Couple of queries

[minitravellerman]

I'm building an engine for the Traveller and I'm looking for some feedback on a couple of queries if you could help me out.

The engine is from an MG 1300 11 stud unit and will be mated to a rod change gearbox - I have already modified the floor of the Traveller for the rod change as I am currently running full 1984 Mini City running gear (minus the later subframe obviously). I'm probably keeping the unit to standard bore and will be getting a little bit of head work done (skim, polish and ported), although the block may get a +20 bore.

Query number 1 - carburation
(a) I have the twin 1.25s from the MG 1300 but they need fully rebuilt and refurbished
(b) I'm running a single 1.5 on the 998 and it's an excellent carb
(c) I am considering a 40 Weber on a short manifold so the bulkhead won't require modification.
Which would be the best foot forward on this matter do you think?

Query number 2 - gearing
I am hoping to use the Traveller for long road trips through the mainland and the continent, including motorway driving. Is the 3.44:1 diff currently in the 'box I'll be using suitable for this, or what diff would be recommended.
Also I'm considering s/c drop gears - is this just a pointless waste of money just to get some noise??

Looking forward to your comments.

[guru_1071]

pair of 1 1/4's and a 3.1:1 diff would be perfection.

[Lord Croker]

I wouldn't regard S/C drop gears as a waste of money, in any respect as they are stronger & more durable than helicals, I used a set for years in my Cooper S & never had a problem with them. However, you really have to like that noise, as unlike the S/C gearbox, there is no respite from it in 4th gear. It never bothered me, & I suspect it would be less dramatic in your traveller as you probably have full interior trim. My trim was a coat of matt black paint!
I'm in total agreement with Guru as regards the rest, I ran a Mini with that configuration on a 1300 GT engine & it was superb, loads of torque & would cruise on the motorway all day, very economical as well.

[guru_1071]

I wouldn't run sc drops in a road car as they really are noisy, they are less stonger and durable than helical ones as well, as the tooth forms are not designed to mesh smoothly together (which is what the helical ones are designed to do) the primary function of sc drops is to create a set of drops that can be swopped around to alter the ratios easily and cheaply, at the expense of noise!

the noise would just drive you daft!

[IAIN]

I agree with Guru. If you are after a car to do long runs with the less revs the better.

I have a woody like yours I fitted a metro 1.3 A+ standard engine because they idle smoother and quieter than the MG. I converted it to take a remote box and I fitted a 2.9 FD in it.
It won't break any records for accelaration but it is a pleasure to use and will do 80mph on motorways all day long easy.

You MG 1300 will be a lot less smooth than a 1.3 A+ in standard spec.

[InimiaD]

I'll be using a 1300 GT lump in my woody,if and when I get the time to finish it.
It's been built for reliability rather than out and out power with bags of bottom end torque to be used as and when required.
Spec is + 20 bore, Piper 270 cam, (virtually same spec as SW5), mildly ported 1805 head 1.5 ratio forged rockers, lightened flywheel and backplate. Later A+ rods were used because they are a lot lighter. (compared to 1300 A series rods).
Everything was then balanced.
Probably use a MG Metro HIF 44, but not sure on that yet.

A+ box with standard ratios and a 3.1 diff should make the longer trips a bit more bearable although Iain's 2.9 diff would be a better option for cruising on the longer runs. Shame I haven't got one spare now.

[Vegard]

If you use the 1300GT, be sure to get rid of the monstrously heavy flywheel. Have a lightened one from Rich:

http://www.minispares.com/product/Class ... .aspx|Back to search

Balanced with a lightened backplate and fitted. (Yes, you can have it balanced on a different crankshaft for this application)

Don't understand why a 1300A+ unit is so much smoother than a 1300GT though....

[Lord Croker]

I forgot to mention that my 1300 GT was fitted with an 850 flywheel, the other thing was far too heavy, also I was not clear about S/C gears, a gear is as strong as you make it, but weight for weight a S/C transmission system is stronger because it doesn't have the end thrust element that chews bearings up. That's why virtually all serious competition cars run S/C gears. However, looking back to the days of the Rolls Royce Merlin, the only gears that gave significant problems were the only helical gears in it, those (known as skew gears at that time) that drove the magneto drives. Everything else was driven by S/C gears. Now, that's what I call noise!
Vegard, I don't know why, either, but my 998 A+ is much smoother than any 998 A-series I've ever known, (excluding balanced ones)

[IAIN]

Don't understand why a 1300A+ unit is so much smoother than a 1300GT though....

