What modern inline engine would you put in a TR6?

[HealeyRick]

Here's a description of the BMW swap I found here: http://www.tr-register.co.uk/forums/index.php?/topic/7602-tr6-with-bmw-engine/:

"I am in the final wrap up stages of installing a 1995 BMW M3 S50 Engine and Trans in my TR6. Sorry to those that are offended but I have been restoring these Brits for years and decided it was time to build up a great street performer. Originally I had investigated the typical V8 conversions but was not impressed by the engine bay modifications required as well as the relocation of the steering shaft/rack. No matter how you engineer the fit of a V8, you're going to have to modify the steering shaft at the very least and incorporate a couple of extra joints. Most also have to move the steering rack slightly forward as well or cut into the firewall. Neither of these options was acceptable to me.

So, after several beers with a friend of mine who owns an independent BMW/Volvo repair shop, the old tape measure showed that the M3 engine would fit without any of these mods. Here what I had to do. First, accept the fact that you will have to do some wiring to accommodate the computer system. I chose the S50 M3 engine specifically because in the US, this was the only year that was produced with the OBDI software. The later models have a host of electronic and theft systems that would be a mother to deal with.

Here are the mods I had to do to accommodate. Believe it or not, the engine and trans slipped right in. The only sheetmetal work I had to do was concave left the inner fender well to match the right side to clearance for the intake manifold. It looks factory. I made some very simple engine mounts out of square bar that facilitated pancake style mounts typically used in the hot rod industry. The left bracket on the engine worked perfectly but I did fabricate a bracket for the right side of the engine. The transmission mount was a simple piece of angle iron welded in the proper location between the frame members bent to accommodate the BMW mounts. The steering shaft fit perfectly right down the side of the engine and cleared the intake manifold no problems. I removed the a/c and power steering pumps and had to play around with several different pulleys to get them to clear. I think they ended up being Volvo for the water pump and early 3-series for the crank. I used an alternator off a Suzuki Samurai, which was the smallest I could find, and it still puts out 55 amps. This alternator does require an idiot light to excite. The radiator I chose was a BMW e36 as well. I installed some simple rubber buffers on the lower frame skid plate to locate the bottom and fabricated a new radiator duct out of aluminum that located and fastened the top. Oh, and I did fabricate a new front cross member between the spring towers up front. The factory one might have worked but the clearance was just too tight with the pulleys I chose. The lower frame cross member was chopped into about 1/2 of its thickness but severely beefed up. This was to clear the oil pan.

The cool thing about this install is that if you didn't know any better, you'd think BMW designed this engine for the TR6. It is an absolutely beautiful fit. I did convert the rear diff to an Infiniti Q45 LSD / 3:54 which will work great with the transmission. Also had a company ( www.cvaxles.com Kevin) make up some rear axle shafts with CV Joints that will better handle the power. The drive shaft was a combo of the BMW with the Infiniti/Nissan rear flange. An actual drive shaft company did this.

Currently, the chassis is awaiting the tub, which is being finished up at the body shop as we speak. It fits perfectly and all is hooked up and plumbed. You will need to fit an electric fuel pump and I would also suggest strengthening the frame. I have added a lot of steel to the frame, reinforced all the week areas and will install a roll cage to further stiffen it up.

Hope this helps. At least on idiot over here in the US is doing what you are asking about.

Dave "

[alana]

That's Dave Dewalts car.
Google milemarker60 and you should find pictures.
It was for sale about 9 months ago for 40k. Fell through because (ostensibly) the purchaser didn't fit.

[MGBV8]

milemarker60

I had always wanted to build a "fast" British car and wanted to craft something unique. My intentions were to build a virtually stock appearing TR6 that performed at insane levels while delivering exceptional reliability. Various V8's have found there way into these cars over the years but require many modifications that I was not willing to live with (steering geometry, firewall cutting, weight changes, etc.). While this was no mere "bolt-in" process, the net results lightened and balanced the overall car and required absolutely no changes to the steering and suspension system. It was almost as if BMW had this engine bay in mind when they designed their S50 M3 Power Plant. Engine Mods were held to Head-Work, 8.5lb Aluminum Flywheel, HD Clutch, Cold Air Intake and a custom Chip by Jim Conforti taking into account this particular application with the installed exhaust, no Cats, Intake, Oxy Sensor, Flywheel, Curb Weight and 7000 RPM Limiter. It's absolutely ridiculous how fast this thing is.

