[quote=N17VES][quote=blacktoy]piccies of it fitted will be on the way tomorrow. In the meantime:
[/quote]
Pic of my 2bular (2" primaries) to comapre…
[/quote]
Heh, that’s a big fat pipe 
Pete I use a CEL eliminator. No wiring just a long bolt type thing you screw into the decat then screw the O2 sensor into that therefore moving it out of the way of the exhaust flow.
Fixed that for you BRUMMIE BOY!
[quote=aelord][quote=321freeflow][quote=aelord]Not bad at all.
So to be quite clear, this is a Redesign of the one I fitted about a year or so ago?
If so now I need to upgrade mine, how annoying. [/quote]
The std header/manifold is a piece of junk, barely fit for the n/a motor. For an SC install, it’s a serious block on power. When I first had an Exige S on the dyno, it showed 204bhp. I was first to design a header/manifold that would improve the exhaust flow out of the head. 12-15% gains were achieved. With various mods - re-flashes, smaller pulleys, intercoolers, etc etc the power outputs have been climbing steadily.
So, it was time to have another look at the 4-1.
Steve’s install was a good opportunity - same car, same dyno, same day, same operator. Most of the variables removed. I was interested in the CHANGE because that would have been down solely to the header/manifold.
Worked very well, very pleased.
[/quote]
Hi Jim. I’d be interested to know how much difference you think there is between your original 4-1 (as fitted to my car) and the redesigned new one - I need to work out the cost-benefit calculation!
I agree the OEM one is crap. Big improvement when I stuck your manifiold on. [/quote]
I’m in the same boat, got the original 4-1 on mine.
Neil.
[quote=aelord]
Hi Jim. I’d be interested to know how much difference you think there is between your original 4-1 (as fitted to my car) and the redesigned new one - I need to work out the cost-benefit calculation!
I agree the OEM one is crap. Big improvement when I stuck your manifiold on. [/quote]
Well, the original 4-1 was no slouch Adrian - fitted to 100’s of SC installs - regularly/reliably gave up to 20bhp increase. The large-bore version fitted to Nick’s install worked very well too but I wanted to keep the boost pressures of the smaller bore.
This re-design is just an evolution of that one - shorter, lighter, certainly more efficient. I would only recommend changing out your original 4-1 if you’re looking to press on to approach 300bhp. The returns would be optimised with this re-design. Bang-for-buck, a straight swap wouldn’t be that worthwhile. If you have further tuning plans, I guess you could sell the original 4-1 on to an Elise SC owner?
[quote=321freeflow][quote=aelord]
Hi Jim. I’d be interested to know how much difference you think there is between your original 4-1 (as fitted to my car) and the redesigned new one - I need to work out the cost-benefit calculation!
I agree the OEM one is crap. Big improvement when I stuck your manifiold on. [/quote]
Well, the original 4-1 was no slouch Adrian - fitted to 100’s of SC installs - regularly/reliably gave up to 20bhp increase. The large-bore version fitted to Nick’s install worked very well too but I wanted to keep the boost pressures of the smaller bore.
This re-design is just an evolution of that one - shorter, lighter, certainly more efficient. I would only recommend changing out your original 4-1 if you’re looking to press on to approach 300bhp. The returns would be optimised with this re-design. Bang-for-buck, a straight swap wouldn’t be that worthwhile. If you have further tuning plans, I guess you could sell the original 4-1 on to an Elise SC owner? [/quote]
Thanks Jim - that is really honest and helpful, much appreciated.
Jim, i’ve dropped you an email via your website. After reading all of this i’m very keen to get a full system and begin upgrading the OEM “crap”.
It really really is sh1te
You carbon boy, where do you get those from
Lots of lotus tuners sell them. �20’ish and sincs supplied and fitted mine.
Got you, thank you! I’ve had a good few enquiries and I’m working out a discount/deal for the Header + De-Cat/Cat - if anyone else is interested, please drop me an e-mail on the site - cheers.
Have you got a link buddy? I have seen them before as my mate had on on his S2K but just been on elise shop and parts and cannot see the tube type.
Boothy
Sorry mate I’m in France skiing and have such shocking signal that can’t surf the 'net to see which sites sell them. If in doubt just buy one from sincs and get them to post it.
[quote=321freeflow]
The std header/manifold is a piece of junk, barely fit for the n/a motor. [/quote]
Have to disagree with you there Jim… The std exhaust manifold is more than fit for purpose for what it was originally designed for and I have no doubt it had a very large sum of money chucked at its development and is serving in millions of applications worldwide without failure… Ok, so it was never designed to do what your now asking from it, but to say it’s ‘junk’ is not fair or accurate.
