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Bullet-proof K-series? SAIC Kavachi?
gasket999 - 25/10/22 at 05:39 PM

I've owned a few cars with (Rover) K-Series engines over the years and have always liked the engine performance. Growing up in the 90s, it was often fitted to many of the more interesting specialist cars too and I've always considered it to be a bit of an unsung icon - with impressive engineering, weight and size.

However, when building cars I've never actually chosen to fit a K-series due to the reliability issues, primarily around the head gasket. I once had a daily-driver with a 1.8 fitted (a Freelander of all things) with the revised head gasket... it never let me down but always felt like it was a ticking time bomb.

Now I'm late to the party but recently learned that when Shanghai Automotive bought the MG brand, they commissioned Ricardo to make fix all the reliability issues, which they did and ended up with (according to Wikipedia at least) a very reliable unit with no reported head gasket issues.

Now these revised 1.8 K series engines (rechristened the Kavachi engine or the TCI-Tech) are easy to find second hand - either in naturally aspirated 131bhp or turbo'd at 158BHP for around the £350/£400 mark. Equally, the parts supply from Shanghai Automotive is also pretty good with brand new blocks and other parts available for around £450.

I've anecdotally heard that the parts are backward-compatable with Rover Ks too. Again according to Wikipedia, SAIC gave the engine "a redesigned head, improved waterways, stiffened block as well as changing the manufacturing process and quality of materials".

So I was wondering if anyone on the forum had experience with these revisions as I have a new project starting (mk1 Elise resto) and would like to bench-build an engine for it before I start to strip the vehicle down. I'd ideally like to build a recipe for a 1.8 Rover K built using select SAIC Kavachi parts and wonder if its possible to build an incredibly tough little engine that delivers on the original K-series promise.

The turbo option is really interesting too - less for the actual turbo itself and more for the (presumably upgraded) bottom end for a real belt-and-braces build... or maybe a supercharger.

I'd ideally like to have as many Rover parts as possible, only changing those bits that had been improved by SAIC/Ricardo.

[Edited on 25/10/22 by gasket999]


djtom - 26/10/22 at 02:22 PM

Certainly the block is compatible, according to 30 secs on Google that turned up this thread on a Caterham forum...

https://www.caterhamlotus7.club/forum/techtalk/just-because-i- can-k-series-content

Would be interested to hear whether there is a benefit in using the head - although I suspect the hot K Series fettlers like DVAndrews would have been all over it by now if there was.


russbost - 27/10/22 at 08:14 AM

Interesting to hear there is now a proper fix for the head gasket issues, but what is the advantage to going thro' all the work, parts acquisition & potential incompatibilities to built a part new, part old K series? Why not just buy (& rebuild if necessary) one of the newer units & use it as a piece rather than finish up with a "frankenengine" - I'm not seeing what the gain is?


rdodger - 27/10/22 at 08:52 AM

My understanding the block is compatible the head not as it is taller with different cams.

The main issue with the K series was the dowels were plastic originally so softened allowing the head to move about causing HGF. They also suffered thermal shock in mid engined cars as the thermostat as standard is on the back/return of the engine.

Steel dowels, uprated head gasket, later Freelander oil ladder, liners set to the correct height and PRT or remote thermostat and it should be very happy.


crimondbanger - 27/10/22 at 06:11 PM

I've skimmed a few rover heads and they all pretty much fail because of the poor "cheese" alloy used for the head casting. The head gaskets used to sink in to the heads causing the failure.

If you take an old valve and tap it around the gasket landing on the head to compress it and then skim . Easy job and seamed to fix them for good , could have the car in and out the garage in a lazy morning ( i have a milling machine which helped as I would skim them without stripping them down ) . Never understood why they got such a slating as its a great engine and the quotes some folk got for repair was just ridiculous considering how easy it was to fix.