Vegard, I am not in any way the best to explain the differances between A and A+, but years ago when fitting an old 1300 A series I remember it being a vibrating harsh sounding unit but good for the time. compare that to an A+ and the A+ feels a lot smoother and far better in my opinion.
Also the A+ didn't burn oil as much. ( excluding the early 80's 1.3 )
I am only comparing standard engines not modified in any way.

My understanding is that the A+ was balanced more from new.

[Spider]

My own experience with A vs A+, I've found the A blocks, just before they went over to A+ to be the best blocks in 1275's. The early A+ were little short of rubbish. The grade of CI wasn't terribly clean, nor were was the metal held at the critical pouring temperature long enough before pouring. The machining was also dreadful. The later A+ were considerably better.

[andy1071]

minitravellerman,
If you are not looking for too much performance (running a near standard camshaft, for example), I would suggest using the single 1 1/2" SU. -Easy to set-up, and good for economy and torque.

Regarding gearing, I would suggest a 3.1 or even a 2.9 diff.
I think with a carefully assembled engine, and a nice light flywheel (if everything is well balanced, I'd say 'the lighter the better'), the engine would be really sweet.

I used to have a Cooper Sport 500, which has the 2.7 diff. It could pull that no problem.
-But at 30mph in town, 3rd gear felt a bit low, and in 4th it tended to 'bog-down' a bit -it was right at the change-point. Whereas the cars I've had with a 2.9 diff (and very tuned engines that shouldn't have worked with it) were ideal, pulling 4th gear in town no problem, and good on motorways as well.

The last car I had with straight-cut drop gears, was not good for long distances (driving to and from Sweden), -It was fully trimmed, and I still needed ear-plugs!!
-Though it was great to blast around locally...

[minitravellerman]

Thanks folks - well since putting up this thread I have left the engine with Mervyn Johnston (the Tullyhommon Flyer) to build the engine for me. For those who don't know of Mervyn, he is legendary in Northern Ireland for his rallying skills in a Cooper S and for his Manx engine builds. I have given him all the gen on what I'm looking for from the engine and he is building it accordingly for me. Gonna be sweet!

[nick@dunsdale]

I ran a 2.9 diff raided from a mini city e , the city e as far as I am aware was the first mini to be fitted with this diff ratio.

It was a very nice drive if I was running ten's I would fit one again it was also a 1300gt that I ran the 2.9 on

[minitravellerman]

I ran a 2.9 diff raided from a mini city e , the city e as far as I am aware was the first mini to be fitted with this diff ratio.

It was a very nice drive if I was running ten's I would fit one again it was also a 1300gt that I ran the 2.9 on

Ok cool. I think I have a 2.9 diff under the work bench. Obviously I'm running 10s on the Traveller, so will look into that.

[guru_1071]

Mervyn Johnston (the Tullyhommon Flyer) to build the engine for me. For those who don't know of Mervyn, he is legendary in Northern Ireland for his rallying skills in a Cooper S !

mervyn is also a proper gentleman, very modest about his achievements and skills behind the wheel - he is still capable of showing a very clean pair of heels to far younger drivers.

I often think that with the right introductions, he would have been a works driver, and a very good one at that.

[minitravellerman]

Mervyn is also a proper gentleman, very modest about his achievements and skills behind the wheel - he is still capable of showing a very clean pair of heels to far younger drivers.

I often think that with the right introductions, he would have been a works driver, and a very good one at that.

I've often thought the same thing. He still can handle his 'S' well and still can show the younger drivers and those in quicker cars what's what.

I'm looking forward to see what he can do with my engine.

[minitravellerman]

Picking up the engine from Mervyn Johnston this evening. Hopefully won't be too long before I have it sitting in it's new home in the front of the Traveller!

[InimiaD]

That was quick.
Bet you're looking forward to the extra grunt.
What spec did you go with eventually.?

[minitravellerman]

Not going mad with the spec at all - basically mostly standard in the end. The bores were too badly scored to hone so Mervyn did a +20 bore so it's now 1293. The crank was perfect - only cleaned and fitted with new bearings. He replaced the cam with one from an MG Metro and changed the primary gear so the engine can be mated with a rod change box I have with a 2.9 diff. The head was good so no skimming needed - valves were reseated and new double springs fitted. Other than the ports given a polish that's it.
It's not going to set the road on fire but will be nice to have a little bit more grunt under the right foot.
He's going to rebuild the twin 1 1/4" for me as well.
As soon as the last show of the season is over the Traveller will be into the garage for her heart transplant! So come Spring time all the upgrades will be done and ready for running in - my plan is to drive to the 2014 Goodwood Revival (1200 mile round trip).