Engine choice

[MartinClan]

I am considering building a Corsa Spyder which is based on Triumph chassis. But I would like to use something more interesting than the Triumph 4 pot engine.

Suggestions please ☺

It needs to be reasonably lightweight and readily available. Preferably with carbs rather than injection to fit with the look and feel of the car. My list so far:

Mazda Mx5 - did that run carbs?
Dolomite Sprint
Lotus twin cam - probably too expensive
Coventry Climax - probably too rare and too expensive
......

Cheers Robin

[Lucky@LeMans]

If you want to stick with the 4 pot options you can add these to your list;

Toyota 4AGE Twin Cam
Lancia / Fiat Twin Cam
Toyota Yaris VVT

I was really impressed with the wifes 1.3 VVT Yaris, went like a rocket. There are loads available and they're a cheap car to buy complete so you will get everything you need. Not sure about gearbox options but I'm sure there will be adaptor kits out there.

[keith]

Alfa did a nice 2lt engine with carbs rear wheel drive

[Grey V8 Pete]

Go for the Mazda mx5 1.8 fuel injected engine. My son has one in his Eunos. Goes like the wind and flexible too. Fit a decent air filter with a cold air supply. Have a look at the link below. Peter.

https://www.evo.co.uk/mazda/mx-5/153...mazda-mx-5-mk1

P S Lots of good spares available at mx5 parts too. Peter.

[Lucky@LeMans]

MX5 is probably your best bet. Plenty of rusted out MX5's to choose from. Buy a complete car so you can transfer everything across you need.

[Car photographer]

Cool that you're thinking of a Corsa Spyder ..... Do you think the vitesse or GT6 6 cylinder might work .... That way there'd be less issues when registering it if the engine is on its original chassis, and if you'd got a GT6 one the rear suspension should handle better too .... Only thing I'm not 100% sure of is the room in the engine bay, but looking at mine I reckon with a radiator moved forward a bit it could be possible

[Mick O'Malley]

The engine of my choice would be the one that achieved a class victory at the Le Mans 24 Hour Race. Although it had the 1147cc bottom end, the cylinder head was the eight port prototype of that which was introduced for the 1296cc version, and was retained for the 1498cc.

The engine in question? Watch the video.

Regards, Mick

[MartinClan]

Originally Posted by Car photographer

Cool that you're thinking of a Corsa Spyder ..... Do you think the vitesse or GT6 6 cylinder might work .... That way there'd be less issues when registering it if the engine is on its original chassis, and if you'd got a GT6 one the rear suspension should handle better too .... Only thing I'm not 100% sure of is the room in the engine bay, but looking at mine I reckon with a radiator moved forward a bit it could be possible

Yes - I am considering the Corsa Spyder with Triumph straight 6 lump but it's a bit of a heavy old beast... I found pictures of at least one Corsa that already has been fitted with the straight 6.

The rear suspension on the GT6 used rotoflex in the Mk1 and MK2 but thelater MK3 reverted to the swing spring. However.... There are kits arround to convert the rear suspension to using traditional driveshafts with "normal" UJ's. Apparently its almost impossible to get good rotoflex couplings (rubbish copies only available) nowadays so I would probably consider going this route.

We wait and see. I am only at the planning stage so far....

Cheers, Robin

[Car photographer]

Yeah I've heard the universal joints could be good, .... My old Gt6 had the rotoflex system .... Handled much better than my spitfire but were a nightmare to change

[froggyman]

The best permanent solution is the CV type replacement. I have not tried them myself yet as I am still in the planning stage for a Triumph based build. https://rimmerbros.com/Item--i-RG1314

[Mister Towed]

I wouldn't get too hung up on the rear suspension components, what works best on a full weight car won't necessarily make much of a difference on a lightweight car like the Corsa Spyder.

My Spyder was on Mk1 Vitesse swing axles with 'short' driveshafts and ran a Vitesse straight six in the stock position. After much experimentation it handled beautifully on the road with the following setup:

Soft springs - I removed the three small leaves and one large one from the rear spring and used 180lb Spitfire springs on height & rebound adjustable shocks up front with standard dampers at the back. Harder springs might work on the track but will slow you down on a bumpy back-road as the tyres won't stay in contact with the road.

