1600 8V, Mi Piston Fitment

[309jazzpanda 39]

Morning all, I have recently dropped onto some cheap mi16 pistons

Now I am sticking 1600 for class reasons and not going 16v because we discussed this idea and it worked out mucho expensive. So will the mi pistons just go straight onto the xu5 rods or will the little ends need work? I am aware the 8v is interference fit in the piston.

I am hoping to couple them up to a slightly worked head with 3 angle seats, 285 cam with vernier and obviously better valve train, exhaust wise I have a few choices at work, I know the jetronic is going to hate me for this new compression but motronic is just so hard to find now.

[309jazzpanda 39]

Really? not 1 person can help

Edited June 25, 2013 by 309jazzpanda

[dcc 855]

its been covered before, I haven't searched. but the engine it was done to came up for sale recently iirc.

[309jazzpanda 39]

I know spoox did a 1600 16v cut wasn't sure whether they needed special rods. I tried a search but couldn't reallx find anything that answered.Any ideas on compression?

[Tom Fenton 1,526]

Surely the compression height of the pistons will be wrong for the rods?

[309jazzpanda 39]

Well thats what I want know but don't seem to be getting by answers

[welshpug 1,626]

I wouldnt call it "wrong" but it sure will be differenf as the top of the piston is flat bar the valve reliefs.

 

You need to confirm the dish volumes of xu5ja and 9j4 and calculate the difference in compression.

 

From memory the 9j4 dont come quite flush to deck, dish/cutout/deck clearance of 2cc, designed for 1905 cc and 40cc head chamber and 1.4mm thick 83.5mm bore gasket.

 

8v chamber is 32 cc, similar 1.4 mm gasket, again, off the top of my head.

 

To make then fit XU5/7 conrods theres two ways, heat the rods and cool the pins

 

Or get small end bored and bushed, but theres not that much material to do this.

Edited June 25, 2013 by welshpug

[309jazzpanda 39]

Hmmm, so my idea of a high compression 1.6 may not be a simple case of put mi pistons on rods and all is good. I mean will it work with the 8v head

Edited June 25, 2013 by 309jazzpanda

[309jazzpanda 39]

Any ideas, I don't think I can stall the seller box longer

[mollisk 2 1 Cars]

To fit MI16 pistons to XU5 rods you will have to get the small end bored and fit a bush to suit the floating MI gudgeon pins. In addition the width of the rod at the small end will have to be reduced to allow the piston to fit.

As an alternative flat top pistons are available which will fit directly onto XU5 rods ( from a 1.9 SR ?? ).

 

 

regards,

 

Mollisk

[pug_ham 241 3 Cars]

As an alternative flat top pistons are available which will fit directly onto XU5 rods ( from a 1.9 SR ?? ).

To up the compression ratio on a 1.6 engine, this will be your best be bet & as said, they will fit directly onto the XU5 rods.

 

g

[309jazzpanda 39]

Thanks guys