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TR6 69 TR6 pi rhd

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ichthos

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I have some questions about a 69 TR6 currently for sale I am hoping to get some information for. 1) Does anyone know if a pi rhd imported from GB can get registered/smogged in the U.S.? 2) Why did GB sell the U.S. version with carbs rather than just leaving the pi? 3) Anyone know what kind of gas mileage the pi gets compared to the carb version? Any help would greatly be appreciated.
Kevin
 
Right, the whole carb thing was to meet US emission requirements. The story I read said that Lucas had assured Triumph/Leyland that their PI system could meet US emission requirements, but final testing showed it was impossible to do so even with the relatively mild requirements in 1968. That led to an expensive crash development program that produced the TR250, which was widely criticized at the time for offering almost no performance improvement over the TR4A. After the emergency passed, I'm sure that management was loathe to try again with the same PI system and ever-tougher US emission requirements, so the US only ever got the carbed version of TR6. Years later, during the final few years of TR7/TR8 production, some US-spec cars did get Bosch electronic fuel injection, but only because by then they couldn't meet California requirements with carbs.

There's no way a PI version can pass a smog inspection, because the inspection includes the "type approval" from the manufacturer. I mean, it's more than just a tailpipe sniffer test, you have to start with a smog certified car and then the test is only to confirm that it is operating to original specifications. However, I believe that 69 is old enough that you may not have to pass a smog inspection to bring it into the country. I don't know what Washington state law says, though.

State of tune will play a huge role in either case, and parts to adjust the mixture profile are very scarce for either setup. But in a very general sense, they should be roughly comparable. The PI tends to run rich (which kills fuel mileage) but also has higher compression which tends to improve it. From what I've heard though, the PI unit is nearly impossible to successfully rebuild yourself, while the carbs are much, much easier. For my money, unless you really want the sachet of having PI, it makes more sense to start with a US-spec TR6 and add the cam, compression & exhaust to get the same performance as PI. Kas Kastner used to claim that he could actually get more power with the ZS carbs than with the Lucas PI.
 
I would run away very fast, if I were you. I have experience with triumph PI systems, and they are crap on a good day, and will require you modernizing the whole system to make it operate correctly in our climate. The petrol pump is a converted wiper motor and pron to over heating. The system is gravety fed initially, with out the benifet of a scavenge tank.
would opt for Webers, lightend flywheel, nice cam and rods.
 
If your looking for fuel mileage stay away from Webers. Only 18 mpg. With carbs and I get around 30 in the TR250 with the Zs. After completing the TR3 I have in process I have a 69 TR6 too and will stick with carbs. Was toying with fitting the original PI system too, but like Grantura I was told to run away from it. There is a modern version where you use the throttle body from the Zs and replace the piston inside the carb with a insert that has an injector in it. Then you use a ECU from a modern car to manage everything. At the TRF summer party 2 years ago I saw someone with a TR4 that had it and it ran beautifully. Even said on cold days he didn't need a choke. I getting ready to go to work so I can't look for the info but I sure there is someone on the forum that knows what I'm talking about. Also one of my customers rebuilds old Jags and he put them in the 6 cylinders cars. If I have time I'll stop and get some info.
 
Any car older than 25 years can be imported without meeting any of the regulatory requirements of the DOT or EPA. The customs people have been sticky with people using old data plates on newer things like Mini's and Land Rover Defenders. They have even been a bit ugly with Series Landy's with new frames.
 
My customer was not using the original system I saw years ago and was in the process of building one when I came in today. He is now using Pro EFI ECU and building everything else. This one and the Patton Machine is a lot more complicated then the one I saw at TRF. I'll try to look for my old info but not promising I'll find it.
 
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