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Discussion Starter #62 (Edited)
This thread is about the design for the header, not how to fix problems. Please start another thread if needed, however, the issue with the O2 bung facing the firewall is a well documented fact with the Megan/HP/OBX long runner/Alphawerk headers, nothing new and nothing $20-$35 cannot fix in under 5mins
 

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batlground.com. leave them an email if you don't see it listed, they will get back to you.
 

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Nice write up Kponti.

I will be running my SRT intake, HP headers/ypipe with stock bpipe and an Ltuned axleback exhaust. I will be getting cams, eventually. :rolleyes:

BTW, I dyno'd my SRT intake with just an Ltuned exhaust. And I pulled a 200whp with new plugs/wires/oil/tranny/diff. change ;)

I vote for this to be stickied, immediately ;)
 

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Discussion Starter #66
Nice write up Kponti.

I will be running my SRT intake, HP headers/ypipe with stock bpipe and an Ltuned axleback exhaust. I will be getting cams, eventually. :rolleyes:

BTW, I dyno'd my SRT intake with just an Ltuned exhaust. And I pulled a 200whp with new plugs/wires/oil/tranny/diff. change ;)

I vote for this to be stickied, immediately ;)
I think it will be a good combo!

In the meantime, I will lock this thread and sticky it till the end of the summer after I do some dynos to test out what I said earlier. That way this does not get muddied with too many offbeat posts that will take away from the goal.
 

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I'm bringing it back.
After hearing all the horror stories about the Obx and meagan setups not fitting, or o2 sensor 'clearancing ' issues, I decided this is not what I wanted. And since I'm new and can't get into the classifieds to find a mizzu or any of the decent fitting headers, I decided I would just make my own.

So I read through this thread, and found all the plus and negatives of the headers available for our cars.
The Meagan, seem to make the most power, terrible colectors and unequal legnth.
The mizzu's made good low to mid range, but fell off up top. But had a decent collector and were nearly equal legnth with nice long primaries.

Then I found a formula alot of v8 guys use.
One that takes into account :
Bore
Stroke
Valve diameter
Cam duration
Cam centerline
Opening degree
VE
Rpm
And of course, # of cylinders

Plug in all your 2jz info, assuming 90 % VE (which doesn't seem to affect much)
It's calling for a 31 inch primary legnth (mizzu), at 1.5 inches diameter (Meagan), and a 2.6ish inch collector (Meagan).

I'm planning on building mine with 15 or so inches of 1.5, stepped up to 1.625 for another 15 or so, equal legnth, with a pair of true 3 to 1 collectors, with roughly 15 inches of 2.5 secondaries to a single 3 outlet. This will be a 2-3 month project because it's my daily, and I'm in the army, but these are my goals. Will adjust fire based on inputs here, and fitment constraints.
 

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Well I'm still waiting to see the graphs on these, but if you look the primary legnth is still way to short on at least their catted version for our rpm ranges. I like them, they look great, but I'm looking for perfection, all the right measurements, not a compromise.
 

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I was considering the same thing, diy a header, but then there's the cost of materials, time, effort.. then i found some megans for $80 lol. relocate bungs no problem.

what's the point in a perfect NA header on a platform that doesn't perform unless boosted. megans aren't that bad, optimizing design , you'll gain what like maybe 5hp if that.

better yet, diy a turbo manifold
 

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I don't know, to say I did it. I just want to see how much I can wake up the car with some na stuff. I kinda want to get a head worked a little bit and go ahead and get the cams in and shimmed so I can just swap the whole thing one weekend. The headers and an intake would be the only things I couldn't use if I did end up going boost. The cams and any timing setup I decide on would both cross over if I do go boost, but I really don't think I can swing the money for a perfect setup right now.

I've seen 220 through a slushbox on here, with intake header exhaust cams and a gear untuned, there's at least another 10 or so in the tune. Theres not alot more that would be required to hit that 239 that seems to be the highest slushbox whp so far. I think something trick with the itake manifold, a slightly worked head, and a better designed header should get me at least the 10-15 I need to get over that number.
 

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I don't know, to say I did it. I just want to see how much I can wake up the car with some na stuff. I kinda want to get a head worked a little bit and go ahead and get the cams in and shimmed so I can just swap the whole thing one weekend. The headers and an intake would be the only things I couldn't use if I did end up going boost. The cams and any timing setup I decide on would both cross over if I do go boost, but I really don't think I can swing the money for a perfect setup right now.

I've seen 220 through a slushbox on here, with intake header exhaust cams and a gear untuned, there's at least another 10 or so in the tune. Theres not alot more that would be required to hit that 239 that seems to be the highest slushbox whp so far. I think something trick with the itake manifold, a slightly worked head, and a better designed header should get me at least the 10-15 I need to get over that number.
Take advantage of the slush box and start working on getting a shift kit, higher stall and gears in that rear differential. That will help deliver that 200 whp better to the ground with better 0-60 times.
 

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The shift kit is on the list, as for the diff id actually like to step down to the 5 speed 372 vs the auto 390 to spend a little more time in each gear, especially when making another 60-80whp over stock (final goal if all goes right) and use an emu to drag the motor out to 7k. There's no reason it should need to hit 3rd in 0-60.
 

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The shift kit is on the list, as for the diff id actually like to step down to the 5 speed 372 vs the auto 390 to spend a little more time in each gear, especially when making another 60-80whp over stock (final goal if all goes right) and use an emu to drag the motor out to 7k. There's no reason it should need to hit 3rd in 0-60.
Seems redundant to step it down unless you're boosting to stretch the gears out a bit. Not too sure what to accomplish winding it out on a N/A motor unless your strictly building a highway cruising or worried about MPG.
 

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I've seen 300 hp 2jz an , I've hit 229 in auto it's not easy and take a lot of work +$$$$ in the end I went boost .... You guys are trying to hard thinking about what has been done and thought about thousands of time already since 2001...
 
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