Billet Crank, Rod Lenght, Pin Height

[Guest Exhume.dk]

Good evening, Gentlemen

 

New to this forum, but have been looking here for advice and other topic along the way. Used the search, but haven't found what im looking for. Anyways, let me get to the point :

 

XU10J4 engine, with a 100 mm crank, and a Turbonetics GTK-550 .82 ratio

 

This is what i've found so far on the stock T16 (XU10J4TE)

Block height : 235

Crank 86/2= 43

Rod lenght : 152

Pin height : 35,50

__________________

 

total of : 230,5 mm

 

So it seems like a clerance of 4,5 mm before the deck, right ? Can anyone verify this rant ?

I never seen a Wössner/JE other piston live..yet, but many photos and they are all flat, no dome, no protrusion, just flat.

 

I know just buy it online @ Wössner or JE..as a Plug'n play package.

But:

 

The tricky bit for me is the 100 mm crankshaft,

I calculated a need of 145 mm rod for a "stock" Wössner T16 piston.

As the T16 i get the 4,5 mm clearance, to somewhat 8,0 : 1 i compression ratio. Or have i lost it allready ;-)

Perhaps in a 86,50 bore,I think i need all the help i can get for spool up, and the end result should be significant , hence the use of stock layout from Wössner

with the 23 mm pin dia. since many Opel/vauxhal also feature a similar size, but much smaller 21 pin dia.

 

I have a 88 mm billet also, wich can be utilized if the need arises, but i will down size to a 2043 ccm. from a current of 2322 ccm.

Yes i can properly rev even higher, but that issue is another story..later on.

Just want to know if i found the "sweet-spot"

 

Please advise or bring some input on this matter, am i missing something here

Been calculating back and forth now, so i hardly know what what anymore

 

Thanks

 

Christian from denmark

 

sorry for any misspellings

[B1ack_Mi16 67]

I would consider some proper rods and pistons for your setup.

 

If the 100mm crank has the normal 24.xx journal width for the rods you can easily use off the shelf H-Beam rods for the 2.0 Mi16.

152mm long.

 

Then just get some flat top pistons to suit the compression you want.

The pin height of the original T16 pistons are too high for a long stroke setup if you like to retain some length of the rods (which I would aim for to avoid low rod/stroke ratio).

 

You might even need to get dished pistons to keep compression under control due to the high capacity.

 

It's just a matter of calculating the compression and find out what components you need to buy.

 

But first just measure how wide rods you should use on the crank.

[B1ack_Mi16 67]

And if you decide to go for the 88mm more rev happy setup I would gladly have your 100mm crank

[Guest Exhume.dk]

And if you decide to go for the 88mm more rev happy setup I would gladly have your 100mm crank

 

Thx B1ack_Mi16

 

I had to kill someone to get it ..so it better stay with me

 

Anyways :

 

The off-the-shelf solution with the 2,0 Mi16 XU10J4 @ 152 mm sounds tempting, but the 100 mm crank uses other bearings, from BMW so i need to order a one off set, proberly from Pauter, and need exact messurements off course.

 

ATM it's with 100 mm crank, 155 mm rods and 30,50 mm pinheight, then the piston crown have been machined to flush the block, and a small dish also.

That comp.ratio is unknown, it's build that way by Agergaard for N/A, and all road applications are usaully at 11:1'ish so i understand.

 

 

The decompressionplate looks like a 3 - 5 mm lump,( not that i will use such a soluton) so i understand your point in 152 mm rods, insted of the 155 atm, and that's what im looking for, some kind of verification/experience on a turbo build.

 

The T16 has a 4,5 mm gap acording to Wössner data, and still with stock 8,0:1 and that same comp.ratio is what i need for a large turbo.

The Mi16 2,0 has 1 mm gap, so again it's a 3,5 mm difference. Allthough Wössner gives the piston crown a + 5,9 ccm increase to reach 12,2 in C/R over stock 10,4:1

 

The compression calculators on the internet need value i dont have, since it's not a stock engine, and because i dont know the stock chamber volume of a XU10J4R and a XU10J4, anyone got these data ? Then i can calulate the C/R and place an order with Pauter and JE pistons.

 

Cheers

 

Christian

Edited November 30, 2009 by Exhume.dk

[B1ack_Mi16 67]

Thx B1ack_Mi16

 

I had to kill someone to get it ..so it better stay with me

 

Anyways :

 

The off-the-shelf solution with the 2,0 Mi16 XU10J4 @ 152 mm sounds tempting, but the 100 mm crank uses other bearings, from BMW so i need to order a one off set, proberly from Pauter, and need exact messurements off course.

