Tuning project from Italy, Short stroke project for turbo app Options

[Victrix1975]

Hello!

I'm Antonio frome Rome; I've bought a nice 914 1.7 litre.

So I started this tuning project.

The basis is to start with the
DPR 66mm counterweight crank (55mm bearing)
I think is better have large rod bearing for turbo modification.
And with turbo is not so important have big displacement.

So in the reason of this I have some question.....

1- Chose of the piston and barrel; I think to use the 98 mm je piston and biral barrel
from AA performance, they build this kit for long stroke crank 78/86 mm.
So to fit correctly the piston which length of rod I'need? Could you advise me if
exist one with 55 mm bearing for typ 4 engine with adeguate lenght?

2- Is really recommended to not go over 98 mm bore? with 103mm bore the case
could crack? I'do not have experience on typ 4 to say which is the limit.

Hope everyone can advise me the better chose....

tanks

Antonio

[veekry9]

http://www.ooyyo.com/italy/used-porsche-91...1D6617C9864111/

Welcome Antonio. (IMG:style_emoticons/default/smile.gif)

This is the right place,and the right questions.
The heads should be rebuilt with new seats,guides,and valves if they are not cracked.Probably have to split the cases to re+re the bottom end.
"Tuning"these 80hp engines requires some delicate work,there are many aspects to them that are unlike any other.
As for rod length,depends on stroke and pin height,the variable being the deck height and desired head clearance.
A ton of lira can be poured into these engines,6K$ for a mild build,up from there.My own opinion is to build for reliability then add a nice turbo and intercooler. (IMG:style_emoticons/default/biggrin.gif)

http://www.914world.com/bbs2/index.php?showtopic=248774

http://www.914world.com/bbs2/index.php?sho...9&hl=nein14

Perhaps you've built a motor or two,if so where do you want to take your new Porsche 914?

Oh yeah,have a good close look at the TX,buy the Dr's video.


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[veekry9]

LN has the cylinders you may want to consider.

http://lnengineering.com/products.html

and for the heads to go with them http://www.hamincgroup.com/type4.php

As with all high performance engines,"How fast do you want to spend?"

http://www.thesamba.com/vw/forum/archive/i...t-286041--.html
In answer to the crank question,you are not the first to be there.
Bang for buck,it's hard to not go the big engine route.

[SirAndy]

Moved this to the garage for more exposure ...

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