there in stuff about the development of the SD2. There's somthing about the 8-valve heads having extra holes in the head for this that the sprint head didn't, and about how they abandoned the development work on an injected US version of the 16-valve head, in about 75, I think.

Graham

GrahamFountain wrote:That the Sprint 16-valve head wouldn't take the emissions control equipment is given here and there in stuff about the development of the SD2. There's something about the 8-valve heads having extra holes in the head for this that the sprint head didn't, and about how they abandoned the development work on an injected US version of the 16-valve head, in about 75, I think.

Graham

My Olds had holes in the head, into the exhaust ports, just upstream from the exhaust manifold and connected by metal pipework (eventually) to the air pump I mentioned. Other US market cars I have come across have similar equipment. This is probably what the holes are for. The 8v head has a much bigger gap here than the 16v one, maybe that's it!
The full reasons for abandoning work on injection for the Sprint motor will probably never be known, but I suspect it's a combination of difficulty with emissions and development costs (or royalties on a pre-existing system) Which is another shame, since I'm sure quite a few folk we know would LOVE an injected Sprint!
Saying that, I believe they COULD now get their wish (if their pockets are deep enough) since Jenveys, the Bridgnorth based and world renowned makers of bespoke injection throttle bodies, have now produced a throttle body that LOOKS like a 40DCOE Weber and fits onto manifolds designed for such. They aren't cheap though!

Steve

xvivalve wrote:I scrapped a (aftermarket) Sprint engined '7 a few years ago; it had most peculiar support structure for the engine, but one that looked to be original? From memory, a cranked cast bracket was bolted to one side of the subframe, passed under the upper part of the sump and supported the other side of the block!

The TR7 Sprint engine uses exactly the same engine mountings as a standard TR7. All TR7's have that peculiar kind of cradle under the engine that fits onto some of the sump bolts with a rubber mount onto the subframe and a cast bracket that bolts to the chassis rail on the carb side. Both rubber mounts are the standard TR7 square ones.

There was also a works competition sub-frame for the slant-4 engine that looks a bit like the TR8 sub-frame and does away with the fabricated mounting arm and casting on the carb side. There's a picture in the homologation papers, as I remember. I don't know how rare they are, but I had one some years ago. It got nicked from my dads shed.

Graham