4-2-1

[sootysteve]

thinking of getting one of these.... is it worth it? at £600.00 what are the benefits?

[spike]

i had one fitted when my down pipe went... definatly more low end 'grunt'. i had a crp fitted at the same time - i think you know how it sounds!!

mines a janspeed btw

[Joff135]

I had a smallbore Janspeed 4-2-1 fitted a few months ago...i was told that my original flexi may have broken at the time as there was an annoying resonance at 2000 rpm...although when it was taken off it looked OK?

 

I am very pleased with the 4-2-1...deeper tone to the exhaust sound...feels and sounds more free flowing...and when you see what it replaces you know why it has to be better! Definitely more mid-range torque too.

 

A chap on SELOC has done back to back tests on the original flexi system against the 4-2-1 system...and BHP at full blat was not actually any different on a standardish Elise...but it is the extra torque that you get mid-range that is important. Apparantly really really suped up Elises' do gain some BHP from a 4-2-1?

Mine cost me £500 including fitting...but the Lamda sensor broke on removal as it was well rusted in and cost me another £75 for a new one.

 

Would i recommend doing the mod?...yes if you will be doing trackdays (which i don't)...but if your car is just for lovely weekend drives then perhaps you can live without it? Don't get me wrong...it is a definite improvement over the original..but if that is not broken then do you really want to spend £600?

A de-cat pipe will give you more noise and if a non-VVC engine a bit more BHP too...about an extra 3 for what it is worth anyway!

 

If you have the money available and don't mind spending it then buy a 4-2-1...but when you sell the car no-one will give you any extra money for it...and it is a 3 hour job to fit it...so i certainly won't be paying someone to re-fit my original when i sell my car.

 

If you fit one and your car is under 190 BHP...you need the smallbore versions...speak to Simon at ptp-ltd.co.uk about that...such as Janspeed or Piper. The big bore versions are too big for standardish Elises and you lose power apparantly!

[Steve J]

Was under the impression that a 4-2-1 gives better mid range and a 4-1 gives more at the top.

[sootysteve]

thanks for the advice, the car is a std s1 i already have the elise parts exhaust, and crp but found it too loud as i use the car daily, hence the cat is now back on n still happy with the noise, i dont do track days, the 4-2-1 was looking at getting is also elise parts, but its big bore, (had no idea may lose power with it)

 

i get the horrible buzzing noise abit at around 2000-2500rpm does my head in! the original down pipe looks ok, but a reliable source told me that they do go at the flexy bit.

 

will have to look into the big bore loss of power thing b4 i buy it then. did want the elise parts one though as they are so well made, look like they should be in an orchestra!

[Steve J]

There's a better one that the Elise Parts manifold. Think Steve Butts provides them, and they're cheaper too. Main problem is fitment AFAIK. Try a search as this has been discussed before or give Scott Mac a PM.

[strees]

I have the piper 4-2-1 from Steve Butts. £420 all in, plus the fitting (horizion did mine). Very neat installation, easier than the janspeed (i was told), and very nice improvement across the range (torque rather than bhp). Noise is also increased

[Joff135]

S1 160 Sport actually has the bigbore 4-2-1 which the Exige has...which means that it has the wrong one fitted for optimum performance results.

[Rus]

The piper 4-2-1 that Steve Butts sells is probably the one i'd go for. It has a flexi section, so the engine steady bar shouldn't be needed. The solid ones, as pictured, sometimes need them to prevent the manifold breaking or the manifold gasket from failing. The piper one also fits past the oil filter if you have an oil cooler sandwich plate fitted, whereas with the janspeed a smaller filter needs to be used(from the renault 5 turbo i think).

 

Rus

[Scott_Mac]

I had the Janspeed one fitted about 18 months ago, and it's a great mod... lots of lovely torque

 

It's not cheap but it's a great mod... the Piper one is supposed to be very good, but i've not driven a like for like car with it fitted so can't comment on differences!

