27 replies to this topic

[blackoctagon]

Arno,
I remember - I was one of them.

And, I agree the 52mm 'upgrade' made it worse on cars without re-calibration. The MEMS1.9 and 2J were awkward to re-work.

You can read about my adventures with all manner of MG Rover k-series here: here: https://www.mg-rover.../search/112994/
I wrote tons about them and still get an email inbox full of them every month.

I even made a 50mm throttle body once - https://www.mg-rover...1/#post-5053582


I still build k-series. It's a good engine, but even I can't deny it had its troubles in early production, and the dealer and customer service denials just made it look worse.
It makes a great teaching case study, and lots of engines that came after it took lessons from it.

[Arno]

Yeah.. The Rover K is a classic example IMHO of an engine that suffered the most damage from bad manufacturing tolerances and cover-up or denial reaction from the manufacturer and not so much a basic problem in the engine itself.

 

It's design was quite clever, new and light, but it's just that cost-cutting measures (plastic dowels.. sigh..) and inconsistent production efforts (esp. varying liner heights) combined with less than stellar finishing of parts was something this fairly revolutionary 'sandwich' design with the long bolts just could not tolerate and the results are well known with blowing headgaskets..

 

Combine that with pushing the limits of the engine envelope as it grew from it's original 1.1 to a 1.8 in the same block and it was unfortunately a disaster waiting to happen.

 

The choice of a heat-sensitive/annealing aluminium alloy for the head was also not that great combined with the original thermostat setup.

 

These days, most K's (re)built properly and with attention to the various parts, are quite reliable even to pretty high power levels. Pity Rover never managed that.. (and now the N-series parts supply like headgaskets seems to be suffering from counterfeits in the official parts delivered from the new chinese owners..)

 

Bye, Arno.

[TFD]

Not weight, but size..

The 65mm le5 is wider then the 58mm oem tb.
This is an issue when using the saab intake manifold en tmap. 65mm tb gets in the way of the tmap.

But thats more for the turbo guys I guess.
Leaves me with a 65mm tb...

[smiley]

Leaves me with a 65mm tb...

 

That is plenty to drive it around the church like you do.

 

[TFD]

Drivin in general would be a bonus right now lol...

[oakmere]

When I had issues with the ported 58mmTB is was the car going into limp mode as the ECU thought there was a fault. I had no drivability issues.
CS we’re seeing approximately 5-7 bhp gain from the 65mm TB on a CS5 level of tune. They could never get the mapping right though at low load giving the EML issue.

[blackoctagon]

My own current modified 58mm has never given me any problems like that. I can't say anything to that other than sorry to hear you had the issue.

I don't know what a CourtneySport5 level of tune implies but, and I don't want to besmirch them here, it sounds like they changed something and didn't compensate for it (or a related thing) elsewhere.
If that was the case then I can sympathise - reading the tables in the GMPT15 is a pain. It's taken me ages just to get to the point where I can remove the EGR, change the idle and warmup curve - that dual range coolant sensor calibration was a pain - and adjust the fuel tables.

[oakmere]

Keep porting and you will get issues. Mine was pretty much maxed out without touching the idle control area.
Klansen did the mapping work for CS but could never fully crack the ECU.