Duncan's A30

[BiTurbo228]

Very tasty looking engine there!

Apologies for the continued thread-jack, but hopefully I've got some interesting points to add about various engines

MGC: The MGC engine is an interesting one really. It's predecessor in the Austin Healey is much loved by the racing crowd so it's interesting to try and work out why the engine fitted to the C gets such a bad rep. It's definitely heavier, but mainly on account of it having 7 main bearings rather than the Healey's 4. Remember reading a period account from folks rallying Big Healeys saying that they didn't want to push the engines any further than they were already unless they had a 7-bearing crank so the C engine should be exactly what they're after! The MGC version of the C-Series might weigh in the same ballpark as the Jaguar V12 (295kg), but the Healey version wasn't much lighter (271kg).

I know they suffer a little in port flow due to the head studs passing directly through some of the ports which is an issue. Hopefully they sort that on their crossflow heads! Still, [url=http://www.albionmotorcars.com/sold/detail/137/mgc-gts-sebring-1967-lhd]this chap[/url] seems to have got 195bhp from his with triple webers and a Peter Burgess head, which isn't a million miles from a hot 2.5l Triumph 6. Sure you should be able to get more from it though.

Rover 2600: Funny you should mention the Rover 2600 as I have one in my garage at the moment! Managed to buy it for £60 before they started getting a bit thin on the ground for bargains like that. The plan is that when I've finished the Spit6 with its Triumph 6 and driven around for a while I'll try fitting that and see how far I can push it.

I've looked into various details on it and it seems to be pretty promising. Still a 4-bearing crank, but of very rugged design with wide main bearings. Crossflow head with a good pent roof design. Very nice mahle steel-belted pistons on the 2600 version as well. The first bad bit is that parts are getting rather tricky to find. Things like main bearings and whatnot. There's probably solutions by pinching bearings from other cars, but I haven't looked into that yet. The second bad bit is that the cam profile is very mild indeed (purposefully blunted so as not to obsolete the Rover V8 version). Reportedly the de-restricted 2600s were making 151bhp/160lb-ft on twin SUs which is very respectable for an engine of that age and state of tune (the hotter cam was still not very hot). Not sure how much you can regrind the original cams, but I've got a brand new one somewhere to explore that. I have come across an SD1 racer with the 2600 that the driver said made about 220bhp (he was very happy to chat about it, I gather because it's a bit of a novelty for someone to head straight to the I6 SD1 and not the V8!).

The dimensions are interesting too. I've only take a few basic ones, but critically it seems to be the same height as the Triumph I6 from the base of the sump at the front to the top of the head (20"). The top of the head's a bit wider, and the dizzy sticks out the side of it, but it does sound promising for fitting it underneath a GT6's bonnet. The block itself is 1" wider than the Triumph I6 so that shouldn't be a major issue. The length may even be workable. It's 26" long (28" with ancilliaries) which is about 1" longer on both counts than the Triumph I6.

Looking at pictures of the block there seems to be tons of room for bigger pistons as well.

Without pulling my engine apart (I'll only lose the bits), it's tricky to find which ones might be suitable. The 2600 has a semi-heron head with part of the combustion chamber in a dish in the piston. So you'd need to find pistons with an appropriately sized dish to keep the compression right. I'd got as far as trying to work out the size of the dish in 1850 and 2000 slant 4s (and US versions of the latter) to see if they might suit. 1850 pistons would give you 2996cc and 2000 ones would give you 3228cc (or a very oversquare 2920cc usign the 2300 crank). Haven't worked out the size of the dish in the 2600 piston yet either (did order one when they were giving them away, but it got lost in the post). Oh, and not sure aobut gudgeon pin heights or thicknesses either.

Honestly I'm quite excited about the prospects of the last engine Triumph designed. Seems like it's one with untapped potential

Cross-flow head swaps: Another thing I've looked at for the 2600 is the possibility of fitting a Sprint-style 4-valve head to it. The critical thing here is whether the bore spacing is near enough to work. Haven't been able to find information online about the Sprint bore spacing, and I've yet to measure the 2600 headgasket I've got. Then it's a matter of welding two Sprint heads together, sorting a camshaft and sorting an arrangement for proper vertical head studs. This fantastically talented chap makes welding cylinder heads together look deceptively easy:

You know you have to temper your enthusiasm when the chap uses the same tone of voice when saying 'then, I weld the two heads together' and 'I put the bolts in the cam carriers and tighten them up'! 

