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Fuel Injection System on Craigslist

This may be the only time in my life I wish I had a TR6. Phew, OK that passed. Back to sanity. Just kidding. That set up is very cool. Hope it goes to a good home and doesn't sit on another shelf for many more years.
 
Bet it's gone by now. I'd buy it just to put it away to sell in about 10 years
 
Ya can't just bolt on that injection system and expect the 140+ HP that everyone seems to think will happen. There were several other things that the non-US engines had to get that HP, most notably the lumpy cam. I don't remember what else those engines had, but I'm pretty sure that the compression ratio was much higher also.
 
:iagree:
In fact, Kas Kastner claimed he could get more power from the ZS carbs than the Lucas PI.
 
They had a different cam and higher compression ratio, but I cant seem to find in my books just what the specs on those two differences are. I think the fuel pump was different as well, but I'm not sure on that offhand.
 
Didn't I just read here that they went back to that cam for the later 6's to help with that awful compression ratio they went to?
 
It would be nice if he had some better pictures showing all of the parts that he has instead of just 1 pic of a cardboard box with a bunch of parts. The way it is a buyer is just buying on faith that all of the parts for the PI system are there.
 
But it's a nice box
grin.gif
 
DNK said:
Didn't I just read here that they went back to that cam for the later 6's to help with that awful compression ratio they went to?
I believe it was a different cam altogether, used for later models with both PI and ZS. The PI models lost 15 or 20 hp, but apparently gained a good deal in driveability from the milder cam.

The PI used a relatively high pressure electric pump, not the low pressure mechanical.
 
DNK said:
But it's a nice box
grin.gif

Well, Yes it is a very nice cardboard box. I might bid just to get that box. :laugh:
 
I agree that it's short on pictures as the expensive bits are probably at the bottom of the box.

A thought in defense of the gentleman who posted the ad is that it's a classified ad posted to a specific region and not a worldwide auction. He probably figures that whoever buys this thing will be local and hands on. He probably also never imagined that a worldwide audience would be looking at this and critiquing his lack of pictures and lovely box.

Am I alone in being hugely, gigantically skeptical that a cam, compression and PI can take a 100hp TR6 to 150hp? Is it more than a little possible that the 150 number might be a wee bit exaggerated? (well, maybe not a wee bit). Weren't the hp numbers in the US required to be a measured number and the Brits were allowed to use a calculated hp figure? I just have a difficult time grasping that some relatively minor induction changes would result in a 50% increase in power.
 
Not sure the validity of the #'s but, anyone who has driven one says they are a kick in the pants
 
I believe it. The US spec TR6 actually made less power than the smaller TR4A engine, even though it had more displacement. And somewhere I've got a TR5 test report from an independant magazine that showed it was seriously quick (for the time and a measly 2.5 liters).

Never measured it, but cam, compression, exhaust header and a few other minor changes (smaller exhaust stems) made a huge difference in a (previous) TR3A motor. It was some serious competition for the Mustangs (until I started breaking driveline parts). And that was with the original carbs, intake, etc.
 
TR3driver said:
I believe it. The US spec TR6 actually made less power than the smaller TR4A engine, even though it had more displacement.

I haven't instrumented this but both the IRS and solid axle 4a - to be fair both have rebuilt engines at 87mm - feel noticeably quicker than my well broken in stock TR6.
 
I can see a 10, maybe 20hp difference, but 50hp? Cam/PI/compression? Really? The Moss supercharger kit adds 50 and I can buy that sort of increase from forced induction. It seems like there would need to be hours more prep put into a PI engine than a carbed car to get a 50hp improvement and I just don't see it from a non-crossflow engine.
 
joejoecat said:
I remember "back in the day" when the TR250 came out the TR4 & TR4A's were running around them.

Thanks to you and Tom Lynch for sharing.

Not wanting to cause a thread de-rail, but tell that to the armchair sports cars experts at the car shows. "Now, this is the [insert TR250 or TR6]. It is better than the [insert 2/3/4/4A] because it has a six cylinder engine..."

:wall:
 
cheseroo said:
It seems like there would need to be hours more prep put into a PI engine than a carbed car to get a 50hp improvement
OTOH, it might be fairly easy to take a 150 bhp engine and detune it to 100. Which is basically what happened. All of the initial development was done assuming that the PI could meet US emissions requirements. Then right at the end they had to hurry and cobble something together that would actually meet them. No money or time left for proper development.

After all, we're only talking 60 hp/liter. A 1970 Toyota Celica made 71.8 hp/liter with carbs (according to the first website I found)
 
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