I stripped the entire TR6 down to a pile of nuts and bolts and shipped off the tub and panels to be Soda Blasted before taking them to the body shop. This gave me the opportunity to tackle the frame and drive line. I started by having the frame sand blasted then welded in a lot of additional steel at all the known and unknown weak spots including the TSI Rear Strengthening Kit and ¼" plate added atop the rear spring mounts. Every factory weld was ground and re-welded to insure zero issues with frame cracking, twist or degradation due to the added HP and suspension modifications. I also had a local race car fabricator custom make a 6-point roll cage that ties into the frame directly via the four body mounts in the cockpit and thru the rear bulkhead and down to the aft frame sections (clears the roof). This is probably the most torsionally stable Triumph Frame you'll ever find and the driving changes it made are very obvious. Next I coated the frame with POR15 along with all the suspension bits as it holds up much better to rock/road debris than Powder Coating. I utilized all of Richard Good's suspension upgrades which include Lowered Springs, Sway Bars and Adjustable Trailing Arm Brackets. Due to my prior experience with Koni, I selected Spax Adjustable Shocks all the way around which once set-up match the over-all handling perfectly. I must admit, I had Roger Hurst (local Triumph Racing Legend) actually "set up" the suspension once loaded to insure the proper geometry required to provide the best handling and ride. I also added a new quick ratio steering rack combined with Richard Good's Aluminum Rack Mounts and a slightly smaller diameter Leather Moto-Lita Steering Wheel. I'm in the aviation business and have access to all sorts of great hardware so all the suspension and brake nuts and bolts were replaced with AN series or Grade 8 at a minimum

I changed out the front brakes to Toyota 4-Runner four piston calipers mated to Toyota Cressida vented rotors which as many of you know is a very simple conversion. For the rear I ran across a couple of guys who campaign a full-race TR6 that designed and machined a race-approved disc brake conversion kit to install Wilwood Aluminum Calipers clamping on 280 ZX Rotors. They were in process of commissioning a machine shop to make a few more sets for a new car they were building and were nice enough to have a set made up for me at the same time while sharing their engineering. This is not one of these cheap kits that come around every so often but a serious chunk of machined aluminum that has been approved for use on the track. I also had Classic Tube make a complete set of Stainless Brake lines and sent out the booster for o/h and replaced the master cylinder and filled it all w/ DOT5 fluid. I installed a Wilwood lever-style brake bias adjuster which can be manipulated on the fly by the driver if you want to change the proportion of force front to rear. I have installed a B&M Launch Control Kit (line lock) in the front circuit but I did not wire it up. It's just one more thing to get me into trouble either by shredding too many tires or by the local law enforcement. It's fully plumbed and the wires terminated under the dash, just need to hook up the button. The hardware combined with the Bobcat pads make this 6 stop on a dime with no wheel lock-up and much reduced fade.

The rear differential is an obvious weak spot along with the rear axles on TR6's especially when horse power is added. I opted for the Nissan/Infiniti R200 dif as it was extremely easy to adapt to the frame, provided unquestionable strength (the dif of choice in the drifting crowd), super LSD performance and available in a ratio (3.54) between those used by the stock M3 and the full-race M3. I commissioned Kevin at Constant Velocity of Ocalla (FL) to design a set of rear axles utilizing CV-Joints and able to take the added stress of HP I was going to throw at them. As with everything on this car, they weren't cheap but with out question one of the most required parts to change out which many Mod'ers forgo when hopping up a TR6.

