Why Doesn't Any Company Make A Header For The 5SFE Options

[CyberCT]

I have been browsing this forum for quite some time and have noticed that NO COMPANY make a header for the 2.2l 5sfe. SSAutochrome was about to but then people backed out (and yes, I have seen claims of their poor quality with some products. Fortunately this header wasn't bad. There was one or two instances where they did crack or break though in the MR2 community, and that's about it).

I had three MK II MR2s with the 5sfe. I also had the SSAC header on one of them. Let me tell you the performance improvement was noticable right away. It was almost like night and day. More pull and it ran quicker through the gears.

When I had to put the stock exhaust manifold back on for inspection, the car ran much slower, easily noticable.

Now, the NA MR2 weighs in at @ 2650 lbs. The 94-99 Celica GT hardtop weighs in at @ 2450 lbs, correct? A good header would probably make it quicker in a line than the MR2, which felt good in a line.

Is there atleast a header in the works from a reputable aftermarket company?


I'm probably going to be buying a 6th gen celica in the near future as my new daily driver. Is there any place where I can see the yearly updates they did to the celica to fix problems from the previous year? Like for example, in 93, the MR2 fixed some electrical problems or quirks, and upgraded the suspension and other things. Is there a list like this for the 6th gen celicas?

[darksecret]

The main reason nobody cares to modify the 5SFE is because it's an economy engine, i've seen Snodgrass's 5S but he really doesn't have a lot done, see the biggest failure is the head and i'm at the point now where i'll sink the money to get a head flow test to show a stock GT head has crappy flow. When it comes to upgrading most people neglect flow and wonder why their intake doesn't give the 5 whp it claims on the box, well it's because it is bringing in more cfm's than the head and cam will allow, increasing the duration of the cam will increase the amount of time the valve is open, but that will not matter if the flow of the head restrict the cfm's the intake passage is capable of. So in to put it simply if your head and intake passage produces 125cfm but your cam duration only allows for 75cfm then you need to up the cam duration or lift, and if your cam is profiled to bring in let's say 85cfm but your intake passage is only capable of 60cfm then you'll pull 60cfm no matter how big of a cam you put in it. I can get more technical about this but i'm no head expert and it requires a little research to back my statement but this is head flow in a nutshell.