[MilesH]

Picked up this old (ish) thread after looking into 4-2-1's. From reading there seems to be 2 types of 4-2-1's offered, a flexi and a solid, with the flexi not offering as much of a gain as the solid, whereas the solid can have vibration effects and increased wear on parts.

 

Is this the case? and is there a general concensus on which to go for?

[GCCK]

Avoiding the technicalities, the need for a flexi section along the length compromises the potential length of the primary pipes. Ideally the longer primaries will lead to further (though smaller) improvements in torque and power.

 

Downside of a solid system is that you need a stiffer bottom engine mount to reduce the inherent rocking as you go on / off the accelerator, otherwise over time you will cause metal fatigue in the manifold, leading to breakage.

 

I'd say on a standard car, you'd be better off with a flexible system, ideally smaller bore to maximise torque. A std car won't have the throughput to benefit from top end power of a solid big bore (all the solid models are big bore).

 

I was getting 170+ bhp on a std manifold before it broke, and went for the Janspeed small bore with flexi, because I live in Hinckley and the car was driveable without exhaust the 2 miles to PTP who are main Janspeed distributor. Even at the top end of power outputs for small bore, I'm very happy with both top end power and low end torque that has resulted.

 

I also had the adjustable / stiffer engine bottom mount (from Eliseparts) fitted. Don't do it for the sake of it (and you don't need it if sticking with a flexi manifold). Whilst it reduces "shunt", which was my reason for the change, there's no doubt it introduces extra vibration just above idle speed, so for day to day, the loss of refinement would annoy.

[AL G]

My flexi went last week - I'm gutted as I can't afford a new manifold (have ordered the toe link upgrade and a holiday to pay for this month, oh and insurance on the 18th - shit forgot about that one)

 

I just went for a new Janspeed flexi section, 4 new exhaust mounts, new gasket to manifold, new gaskets either side of CAT, nice new stainless nuts and bolts all round.

 

It cost me £138 for ALL of this lot, delivered (PTP, and Rover parts direct).

 

I'd have gone for the Piper from Steve Butts - seems like a niec bloke, I'm regretting my decision already. Even though my manifold is fine (for now) it'a a no brainer

[MilesH]

Avoiding the technicalities, the need for a flexi section along the length compromises the potential length of the primary pipes. Ideally the longer primaries will lead to further (though smaller) improvements in torque and power.

 

Downside of a solid system is that you need a stiffer bottom engine mount to reduce the inherent rocking as you go on / off the accelerator, otherwise over time you will cause metal fatigue in the manifold, leading to breakage.

 

I'd say on a standard car, you'd be better off with a flexible system, ideally smaller bore to maximise torque. A std car won't have the throughput to benefit from top end power of a solid big bore (all the solid models are big bore).

 

I was getting 170+ bhp on a std manifold before it broke, and went for the Janspeed small bore with flexi, because I live in Hinckley and the car was driveable without exhaust the 2 miles to PTP who are main Janspeed distributor. Even at the top end of power outputs for small bore, I'm very happy with both top end power and low end torque that has resulted.

 

I also had the adjustable / stiffer engine bottom mount (from Eliseparts) fitted. Don't do it for the sake of it (and you don't need it if sticking with a flexi manifold). Whilst it reduces "shunt", which was my reason for the change, there's no doubt it introduces extra vibration just above idle speed, so for day to day, the loss of refinement would annoy.

 

Thanks for the info Graham. much appreciated

 

Looks like it makes more sense to go for the flexi then. Is there any inherent differences between the janspeed and the piper, would make sense to go for janspeed as PTP are closer. Seloc seem to rave about the piper but I assume that's because steveb stocks them?

[GCCK]

Both pretty much of a muchness. Let's face it, most of the engine is still standard.

 

As you say, PTP are closer, have them in stock rather than bought in on demand, do a supply & fit and you'll get the MLOC discount on labour. Mention my name to Richard (sales) or Nick (workshop manager), too.