I had the entire interior, fender wells, trunk area and bottom of the tub shot by the local Rhino Liner shop after blasting and priming. This stuff totally encapsulates all the known rust areas for future protection and offered an indescribable reduction in noise and heat and increase in solidity. For the body, I chose a BMW M3 color, Imolla Red II which is a beautiful deep and slightly dark red. My body guy sprayed all components and panels separately with a PPG system utilizing Base and Clear Coats. The body is completely assembled with Stainless Steel Fasteners to alleviate any future corrosion and they simply look nice and actual DumDum was sourced in the UK to seal the seams between the fenders/wings and tub. I shaved off the front side markers on the fenders and door locks to clean it up a little but left the original front turn signals under the grill to accommodate state laws. New front and rear light assemblies were installed too. I have two new Bullet Mirrors for the doors which I have not installed as I preferred the look and they are not required in the State of KS. The hood / bonnet cable has been removed in favor of a direct release rod courtesy of Macy's Garage so no worries about stuck hoods because of broken cables. No other body mods were made as I truly wanted to keep it in stock form to any on-looker.

One of the weakest points to any British car is the original electrics and wiring. I contacted Dan Masters of Advance Auto Wire who makes an over-the-top 21st century designed wiring kit for several makes of Brits and had him make me a custom harness for my project. The heart of the system is a power block that utilizes individual fuses for all circuits and relays for all heavy load items just as on current vehicles. It probably added 25bls to the car in copper as the wire gauge was quite oversized compared to the original but well worth the trade off. All the instruments were switched to electric models from AutoMeter and incorporated with the harness. I also replaced all indicator bulbs with high output LEDs. Once I completely ran the new wiring, I removed it before termination and "snake-skinned" the entire thing. Most would have just zip-tied it all but I really can't handle the mess associated with typical aftermarket harnesses so it truly looks stock. I have wired in a CD/Stereo unit but haven't felt the need to cut in speakers as the note of the exhaust is all the music I need. The Optima battery has been relocated to the right rear trunk area mounted in a custom keeper and a main battery cut-off switch is mounted on the firewall with the kill-key extending into the glove box for easy access. Both the fuse block and BMW computer are mounted inside the passenger foot well safe from any contact with exterior water or hazards and out of sight.

The interior is outfitted with Miata Seats that do have speakers in the headrests and seat heaters to keep your buns warm. They are trimmed in Tan Leather along with all the other interior panels which are piped in a contrasting brown (no Naugats were skinned or harmed as I went the cow skin route rather than Naugahyde). The carpet is tan wool from Heritage and has been installed in a fashion that the floor pieces can be removed on the instance they get wet. The window regulators, channels and seals were all replaced with new units that, believe it or not, don't rattle. New seat belts were installed as well as a set of racing harnesses for track days. I never particularly liked the TR6 top mechanism as it just sits like a lump behind the seats and detracts from the clean lines of the car. I took this opportunity to modify the bows from an early TR4 as a replacement as it affords for the complete removal of the soft top for stowage in the trunk and the bows tuck out of sight behind an interior panel. The windshield frames between the two cars are the same but I did change the top finisher to the TR4 as its soft top fastens at the front to a lip under this. I never had the intention of purposely driving the car in foul weather but did feel it important to have an emergency plan just in case I got caught out in the rain. I contacted Randy Keller of Prestige Auto Wood to craft me a custom dash laid out in the stock form but for use with the AutoMeter instruments and LED indicators. I chose Hawaiian Koa Wood for this and he also matched a panel for the switch plinth. The visors, mirrors, crash pads, windshield trim, etc. are all replaced with new. An insulated poly transmission tunnel has also been added to replace the original cardboard unit. Back in the trunk, I replaced the original fuel tank with a 16 gallon custom made aluminum unit that resides in the spare tire well.

