Russell Jupp

New Member
Hi all, now having got my 1.8 petrol FL running as it should, its time to play with the intake and exhaust sytems to make it really fun. Now, i think I'm right in saying that this motor makes around 115 bhp? My 51 plate MGZS makes 130bhp.
My questions are:
1. where are the differences? ECU? throttle body?
2.What after market mods are available that actually make a difference? de-cat pipe?
K&N filter instead of the original, horrible filter box and pipes?
any help would be really appreciated!!
Thanks in advance, Russ
 
The ECU isn't re-writable, you'd need a third party ECU replacement.

There are many types of camshafts available for the K. PTP have many on their site, but some of them require other modifications also.

For best (cheap) gains, get yourself a conical K&N and rip out the airbox, putting the K&N right on the throttle body (this is how they are in some Caterhams, no airbox or pipes in between throttle body and filter). De-cat pipe would be illegal in the UK as it's a petrol, but get yourself a nice stainless steel all the way from the headers and you'll get rid of the restrictive bent corners etc from the old mild steel exhaust.

Also, get the 52mm alloy throttle body, a lot more responsive than the stock 42mm plastic.
 
Thanks Crewe Biker, now, it would seem to me that the FL motor has more torque than the ZS motor, but i suppose it could be the gear ratios? Will try the bigger throttle body, and K+N filter, but leave the cams for now. Do you have any info on ecu units ie what to look for? Thanks, Russ
 
Emerald apparently make some of the best ECU's for the K series. I've heard of others but can't remember the names right now.

Quite of bit of info on the K series: K series engine tuning page

The throttle bodies can be picked up on PTP's site for about £140 i think. There are some 56mm throttle bodies on ebay but i wouldn't touch them as too big a throttle body could mean a loss. You'd probably need a lot of porting work to benefit from a 54mm or a 56mm.

The alloy throttle body also replaces the issue of 'sticking' that was sometimes found in the plastic ones i believe.

The throttle body and air filter mod are well worth the money on their own in my honest opinion.
 
Emeralds are expensive something like £700 and you only get 7% power gain (aspirated engines), IIRC, it does allow the user to tinker online, useful for track days

Better to gas flow the head, rough casting just needs smoothed out,

Valve porting can also be done (machined cutter only) with bigger valve seats.

For straight swaps, a deCAT, early 1.8's with dizzy cap are plug and play, removes any flat spots in the power curve.

The newer 1.8's (MEMS 3, twin coil packs) have a 2nd lambda sensor after the CAT, apparently needs an MIL elliminator plugged in to fool the 2nd sensor.

52mm TB are as high as you should go on a k-series, larger inductions slows the air, unless like crewey you have an air scoop giving ram air ;)

I'm not a fan of K&N due to heat soak, some peeps use the air filter housing from a Rover 820 to enclose the filter.

I have a panel ITG (cut from a RR vogue)

If I had £200 to spare, a VADER kit would be on the cards, vader by name Darth Vader by nature

welcome to the darkside!
 
I was hoping you'd be along sooner or later on this thread N.I. Always the best advice i.m.o.

Say... now i'm in Ireland and i don't have to bother with so many legalities, would you reckon i'd get many gains out of removing the cat? Maybe replacing it with a straight through pipe? And also, what about the middle silencer? I've got a nice stainless steel magnaflow on the back atm so was wondering about a straight pipe totally getting rid of the middle silencer and cat?
 
I was hoping you'd be along sooner or later on this thread N.I. Always the best advice i.m.o.

Say... now i'm in Ireland and i don't have to bother with so many legalities, would you reckon i'd get many gains out of removing the cat? Maybe replacing it with a straight through pipe? And also, what about the middle silencer? I've got a nice stainless steel magnaflow on the back atm so was wondering about a straight pipe totally getting rid of the middle silencer and cat?


You'll need to switch the CAT back for the MOT, I wouldn't have thought roadside checks were a common thing in ROI,

Some k-series on UK mainland have passed emissions without a CAT ???? although I would doubt the calibration of testing equipment in private garages, CAT will lower CO levels to approx 10% of engine output.

the Rover crowd claim that a deCAT on a VVC engine doesn't give enough back pressure, I beg to differ, esp when OEM backbox is used, no rolling road figures for this, purely seat of the pants.