Vertical wheels - I ended up with all the wheels completely upright with no camber at rest. That was achieved by removing the rear leaves as above and setting the front shock height so that the lower front wishbones were parallel with the ground.

Toe in/out - I removed some shims from the rear trailing arms to give it some toe in at the rear for directional stability, and dialled in some toe out on the front wheels to give it turn-in. I didn't ever check the number of degrees, I just adjusted it until it felt right on the road.

Tyre choice - I found that the tyres made a huge difference to how the car felt on the road, with high-profile (175/80/14) Uniroyal RainExperts giving a compliant ride, great grip and confidence inspiring turn-in. Oh, and don't worry about tyre wear, the car won't be heavy enough to scrub out its tyres during even spirited road use.

Good brakes - I put a servo (from The MGB Hive) on the single-circuit Vitesse brakes and fitted grooved discs and 'Greenstuff' pads up front with standard drums & shoes at the back. Worked a treat.

Ultimately, just remember that you're not setting up the suspension on a Spitfire or Herald, you're setting up a much lighter car with a lower centre of gravity, so you can expect to end up with settings that are quite different to factory spec for the donor car.

Good luck and have fun!

[MartinClan]

Originally Posted by Mister Towed

My Spyder was on Mk1 Vitesse swing axles with 'short' driveshafts and ran a Vitesse straight six in the stock position.

It's good to know someone else on this forum has already built one with the 6 cylinder engine. Were there any issues squeezing it in?

Cheers Robin

[Mister Towed]

Sorry, should've made it clear but mine was a Sammio Spyder. I'd post some pictures but photobucket are holding them all to ransom

[Mister Towed]

There are ways to shoehorn a straight six into pretty much anything that's already running a Triumph 4 pot:

Swap the front suspension turrets side to side - that moves the engine mounts back about six inches.

Fit a Spitfire/herald front engine plate to the motor instead of the straight six version - that gives you engine mounts just behind the front pulley (they're on the side of the block on a straight 6) moving the engine back about six inches.

If using standard engine mounts, raise the rear gearbox mount an inch - that will lower the very front of the engine by about 15mm through the 'see-saw' effect if you really need the last fag-paper of clearance under the bonnet (Phil J did this with his green Sammio Spyder).

Remove the top generator mount, rotate the generator around the lower mount (making it the top mount) and fabricate a new lower mount to keep the generator in place - that allows a tighter bonnet line over the distributor side of the engine.

All of the above will have knock-on effects like exhaust manifold and pipes clearance, gear lever location, possible bulkhead or chassis fouling, etc., so it's just a question of trial and error. In fact, I'm currently putting a Spitfire 4 pot under the front hood of a Porsche 356 replica (yes, really), and to get it to fit I have moved the engine back 90mm by fabricating new engine mounts and fitting an overdrive prophsaft to a non overdrive gearbox.

Or you could just modify the bonnet with scoops and bulges to get it to wrap around the engine and ancillaries.

In the words of the immortal Yoda, 'Impossible is nothing'.

[MartinClan]

For anyone else interested in the Corsa Spyder I found this U-Tube video.

https://www.youtube.com/watch?v=D8FO...ature=youtu.be

Check out the front and rear suspension. Not very Standard Triumph (pun intended) I would say. The engine is a six though, so at least it seems it will fit....

Cheers, Robin

PS - interestingly when checking out the registration number on the DVLA it is a Spartan - and Black

[Mister Towed]

Some nice design touches there, I particularly like what appear to be period alloy big drums at the front which I guess are hiding discs and calipers. I'd want them on the back axle too though.

[Biggles]

How would you get out of the thing with the handbrake on? It’s in the way of the door!!

[MartinClan]

Originally Posted by Biggles

How would you get out of the thing with the handbrake on? It’s in the way of the door!!

Haha. Yes I noticed that as well. I would say you could get out the other side but there is only a door on one side.

Robin

[Car photographer]

That engine would certainly be nice .... But apart from that I don't really like much that they've done to it .... Still think mine looks way better... (Front, lights, seats, rear, windscreens,etc) but I suppose I'm biased 🤔