The 17x8 3-piece wheels are BMW Style 5 Composites made by BBS and are found on 5-Series Sport Models; always my favorite style of all time and they look perfect on my TR6. I was not willing to settle for any type of adapter plate to mount them and as luck worked out, the offsets were perfect. I sent them out to a shop in CA who specializes in wheel customization and they disassembled them, filled and re-drilled the centers for the TR6 bolt pattern, sent the centers out for powder coat and polished the rims. I was able to remove the BMW emblems from the center caps and with a little modification install the TR6 chrome emblems with red stickers in their place. They absolutely look factory. I wrapped them with 225/45/17 Falken Azenis RT-615 tires which are a new class of DOT and SCCA Spec race approved tires. They are a little more suitable for daily driving than the typical "R" compound tire while providing exceptional grip.

Pretty stupid as I refelct...Guess we all need a hobby.

Dave DeWalt

[MGBV8]

Awesome M3 Tr6. Shame he didn't send Curtis a HIWD.  Looks like the Photobucket pics have been taken down. Grab the ones on Google while ya can.

Found more pics. Bottom of page. Click for larger pics.

http://www.davintosh.com/2011/08/30/bmwotd-triumph-tr6-bmw-m3-driveline/

[69 TR6]

Hi BWA,

This is just what I am looking for as I have a completted TR6 and don't want to start hacking it up, however I do want my car to have more power and drivability to it.  Did you have much trouble with the electrical?  I was so afraid of the old wire I had a guy install the Dan Masters kit (nice stuff).  You said you needed to move steering, did you need to add joints and attach it to the frame like the V8 guys are doing?  Is this an affordable option? Why did you need to get a kit for trans? Are their any 3500's with rear wheel drive set ups?

Looks great,

Dennis

[Phil Crawford]

Ed
Have you considered one of the nissan skyline engine transmission combinations.  They are JDM inline 6 turbo charged and horsepower is almost unlimited.  They are very light and I considered one before I used a V8. If I wasn't in such a rural area I would have used one of the later models. Most in stock form are about 300+ hp.  Food for thought.
Phil

[v869tr6]

Well I pulled the trigger and went with a low mile Nissan RB25 non-turbo. I don't know how long it will take to get up and running but the thought is I shouldn't need to mod the whole car for 200 HP but it should make for a very nice driver. I do know it was a blast at BIR up until the rod bearing started  to go bad in the stock engine. A 200 HP hi winding 5 speed TR6 should be cool. Thanks for all the input.
Hope I don't need to move the rack to far.

[88v8]

If you move the steering rack, be careful that you don't create bump-steer.
The length between the inner ball joints is critical, so the wrong rack can cause bumpsteer. As regards rack position you should be able to draw a straight line from the centre of the top wishbone inner pivot to the same on the bottom wishbone, and the line should pass through the centre of the inner joint on the rack. Obviously raising or lowering the rack on its mounts, just a small amount, will make a vast difference to the bumpsteer.

Here's an article on the subject.

http://www.tsoaq.org.au/technical-information/22-steering-racks.html

Ivor

[v869tr6]

Ivor
Thanks for the post, that may help a bunch of people that are moding these cars. I can't really picture where to draw the line thru the piviots in my head, but having lowered my car and reading the info it looks like I will need to move the rack to the rear and raise it up.
Cutting into the firewall to move the engine back a couple of inches won't be that bad, but I believe the shifter will already be about 4" or 5" back from the stock location. Looking around on the net it looks like there are a number of companies that make balancers for the RB25 so if I need to shorten up the engine I can get a custom balancer made. The stock balancer has 3 different pulley grooves and I should only need the one position closest the engine. Can't wait to get the engine and do some real measuring.

[ALV]

I hope you are going to post pictures of the build. I considered a Nissan SR20DET (S13 Black Top). Its is  a 4 cylinder making about 205 horsepower stock. I thought with 2 less cylinders moving the engine to get a close to stock shifter position would be easier.