 

ATM it's with 100 mm crank, 155 mm rods and 30,50 mm pinheight, then the piston crown have been machined to flush the block, and a small dish also.

That comp.ratio is unknown, it's build that way by Agergaard for N/A, and all road applications are usaully at 11:1'ish so i understand.

 

 

The decompressionplate looks like a 3 - 5 mm lump,( not that i will use such a soluton) so i understand your point in 152 mm rods, insted of the 155 atm, and that's what im looking for, some kind of verification/experience on a turbo build.

 

The T16 has a 4,5 mm gap acording to Wössner data, and still with stock 8,0:1 and that same comp.ratio is what i need for a large turbo.

The Mi16 2,0 has 1 mm gap, so again it's a 3,5 mm difference. Allthough Wössner gives the piston crown a + 5,9 ccm increase to reach 12,2 in C/R over stock 10,4:1

 

The compression calculators on the internet need value i dont have, since it's not a stock engine, and because i dont know the stock chamber volume of a XU10J4R and a XU10J4, anyone got these data ? Then i can calulate the C/R and place an order with Pauter and JE pistons.

 

Cheers

 

Christian

 

Mi16/S16/T16 head chamber is like 40cc

The XU10J4R more like 38cc.

 

I expanded my chambers to 44cc on the Mi16 head on my 2.3 engine to get the compression under control.

 

I've done some rough calculations on a 86.5mm bore and 100mm stroke (guess you will rebore it to get fresh cylinders).

 

With Mi16 head 40cc and 152mm rods and flat top pistons with 30mm pin height you'll end up with 10:1 and pistons sit 3mm down the bore at TDC.

 

If you get 30mm pin height pistons with 9cc dish that will give you 9:1 compression.

 

Same setup with 13.5cc dish will give 8.5:1 compression.

 

And 19cc dish will give 8:1 compression.

[Guest Exhume.dk]

Mi16/S16/T16 head chamber is like 40cc

The XU10J4R more like 38cc.

 

I expanded my chambers to 44cc on the Mi16 head on my 2.3 engine to get the compression under control.

 

I've done some rough calculations on a 86.5mm bore and 100mm stroke (guess you will rebore it to get fresh cylinders).

 

With Mi16 head 40cc and 152mm rods and flat top pistons with 30mm pin height you'll end up with 10:1 and pistons sit 3mm down the bore at TDC.

 

If you get 30mm pin height pistons with 9cc dish that will give you 9:1 compression.

 

Same setup with 13.5cc dish will give 8.5:1 compression.

 

And 19cc dish will give 8:1 compression.

 

 

Thanks, much appreciated, you are a lifesaver

 

I'll look for a 100 mm next time, they tend to pop up for sale here and there

 

Oh-well...back to the garage rejuvenated

[opticaltrigger 52]

I think I follow what your saying.Personaly with a turbo application I favour a longer rod for a few reasons but the main one is that it reduces the piston speed giving rise to a much cleaner and smoother intake of the fresh charge and likewise for the exhaust cycle.

Also and often overlooked is the effect piston speed has on flame front propergation.It is quite possible with the right (or wrong) combination of parts to end up with the piston accelerating away from the igniting charge so fast that it can actualy outrun the effective pressure rise effectivley lessening the power output by not waiting around long enough to gain all the push from the cylinder pressure.

I cant remember the formula off the top of my head,you could easily look it up though.But a good bench mark to go by with rod ratio's is an overall ratio of 1.6:1.Thiss is a happy ballance of most factors especialy that of piston speed.

Do your calculations with thiss figure in mind.It's not a number thats set in stone but if you aim in that near vacinity you wont be far of the mark.

 

All the best

O.T.

[Guest Exhume.dk]

Thanks all for the input and considerations.

 

The end of this fase, the information gathering, yielded a 1,55 i rod/stroke since the stroke is 100 mm and rod 155. The ideal starts at 1,60.

I have a evil back-up of 1,82 so i can rev the jesus out of it.

 

Will be using the pistons of 29,20 mm. pin height so it will end up with = 50 + 155 + 29,20 = 234,20mm leaving a 0,80 mm.

 

The pistons are ordered, and looking forward to receive and make the final measurements /verifications.

 

Best regards

 

Chr.

Edited December 3, 2009 by Exhume.dk