Mi16 Block Gti6 Head

[Spiky 37]

whats are peoples views on this?

 

is the gti6 block and better than the mi16?

 

i'm just thinking of ways to save weight and 25kgs'ish is a healthy chuck of weight to be saved here

 

if i did swap would there be any oil surge issues rememeber this is track car

 

or is it only the head that causes this?

 

or should i stay with gti6 complete fore reliability

[welshpug 1,662]

Ask cameron I think there are others that have built similar engines.

 

It will enable you to fit cams with far more lift @ TDC, for which in the stock GTi6 engine you'd need different pistons (and most likely a re-bore dependent on the condition of the block)

[Cameron 16]

Definitely worth doing if you ask me. Although they do bolt straight together, it is a major faff to get all the necessary bits and bobs done to get it to work. You'll need a mis-match of GTi6 and Mi16 parts which makes rebuilds expensive, but that's the only downside I can see.

You'll need mappable management, but I think you're already on bodies aren't you?

 

It isn't just the head that causes surge, but it is a major factor. If you fit the XU10 sump too then you'll stand an even better chance.

I've had the car on track and not had any issues, but it has had quite a limited amount of testing. I'm pretty confident that I won't have any major problems.

 

Makes good power too, mine was standard when it got mapped (Emerald management) and it made 176bhp. Its going in again soon with some cams and an EWP so hopefully it should show some decent gains. I reckon you'll see decent power on bodies.

[Spiky 37]

yeah i'm on dta s40 and TB's

 

my worry is reliability, as mine gets some serious abuse on track. and never gets any oil issues, i dont want to compramise that

 

if this would put any doubt in the equation, i wont bother

[Cameron 16]

Time will tell I guess, but if its as bad as an Mi16 I will be very very surprised. I can't give you a definite answer as I haven't really done enough testing but I'd imagine that if your GTi6 has been ok then you won't have any problems with this either.

[Spiky 37]

yeah 9000+ miles and 20+ trackdays

[welshpug 1,662]

one way to build such an engine that would save some cash I think would be to start with an XU7 donor, swap the head for a 6 one, swap the crank rods and pistons for XU9 ones.

 

then you'll have timing belt covers and timing belt, as well as engine mounts etc that are standard parts available off the shelf (headbolts etc too)

 

 

note I haven't done one of these yet, only a dry build with a 1600 crank rather than a 1900 crank.

[Spiky 37]

they may well be a good idea (i have no clue) but i dont want to put a "unknown" or a "it might be ok" engine no mater how cheap or expensive in my car,

 

if someone was to post saying i have done this and done 10_ track days on slicks or r888's then i would go that route,

 

cameron's is looking promising, so will wait to see results from his

[James_R 3]

For the cost to gain I'd just keep the 6 till the big ends die form mileage, then look at it.

 

If you really want to get over surge, put proper cams and solids in then limit the oil flow to the head, baffled sump and you'll be fine. Although an accusump might be a nice idea. There's also the thread form Nick about using 8v rods and modd'd Mi pistons to reduce oil isses further.

 

Plus the compression is perfect for big cams.

[Matt Holley 11]

If I were you I would leave it alone for now, you have a car you can use and it works, while you are having fun using yours for a while keep an eye on ash from TT and se how he gets on

[Dj_mini 7]

Having swapped from an mi car last year to gti6 varient this year iv still managed to loose 40kg's over the old car so this shows theres still loads of ways of losing weight with keeping the iron block.

You have a stong engine so id look at other areas of the car one by one to see what can be lost

[Spiky 37]

Cheers matt, i have been watching his

 

DJ,

 

you got msn or something? really need to have a chat with you

[crf450 0 1 Cars]

The differance in weight between the alloy block and liners against the cast iron gti6 block is 16kgs.

[Cameron 16]

That's a fair bit! Would be interesting to know what the difference of semi-complete engines is, since there is a large difference in the weight of engine mounts for a start. Every little helps.

[crf450 0 1 Cars]

That's a fair bit! Would be interesting to know what the difference of semi-complete engines is, since there is a large difference in the weight of engine mounts for a start. Every little helps.

 

There isn't, the engine mounts weigh more or less the same,althought the gti6 engine mount is iron and the Mi one is alloy the gti6 ones small and the Mi one is massive.

[Cameron 16]

True!

[welshpug 1,662]

are you comparing the massive gti6 aircon mount? or the slimmer early non-a/c assembly?

 

 

the XU7 is the same top arm as the XU10, but a different bracket to the block to anything else.

[Spiky 37]

got a picture of the xu7 mount?

[welshpug 1,662]

yep

 

 

bit on the left is the generic 306/405 top arm, bit on the right bolts to the block.

 

haven't yet got a decent one of it bolted to the block.

 

I know Colin Satchell has made a tubular steel mount for one of these engine blocks that would be significantly lighter which is in use on Alan Dixon's engine, though that is completely solid mounted, shouldnt think it would be too much work to adapt the design to suit a car that isn't a pure race car.

Edited June 9, 2009 by welshpug

[PaulJLLD 0]

Whats the weight difference betwen a mi16 and a gti-6 lump then with everything on them ready to go in without the gearbox would be nice to know?

[Cameron 16]

A lot. I don't have weighing scales for arms but I can tell you that there is a very large difference, I can just about lift a complete XU9J4 engine without gearbox, I couldn't even budge a JRS block with crank, pistons and rods. If the JRS block weighs 15kg more then I'd say the difference between complete units will be roughly the same as the components are all similar in weight.

[PaulJLLD 0]

A lot. I don't have weighing scales for arms but I can tell you that there is a very large difference, I can just about lift a complete XU9J4 engine without gearbox, I couldn't even budge a JRS block with crank, pistons and rods. If the JRS block weighs 15kg more then I'd say the difference between complete units will be roughly the same as the components are all similar in weight.

 

 

O.k thanks, I for one like the sound of a Mi16 / GTi6 Hybrid to go in my road rally car got a gti-6 engine in the shed and its very heavy to move. does the sump,head etc all swap over o.k. only thing that pops in to my mind is what head bolts and head gasket you use and which timing belt? mi16 or gti 6?

[welshpug 1,662]

XU7JP4 belt kit, belt covers, head bolts should do the job

[PaulJLLD 0]

XU7JP4 belt kit, belt covers, head bolts should do the job

 

 

Ha yeah o.k thanks, sound like a project coming on now, Just need a good MI16 bottom end now. Anyone. um Better get the roll cage fitted first though.

Edited June 17, 2009 by PaulJLLD