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Discussion Starter #1
It seems that MGR have a good line up of engines, but ZS and ZT need more power. I know the Ford V8 is on the way, but knowing MGR they will soon get the ars3 buying these engines and will want to create their own masterpiece ; - ))

I think the KV6 is a great engine, but it has it's limitations . . . .

It has a very heavy flywheel which means it will never have an electric response like the old Ronda 2.7's in 800.

When MGR put it on the tuning benches for ZT they were hoping to hit "The magic 200BHP."

I guess this would have given marketing benefits for MGR as well as giving more performance to punters. They managed 190, but were short of their own target BHP.

I guess the problem may be the same inherent problem as with the four bangers - Cylinder head and specifically porting.

If you look on the net, some of the Elise boys have been very busy with the 4 pot K's and in 1.8 form they conclude that the problem to getting increased power is engine breathing.

Once this is addressed spending ££££'s they are able to get close to 200BHP from 1.8's!!!!! Hello Honda VTEC!!!

The 4 pot K was initially designed as a small capacity engine, therefore valve sizes and head porting sizes are for the air flow of a 1.4 say. The KV6 was developed on a tight budget from effectively bolting 2 four pot K's together and shaving 2 cylinders off the end (as with the "once a V8" Metro 6R4 lump)

Having driven both 1.4's and 1.8's in anger, I would say this breathing problem is evident.

The 1.4 is very revvy and the higher the revs go, the more pull you get. The 1.8 (non VVC) feels different and whilst it is in a class above anything ford and vauxhall churn out in terms of power delivery and revability it does not feel as urgent as the 1.4's at high RPM's.

This would explain why the VVC was developed, effectively addressing this breathing problem by keeping the inlet valves open for longer and allowing the engine to take a deeper breath. Without the need for massive development and tooling changes to actually alter the basic head design.

All this means that even if MGR developed a 2.7L KV6 (each cylinder 450cc as the 1.8K) they would encouter these breathing issues.

They have several options then:

A 2.7L or above KV6 equipped with VVC on the inlet cam on both banks. - Would maybe give over 220BHP.

A KV8. Mentioned by some on the forum already. The KV8 would then be around 3.6L capacity, without VVC and would breathe on the limit like the non VVC 1.8's.

Thoughts anyone????

Matt.
 

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There are people on this board far more able to comment on the actual possibilities for future development of the K than me, but the modular construction of the K was designed to yield V8 configurations, and some were certainly made (3 guesses who put a stop to all that) and ran in a few 800 mules around Longbridge. I dont know if this route is being actively persued at this point, depending on intellectual copyright issues/future planning for petrol engine development.
 

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Remember the Stag?

I hope that if the guys at MGR do get round to a KV8, they try a bit harder than Triumph did! They also built a V8 from two four-cylinder engines, creating one of the world's most unreliable engines. Tragic, really.
 

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I spoke to a Stag owner not long ago and he told me that his had done over 150K without any problems, so perhaps it was a quality problem rather than design, and as todays MGR cars are superbly built, that shouldn't be a problem.
 

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Stag V8

In fairness, the Triumph V8 was a decent engine when it ran, but it was very sensitive to maintenance. Modern oils help a lot. At the time, though, people expected it to have the same bullet-proof qualities as the Rover V8, rather than needing constant TLC to avoid expensive and usually terminal failures. That's why so many Stags have been retro-fitted with Rover V8s and Ford V6s.
 

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We should remember this was the 70's, the Red Robbo years, when Saab made the Triumph 4 engine they didn't have the problems of the Triumph built ones, I think Saab kept the basic design for many many years.
 
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