TVR 2500 engine changes

TVR 2500 engine changes

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Discussion

Artracing

Original Poster:

43 posts

62 months

Tuesday 21st June 2022
quotequote all
I’m restoring 74 TVR 2500M . Body off.
Keeping it mostly original but want to update the TR6 engine, not replace it. I’ll put V8 in the second one I have.
Not crazy about points or mechanical fuel pump. Headers?
Keeping Stromberg Carb.
How much vacuum hardware do we need?
What have you done to yours ?

Rob


Grantura MKI

817 posts

165 months

Tuesday 21st June 2022
quotequote all
Flow the head, nice pistons, alloy flywheel, triple Weber’s just start.

Artracing

Original Poster:

43 posts

62 months

Tuesday 21st June 2022
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Lol, I was looking for something more conservative this is a driver. Thanks

Grantura MKI

817 posts

165 months

Tuesday 21st June 2022
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Have done this set up on a road car with out any issues, except it was quicker than a V8 car.

GAjon

3,804 posts

220 months

Wednesday 22nd June 2022
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Grantura MKI said:
Have done this set up on a road car with out any issues, except it was quicker than a V8 car.
And they also sound fantastic.

Mercdriver

2,632 posts

40 months

Wednesday 22nd June 2022
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Are you sure it has a TR6 engine and not the American spec TR250?

I had a 2500M in the 90’s with American spec engine. P1$$ poor performance!

Look at a TR6 head, near the front of the head is a web in the casting and compare it to your head. The difference if I remember is about a mm. either bin your head and get a TR6 head or have a machine shop remove material from the head to make it a TR6 one.

I did the above, fast road cam and twin SU’s, electronic ignition garage reckoned it was good for 170bhp at flywheel.

Are there no triumph specialists where you are?


Edited by Mercdriver on Wednesday 22 June 10:37

Artracing

Original Poster:

43 posts

62 months

Wednesday 22nd June 2022
quotequote all
I have only just gotten into this. No research. I’ll check it out and see.
Thanks for heads up.
I’m keeping the car stock.

Moto

1,261 posts

260 months

Wednesday 22nd June 2022
quotequote all
As a daily driver just change the points / condensor out for a cheapo electronic unit such as the Accuspark and get the engine setup on a RR. You should get reasonable road performance and take away the constant running issues of unreliable ignition etc. £300 well spent.

If you want more performance out of the Triumph 2500 engine then it's a case of how much do you want to spend? It's a bottomless pit where even basic fast road mods (Carbs & cam etc) will likely cost £000's. Not much point if you're planning a V8 install.

Personally I'd invest in the 2500 lump - well done it's a really nice engine, if a touch heavy. Sorry I'm not a fan of V8's in an M. If I wanted to go non-original with bags of performance and suitable for both road & track use, I'd go Duratec or something similar.

Moto

Artracing

Original Poster:

43 posts

62 months

Wednesday 22nd June 2022
quotequote all
Thanks. Ignition will be replaced with electronic. Not sure about the digital distributor for stock engine.
I never seen so many vacuum lines and hardware. Would be nice to minimize them.

Rob

GJL

249 posts

258 months

Saturday 25th June 2022
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I'm running 123 Ignition in my 71 Vixen 2500 and I am happy with the results. Removes the points and condenser niggles and you can just pop the old distributor back in if you need to return to original or you can keep as a spare in the car if you don't trust modern tech!
I went for the bluetooth version so you can tweak advance and retard curves and store a number of different curves to swap and change and you can tune the car on the spot via your phone. It has a rev limiter option and you can immobilise your car and just use a PIN on your phone to disable.
Some will be derisory of it but my personal experience has been very favourable.

Artracing

Original Poster:

43 posts

62 months

Saturday 25th June 2022
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Good to hear about 123.
I will plan that.

GJL

249 posts

258 months

Saturday 25th June 2022
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Looks like it will be a while before you need it! biggrin

Artracing

Original Poster:

43 posts

62 months

Saturday 25th June 2022
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Yea, few weeks. Lol

Slow M

2,787 posts

213 months

Saturday 25th June 2022
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Grantura MKI said:
Flow the head, nice pistons, alloy flywheel, triple Weber’s just start.
^What he said, plus bigger valves with undercut stems, decent springs, and a hot cam. On the exhaust side, a proper header and muffler system.

Too many people are afraid of going big with the cam. Don’t forget how light these cars are, and how I6 don’t get as rough with performance mods as I4s or V8s.

Artracing

Original Poster:

43 posts

62 months

Saturday 25th June 2022
quotequote all
This one is getting a very mild cam and balance crank, new piston. Maybe headers.
Sunday driver.

I’ll come back to you guys when I put a 302 V8 in my second TVR.

Rob

GTRene

17,776 posts

231 months

Saturday 25th June 2022
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Artracing said:
I’ll come back to you guys when I put a 302 V8 in my second TVR.

Rob
now you are talking bow
but for now, respect for all the work ahead of you.

LLantrisant

1,002 posts

166 months

Sunday 26th June 2022
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if you dont care about originality and therefore maybe loss of value...go for a v8.
if you want to keep the (rover) V8 in a classic look you might even remain the SU carbs.
Des Hammils "How topowetune over V8 engines" book is showing a classic 3.5Ltr eninge on SU`s with 220BHP.

this said, if you have a 2500 in "american" execution then a european TR6 engine with a mild cam and some webers might be ok as well.

it also depends were you mainly drive? long distances, also with motorway sections were rev´s should be within a reasobale limit ? do you have an overdrive gearbox fitted? if no motorways or seldom....the cheapest tuning woud be a shorter diff.--> better acceleration --> more fun.

Edited by LLantrisant on Sunday 26th June 11:59

Artracing

Original Poster:

43 posts

62 months

Sunday 26th June 2022
quotequote all
I’m going ford on #2


anonymous-user

61 months

Tuesday 28th June 2022
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I would go lumenition every time. Its bullet aand heat proof in the distributor - I had years of grief with accusparks et al where the modules break down with heat and age and cause misfires that cant be diagnosed. Lumenition is fit and forget.

Mercdriver

2,632 posts

40 months

Tuesday 28th June 2022
quotequote all
Check online, American spec engine 104 bhp, UK version about 150. So the biggest improvement is to fit tr6 head or as I suggested have the head skimmed to make it higher compression ratio.

Get the valve seats replaced so you can use unleaded.

Electronic ignition is desirable from a reliability point of view but it will not make a great deal of difference to the HP.

Biggest bang for the least bucks as our American cousins would say