Help. Where to start Mi16 build?

BG5WRC

Member
Fellow Frogger
Joined
Nov 15, 2010
Messages
204
Location
Perth
Hi All.

Hopefully I can get some local help - or at least Australia (rather than me trawling UK site) for advice on parts, best base engine and what combinations of parts will work for a hi-spec Mi16 engine build?

Literally willing to admit that I don't know where to start.

There is a 405 Mi16 engine for sale a couple of suburbs away in a sorry state. What do I check to ensure it would be a good basis for this build?

Thanks.
 
First thing to do is decide if you want the 1.9L alloy block or the 2L cast iron block. While the alloy is lighter, they are slightly more difficult to work with due to the wet liner engine design, changing the head gasket for example requires more precision and a little experience doesn't go astray.

Best thing you can do for either engine is a lift in compression. If you grab a cast iron 2L engine, then you have a couple of options to lift the compression without spending heaps.

Then you should speak with Peter Taylor on this forum, or visit his website Taylor Engineering and he will sort you out with cams to get the most out of a standardish engine.

If you're prepared to spend more money, there are options for later model inlet and exhaust manifolds, or go all out and run a set of quad throttle bodies. The XU engine is an excellent piece of engineering, compression appears to be about the only compromise that was made when these cars were sent into Australia. Sort that out and they are a lively, fun engine to drive in the right car.

There are a number of serious engines represented on this forum, and a number of pretty serious competitors. Take a look through and find some links to video of 205s going mad on the track.

What are you putting this engine in?
 
As said above, the increase in hp & torque from a 2L block more than compensates the weight difference with a 1.9L alloy block. A 1.9L head on a 2L block is the easiest build.
 
Hi. And thanks for the responses.

Might be a silly question, and I will google next, but there are some visible differences between the alloy and cast block. The one I am looking at locally is out of a 405.

Keen for the whole hog, forged bits, ITB, suggested standalone ECU's - i.e. spec me the ultimate 2l engine - assuming its not stupendous dollars I'll listen.

The intention is to use the car for Targa Rally, so lets assume it can rev high - but a limiter might be put in for longevity during those mad moments.

I'm in Perth, I have just bought - and it has arrived today - a 205 SI from Adelaide ~150k on the clock, so the body is good. It's auto too, so looking at options for the manual swap too.

Cheers.
 
First things - to identify the engine, if it has a curved alloy looking intake manifold, it will be the alloy block, if black plastic looking device the 2L cast iron block. see photos below (not mine)
series1.jpgseries2.jpg

Next, engine internals. Get ready for some big numbers.
If you really want a fully forged engine, then look at:
Steel crank from Farndon Engineering - they made the supertourer cranks back in the day. They can also make you con rods to suit. The crank will set you back about 1500GBP.
Pug1Off have an arrangement with Farnon and can sort out a rotating assembly with crank rods, flywheel.
Lots of options with pistons, but a decent set will start at about $900. Wiseco, Iapel, Wossner.
The head on a the Mi16 engine is an amazing thing. Don't be tempted into huge work to install bigger valves, it really is barely worth it. Really big cams on the XU9 engine need some additional machining in the head to allow the lobes to clear. If you get a head off a GTi6 they have bigger journals and more space so you can go crazy with cams. CAT Cams in Belgium have a big range, but Peter Taylor is the guru and might help you match things up to his cams for a more surefire outcome.
Throttle bodies are a matter of personal choice and your own ability to fabricate. You can go straight to Jenvey in the UK to get a nice set including manifold. Again, don't be greedy with throttle size, keep them as small as you can to make the horse power the engine is capable of. Bigger is not better, it just hurts mid range torque if the throttle velocity is too low.
Injectors are then chosen based on cam and throttle body combination + inclusion of a cam sensor to determine if you will set up batch injection or individual injection.

For reference:
alloy block = XU9J4 engine
CI block = XU10J4 and variants
GTi6 = XU10J4RS (different valves and top end also slightly taller block)
 
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I love your enthusiasm but beware, the achilles heel of these engines is oil surge. For tarmac, you either need to throw everything at a wet sump + an accumulator, or dry sump it. Whilst the dry sump sounds like more work and is expensive, don't forget it also releases hidden horsepower.

Keep in mind that XU9J4 and XU10J4 heads are very similar. Whilst XU10J4R and XU10J4RS are similar. The cheapest hp/$ option is the XU10J4.

I'd buy a Colin Satchill inlet manifold and locally made tb's from EFI Hardware.
 
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Thank you @racing405 and @PeterT. I am genuinely appreciative.

I'm willing to admit when I don't know enough about something, this engine is one of those things.