Me personally, im actually quite amazed that the std 190hp 2zz lump and ancillaries can be upgraded with simple bolt on bits and put out 270hp at the flywheel - Still using the std manifold… Cant be all that bad!
[quote=321freeflow][quote=N17VES][quote=blacktoy]piccies of it fitted will be on the way tomorrow. In the meantime:
[/quote]
Pic of my 2bular (2" primaries) to comapre…
[/quote]
Heh, that’s a big fat pipe [/quote]
Size matters
With the Katana using the same Eaton MP42 charger, I do wonder if the katana inlet manifold (Greddy supplied) is better than the OEM Exige S one with results like that…
Katana is MP62 
I actually think the inlet manifold can be improved, there was some research done on monkeytuner a while back where they saw 20whp gains on an NA car.
[quote=TarmacTerrorist][quote=321freeflow]
The std header/manifold is a piece of junk, barely fit for the n/a motor. [/quote]
Have to disagree with you there Jim… The std exhaust manifold is more than fit for purpose for what it was originally designed for and I have no doubt it had a very large sum of money chucked at its development and is serving in millions of applications worldwide without failure… Ok, so it was never designed to do what your now asking from it, but to say it’s ‘junk’ is not fair or accurate.
Me personally, im actually quite amazed that the std 190hp 2zz lump and ancillaries can be upgraded with simple bolt on bits and put out 270hp at the flywheel - Still using the std manifold… Cant be all that bad! [/quote]
Well, you’re entitled to your opinion of course. The std manifold may well be fit for purpose on a shopping trolley Corolla - not on a mid-engined sports car generating the cornering forces of the Elise/Exige - the flexible join at the manifold/cat is poor IMO. It has failed on plenty of occasions. The first Lambda on the Cat monitors the oxygen in the gas-flow, the doughnut seal at the flexy joint isn’t too good at sealing, so under moderate cornering forces opens up, allowing air into the stream, the Lambda senses a lean condition, more fuel - burnt out Cat. Seen it loads of times.
Bear in mind, Lotus made a big deal at the launch of the n/a S2 Toyota that aftermarket exhaust firms had better be careful because they had optimised the manifold/cat pipe design and any mods would destroy performance - I still can’t quite work out if that was just a wind-up or if they really believed their own hype/BS.
But let’s take a closer look at the std 2zz-ge POS. It has short, 1.5"dia primaries, feeding a larger-bore secondary section using a splitter plate to make two secondary pipes. That design is common on bike systems. Yamaha have supplied a big-bore motorbike engine to Toyota - all revs/bhp and no torque. At 8500rpm, on the 2nd cam, the motor is shifting some amount of air. I venture more than a std K-series? I’ve just finished R&D on a new 4-2-1 for the K - I’m using 1.75"dia primaries, there is no loss of torque.
IMO Toyota use 1.5"dia primaries to enhance what little torque they have. Short primaries, mis-matched long secondaries - a disaster. It’s all very well to say, “Hey, it works!” any set of pipes will get rid of the exhaust gases BUT optimise performance - you’re ‘avin’ a laff!
My 4-2-1 design gave an extra 12bhp-10ft/lbs torque.
Looking at the SC installs; again, any set of pipes will carry the exhaust gases away but … If a tuner came to me and said “Hey, I’m thinking about a 250bhp motor - can you design an exhaust manifold for it?” I’d START at 1.75"dia primaries - not 1.5" - on a Forced Induction motor?! It’s not even funny. Look at the gains with the proper bore - 1.875"dia - is it a coincidence that Lotus themselves use this size of pipe on the 2-eleven racecar 4-1? I won’t comment on that design but …my inbox is still on fire.
How hard is the Supercharger working to pump the air through those small pipes? All SC installs rob the motor of power for their drive, I guess approx 30-40bhp at the top-end on the 2zz-ge SC? How much more pumping losses related to the small-bore manifold? How about the 25bhp I just gained?
Another pointer to how hard the motor is working is the drop in operating temps - 15deg - once my 4-1 is fitted.
Even an amateur tuner will tell you to look for a smooth entry to the exhaust manifold - have you had a look at the std 2zz-ge design? It’s embarrassing. A large chunk of money on its development? A large chunk wasted! Can’t be all that bad?! It’s 'kin worse than that mate.
Let’s take a wider look at the exhaust products Lotus offer.
Their Stg2 for instance. I’ve had owners change five or six under warranty. Burnt out, droning, rusting. Their Stg2 (sometimes referred to as the Stg3) for the SC installs? - again, I’ve got e-mails/phone calls telling me of a loud/droning exhaust.
I could go on and on … just don’t get me started.
Owned !! :whistle: