2ZZ Extractors

[yoshi]

Haven't a few people complained that after doing other mods that the transition into lift isn't as great as it used to be?

I have no complaints about medium rev range power, and would love the top end just to have a bit more...

On the other hand, more in the middle would make everyday driving better.

Edit: Spelling

[doriae86]

actually i noticed the biggest gains in the low to mid range with the ported headers

[Guni]

I, personally, would prefer more bottom and mid power for everyday driving because unlike some track warriors, I drive my car on the roads 95% of the time compare to track so time counts for squat. :)

On public roads, trying to make the time means making the fine as well, with mobile speed cameras on every nook and cranny of the victorian roads.

What I've done is ported stock headers and change to a free flowing muffler whilst keeping the stock piping. Seems to help with the low -> mid power. Kick into LIFT isn't as powerful compare to stock but I still feel the kick.

So question TRH, by frabricating custom headers, how much low - > mid can you improve in my case ??

Headers aside, do I need to go 2.5 inch catback as well to compliment these headers with a different muffler? What muffler?

Basically, my question is, what else to involve in order to "get there".

Thanks.

Edited April 20, 2009 by Guni

[thegourou20]

I am pretty much in Guan's boat. As far as I am concerned, I was to take off at the lights faster not actually catch up later (after the speed limit in case of street driving). It would not bother me to get some (a lot if possible) of extra torque while the lift stays the same at the top end. :)

[Brad-dreama]

Looks like I will be going to envy import which is close to me to get my stock headers done. I was going to get cess to do them but too much of a muck around and envy has done some nice work that I have heard of. Shoul happen within 3 weeks. Ill let you knoow how it goes

[SILVABULLIT]

I think most here want more torque low to mid range and are happy with the power top end. Stock ported headers give the gains you want as far as this is concerned. TRD headers will give slightly more top end over ported headers due to their slightly larger pipe diameter. Bottom end isn't as great off lift but peak power increase is minor dyno wise. Like 1-3kw from what i have seen.

Anything custom made above these will be a comprimise of losing bottom end to gain top end and vice versa. Depends on what you are chasing.

[Guni]

I think most here want more torque low to mid range and are happy with the power top end. Stock ported headers give the gains you want as far as this is concerned. TRD headers will give slightly more top end over ported headers due to their slightly larger pipe diameter. Bottom end isn't as great off lift but peak power increase is minor dyno wise. Like 1-3kw from what i have seen.

Anything custom made above these will be a comprimise of losing bottom end to gain top end and vice versa. Depends on what you are chasing.

Agreed.

Ported stock headers gave me feel through out the whole rev range but more noticable on the low mid because that is where we lack the most.

I seem to be quite satisfied with my current setup ............. for the moment but wouldn't mind trying something new!

Always the keen one to be part of future R & D ;)

[the_random_hero]

An update guys! I've been playing around with a different method of pulse tuning which has given me some interesting results. I knew my previous figures HAD to be slightly wrong as they didn't seem to correspond with any headers I'd seen previously made; the new figures give pretty close results to what I've seen from some well known Japanese brands (HKS, TRD, etc). Another good thing is they don't take camshaft profile into consideration TOO much, only where peak power currently occurs and how you want your torque band to lie. To change torque band is as simple as changing a single variable, which makes little changes SO much easier. I've designed a few sets for 4AGE (as I've got two sets of FWD headers I'll be starting on soon), tonight I'll see what a 2ZZ/1ZZ comes up with.

[Guni]

An update guys! I've been playing around with a different method of pulse tuning which has given me some interesting results. I knew my previous figures HAD to be slightly wrong as they didn't seem to correspond with any headers I'd seen previously made; the new figures give pretty close results to what I've seen from some well known Japanese brands (HKS, TRD, etc). Another good thing is they don't take camshaft profile into consideration TOO much, only where peak power currently occurs and how you want your torque band to lie. To change torque band is as simple as changing a single variable, which makes little changes SO much easier. I've designed a few sets for 4AGE (as I've got two sets of FWD headers I'll be starting on soon), tonight I'll see what a 2ZZ/1ZZ comes up with.

