1.4 - 1.8 upgrade, adding to the existing learning

[Pelico]

The 1.4 – 1.8 K series engine swop is well documented in techtalk. Having completed the exercise at the weekend we learnt a few things and encountered some new snags. I have had emails to the effect that a few more are still thinking about this swap so I thought I would document the new stuff to add to the collective wisdom.

 

The starting point was a 1.8 engine block from an MGF already married to a Caterham Supersport head that had been DVA ported. We needed to swap all my ancillaries from my across 1.4 Supersport engine, including the sump and pick-up pipe. And install a new 3 bar FPR, fuel rail and cream injectors onto my existing inlet arrangement.

 

 

‘New’ Problems

-------------------------

 

1. Sump

 

We surprised to discover that the crank ladder of the new engine did not have any holes to attach the two bolts that hold the pick-up pipe. We manufactured an attachment for the pickup pipe to the baffle plate using a nut, with one flat cut down with a dremell to fit around one of the castings, and a short bolt and lots of thread lock.

 

We then discovered that the pick-up pipe was too deep to allow the sump to attach. So we dismantled the pick-up pipe attachment we had just fabricated, modified the pick-up pipe (bent it in a vice !!!) and re-made the attachment.

 

At this point I decided I did not want to have to mess with this every oil change so I chose to go without baffle foam, and did the DVA ‘two holes in the sump gasket’ mod.

 

2. Alternator belt

 

The crank pulley on the new engine did not match the pulley on the alternator. We swapped the crank pulley from my old engine annoyingly 2 alternator belts sourced from Rover and another one supposedly matched to my old belt, using some sort of measuring gauge at Halfords, were all too long. We reused the old belt.

 

3. Plenum fouling the FPR.

 

After the first start we had a massive fuel leak from my new FPR (FPU, rail and injectors bought off ebay and fitted to my existing inlet). We worked out that this was my forward facing alloy plenum fouling the new FPR which was different shape to my old one. This little touch was enough to compromise the o-rings in the FPR and cause a leak. This needed a removal of the plenum from the manifold and a little bit of work with a file on the edge of the casting.

 

4. Idle troubles.

 

Still had not time to run the engine much but we had problems getting a tickover without stalling. For the moment we have simply turned the idle adjuster screw under the throttle cable crescent one turn.

 

Expected problems

---------------------------

 

We expected to need to drill the M6 sump mounting holes to accommodate the M8 fixings on the new engine. This was surprisingly straight forward. A bench drill with a tilting table helped as the longest drilling (60mm) needed was at and angle (15deg IIRC)

 

There was a difference in depth of the spigot bearing in the crank of 5mm between new and old engines, but fortunately my 6 speed gearbox fitted without the well documented input shaft modification.

 

Some nuisances

-----------------------------

 

Just about every part I bought from the Rover dealer was useless. Sump bolts were wrong, alternator belt did not fit and the inlet manifold gasket was different. I would suggest source everything from Caterham parts !!!!

 

A fixing on one engine was not the same on the next; a good example was the throttle support bracket. We spent lots of time with the tap and die set, and discovered lots of strange threads that were only solved with mysterious bolts from Steve’s magic assorted nut and bolt box.

 

We planned 11 hours. It took nearer 21 !!!!

 

Oh and above where I say "we" in reference to solving the problems……I probably really mean Steve, Duncan, Neil and Richard…….I stood round constrictively panicking. *eek* 😬

 

[Allen Payne]

I must have been very lucky when I did the same conversion last year as everything just bolted onto the new MG block in the same way as the 1400 block and only took a day to install it and get it running

 

I didn't see the issues with sump, but then mine is dry sumped.

 

The engine idles fine, but did require the ECU to the re-set.

 

Out of curiosity why did you change the FPR?

 

[shn7]

Peter,

 

Allen's idea of an ECU reset might be worth a try re the idle problem. Not sure from memory whether the MEMS learns about fuelling. Anyone else know?

 

Steve.

