Thanks Scottie, I've just posted a video over on your build thread that might interest you.

I reckon the K series conversion would be pretty expensive, £2.5 - £3.5k could easily be swallowed once you've bought all the parts necessary for the conversion, but I do keep looking at the old MX5 and wondering if the whole drivetrain would fit in a herald chassis. Can't seem to find any dimensions on t'internet though...

BMW M42 1.8i weighs 81kg @ 115HP on a 5 speed box @ 64kg (that's bl##dy good)
SHOULD GO VERY WELL :dizzy: :dizzy:

I can see the attraction of going for a more modern lump but I do like having an "age appropriate" drive train.......and running a distributor and carbs.

I know that I am not sticking to the ethos religiously, but I want to own a 1950s special. I hated it when Formula Ford went from Kent to Zetec......I'm just a miserable old git.

I second that...

I totally understand where you are coming from, but we have to move forward and try differant things.

The Triumph straight 6 is a heavy and slow reving engine, compaired with a modern engines what ever the make.
They are getting hard to find and expensive to repair/re-build, and lets face it most of them need re-building as there 30 or 40+ years old.

The modern engines on the other hand are plentyfull, cheap, reliable and as a bonus return good MPG.
We are very lucky in the UK as Triumph spares can be found, but thats not the case around Europe.

There's as much fun in driving these cars as there is in building them, but, I find with a little extra punch under the bonnet there's a little extra fun to be had.
I recently drove Spitfire with a Zetec fitted and it was so much fun I do'nt want to give it back!!!!

Still, each-to-his-own :thumb:

Was going to suggest a zetec as they bolt straight up to a type 9 and can be had brand new in a crate for about £600 to £700. Only issue would be that it would have to be a retro fit after the dvla inspection i think.

That should not be an issue. the DVLA says "an unaltered chassis and 2 major compontent" to retain the registration ie score 8 points and over, of the 14 points which makes up a vehicle.
Chassis= 5,
Axles= 2,
Supension= 2,
Steering= 2,
Transmition=2,
Engine= 1,
Total 14

But, it would be wise to have the replacment engine details ie; engine number and CC up-dated on the V5 before the inspection.

But again it's DVLA so anything can happen :tape:

Although I'd be tempted by a modern motor and five/six speed box if I ever decided to build a street/race Spyder, I'd be looking for an in-line engine and box from a cheap donor to keep the costs down, very much like Micky1mo is doing with the BMW four pot and box, which I'm watching with interest :)

The trouble with looking at a crated Zetec at £600 to £700 is that you then need to start shelling out on some very expensive ancillaries, like throttle bodies; megasquirt injection system; distributorless ignition; custom exhaust; etc, and the final bill can very quickly get out of hand. That's fine if your funds are limitless, but mine aren't. :(

Oxford's really hit the nail on the head too - these old cast iron lumps might be heavy, slow to rev and have a low specific output, but they're full of character, easy to work on and mine was effectively free as it came with a donor that cost less than I got from selling off the unwanted parts on ebay!

So, assuming you have any, which I don't at the mo, you pays your money you takes your choice...

I finally got round to starting on the secondary radiator at the back of my car today.

It'll only be needed at sustained motorway speeds - the temperature gauge starts to climb towards the red after running at 70mph for over an hour - but after completing the 400 mile round trip to Goodwood this year I've really been bitten by the touring bug. In fact I had planned to drive it down to the Exeter show at the weekend, but I didn't finish work until 3am on Saturday morning and the worst storm in decades was forecast for Sunday, so I had to abandon that particular plan :(

After lots of measuring and chin rubbing I bought an MR2 roadster radiator, which is suitably wide and short in height. Here it is with some brackets I fabricated from galvanised angle iron already bolted up -

http://i1301.photobucket.com/albums/...ps2fa9c3c4.jpg

And here it is bolted up to the now redundant rear exhaust hanger bar -

http://i1301.photobucket.com/albums/...ps84a05fc3.jpg

http://i1301.photobucket.com/albums/...psb077f65a.jpg

As you can see, it fits nicely in the space between the fuel tank and the back end without sticking out underneath.

Now, just the small matter of plumbing it in...

Do you think you might need an auxilliary water pump to help fluid circulate. BMW and Mercedes items might be appropriate. They go for about £25 on a well known auction site.

I'm hoping that the (new) Triumph one will do the job. There are no restrictions in the hoses, it's all going to be 32mm, so I've got my fingers crossed that it'll circulate just fine without an auxillary pump :pray:

Neat fit.
That's a large volume of water to push around.
An auxiliary pump and a shut-off valve might be a good idea otherwise getting the car to warm up might be a problem in the coming winter months. :idea:

Both radiators are downstream of the thermostat so warming up shouldn't be affected. We'll have to see about the extra pump...

It looks quite vulnerable to being damaged down there?

Was about to say that a stone flicking up at 70 woold damage it...a mesh screen may have to come into play I would have thought?

The older type of water pump is designed to circulate water not pump water, much like a spoon in a cup of tea. This is why its normally place in the centre of the mass of water it has to move ie; centre of the engine block.
Because of this (and past experience) I think your going to have problems :ohwell:

OK, sounds like I need to do a bit of thinking then. Perhaps a secondary electric pump and a control valve triggered by a temperature sensor might be in order.

By the way, what do you think's likely to happen if I don't boost the circulation?

Oh, and I probably will also fit a screen to protect it from flying stones, just like I did at the front.

I supect the volume of water in the system will be just be to"heavy" for the standard pump to move so you'll only get partial circulation and little heat transfer.
An air lock in the cooling system can cause similar efect because the volume of water is not equal either side of the circulating pump so no circulation.
Air locks might be another problem you have to deal with. :doubt:

What type of radiator are you running? is it an original 2lt radiator? can you not fit a better (not bigger) radiator up front, also a good oil cooler will help?

second rad
 

Mister towed,
I was reading about your second rad, and the problems you are facing.
I read some of the earlier thread to see why you needed an extra one and I've missed something.
So why briefly, why a second rad? I'm really curious .

I've fitted an aluminium radiator from a Honda Civic VTEC up front with an electric fan and in normal driving it's fine.

While running at motorway speeds for over an hour though, the temperature starts to climb rather alarmingly. It didn't actually overheat, but I don't really want to be driving it across Europe with one eye on the temperature gauge.

The problem is likely to be the amount of air being rammed into the engine bay behind the radiator through the large scoop in the bonnet. The scoop isn't cosmetic, by the way, it's there for the bonnet to clear the six cylinder engine. I don't really want a chin spoiler to drag more air into the rad, I think it would look terrible, and there isn't really anywhere to put an oil cooler that wouldn't obstruct the radiator, so I thought 'why not bung another radiator in the back?' as you do when you've built your own car.

It now seems that it wasn't such a simple idea after all, but that's one of the benefits of posting ideas on this forum, there's always someone who can give advice to stop you screwing up :hail:

So, as I've no motorway journeys planned until next year, job for today is to reconnect the original coolant hoses and leave the new rad dry mounted in the back while I save up for a Davies Craig water pump. :icon_redface: