LanEvo wrote:
Rebuilding the stock engine is definitely on the table.
When considering swaps, increased output wasn't really the goal. I was more interested in lightness and reliability, which is why I was looking at 100 hp 4-bangers from Suzuki and Mazda.
The stock TR6 engine does sound great. A stock rebuild might be the best choice.
Sorry to post twice in a row. You could still swap a BMW I6 in, consider the more plebian 6s from the 325 and 328. I think the most hp they made was around 180. The E36 engines are cheap, plentiful, and reliable aside from plastic cooling bits, which I am sure you would not use anyway.
LanEvo
Reader
8/30/17 1:16 a.m.
Joe Gearin wrote:
For a fun weekend car, keep the stock inline 6. Shave the head a bit, throw in a slightly hotter cam, rebuild the carbs and ignition system (Pertronix) and go.
On that subject, is it possible to justify converting to triple Webers for any reason other than it would be cool as E36 M3?
Ian F
MegaDork
8/30/17 4:53 a.m.
In reply to LanEvo:
You have an excess of time and tuning a set of triple Webers can fix that?
Personally, if I didn't go with EFI (Megasquirt), I'd probably go with triple Strombergs from GoodParts.
JoeTR6
HalfDork
8/30/17 6:25 a.m.
LanEvo wrote:
Joe Gearin wrote:
For a fun weekend car, keep the stock inline 6. Shave the head a bit, throw in a slightly hotter cam, rebuild the carbs and ignition system (Pertronix) and go.
On that subject, is it possible to justify converting to triple Webers for any reason other than it would be cool as E36 M3?
Putting Webers on a TR6 without other mods to take advantage of that extra (excessive) flow doesn't really make technical sense. The upsides are visual appeal and a wonderful intake howl. On the downside, you'll be increasing the number of tuning parts you need to buy/fiddle with and possibly washing down cylinder walls with unburnt fuel for little power gain. Now if you go with a hotter cam, tubular header, and compression bump with some head work, 150 hp is easily doable. Once properly tuned, they can be reliable carbs.
Has anyone figured out how to mate the 3-cyl ecoboost to a RWD trans? I think that would be fun in a LBC.
pres589
PowerDork
8/30/17 7:14 a.m.
Daewoo XK two liter inline six, pair of throttle body assemblies from Triump Street Triple, spend a year learning to TIG weld and make up a manifold from pieces of aluminum, no idea on the transmission and then you have that to build up. T-5 with a close ratio gearset would be my first guess but we're already deep into dream land.
2002maniac wrote:
Has anyone figured out how to mate the 3-cyl ecoboost to a RWD trans? I think that would be fun in a LBC.
If I recall correctly, it wasnt so much about mating to a trans, but as it was tuning a direct injected motor for anything approaching a reasonable expense.
Has that been solved yet? (ford racing didnt have an ECU set for the 3cyl)
The stock TR6 engine is a reliable unit. Maybe not up to modern Honda standards, but it's still a solid piece. The problems with these cars are usually from past owners hacking into the wiring system and messing things up. That and old wires / grounds going bad.
You can have a reliable and great sounding / driving TR6 without an engine swap. Honestly, it seems like more trouble than it's worth, unless you are planning on re-engineering the entire car. Warm up the engine a little as JoeTR6 was saying, with a hotter cam, shaved head for a bit more compression and make sure the carbs / ignition are in good order. Then call it done and enjoy the car.
I'd also agree with JoeTR6's advice on the triple weber set-up. It looks awesome and sounds cool, but doesn't really help performance unless you have a big cam, efficient exhaust and more compression--- and at that point, you are skirting the edge of making it less reliable. Sure does make an impression when you open the hood though!
Robbie
UberDork
8/30/17 10:27 a.m.
For a weekend-only car, I am actually a fan of just using period hot-rod techniques on the stock motor.
Bump the compression with a head shave, maybe do a hotter cam for more RPM (can you advance the stock cam?). Hand port all the passages in the head, as well as a good gasket matching for the manifolds. Maybe do a 3 or 5 angle valve job and some stiffer valve springs. I'd love to spend an afternoon on an old distributor machine, swapping mechanical advance springs until I found an advance curve I liked (of course, I would have to know what advance curve I WANTED, but whatever). Triple SU carbs all cleaned up and tuned up - watch John Twist's youtube videos on SU carbs - that man is a savant.
Then, grab a set of leather driving gloves, a scarf, and a pic-in-ic basket, and you're off.
Ian F
MegaDork
8/30/17 11:03 a.m.
In reply to LanEvo:
I just remembered where you live. Not sure what your budget is, but I'd probably just push the "easy button" and drop the engine off at GoodParts and let Richard rebuild it.
