Four cylinder engine swap

[Marco Polo]

I know this idea will horrify most of you!
It doesn't sit well with me either!

My son is approaching the age of driving lessons and his first car. To keep insurance and registration costs to a minimum a four cylinder powered car is the obvious choice. You can't drive a V8 or turbo powered car until you are 25 in Queensland.

We've been searching for a project car that we can restore together prior to him gaining his licence without much luck.

At the weekend he suggested that we get a Stag and swap the engine and transmission for a four cylinder until he we can put the original engine back in in 9 years time! It kind of makes sense and I wondering if any of you had seen or heard of any Stags with four cylinder engines. If so what engines were they? I don't want to do anything that can't be reversed easily.

My thoughs are for a TR7 or Dolomite sprint engine to keep the Triumph theme or a modern fuel injected motor, with a semi decent output upto120 bhp, but am willing to explore any ideas.
Thanks and regards,
Raoul

[KOY 23]

Hi Raoul.

Understand your logic and agree with your reservations. The only 4 cylinder Stag I have seen had a Ford Sierra 1.8 diesel engine. It would have to be RWD, so that rules out many moderns except the Omega, was there a Holden version? The 2.0 litre is a good engine. Or a BMW, must be plenty of those in the scrappers.

John.

[wilf]

Before you get too carried away emasculating a Stag, have you checked if modified/altered vehicles are acceptable to the registration authorities and insurers? Certainly, the combination of young driver and modified vehicle in the UK would make most insurers go pale. Or at least the person paying the premium.

[Guest]

I can't see the point of doing something like that. Why not just go and buy a bog standard cheap 4 cylinder car and get a V8 in 9 years time! I waited until I was 66 before I got mine!

But then again, I never see the point of buying a car and turning it into something else. However, each one to his own - it is his do do what he likes with.

[Marco Polo]

Before you get too carried away emasculating a Stag, have you checked if modified/altered vehicles are acceptable to the registration authorities and insurers? Certainly, the combination of young driver and modified vehicle in the UK would make most insurers go pale. Or at least the person paying the premium.

Hi Wilf,
Thanks for your input, modified cars are less of a problem here as long as you have an Engineers report. The annual registration fee is at least half that of a V8 and I've already been quoted AUD 1,200 pa insurance. The insurance companies are pretty good especially the ones that deal with classic cars.
I carry out the design and modification of aircraft and their systems for a crust and I have a close friend who is an automotive engineer, I can assure you the modification will not only be fully reversable but fully compliant with the relevant ADRs.
I wouldn't describe the engine swap as an emasculation, more a reversable vasectomy!
I'm pleased that my son has a passion for classic cars, especially Stags. My thoughts, and those of our closest friends, who know my son well, are if he puts his blood sweat and tears into a car that he loves so much he will be unlikely to wrap it around a tree.
regards,
Raoul

[Guest]

Having over the past few years seen our children obtain their licences and get out on the road by themselves, we like most parents are terrified of what can happen to our loved ones. For this reason we have made sure the cars they drive has as many safety devices as we/they can possibly afford. There is no doubting the desire to cruise the roads in o classic but I just feel a lot happier knowing they cars our children drive have ABS and that they are surrounded by as many airbags as possible. Having the right attitude is a fantastic start but inexperience still causes accidents.

[Stag therapy]

......
At the weekend he suggested that we get a Stag and swap the engine and transmission for a four cylinder until he we can put the original engine back in in 9 years time! .........

Will you not also have the problem of looking after the removed engine and gearbox for 9 years - turning it etc?

Baz

[wilf]

Raoul - thanks for setting me straight about the way mod'd cars are dealt with in Oz - and of course I never meant to impugn your own skills, oh no. Ozstag makes the other point I was thinking about but didn't include - modern cars with ABS, stability programs, airbags, crumple zones, etc. are probably the best bet for a young chap, certainly if they were anything like me, as I managed to bounce various cars off various bits of countryside for some time until I "grew up". And there is debate about the extent of the last point.

