The MGF Register Forums

Have you done the basics?

4-2-1 works well on 135 but not the 160 eg Piper
Induction kit eg ITG
exhaust eg Daytona
Sports cat

If not do so before the remap

Not sure I'd bother with the sports cat, but the rest of the list that Colin has posted is spot on, and is essentially the spec of my own MGF (bar a DVA quick n' dirty head port!) Makes for a very nice driving car.

colintf wrote:Have you done the basics?

4-2-1 works well on 135 but not the 160 eg Piper
Induction kit eg ITG
exhaust eg Daytona
Sports cat

If not do so before the remap

Thank you added to my to do list on the new 135 and I have just realised thanks to your post I can have a re map

Thanks for everyone's contributions to the thread. I am a bit concerned about getting a Piper 4-2-1 as I've read that the bolts holding it to the engine often shear and that the connective flexible coupling have very short life-spans! Can anyone who has one fitted tell me if they've had any trouble? I do read a lot on the internet, what's true or not leaves my mind-boggling.....lol!

Probably the single mod that gives the best performance gain is the 4-2-1 manifold. It increases bhp of course as the exhaust gasses can flow freerer but the increased torque is wonderful, you really notice that. As for quality, I have the Piper from Mike Satur and it's no problem, it's my second one, the first being on the F and I left it there when I sold it in 2008.

However I trust no other as I know of several examples of buying from other sources where quality and fit was a major issue.

I can't comment on the Pipe 4-2-1 but I have a Janspeed manifold fitted.
Its never sheared and fasteners or had any other issues, but I did have to replace the flexy section last year, after 8 years and around 70K miles of use

Steve White wrote:I can't comment on the Pipe 4-2-1 but I have a Janspeed manifold fitted.
Its never sheared and fasteners or had any other issues, but I did have to replace the flexy section last year, after 8 years and around 70K miles of use

Funniliy enough Janspeed could not get their Janspeed TF Manifold to fit my TF - much to their embarresment a few years ago

Interesting replies. Encouraging to hear that it went after 8 years, must sell mine before then! Lol ! The issues I read about Colin were all around the Janspeed 4-2-1, so I will be opting for the Piper me thinks. Valuable feedback peeps, much appreciated......

The one that would not fit my TF was a Janspeed unit. None of the holes lined up to the studs and there were no heat shields to go with it. Terrible job trying to get my money back too from the seller.

Ah, sorry to hear that Adrian. Odd that Janspeed didn't get it right, they're not a small company and fairly high profile. Piper here we come!

Putting your old VVC exhaust cam in the 135 as an exhaust cam wouldn't work becuase it'll be missing the cam phase sensor lobe. Running a hotter cam on the inlet side would be a good idea IMO as it should make for a torquier engine.

The offset dowels could also be used, but they'd be best fitted after measuring the existing timing of the cams to see how far away from optimum they are (fitting the dowels could make it worse!)

If it were my car, I'd be swapping the engine for a 160!

Ive taken a 135 to about 142 with just exhaust and induction mods. You could easily take it to 150 with the right bolt ons and remaps, beyond that you're spending silly money for the gain you can get with a 160.

I personally went for new plugs, coil packs and leads first - make the best of stock.Then tighten the throttle cable to as tight as you can get it without it forcing the idle up. When I did that my 03 135 with 50k on the clock made 133 bhp at the fly (estimated).

I then added an enclosed K&N 57i - like on Rob Bells site. 136bhp (same road and same temp range as It was the next day). Then a 10 year old daytona exhaust. Took me to 142bhp.

Lee Pudney has 147bhp with a ZandF remap with those sort of pre-done mods.

The best thing I can recommend buying is an aftermarket manifold. We already have 4-2-1's on the car (people seldom know this) but they are of poor design, even on the TF. A Scorpion 4-2-1 (which was the worst in my opinion) made a massive difference to the feel of my MGF VVC. It would have an even bigger impact on a 135/MPI engine due to power peaking lower. Daily driving was transformed.

Most cost effective power mod is usually a filter on our cars - but the gains are relatively limited on the later cars with its larger air box and dual air intakes - just make sure that these are directed into nice, cold air.

Exhausts broadly make about 5bhp/5 lb.ft for the best ones (the good old Daytona was best, with the Milltek Supersport just behind).

4-2-1 manifolds broadly don't make much extra power but can make oddles of torque lower down the rev range where you most need it, and the best ones can really transform the way the car drives (the Powerspeed one on my car is absolutely brilliant). Most manifolds are optimised for the MPi head and cams; the VVC's requirements are different and this is likely the reason why the "one size fits all" solution fails to work so convincingly on VVC heads!

For MEMS3 users, we saw at our RR day that Mark's Z&F re-tune netted a good, reproducible 5 bhp gain with much improved driveability. I don't think I've ever heard a bad word about this conversion!

Beyond these changes, you start spending ever more money for ever less gain, but you could consider hotter cams - piper's BP270H might be a good choice, and the 633 a more powerful choice. Also think throttle bodies early on: Jenvey offer a bolt-on upgrade. MEMS3 could be re-programmed to run these, and would be worth discussing with Mark, or consider getting an Emerald. Thereafter talk to my old friend, Dave Andrews, regarding a head port and bigger valves - but bear in mind that an exhaust manifold suitable for a lesser engine will no longer be optimal for an engine in a higher state of tune...

Also consider whether the pistons and rods are man enough for a higher rev limit required to get the most from the higher state of tune. But the good news is that you could potentially be looking at 200-220bhp...

How far do you really want to go?

MGFantastica wrote:Ah, sorry to hear that Adrian. Odd that Janspeed didn't get it right, they're not a small company and fairly high profile. Piper here we come!

I didn't buy it from Janspeed but an MGF parts supplier in the Midlands, a place I will never ever vist again.

Might have been a manifold for a ZR160?

Possibly Rob, would the downpipe still have lined up as that was not too far out but the stud holes would not line up.

Yes, I think this is a definite possibility. I test drove the ZR with Janspeed manifolds for an article I wrote for Phil Raby in MG World about 10 years ago - and I have to say that the most impressive of the two cars I drove was the 1.4 litre 105. Both benefited from similar tubular 4-2-1 manifolds (the one on the 160 had larger bores), and predictably I was keen to have one for my MGF. But they told me that it wouldn't fit...

Looking at the Rimmer Bros catalogue, the ZR manifold uses a different part number to those used on MGFs and TFs, but the diagram picture is pretty similar to the MGF manifold... similar but not the same.

Janspeed did make manifolds for F/ TF and were part of the XPower tuning kits

But they couldn't get their TF manifold to fit my TF