Depending on how nuts you want to get, you aren't far from Ratco either which can take care of that flimsy frame for you.
I've been driving and repairing a friends new-to-him TR6, and I think an engine swap would be pretty low on my list. I'd go for a chassis swap first, then a steering and brake swap, because all of those parts are at their limits handling the horsepower from the stock powertrain.
Don't take that as an insult to the car. I enjoy driving it, but are there ever a lot of vehicles out there that work a whole boatload better as a starting point for a fast car.
Robbie wrote:
For a weekend-only car, I am actually a fan of just using period hot-rod techniques on the stock motor.
Bump the compression with a head shave, maybe do a hotter cam for more RPM (can you advance the stock cam?). Hand port all the passages in the head, as well as a good gasket matching for the manifolds. Maybe do a 3 or 5 angle valve job and some stiffer valve springs. I'd love to spend an afternoon on an old distributor machine, swapping mechanical advance springs until I found an advance curve I liked (of course, I would have to know what advance curve I WANTED, but whatever). Triple SU carbs all cleaned up and tuned up - watch John Twist's youtube videos on SU carbs - that man is a savant.
Then, grab a set of leather driving gloves, a scarf, and a pic-in-ic basket, and you're off.
can you lighten and balance the crank/rods/pistons to allow for a longer powercurve/Higher redline?
Grizz
UberDork
8/30/17 1:38 p.m.
How heavy is the manual behind the 2.4 libertys?
150hp stock, apparently reliable and parts are friggen everywhere for them. I'd been holding that as a swap option on plenty of stuff floating in the back of my brain.
LanEvo
Reader
8/30/17 1:45 p.m.
From what I gather, the bottom end is probably OK and it's just the head that's a problem.
One solution might be to spend $800 on a rebuilt head from Roadster Shop and give them mine as a core. Seems like the quickest way to get the car on the road ASAP
Ian F
MegaDork
8/30/17 2:49 p.m.
In reply to LanEvo:
Or join the local Vintage Triumph Register chapter. I'd be shocked if somebody near by doesn't have a useable head among their pile of spares. Hell... I've only had a GT6 since 2011 and now have two spare engines...
In reply to mad_machine:
Yes, the rotating assembly can be balanced and a 6000 RPM redline is well within reach. Apparently, one issue is the harmonic balancer that seems to limit the useable rev range, but there is an ATI solution for that.
LanEvo
Reader
8/30/17 6:07 p.m.
I've already joined the NJ Triumph Association. The car comes with a complete spare head.
Here's a little more about the stock engine. We've done quite a few of these at Eclectic Motorworks and have dyno'd five or six of them. Stock, they make about 72-74WHP. Shave the head to bump the CR and add a cam and 100WHP is pretty easy. Port the head, add even more cam and compression, an exhaust, and a bit more carb and 150WHP is there. A supercharger will get you 130-150WHP with more torque.
Regarding carbs, the stock dual 1.75" ZS carbs will work fine even at the higher HP ratings because the engine doesn't rev really high. If you want more carb, the triple ZS setup from Good Parts is the easy button. I've tuned a lot of triple DCOE setups and I really feel they're just too much. You can't choke them down enough to idle as well they should and then you're just washing fuel down like JoeTR6 says. We've also just started playing with Mega/Microsquirt on British cars with the bolt-in 1.75" throttle bodies Borla is selling. Haven't tried a TR6 yet, but I think it would be a good option.
JoeTR6
HalfDork
8/31/17 7:03 a.m.
If you need a third ZS carb, let me know. I have a box of them.
pres589 wrote:
Daewoo XK two liter inline six, pair of throttle body assemblies from Triump Street Triple, spend a year learning to TIG weld and make up a manifold from pieces of aluminum, no idea on the transmission and then you have that to build up. T-5 with a close ratio gearset would be my first guess but we're already deep into dream land.
I've wondered how one of these engines would work in a Miata, kind of a modern Healey 3000. They're all aluminum, so shouldn't be terribly heavy. Because they were transversely mounted they should be fairly short, too. It's a pipe dream, but it would be cool to pop the hood at my local Miata club meeting and watch the reactions.
pres589
PowerDork
8/31/17 8:35 a.m.
In reply to DeadSkunk:
The Daewoo XK unit is crazy short, like 25 inches total engine length, and they're supposed to be quite light as you noted. I've never actually messed with one, they just sound interesting. Very fast web check says that the BP out of a Miata might actually be an inch longer overall but very large grain of salt with all that.
NA Miata with a five speed and a 2 liter Daewoo XK6 might actually lose weight, gain power, and probably gain mpg's in the process. Win win win! You get the lego's and I'll grab the bailing wire.