ST184 headers/extractors...?

[blah_00]

Hi! Just a quick question...just wondering if extractors made for the ST162 3S-GE can bolt to the ST184's 5S-FE? Thanks!

[roadsailing]

I highly doubt it.

[mullett]

Yeah, I beleive they had a totally different head design. Take some really basic measurments from the extractors (even the bolt spacing from the top holes, or the centres of the pipes will be a good start), and measure it against the stock. You can do all that with the engine in the car. If that's way out, then give up now. If it looks the same, you MIGHT have a start, but I really doubt it. Set of extractors should only be about 300-400 anyway...

RM

[RWDboy]

Yeah the bolt up fine 100% ... don't believe those other two.

[RWDboy]

It is however, highly likely that you will need to modify the front-pipe for the exhaust, or depending on the extractor design itself - come up with a new 2-1 pipe ...

[blah_00]

Ha ha ha...this makes it sorta hard...=) RWDboy...have you done this before...or do you know something the other two don't...? Coz they seem quite adamant...? Have you tried this before...? Thanks all for your input!

[Bahnugget]

i am also fairly sure that 3S-FE, 3S-GE and 5S-FE all have the same exaust manifold patterns... the head designs are differnt yes, but i belive teh manifolds are the patern

[RWDboy]

Yeah the head is *completely* different, but the exhaust manifold stud pattern and exhaust port spacing is the same.

If you are asking what *I* know that the other two don't ... well that's your answer ... I *know* that tey will fit, they are *speculating* that it doesn't.

I know this from many years of dicking around with 3S and 5S engines !

[blah_00]

Cool...yeah...that's really helpful...thanks a lot all!

[Nim]

Will a set of extractors help flow on a 5S-FE though? And FE head isn't exactly the most performancy of designs, so will extractors make any sort of difference? I know the 4A-GE manifold is fine untill you change the cams.

And are extractors for a 2.0 gonna be the right size for a 2.2?

[Bahnugget]

whatever gain (if any) depends on the design of ur factory headers.. they might be good already or they could be utterly shite

[Nim]

True. I'm just interested to know what sorta gain you'd get off an economy head like this one.

Anyone out there know?

[RWDboy]

There is no reason why a better flowing set of headers won't help on an 'economy designed' head (although i doubt you know exactly what that means).

[Nim]

*sigh*

A Toyota economy head (or FE head) is a close angle head to provide a nicer combustion chamber shape (better compression and easier to get good squish areas), but has the downside of needing to up the angle that the ports enter the combustion chamber, which is fine for low RPM, but an issue for flow at high RPM. It also has the downside of not having nice spacing for cam gears and timing belts, usually requiring some kinda crazy cam gear design, or lash adjusters (ala the SR20DET).

Also, if I'm not mistaken, most 'FE' heads have smaller valves and port sizes than ‘GE’ heads, which is great for low end flow, but sucky once the revs get high. Oh, and the cams have smaller lift and duration, making for better low end torque, but worse high end. This can be fixed by lumpier cams, and larger ports + valves, but then you might have issues with the valve hitting the piston, so you might need new cut-outs (seen it happen on Honda engines with bigger VTEC lobes and a shaved block - BAM, right into the piston). Anyway, that means engine rebuild time. And a 3S-GE or 3S-GTE engine swap is a much better option.

So now everyone knows what an FE head is, can we answer my question?
Are the limitations of the flow in the head itself going to be improved at all by a better exhaust manifold? Will the power be made worse by putting extractors that are designed for higher revs on a low revving engine? I’ve heard that the exhaust manifold on a 4A-GE are good and don’t need replacing before you get lumpier cams, so why woulda 5S-FE need upgrading?

Unless the extractors are just for the sound. Then go for it, but before you do consider that you might actualy lose power, rather than gain any.

[blah_00]

Ha ha ha...people on here really do know what they're talking about huh...? =) Thanks for all that...ummm...my next question was actually if extractors would be beneficial or not...now that I can assume they fit on the 5S-FE yeah...? Would they help with the 'lumpier' cams? (I'm not familiar with that terminology...does that mean higher lift or something...?) or would they just be a waste of time all together...?

Also, on a side note...so many people say it's such a waste of time modding the FE engines because of the 'economy' head...does any other manufacturer make engines this way...? I haven't heard anything like this for other engines, and I've heard of a fair few SOHC lancers and civics producing a decent amount of power...? I dunno...I just fully don't know much about all this, so if anyone could help...=)