Good work!!

[1rocky]

great

[Evo7]

:toast: <my input

Evo

[the_random_hero]

I now have a full set of figures for a street and a 'race' set, I'd probably recommend the street set for most people unless you're planning on spending most of your time in lift (whitestivo? :P)

[thegourou20]

Cooooolllll....are they for the stivo? :-l would you mind posting the figures TRH? :)

[Guni]

I now have a full set of figures for a street and a 'race' set

What do you mean by street set and race set? Assuming then one gives you more down low in the rev range and the other on the high revs (for LIFT)?

What are the figures? Mind posting them up? Did you chuck it on a flow bench or on a test stivo?

[Suprathai]

Need some more concrete proof first mate, talk is talk.

Not dissing you or anything, its just the way it has to be done, as Northy has mentioned previously.

Personally I'm very interested in the development of this little project that you are undertaking.

[the_random_hero]

I now have a full set of figures for a street and a 'race' set

What do you mean by street set and race set? Assuming then one gives you more down low in the rev range and the other on the high revs (for LIFT)?

What are the figures? Mind posting them up? Did you chuck it on a flow bench or on a test stivo?

Street will give you more of a midrange boost than the 'race' set, which are more set up if you're willing to lose a tad of lower/middle range torque for a fairly increased higher end. All figures have been modelled with a handy little 'calculator' of sorts, it does all the pulse wavelength tuning for you - if you've seen the math involved to work out the timing between the exhaust pulses, you'll know why something like this is handy. I am going to combine this with another technique for adding a certain sized venturi at the end of merge collector, this will give you a broader range of where peak torque will occur for a slight loss in upper top end(we're talking poofteenths here).

Figures are merely the mathematically correct lengths of certain components of your exhaust which will give you the ideal scavenging effect at a certain rpm. I have no problems posting them up as it's not something that I can claim as figuring out on my own - it all comes down to how the headers are made to see the real results. The figures I've posted are the 'ideal' figures, which don't necessarily lend to pipe sizes and diameters easily available. The differences in lengths might not seem like a lot, but we're talking about a couple of thousand revs difference between where the best scavenging effect will occur in the two sets.

Race Set - 31" primaries/1.45" ID tube, 12" merge collector/2.5" tube

Street Set - 33" primaries/1.4" ID tube, 11" merge collector/2.25" tube.

I have a jig to make up merge collectors at work, I will start making one tomorrow as it's a fairly involved process.

[Guni]

Thanks for that.

Waiting for updates.

[moz]

Has anyone tried a set off these:

PPE Corolla 2ZZ Headers

PPE Install

They look impressive!

[Guni]

trh, have you got the specs for the stock 2zz headers to compare this to?

[the_random_hero]

trh, have you got the specs for the stock 2zz headers to compare this to?

I do not - if anybody has some, I'd be interested in learning their lengths. I got halfway through a merge collector on Friday in between normal jobs and a few last minute cars that came in, I'll try and finish it off tomorrow. I've got a couple of other projects I'm right into at the moment that are taking up most of my spare time at work, just trying to balance them out.

[Simo]

Once you sort it, let me know, and I will buy two off you*, one for my car and one for Nells

*that is of course if you will post to WA :P

[SILVABULLIT]

Pretty sure PPE stuff wont fit as it is for LHD cars.

[moz]

Pretty sure PPE stuff wont fit as it is for LHD cars.

are you sure? i only found out about ppe bescause people in oz are using them on their celicas

[matt_glad]

Pretty sure PPE stuff wont fit as it is for LHD cars.

Headers should fit as the factory headers are the same on LHD and RHD.

[Brad-dreama]

looks like your putting some good work into this mate.

any progress so todate?

im looking to get my stockies ported or ecu first.