[Oldsie]

I've chosen a 2008 Ecotec LE5 2.4L and 5LE40 Auto Trans (standard Solstice package) into my TR4A.  Stock ECM tuned to remove VATS, emissions, etc.  Steering reroute around stock intake manifold required 3 universals, but angles are small.  Minor sheet metal surgery around alternator, drivers side,  around stock exhaust manifold, passenger side, and near rear right side of engine to clear stock heater hose nipples.  Minor.  No firewall mods.  Stock battery location.  Custom engine mounting hat sections welded to frame, using stock GM engine mount brackets.  Auto trans chosen because stock Solstice manual shift point is very far aft, would interfere with hand brake.  Also, this allows use of paddle shifters if desired.  Stock Transmission Control Module, but aftermarket ones available.  Difficult to match 5L40E output flange to anything "standard", but it's done...  Custom trans rear mounting cross-member with stock GM aluminum/rubber mounts.  Homemade fiberglass transmission cover.  Not yet running, but if stock ECM shows a problem, it appears that MegaSquirt has a good solution including VVT control.  170+ HP stock, haven't looked into turbo yet.

[rficalora]

Bill's gonna be dancing a jig!

[pointnette]

What about Bill Young's MGA AMC 4.0 L6 experiment?
http://forum.britishv8.org/read.php?13,6370
From what I've read, hot rodders love 'em. They're said to have gobs of low-end torque and can be built to deliver lots more. Also, they're reputed to be good for 300,000 miles. The problem is, if memory serves me correctly, they're about as heavy as the Austin engine in the Big Healey.

Stan

[DoctorEurocar]

BMW M30 3.4 Litre inline 6 cylinder single overhead cam, Bosch 059 ecu single T66 turbo looking at easy 400rwhp.. I have done this before, But I started out with the better 3.4l Factory turbo block as found in a european spec 1985 BMW 745i Turbo if could find that block good for 550 rwhp on all stock internals with exception of rocker arms.....

I considered this engine for my Stag project but its just too heavy. I am not sure on the factory TR6 inline 6 weight but they may be close..

The Electronics are simple to allow this conversion, you can get the ultra strong BMW Getrag 260 or 265 5 speed manual the 265 being able to use a cable for speedo where as the 260 has no provison for a cable..

My other non british project in a 1995 Mercedes E320 Cabriolet custom turbo that is being repowered with a BMW M30 inline 6 cylinder and single turbo..

Good luck either way sounds fun

[Trick6]

I have installed a 06 Cobalt (Ecotec) 2.0L LSJ (supercharged) engine.  It is a great performance package. It dyno'ed 218 RWHP.  I put a GM (world class) T-5, a 4.08 R200, and Goodparts CV Hub/Axle upgrade behind it.   The weight/HP/ ratio, about 10:1, is a balanced relationship and the car is not overpowered, if there is such a thing.  I get 29.5 MPG highway; the 5 th gear at 0.63. I now have a very happy and very fast roadster.

[Trick6]

Here are a couple of photos of my TR6 with the 06 Cobalt LSJ.

This was taken just before the hood was installed.  the air intake filter is up front a side the radiator enclosed by the Goodparts shroud.

The drive-by-wire throttle body was at the end of the supercharger hitting the brake booster so we cut it off and moved it to the old battery area via a 90 degree tube.  The ECM is against the firewall there also.

It all fits under the hood nicely and is so much fun to drive.  It's a real sleeper.

[Moderator]

VERY nice! Would love to see detailed photos/write-up for our Gallery section.

[Michael Hervey]

Can anyone provide any input on the GM 4.2 liter inline 6 cylinder motors? They are 270 hp stock, all aluminum, and pull-outs are in the $600 range on eBay. They came in Trailblazers and other vehicles, so there are a lot of them around. Supposedly adapters exist to mate up a T5 transmission.

 Sounds like a winner to me, except they are 30" tall.  Will it fit with a stock hood?

[BWA]

I do not think that a 30" tall inline 6 would fit under a TR6 hood.  A way to check is measure the height of the existing TR6 engine.  
The GM 3400 V6 I put in my TR6 is about 28" tall at the tallest point and I have about .5" clearance above it.
That engine you are looking at might fit if you remove the battery tray and shove the engine far back as possible.  Doing this would entail a lot of cutting and rejigging the fire wall/transmission tunnel.

Cheers
Byron

[Michael Hervey]

Thank you Byron-

[stratocali]

I have a TR250 and was also wondering about transplanting an M3 engine.  The E46 S54 develops around 330 hp which is plenty for me.  Looking to avoid major cutting associated with the V8 transplants.  Does anyone have dimensions or more info about the feasibility of doing this?

[BWA]

Larry send an e-mail to Dennis Matthews,  his moniker is 69 TR6.  Dennis is putting a BMW straight six in his 69 TR6  and he might be able to help you on engine dimensions.  

Cheers
Byron

[DiDueColpi]

Just a quick little tip that I use all the time.
Take all of your measurements for the new engine off of the crank centerline.
If the original engine is still in your car then base your conversion on it's crank position.
If not, lay out a straightline from the front of the car to the diffy and base your measurements on that.
Make a couple of quick cardboard engine templates based on the new engine measurements and away you go.
I've even made up a full cardboard engine and trans a few times when things got pretty tight.

Live like you mean it.
Fred

[ainadude]

Second the suggestion by doctoreurocar about the BMW M30 engine. These used to be VERY common in junkyards, as they were installed in everything but the 3 series cars for 15-20 years. Probably lost a lot of potential donors in the wake of the Cash for Clunkers debacle here in the U.S., but these engines should still be pretty easy to find in good nick. Well cared for, they're bulletproof, simple to maintain (timing chain instead of timing belt) and turbo kits are available (even from the factory, but of course those are pretty rare on our side of the pond), plus the ECU is very simple and should represent no impediment to installation and proper setup. Think they put out a little over 200hp in stock form and the internals can handle quite a bit more if required. Only downside I can see is it's probably easier to find one mated to an automatic rather than a five-speed transmission. Bonus: one of these would look quite period correct under the long hood of a TR6 (lots of simple cast aluminum atop the engine).

The later, twin-cam M50 engine found in '90s-era 3 and 5 series cars is also common -- I think someone else suggested this, as well. Widely available, these motors are smooth and powerful, uber-solid and fairly compact. And I think turbo/supercharger setups are widely available. However, I believe at least some of these are OBD-II, so installation may be a bit more complicated. On the upside, tons of these can be found with very robust 5-speeds. Same goes for the S50/S52 motors found in M3s of the period -- more expensive but still fairly common.

Holy grail from Munich would be the hallowed S38, an absolutely brilliant twin-cam engine that was installed in E28 and e34 M5s and E24 M6s. As I recall, it's an update of the engine BMW installed in the fabled M1, which I think used a tweaked M30 block. Quite rare at this point and very expensive (five-figure rebuilds are the norm), but great power (256-286hp, IIRC) and the valve cover, intake manifold and bellows combo is nothing less than automotive engineering porn. Only available with a 5-speed (Getrag, I think). Not sure how amenable these are to a turbo or supercharger installation (and personally I wouldn't want to mess with that lovely intake setup), but If money were no object, this is what I'd want to put under the hood.

Hope these offer some food for thought ... and best of luck.

[MustangSix]

This is an old thread, but let me toss out one more possibility - The 4.0 Jeep.

Been around forever so they are avaialble and inexpensive.  Rear sump, so it packages easily.  Roughly 18" from crank centerline to top of valve cover and about 32" from bell face to front of harmonic damper.  ~450lbs with iron head.  

Stock it will make 170 to 190 hp depending on year.  Edelbrock just released an alloy head that will allow you to make power well in excess of that and shed over 40lbs to boot.  200+ hp would be easy.  http://www.edelbrock.com/automotive/mc/cylinder-heads/jeep.shtml

Any V8 or six cylinder Jeep bell will fit allowing you to bolt on a T-5, AX-15 or Toyota trans, or any number of other common manual transmissions.

Several exhaust header possibilties, but the stock dual exhaust headers or manifolds work well.

On the intake side, all 4.0 engines had an ugly looking EFI but with a little imagination something better looking could be built.  Same port layout as the Datsun 240Z - maybe the dual SU intake from the Datsun could be adapted?

Stroker kits are available - I think you can build these to 5.0 liters.  Lots of cams available.