[Allen Payne]

I don't thnk it learns about fuelling, but about the start/stop points on the thottle pot

[Tony Whitley]

I didn't have any trouble with my (ex-Elise. EU3 replacing EU2) engine either. I solved the alternator belt problem by measuring the old one (too long) against all the ones in Halfords.

using some sort of measuring gauge at Halfords

That's quality engineering, that is. I did it by eye Mine is HB737e but that's probably not much help.

 

It did take me an age to track down bad idling and general poor running - I'd belted the TPS and broken the +V connection.

 

I didn't have to change the sump mounting holes either. The input shaft modification was pretty straightforward though it was "measure 8 times, cut once"

 

"constrictively panicking" is that a medical description of your sphincter?

 

Edited by - Tony Whitley on 17 Jan 2006 19:52:24

[Pelico]

Yes I will try an ECU reset.....roll on the weekend ! 😬

 

Allen, I changed the FPU based on the general advice here. Although I know some have stayed with the orginal with no problems. The move to a 3 bar one to match the cream injectors was all part of the same donor fuel rail from a rover 416.

 

The 1.4 - 1.8 club is getting bigger and bigger. Should we get Angus to design us a special badge 😬

[SLR No.77]

[DavePalmer]

Peter,

 

I had idling/stalling problems with mine on the overrun. Mine is ported. DVA suggested a nylon plug in the throttle bypass hose with a 3mm diameter hole in it. This along with some fiddling of the throttle stop screw to ensure a supply of air for idling seems to have done the trick .

 

MEMS does learn something as I found mine improved with driving, so definitely try the Mems reset.

 

I do still have problems with some kangarooing when crawling, this is easy to drive around but is on my list of things to address. Mine was a basic 1400, I had 633 (supersport like) cams put in at the same time but am using a bog standard ECU and haven't got verniers. Any of you 1400 -1800 guys had this problem and got a resolution ?

 

 

 

 

 

[Englishmaninwales]

Nah, Tony. More like measure 15 times, cut once.......I'm not sure about "constrictively panicking,'' but more like a good test of ''sphincter tone''

 

Malcolm

[SLR No.77]

install a new 3 bar FPR

Isn't the 1800 FPR nearer 4 bar, the 1400s and 1600s being around 3.3 🤔

 

Stu.

[oilyhands]

The 1800SS is 4 bar and adjustable because it uses the 1600SS ECU, the regular 1800 is 3bar.

 

Oily

[SLR No.77]

Thanks Oily

 

Peter - this may be relevent to your conversion (or not?) ?

 

Stu.

[Englishmaninwales]

I retained the original 1400 FPR and all seems to work fine.....should I be changing it to the 4 bar type

 

Malcolm

[Pelico]

Interesting ! I wonder what my original 1.4ss FPR was ? Its certainly looks very different. The old one was a one piece silvery unit that did not appear to have any labelling. The 'new' one is black two piece with a retaining clip and is labelled 3bar.

 

This thread here seems to suggest that people are using the 3 bar unit up to reasonably high bhp.

 

What would be the symptoms of the fuel pressure being a limiting factor, would overtly it run lean (spark plug colour ? temperature ?), or is it just the power would be lower than it's potential.

[SLR No.77]

Is your engine SS or non-SS?

 

My original 1400SS had an FPR of the same design as the 1800 version, but was marked with a different coloured dab of paint - IIRC the 1400SS was green, the 1800SS is red 🤔 Both fitted perfectly in the same position at the end of the fuel rail, with teh forward facing plenum/TB.

 

Malcolm - I believe the FPR can be "adjusted" by squeezing it in a vice using sockets covering each end - or so I've been told! I seem to recall Peter Cox explaining to me some time ago that he'd rigged up a way of calibrating the FPR whilst squeezing it in a vice - I think using a foot pump with guage? It's a one-way process though 😳

 

Stu.

[shn7]

DVA adjusted my FPR using the vice & socket method. It was an incremental process and tested on the car between each increment. I'm not sure that testing with air would be the same as with fuel though I can't explain why I think that .

 

Steve.

[CHRIS CLARK]

Steve.

That method employed by Dave A sounds awful I know, but is the way that it is done by Caterham!!!!! 😬

Dave's way is much more cost efficient on your pocket too