I think the bore spacing is the thing that would be the trouble with the Triumph 6. It's really a very compact engine, and more modern (post-60s) manufacturers tend to make quite big sixes as they're rarely the budget end of the market. If anyone has a dead Triumph I6 headgasket they could post me I'd happily compare it to the 2600 one I have though as the blocks at least seem to be similar dimensions  motorbike engines might be another potential option, although they tend to have their cam chains running up the middle which is unhelpful.

[TimBancroft]

So Duncan, any news?

[michaeljf]

Hello Duncan, I'm with Tim!  Any news/Progress?  Regards, Michael.

[A30Racer]

My apologies for the lack of news on the little ol' A30. Progress has been mainly getting the front suspension trial-fitted, then taken off for painting. The underside of the body has seen a few coats of paint too. Going to be BMC Tweed Grey, which is light enough not to amplify all the imperfections and look suitable innocent.

My lovely girl, Victoria is getting involved which is good in many ways

[Nick Jones]

Good to see some progress Mr S......

Some of the best cars are grey! 

[A30Racer]

I can't disagree with that Nick! That primer look is never going out of fashion!!

[michaeljf]

Hello, Can't disagree with either of those comments. Good to see someone is having some progress!  Hoping everyone has a more progressive year ahead! (in all directions) Regards, Michael.

[Nick Jones]

4 hours ago, A30Racer said:

That primer look is never going out of fashion!!

Back fashion at present.  I'm only ever in fashion by accident 

[A30Racer]

The progress on the little Austin had stagnated of late due to things needed to be done on the house. Finally had a few hours free to re-aquaint ourselves with it. Today's efforts were painting the engine bay and the underside Tweed Grey and the suspension bits Satin Black. A long way to go, but progress is progress

[Nick Jones]

Good to see progress 

We don’t mind a Caterham thread either 

[A30Racer]

I'll get my people on to it very soon.....

[A30Racer]

Busy weekend on the ailing fleet of junk mobiles! Victoria has done some stirling work on the old A30. She has painted all the underside, inside the boot and the passenger interior. This is just brush painted, as it is mostly for rust prevention (it is a competition car & not going to be going anywhere near a concours arena). We will spray the outer bodywork when the weather is a bit warmer.

Should be able to start putting the running gear back in soon, so it car be rolled around. Hope to start building the big garage at home soon, so we can beaver away in the evenings, as access is a bit tricky where we keep it at present

[michaeljf]

Hello, That's looking pretty good.  I will have to get serious with my posted project.  Regards, Michael.

[A30Racer]

Been a bit lax on the updates, but progress is plodding on with the A30. All underside areas have been painted and it will hopefully keep the ferrous oxide at bay for a while. The suspension at both ends is now fitted and looks purposeful. No lever-arm dampers fitted now. 

[Nick Jones]

Progress!!

Rolling soon 

[A30Racer]

That was the plan to get it down off the roll-over frame today, but frankly it's too bloody cold outside & snowing. Clearing up the house suddenly looks like an attractive option..........

I picked up some Revolution wheels for the A30 this week, which will be fun to try them on. They came off an A35, so should be somewhere right. Want to put the engine/gearbox back in soon to see how much (or little) ground clearance we have with the racing springs. Still undecided if the fuel tank can in the original under-boot position or if it needs to go in the boot (I have a 4 gallon tank for that option). 

[michaeljf]

Hello, A lot of work so far. Trust the "road" ahead will be smooth and nor overly time consuming!  All the best (will be watching this space). Regards, Michael.

[michaeljf]

Hello, Any unreported progress? Regards, Michael.

[michaeljf]

Hello, That busy you havn't got time to report I hope. Regards, Michael.

[Nick Jones]

To busy playing with (and racing) the Caterham……

[michaeljf]

Hello, ....Well so long as there is a good excuse... (not that I can point a finger..) Regards, Michael.

[michaeljf]

Hello, Well mine has made a noise, what is happening here or even what is happening instead? Regards, Michael. 

[Nick Jones]

It’s still that Caterham, as above……

[A30Racer]

Sorry its been a bit short on updates for the Austin. Been busy with the Caterham & bought a 1992 VW LT motorhome. 
There will be progress over the winter once the big garage is built. Concrete for the floor is being poured today.....

Updates will follow.......

[michaeljf]

Hello, Glad to have an update. Looking forward to your reports. Regards, Michael.