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TR6 BMW TR6 repower descision made.

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35thbdaytr6

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After lots of input from this forum, a couple hundred miles in my car as is, and lots of thinking about it, the decision has been made. For those of you who don't know, I have an early 74 TR6 with J-type overdrive. I have been considering repowering with a BMW M20 2.5l engine from an 87 325is, and started a post on this a few months ago. The engine is the same configuration, displacement, weight and size as the original, but has Motronic fuel injection, overhead cam and 172hp.
I have decided to get a Heritage Certificate, if the numbers on the car match, it's staying original. If it has a non original engine, it will most likely be converted.
I'm going to do a 4, 5, or 250 after this car is finished, I'll look for one that's locked up or missing it's engine and BMW power it instead. TR's may not ever be worth big money, but who thought Camaro's would sell for six figures?
 
I've always loved the BMW inline six. Such a smooth engine that is simply so much fun to rev to the redline. A great note at upper RPMs too!
 
If we were doing this for the investment we shouldn't be alowed to handle money /ubbthreads/images/graemlins/wink.gif I'm in it for the fun. These cars are an afordable way to have real excitment with a capable sports car.
Parts are inexpensive & a ton of performace stuff is available.
What ever project you finally do the end result should a fun car to drive not stare at & wax on sunny days 5 weekends a year.
Mitch
 
I glad you came to a decision. Me on the other hand, I am still up in the air. I am thinking of selling my 69 TR6 (CC25233LO, with a 1973(?) engine) and letting someone put it back to orginal. Then going out and finding another TR6 and modifying it just how I want with the BMW engine, wide tires and much more. What will happen, who knows, but if you do ever put a BMW engine in, I would like to hear about it.
 
Coop, it's not easy to modify a running car, is it? Even if it will be better, it just seems wrong. if the engine was toast, I'd swap it out without a second thought. I'm even reconsidering doing the body-off because it drives so good. Seems like the easiest way to spruce it up, check the frame for cracks and rebuild the suspension though.
 
Running, only if I push it /ubbthreads/images/graemlins/grin.gif. That's why it is a LONG term project.
This one needs a rebuild, new floor boards, still, battery tray, etc. But you have inspired me to go ahead and try to use a BMW engine. My goal on this one is to make it a modern sports car that I can run on the track. I want abut 200-250hp, the car to be lowered than stock, bigger tires & wheels (if need fenders flaired for those bigger tires & wheels), moditify the center dash to give me more room, set the peddles up so that I can heel-toe, and much more that is in my head. I have done 2 cars back to stock and now it's time to try something new.
 
I get a kick out of the spoon throttle, but the pedals are not set up for heel/toe. All of my other cars are set up perfectly, gas and brake close together, brake pedal gets firm right at the thottle pedal height. I reshaped the brake pedal arm on my old '76 Trans Am (455 4-speed) and it worked perfectly. I'll do it on this car also.
 
I´ve always loved the BMW engine sound and this was part of my project 7 yrs ago, when i first started my TR4A. i then bought a TR6 engine on ebay that was a total rip off and i finally found the original engine on my aunts back garden, half burried but luckily filled with oil. i finaly restored the original engine, but please let us know how you do, cause i sure do like the idea of a BMW on future triumph project.
 
"I have decided to get a Heritage Certificate, if the numbers on the car match, it's staying original. If it has a non original engine, it will most likely be converted."

To the best of my knowledge the engine and commission numbers never do match on Triumphs, the engine no. is always higher isn't it? I guess the Heritage certificate will tell you whether it's the original engine for the car.
In any case, the BMW repower sounds exciting although with all the suspension, brakes, drivetrain and wheel changes you will be making it should keep you working for a living to pay for it all, good luck on all your upcoming engineering decisions.
 
I know the numbers will not match each other, but the certificate will show if it's correct for the car. My engine number is lower than the commission, body number is in between, but close. As for the BMW parts, they are free, so it's more costly by far for me to keep the car stock.
 
