Super Street Network

Due to the EU’s Global Data Protection Regulation, our website is currently unavailable to visitors from most European countries. We apologize for this inconvenience and encourage you to visit www.motortrend.com for the latest on new cars, car reviews and news, concept cars and auto show coverage, awards and much more.MOTORTREND.COM
 |   |   |  1973 Triumph TR6 - Project Car
Subscribe to the Free
Newsletter

1973 Triumph TR6 - Project Car

Part 4: A triumphant return

Rob Mullner
Jul 30, 2008
Epcp_0808_01_z+triumph_tr6+side_view Photo 1/2   |   1973 Triumph TR6 - Project Car

It's been a while since my 1973 Triumph TR6 graced the pages of this fine magazine. I'm pleased to report the time away has been well spent. Since the last installment (ec, April 2006), I've fixed most of the TR's perennial problems. And of course, added more power.

One of the more unsettling IRS TR traits is rear torque steer, which occurs at the most inopportune times. As the car is wound up, usually shifting from second to third, the tail will lurch to the right. The combination of stock trailing arm bushings and open differential amplified this behavior. Fortunately, the Moss Motors catalog is chock-full of solutions, so I ordered upgraded Prothane bushings and mated them to Goodparts adjustable trailing arm bushings, allowing a greater range of camber adjustment than the standard frame shims. The final piece of the rear-steer dilemma was solved with a Quaife ATB differential, which distributes the brunt of the torque to both halfshafts, rather than shunting it to one unsuspecting and unprepared trailing arm.

Epcp_0808_02_z+triumph_tr6_engine+top_view Photo 2/2   |   1973 Triumph TR6 - Project Car

With rear steer under control, I went on the quest for more power. As luck would have it, Moss Motors had been developing a bolt-on supercharger kit. My car was used as the R&D mule and, over the course of a year, it was taken apart, measured, poked, prodded and fine-tuned. With an additional 40 hp and 35 lb-ft of torque at the wheels, the car is a newfound joy. Since then, I've driven thousands of miles of California back roads, hooning to my heart's content. Supercharging fits the straight six perfectly, with a broad and instantly accessible powerband. The only downside to all this project progress is the pile of accumulated parts waiting to go on, including a fresh set of GTS Classics seats. Since I'm already having so much fun, I'm reluctant to take it apart any time soon, but keep an eye out for future upgrades and more in-depth information on the supercharger.

By Rob Mullner
4 Articles

BROWSE CARS BY MARKET

MORE HOW TO

In terms of project car building, some might assume that working for the Super Street Network and dealing with cars like this long-term 1992 Honda Civic VX hatchback means spending multiple days of the week wrenching away and making progress. The reality is, as much as I’d love to be able to do that, my
RodrezNov 16, 2020
Project K24's suspension gets an update courtesy of Fortune Auto, PCI and Circuit Hero
RodrezOct 22, 2020
We give you the quick rundown of how to troubleshoot suspected boost leaks.
Scott TsuneishiOct 22, 2020
For those who enjoy the audible, haptic feedback that comes from a snickety aftermarket shifter kit Hybrid Racing's Short Shifters offers the most diverse, innovative approach we've seen thus far from a bolt-in system.
RodrezOct 1, 2020
A step-by-step guide to knocking out parts powder coating projects in your home garage
Scott TsuneishiSep 17, 2020
Sponsored Links

SEARCH ARTICLES BY MAKE/MODEL

Search
CLOSE X
BUYER'S GUIDE
SEE THE ALL NEW
NEWS, REVIEWS & SPECS
TO TOP