[new to this]

Raoul - thanks for setting me straight about the way mod'd cars are dealt with in Oz - and of course I never meant to impugn your own skills, oh no. Ozstag makes the other point I was thinking about but didn't include - modern cars with ABS, stability programs, airbags, crumple zones, etc. are probably the best bet for a young chap, certainly if they were anything like me, as I managed to bounce various cars off various bits of countryside for some time until I "grew up". And there is debate about the extent of the last point.

on my stag im fitting side impact bars to the doors

dave

[Andy Rundell]

Ignoring the 'don't do it' comments, if you are after a 4-cylinder alternative, but retaining the Triumph theme, plus getting plenty of practice for water pump and cylinder head removal techniques before refitting the TV8 the only choice is a Dolly Sprint engine

.......... Andy

[Ian Durrant]

Having over the past few years seen our children obtain their licences and get out on the road by themselves, we like most parents are terrified of what can happen to our loved ones. For this reason we have made sure the cars they drive has as many safety devices as we/they can possibly afford. There is no doubting the desire to cruise the roads in o classic but I just feel a lot happier knowing they cars our children drive have ABS and that they are surrounded by as many airbags as possible. Having the right attitude is a fantastic start but inexperience still causes accidents.

Somebody important once said something like,the best safety device that can be fitted to a car is a long sharp point sticking out of the steering wheel. If all cars had that there would be no accidents!

[jleyton]

Somebody important once said something like,the best safety device that can be fitted to a car is a long sharp point sticking out of the steering wheel. If all cars had that there would be no accidents!

It was Clarkson who said that . 'Important'? I'm not so sure but it's not a bad point - (pun not intended )

Cheers

Julian

[jleyton]

Ignoring the 'don't do it' comments, if you are after a 4-cylinder alternative, but retaining the Triumph theme, plus getting plenty of practice for water pump and cylinder head removal techniques before refitting the TV8 the only choice is a Dolly Sprint engine

.......... Andy

If Neil (flying farmer) can put a TV8 into a Toledo then I'm sure a Sprint engine could go into a Stag !

And at 127 hp, it's not a lot less than the Stag's 145hp. In fact, prototype Sprints were putting out 135hp - the car was going to be called the Dolomite 135 until the very last minute when they realised that they weren't all putting out 135 hp.

Cheers

Julian

[KOY 23]

Ignoring the 'don't do it' comments, if you are after a 4-cylinder alternative, but retaining the Triumph theme, plus getting plenty of practice for water pump and cylinder head removal techniques before refitting the TV8 the only choice is a Dolly Sprint engine

.......... Andy

And the N/S engine mount may be the same?

[flying farmer]

For ease of fitment a dolly sprint or TR7 engine is the way to go. The sprint gearbox is virtually the same as the stag so there would be no problems with the interior of the car, I think you can use the same mounts for the engine, the only problem is that the 4 pot vibrates rather more than the 8 at low revs. The TR7 sump has the correct rear pan.
I fitted the stag engine to the Toledo using a Sprint engine backplate and adaptor plate, as the Stags gearbox has its slave cylinder in the wrong place for the subframe, and the box also leans to the right hand side with the Stag, whereas the Sprint gearbox is upright, I had to redrill a couple of holes in the adaptor plate where it bolts to the block, so it may be possible to use the stag adaptor on a sprint engine to keep the box at the right angle
I once fitted a sprint engine to a TR6, just because I had one and wanted to see if it would fit, it was as quick as the straight six, handled better and would do 40mpg on a run! The worse part was making an exhaust manifold that came up and over the cam cover, and then back down the other side, as I didn't want to cut the bodyshell, and could link it to the TR's exhaust.
The one other thing you might need to do if fitting a 4 pot, is change the diff for a 4.1 ratio unit out of a 2000 saloon. I still had the 3.45 in the TR6 which with the 15 inch wheels, made hill starts a bit of a struggle, and because of the high ratio of first gear, tickover was too quick in traffic
Neil