There have been rolling road figures to disprove the back pressure theory within the Rover community itself, but as always never enough evidence gathered for a definitive outcome.
I believe aftermarket backboxes are specifically tuned for the power/sound wave with a CAT in place, so when a deCAT is fitted to a big backbox, tuning is changed.

There are race tuners on other MG forums that talk power equations for a living (one of them is a woman)

A deCAT shouldn't affect fuel consumption, but depends how you drive ;)

A deCAT and OEM backbox on the FL is a bit raspy, but no reason why a garage couldn't build you a ss system. Plus you'll pay for ss, not significant enough power gains for the money IMHO but looks the part ;)
 
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Thanks for your info everyone. Its obviously not a high performance racing car, so I will be sticking with simple, cheaper mods that make it just a bit more fun to drive!! I'm interested in your thoughts on air filter systems, and understand about 'heat soak'. I have seen on ebay, a carbon fibre cylindrical shaped filter box, with a filter enclosed, and a length of flexi-hose that is suppose to alleviate this problem? Also has anyone ever thought about an MGF back box, adapted to fit a FL? Would look very cool if done properly!!
 
I've not seen a MGF airbox before but i don't have too much of a problem with heat soak (as i've got cold air being fed through my scoop into the filter) but thinking about it, some of the K 1.6 caterhams had conical ITG's if i remember rightly and these were right on the throttle body, without any heat sheilding and with the position of the rover engines in the caterhams, the filters were quite near the back of the bay, where the air is usually at it's hottest.

You can get stainless steel shields to cover the K's exhaust headers and also i think wrapping the headers in exhaust wrap would probably get rid of a bit of heat out of the engine bay.

For some reason i'm not too keen on the shielded type filters, or air boxes at all (not sure why, just don't appeal to me).
 
Oh, and cheers for the info on deCatting N.I....

I saw a decat pipe on ebay for the 1.8 a few days ago so may experiment with that before replacing the whole piping with SS.
 
Sorry Crewey, meant MGF back exhaust box, to replace standard FL back box. Would look very ineresting if done properly!!
Russ
 
Ah yep, my fault... you did put back box. I must have been reading it too quick! Certainly would be interesting. Is the MGF box one that sits across the back?

One reason i replaced mine was to get it out of harms way when i take it off roading sometimes but i feel it gives a smoother flow to the old exhaust. The old exhaust was only mild steel and the bends had not been mandrell bent (the bends weren't round, kinda squashed) so i replaced everything from the cat with SS mandrell bent piping.

http://www.landyzone.co.uk/lz/f9/new-back-box-74668.html

My post is a bit further down on that page.
 
It's meant to save the IRD just incase your VCU seizes. I'd prefer to get a new VCU/IRD rather than have a half capable freelander though. Although many people don't take em in the mud.

I've heard if you do occasionally take it in the mud and get all wheels spinning it'll help stop your VCU seizing? Possibly from getting occasional use out of it?
 
Crewey, the box itself sits across the back (in much the same way as FL) but I'm guessing that the angles and lengths would be completely different, but I recon my local garage could adapt it to fit, but like I said it would need to be done properly, or it could end up looking like a big boy racer Saxo or similar!!
 
Lol...i heard (on here somewhere) that if you get them wet, the doors fall orft...or other similar, hideous thing will happen...I bought it as my 'winter' car, not really intending to go off road, other than take the dogs and kids to the moors!! So 2wd suits me fine...also really woried about possible IRD failure, so took garage 's advice, and off she came.
 
I'm familiar with the MGF backbox, the back bumper would have to be cut so tailpipes exit properly, problem is the mid section that twists up and over the subframe of the FL. Again no reason why a good aftermarket couldn't fabricate a ss mid section to suit.

Crewey - K&N's suffer heatsoak more as they are made from cotton type material.
Ducts dont look as cool but if you get ram air from a duct/scoop pointed forward, the faster you go the faster the air inducted..
You could make one from a plant pot!

8 in a V - prop off does make a difference, but oh the looks on peeps faces when you bury the throttle on a 'tweaked' FL.
Have you ever remapped a MEMS3 (new coil pack) using your testbook? It can be done.
 

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