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Triumph TR6 - Power increase
Any recommendations for the easiest way to get more power from a box standard TR6 engine with twin SU's?
Already have K&N's for a simple starter!
Can you recommend any cams, headwork, exhaust, flywheel lightening or so on? (Without spending thousands preferably).
"(Without spending thousands preferably)." UUUUUMMMM...nope.
Well maybe 2...toss the passenger seat and get rid of the spare tyre.......:)
|Hey James, Change std 78 series tire to 60 or 65 aspect ratio this will net 4 to 8% change in tire radius. Gives you more punch off the line but reduces fuel mileage and top speed. But the bulk of the ride is zero to 50mph anyway. The alternative is to spend unlimited amounts of $$$ and it still is not really fast but it will sound fast!!!|
|James, The easiest and cheapest way to get your TR to be a little more fun to drive is all in how best to get it to breath and a increase in compression, maybe to 10/1 This would necessitate having the head skimmed by about 080 thou, richer needles for the su's, and if the budget allows a good set of headers, Performance costs and I would not recomend any increase if the bottom end is in anyway suspect or low oil pressure. The biggest improvement you can make without any engine mods is a lighter flywheel. Good luck Clive|
|If David Johnston was involved with this thread,he'd say SUPERCHARGE IT!|
try a V8
|Let me offer up a caveat first, the text below is made operating on the assumption that you wish to maintain use of the Triumph engine in a normally aspirated form. If you are talking transplants or boost, it's a completely different game.|
While I agree with Clive that head work is where it's at, I have mixed feelings about the headers. Your car should have the later exhaust mainifold based upon the your other thread and it flows fairly well. Besides there is so little clearance between the frame and the where the headers would run, any collapse of am engine mount will put the header into the frame and you will find yourself with a cracked or broken header. He is spot on with the boat anchor, er, I mean flywheel. It is one heavy beast. Given the low end torque of the TR6, the loss in ease of launch due to less rotational mass will still leave the car easy to launch compared to most other manual transmission cars out there. Your engine will spin up quicker when there is less mass back there. And once again, he is correct in stating that if the bottom end is questionable, you must take care of it first.
Back to the head, in addition to bumping the compression ratio, get out the die grinder and your carbide bits and match those ports at both the head and the manifolds, then manifold to carbs, CC and match the combustion chambers and clean them up. If your SUs have the little poppet valves on the butterfly, take them out, remove the poppet, braze the hole closed, then grind and polish flush. Essentially we are saying trade your time for money to make some power.
Your cam (if stock) is the same as the late PI and carb cars, not as hot as the earlier PI cam, but definitely hotter than than the early carb cam. Changing cams also means new cam followers and possible valve spring changes, you are starting to spend money now. The trap to avoid in street cars is selecting a cam that makes good power in an RPM range that you will actually be using. There is no point in selecting a cam that get you an extra thirty horsepower if that power comes in so high that you will never use that RPM range. With the high piston speeds generated in a TR6, this is an easy trap to fall into so be careful out there.
The only person so far that has not spent your money is me....and I was just havin' some fun.
It appears the bottom line is...$$$$$$!
I am sure both Clive and SteveP will agree that once the head is off, just shaving it is only half the job. You may as well get the haircut too:)....valve job. So get the head done and change the fly wheel......$1,000?? With the head off, you will have time to do the port and polish....and the poppet thing-a-ma-jig.
If the car originally had PI, one of the easiest ways to get a big increase in power is to convert it back, complete PI parts appear quite regularly on Ebay.
|Well, there is no such thing as a free lunch. The same applies to power. If anyone is not willing to spend even a nominal amount, then talk of increased power is just that; so much talk and nothing more. If you look at my previous post, there is very little exchange of money involved. Headers, no, not worth the expense and hassle here. Change a cam out, there is much to consider and that runs into money, besides, there is not much to gain here vs the expense and hassle of the change out given the TR6 undersquare engine limitations.|
Basically the only real recommended exchange of money is tied in with the head shaving and the flywheel lightening operations. Once the set up is done, these are pretty much automated operations. The balance of the stuff is to be done by the user through trading of their time for the amount of money thay would have had to pay someone else to do that part of the work.
If we remove the cost limitations, then there are all manner of options that open up, roller rockers, proper cam change outs, different induction set ups, oversize valves, tapered guides, gas flowing the head, etc. The real key for what was asked is that it centers around the improving the flow effieciency of the cylinder head, with the flywheel thrown in as a sweetener. Based upon what our normal source charges us for work, those two things would in the $200USD or so range. You want him to do the rest of the head stuff? The price climbs much higher because of the amount of time involved in all of that hand working/touch labor.
|Ron. No US car had fuel injection so converting it back to Lucas fuel injection as a cost saving exersize would go against the grain somewhat! Nice thought though as when it worked as it was intended it was great|
I was assuming that James came from Bristol in the UK, therefore unless the car was an import it originally had PI. All UK cars had PI but there was a trend years ago to convert them to SUs as the PI was not well understood and gave problems but nowadays there are plenty of PI specialists in the UK that know their stuff so most people prefer the originality and performance of the PI. The parts for a PI conversion are easily and relatively cheaply obtainable over here as it was fitted to the 2500 PI saloon as well as the TR5 & 6.
|What about replacing the heavy, power consuming radiator fan with an electric fan. The fan assembly with adapter weighs about 10 lbs., which creates significant mass for the motor to rotate. An electric fan gets rid of that, is inexpensive and is better for the motor anyway. It may free up a bit of horsepower and will make the motor run cooler.|
|Ron. Sorry for assuming that was this side of the as there seems to be many over here! (in more ways than one!!!) I am going to have to explain that one over here. I agree with you that a Pi system when working correctly was great but much missunderstood, James. what side of the pond are you? Clive|
|Ron I have read my message and it has many words missing,I do not know If It is my computer or that BBS site does not recognize my UK slang|
|Clive Florida...UK slang .....don't compute.|
Clive its' gotta be a time difference from the meridian:)
|Rick I am English and living in FL for the past 4 years, is a term used for incorrect english,and spelling which I seem to do pretty well.|
|It did It again Slang is the word missing|
|Clive - aren't you just north of that triangle???|
James - I would stick with the SU's for the moment - they are easy to tune and give good mid-range torque. If it is a CP or CR and the engine is in reasonable nick then leave it alone. If it's a left-hooker coverted with no engine work done - you are up for some big bills and time off the road.
My recommendations for 'bolt-on' improvements are:
1 electronic ignition ((one hour job - fits in dizzy)
2 extractors first, exhaust when you can afford it.
Speak to Simon Young (MD) Phoenix Performance Exhausts Ltd
Unit D2-3 Kingsmill Industrial Estate
EX15 1BS(Road Map)
Tel: 01884 34777
Although no help with straight line speed - doing suspension work will get you around quicker
3 eurethane bushings everywhere
4 3/4" front anti sway bar
5 solid rack mouts to steering rack
6 telescopic rear shock conversion
Keep us informed as to how you go!
|Who can you recommend to do head work and flywheel lightening. Preferably somewhere based near Bristol?|
|Is that in Conn.|
This thread was discussed between 18/02/2005 and 19/03/2005
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