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-   -   will a v4 sti engine fit in a v5 sti (https://www.scoobynet.com/general-technical-10/915572-will-a-v4-sti-engine-fit-in-a-v5-sti.html)

damotypeR 02 December 2011 07:23 PM

will a v4 sti engine fit in a v5 sti
 
in desperate need for a v5 sti engine but cannot source one anywhere , but would it be possible to fit a v4 sti block using my inlet manifold????????

Paulo P 02 December 2011 07:28 PM

The short motor will but not the long motor because the heads are different and your inlet manifold won't fit.

damotypeR 02 December 2011 07:34 PM

so a short block with v4 heads will fit , or will i need v5 heads cheers

Paulo P 02 December 2011 07:39 PM

No you will need version 5 or 6 heads with that version 4 short motor.

damotypeR 02 December 2011 07:47 PM

got ya thanks

Paulo P 02 December 2011 07:49 PM

or you can source a version 6 engine :thumb:

damotypeR 02 December 2011 07:54 PM

can seem to find any other engine except one that will fit mine

Paulo P 02 December 2011 07:59 PM

Did you damage your heads?

Dutch Scooby lover 03 December 2011 05:00 PM

The head swap will not work 100% perfectly.
The piston tops and combustion chambers are different between v4 and v5, which leads to (and I always get this wrong) a V4 engine with v5 heads to have a higher (or lower) compression and wrong squish.A V5 engine with v4 heads will have the opposite.

So simply put, f you want to have the car be 100% get the correct head and engine combo.Just mixing and matching is not ideal (but could be made working with modifications to the heads/deck/gaskets)

joz8968 03 December 2011 05:20 PM

Yeah, if the CR is too high, then you can simply fit the correct thickness i.e. thicker HGs.

If the CR ends up being too low, then the heads' or block's mating face can be skimmed to the correct height.

Best to speak to David at API - he'll set you straight. He might even have a suitable block, or indeed a full STi 5 or 6 motor available...

Dutch Scooby lover 03 December 2011 05:32 PM

But with the thicker gasket/skimming method only the CR gets corrected, the squish is still not ideal, and thicker gaskets for example can cause fitment issues for timing belt covers (and thicker gaskets seem weaker to me, tho that is just my own feeling, not something I measured)

joz8968 03 December 2011 06:00 PM

All fair points, DSl.


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