If I'm correct, the commision number, engine number & body number are not ever matching numbers, They are always differant but should be within the model year range.
I think your knowledge of BMW engine & drive train would make an interesting project. The cost of making a TR go as fast as a BMW conversion would be excessive & not come close to the effertless power the BMW six would produce. If your up to the work I'm behind you . I do expect lots of pics so I can live vicariously through you. /ubbthreads/images/graemlins/yesnod.gif
Not being as electricaly informed as I would like, I guess the idea of an OBC & the electronics behind it scares me.
Most important the end result should be impressive to say the least. I'll probably see you in a future issue of BMW magazine.
 
Will the Overhead Cam fit under the TR6 hood, or will yoou have to put a scoop on? I think the BMW-6 is tipped to the right to clear the steering column, and you might just put side draft webers or FI with a custom intake manifold on. Squeezing in the exhaust could be a problem, though.
 
Measuring the engine on a stand, oil pan bottom to top of assembly shows it to be within 1/2 inch. Since the engine sits on an angle, it fits quite nicely. The M20 intake manifold does turn over the head, if this proves to be a clearance issue an aftermarket intake will eliminate it. Exhaust routing is fine, it's actually tighter than Triumphs.
 
[ QUOTE ]

To the best of my knowledge the engine and commission numbers never do match on Triumphs, the engine no. is always higher isn't it? I guess the Heritage certificate will tell you whether it's the original engine for the car.


[/ QUOTE ]

It would almost have to be. British Leyland sold motors to TVR for the Vixen 2500 & the 2500M, as well as used the 2.5L in the 2500TC and 2.5PI Sedans. Unless they skipped chassis numbers when they sold an engine off the TR6 line (unlikely) the Engine numbers would have to be higher.
 
I guess I'll know soon. My engine number is lower than both body shell and commission. I also have 72 style carbs. It's possible that engines were sent in lots to different places, with blocks of engine numbers all over. Depending on what order they pull engines out of the warehouse in, some could have been in descending order. The vehicle manufacturer factories I have visited inside (Chevy, Ford, BMW, Mercedes, Porsche) have engine and transmission assemblies on pallets 8 high taking up an entire section of the building. It sure would be a pain to always pull them in numerical order, rather than inputing a numer upon installation.
 
Well, the certificate came today, all numbers match. My engine is almost 1000 numbers away from the commission number, and yes, the engine is a lower number. Of course, something else happened, I sold the car and it's going to Finland! I might do a GT6 instead.
 
On my TR4 there is a 6,548 number gap between engine and commission, a 7,264 gap between body number and commission. Car is all original and BMIHT cert also shows those numbers.

I believe the car was somewhere for 6 months or so, then re-commissioned by the factory. Just goes to show how much these numbers can vary and still be original.
 
The sub-assemblies were running on seperate lines (often in seperate buildings) using thier own set of serial numbers, then they were assembled into complete cars and given the commission numbers. They would get out of sync for many reasons, like overlap models. I.E. TR250 (old body# sequence, new motor# sequence), and so on. So it's normal to have numbers that appear to be way off
 
I have been following this thread for a while. While I'm not a big fan of engine swaps, I like the sound of a BMW six in a TR-6. It seems "right" without being "overkill" . The concept reminds me of the popular engine swap in the UK that uses the Rover "K" motor in Spridgets....a nice "modernizing" without going bananas on power. (but no offence to any of you guys that are into V-8 swaps...it's your car and your business).

The BMW-engine / Brit-car swap even has a bit of historical presidence.
After WW II, some German technology was taken over by the Allies.
Most of us realize that the German rocket program (along with Werner Von Braun) was part of this.
But also as part of war reparations, the British took over the rights to the BWM six engine that was used in such cars as the pre-war 328. The sweet little German-designed, six-cylinder hemi engine was used in Bristols, Fraser-Nashs and AC-Bristols. In fact, this is the engine that Carrol Shelby removed from the little AC roadster when he installed the Ford V-8.

So the Triumph / BMW matchup reminds me of the old Bristol / BMW match.

As an aside, it's also interesting to note that the first BMW cars were British-designed and built under license (Austin 7s).

Anyway, G'luck whatever you do...sounds like fun!

By the way, here's a popular Triumph-oriented website in Finland that I enjoy reading:

https://personal.inet.fi/koti/jtabell/
 
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