5 Cylinder VW/Audi engines SOHC to DOHC worth it?

Hello

This is my first post. not sure if this is correct place to post.

I have a 1986 VW Passat rocking the 2.2 KV 5 cylinder engine. It has a standalone EFI Management already running off the distributor. The issue is it has a SOHC 10V and i dont think its very "performancy" if i could say that. i didnt like it in the beginning, but it grew on me and now its a very nice car that is my preferred ride

From my research i have read that one can bolt on the head from a 7A 3B or AAN engine? The problem is that i cant find any and if i do find one it costs more than the value of the car.

Would a $2000 head (more than car market value) justify the gains and wouldnt it be cheaper to make a billet head?

Im aiming for 450wkw result. Does one need a DOHC for that or can modding the existing head be better?

From what i can tell the engine is a (very) detuned version of the Audi Quattro rally car which i think made about 800whp.

Thanks in advance

Not an engine I've any experience with, but I think you may be best to forget all about a "billet" head as they are very expensive (especially if designing from scratch) and are normally a drag-only item without water cooling passages.

With the 20V head, I expect you're also going to have to look at pistons* to match the valve pockets, have a different intake and exhaust manifold, and have numerous other problems.

What may be the best option is a correctly ported 10V head with new, oversize valves - that way you've have an "as new" head that matched what you already have, which will allow progressive improvement rather than an "all in" budget killer for the 20V.

*You're probably going to have to look at those, anyway, with rods, for the 10V, so may not be such a significant issue - if you can get them.

thanks for the reply

yea i can get rod from the RS2 and pistons from the same car.

specs on my car

https://www.carfolio.com/volkswagen-passat-cli-21010

the rods im looking at

https://www.k1technologies.com/products/043DP14144

pistons im looking at

https://www.cnc-motorsports.com/ke222m82-wiseco-audi-rs2-2-2l-forged-pistons-3-228-bore-82mm-7-2-1.html

then im going to balance all reciprocating mass custom intakes and manifold also slap on a small/med turbo and add teh All Wheel Drive gearbox and diff then im done

the head is the part that holds me back but adding bigger valves might help i didnt think of that.

here is a forum link that just can be scanned through just to get an idea of the "look" of the head and engine

http://schorsch9999.forumprofi.de/t1524f21-V-Tuning-bei-einem-KV-Motor-3.html

ill look into getting the cam reprofiled and valve size increased. that makes more sense

EDIT: teh pistons of above are for the 20V head i have not found decent pistons for a KV 10v yet

Had a bit of a lookie, but didn't find much, probably because I'm not familiar with VAG engines and they seem to change them every couple of years.

With most manufacturers they may use the same cylinder head/valve/chamber design over several different engines - this means you may be able to match pistons with a different engine within the VAG family. I'd look at bore diameter, valve pockets, nominal compression, gudgeon/piston/wrist pin height and diameter - with the latter two, it isn't a significant problem as, if required, you can get custom rods made.

Failing that, or in parallel, I'd suggest contacting the manufacturers directly as you may be able to have some custom machined 'one of' blanks, if they have the data, as they generally list their current designs and possible not their NLA designs.

Just swap in a turbo engine from a 400 quattro, it'll drop in and give you what you're looking for.