That confirms that the local engine for sale is an XU9J4.

Sounds like it is worth talking to Pug1off for internal components, but do you supply the same gear Peter?

I like the sound of the 2l - I presume there is ability for slightly more torque? So the hunt begins for a XU10J4 - of which I notice an S16 for sale in Victoria...

Peter, your website ranked quite well in a google search the other week! You have quite a good rundown on the baffled sumps. I'll take your advice on oil problems on these. I would need to read the CAMS and MSNZ regs on dry sumps however.

I have been talking to Satchell Engineering about a few components, I'll ask about their inlets. Thanks.
 
With the Si you will need a GTi donor car to get the front suspension, Si suspension is very good for gravel competition on a standard car but for high power bitumen use you will need the A arm lower control arms and the cross member to go with them. Also the clearance around the rear wheels is less in the Si but not a huge problem to increase.

Thank you @racing405 and @PeterT. I am genuinely appreciative.

I'm willing to admit when I don't know enough about something, this engine is one of those things.

That confirms that the local engine for sale is an XU9J4.

Sounds like it is worth talking to Pug1off for internal components, but do you supply the same gear Peter?

I like the sound of the 2l - I presume there is ability for slightly more torque? So the hunt begins for a XU10J4 - of which I notice an S16 for sale in Victoria...

Peter, your website ranked quite well in a google search the other week! You have quite a good rundown on the baffled sumps. I'll take your advice on oil problems on these. I would need to read the CAMS and MSNZ regs on dry sumps however.

I have been talking to Satchell Engineering about a few components, I'll ask about their inlets. Thanks.
 
Thanks Graham. Have some plans in play for the subframe, and Bilstein dampers kit. None the less, the advice is good.
 
What capacity are you considering? Does it have to be strictly under 2L? Most rules allow for oversize pistons during reconditioning. Swapping cranks also increases capacity (and compression ratio).

eg
83x88 = 1905
86x86 = 1998
86.5x86 = 2022
87x86 = 2045
87x88 = 2093
87x92 = 2188

The cheapest and cheerful engine you can make is to skim 1mm from the XU10J4 block and run 86.5x86. With tb's, reground cams, thin gasket and dry sump, it will make 220+hp.
 
Where do you get the 86.5 mm pistons Peter?

What capacity are you considering? Does it have to be strictly under 2L? Most rules allow for oversize pistons during reconditioning. Swapping cranks also increases capacity (and compression ratio).

eg
83x88 = 1905
86x86 = 1998
86.5x86 = 2022
87x86 = 2045
87x88 = 2093
87x92 = 2188

The cheapest and cheerful engine you can make is to skim 1mm from the XU10J4 block and run 86.5x86. With tb's, reground cams, thin gasket and dry sump, it will make 220+hp.
 
Why not just buy my S2 Mi16? Excellent car, you could build the engine up run the car in some events then later put it into the 205.
Rebuilt front end Bilstein B6s all round.
Cheap, it has to go as I have too many other projects, I really don't want to part it out but it has to go.
 
Peter's comment about oil surge is surely true. I spun one set of bearings at Phillip Island and then put a dry sump on my '16. The sump unlocked between 5 and 8kw, which was surprising. That makes it expensive horse power but cheap security. The 306 I'm putting together now will have a dry sump, Pace in the UK do a kit but have been terrible to deal with lately.
 
What capacity are you considering? Does it have to be strictly under 2L? Most rules allow for oversize pistons during reconditioning. Swapping cranks also increases capacity (and compression ratio).

eg
83x88 = 1905
86x86 = 1998
86.5x86 = 2022
87x86 = 2045
87x88 = 2093
87x92 = 2188

The cheapest and cheerful engine you can make is to skim 1mm from the XU10J4 block and run 86.5x86. With tb's, reground cams, thin gasket and dry sump, it will make 220+hp.
Hi Peter.

220 would be nice. My question would be- which of these options are proven? One in ease of work and two in results.

Are you an engine builder? I might make more sense to give you a call this week.

Cheers.
 
Pace actually publish a retail price list, but the bits I'm buying are just about 1,100GBP. That's the sump, pump, drive kit and remote filter mount / block adapter.

On top of that you need a tank, filter head, oil cooler, thermostat (not essential) and all the pipe and fittings. Unlikely to get away with any change out of about $3000 AUD - so it is an expensive option. You can improve wet sump oil security without going all out with a dry sump, but apart from anything else, it makes the engine spec sound like it belongs in a race car.

My Mi16 turned into a prick to drive at anything below about 80km/h (steering and suspension not engine), but from the top of second gear through to 225km it all made sense and was just a real buzz to drive fast.
 
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