So, would a Saab B/H-series fit in a Triumph TR7?

[BattleRabbit]

Ok, so a little history for the un-initiated:

Way back in the 60s, Triumph decided to make a larger V8 powered sporty GT car than they ever had before. This car was known as the Triumph Stag, and it used a unique OHC V8 that never appeared in another car. When Saab caught wind of the V8 development however, they approached British-Leyland about a slant 4-cylinder OHC engine based on that architecture. This engine made its way into the early Saab 99s, and the Triumph TR7/Dolomite Sprint. On Triumph's side this engine fizzled out with Triumph, but Saab continued developing the basic Triumph block for years.

When I say years, I mean it. Saab's final development of that architecture went out of production with the 9-5. It went from 1.6l to 2.3l, gained eight more valves, direct ignition, turbo charging, and some of the first adaptive engine management software on a production car(Saab's Trionic). At the heart of all this though was a Slant four that Saab got from British Leyland in the mid 60s.

The Question:
Ok. If there is some commonality, then it should be possible to move some bits and pieces back and forth between the Saab B-series and the Triumph. What I'd be curious about in particular is an SPG powered TR7 or Dolomite. The Saabs used a distinctly different engine mounting system than Triumph did, but if the basic block is the same then this COULD be as easy as fabricating an oil pan for the bottom of the Saab engine(or maybe even using a Triumph pan), using some of the Triumph accessories and mounts(alternator and such), and mounting the whole shebang up to the Triumph transmission.

Just think:

200+ horsepower from one of the best sounding four cylinder engines ever


In an unloved wedge.

I think it'd be a hoot, if it would work. Anyone have any ideas?

[Dubai Vol]

There's a reason the TR-7 was unloved. Worst car I have ever driven, and I have driven some really bad cars.

[irsa76]

Only way to find out is try. BUT, the fact no one has actually done it tells me it either doesn't or it's not really a viable conversion.
I know it's been discussed among Triumph circles for many years, I started looking into it 10 years ago but can't remember what we found.

[BattleRabbit]

I actually did some digging, and there is a way to do it using a C900 block, a pre-94 9000 head/distributorless ignition system, a custom pan, and some NG900/9000 exhaust manifold and turbo parts. The transmission and everything should actually match up, which is neat.

I've always figured that the TR7 was panned for the same reason as the XJS; indifferent build quality. There seems to be a fairly healthy aftermarket for them however, and a lot of people swap a variety of V8s into them. Maybe then the aftermarket can solve most of their issues.

The long and the short of it is I already have too many toys, and this is more a curiosity thing than anything.

[2Turbos2Many]

Probably. A few friends put a 9000 turbo motor into an old jeep.

It wont drop right in.

[MCTB]

Talk to some of the web boards. The Wedge Shop, British V8, etc...


The TR7 is actually a very fun car to drive when it had power. The short wheelbase can catch up with you quickly though

[HarryHood]

Werent TR7's RWD? The 900's were FWD, and the engine was mounted backwards (belts next to firewall).

By all means, please do try to get a 900 engine in there, but it'll cost ya time, money and brain damage.

[BattleRabbit]

From my research using the engine out of a Pre-94 Saab 9000 Turbo is slightly simpler. They are distributorless(if you use the 900 engine the distributor is the biggest stumbling block to fitment), and the exhaust manifold will point straight down, rather than towards the front of the car. The block is 99% similar(save a distributor block off plate) to the 900.

On what would be the "back" of the engine in the TR7, everything to mount to the tranny is in the same place as it is on the TR7's original block on both the 9000 and 900 blocks.

It is theoretically possible. I found a build thread for such a car at about 2am while lying in bed reading on my phone last night. If I can dig it up again I'll repost it here.

Edit: I just found confirmation on Saab central that you can put any C900 transmission into any Saab 99, and apparently using the TR7 block with an early 99 head was a the hot ticket in the late 60s to making a 110hp Saab 99e. Stands to reason that the reverse would also work.

[Brendan@bwalkauto]

Having DD'ed a TR8 for awhile, I'd vote to find another continuation of an engine. The 3.5L V8 morphed into a 4.6L, and I always dreamed of that swap.

[BattleRabbit]

Having DD'ed a TR8 for awhile, I'd vote to find another continuation of an engine. The 3.5L V8 morphed into a 4.6L, and I always dreamed of that swap.

I'm a bit of a masochist, and I love Saabs.

[Troike]

Another Saab post from my brother-in-arms! (ex-98 golf owner here)

200+ horsepower from one of the best sounding four cylinder engines ever

If you like your car to sound like a piece of farm machinery ..
Actually, I haven't experienced the 16V (except for 1 ride in a 9000T, where I was more focused on the speed + heated seats)

Edit: I just found confirmation on Saab central that you can put any C900 transmission into any Saab 99,

I hear you need the Timing-chain cover (IIRC? I can check my book at home) from a 1980 (last year in US) 99 to fit the 900 5-speeds. Otherwise I believe they are a direct bolt-on (hopefully I'll find out at some point!)

good luck w/ the idea. my neighbor growing up built & raced Triumph Spitfires / TR7s (still does), though he kept the stock Brit motors I believe.

Obvious statement is obvious, but I am sure the 99 B-series (though harder to tune, acquire parts, etc) would be easier to work with than the H motor (1981+).
Everyone says the 16V H is difficult to swap into a 99, as it is much larger, and requires firewall modification. Having seen one, it is a very tight fit. I presume Triumphs have even smaller engine bays given their overall size, so an H might not even fit.

[turbo_nine]

At the heart of all this though was a Slant four that Saab got from British Leyland in the mid 60s.

Ricardo Engineering had something to do with the unlikely sourcing -- I think BL and SAAB were both using them for help. Saab's early four cylinder was rather heavily modified after the first year or two though, with only the pre-'72 engines wearing Stanpart logos.

[turbo_nine]

From my research using the engine out of a Pre-94 Saab 9000 Turbo is slightly simpler. They are distributorless(if you use the 900 engine the distributor is the biggest stumbling block to fitment), and the exhaust manifold will point straight down, rather than towards the front of the car. The block is 99% similar(save a distributor block off plate) to the 900.

Only if you get the 1990 9000 turbo 2.0 engine. Up through 1989, the US 9000 turbo had a mechanical distributor. After 1990, the 9000 turbo got a 2.3 block that is upright (and not shared with the classic 900, so not slanted at the base of the block).

So basically, the 1990 9000 turbo engine is the one to get, and they (along with the engine management and stuff) are unique to that year in the US and are not easy to find. My grandfather has one, though...