Hey guys i was just wondering whether i could get some insight into the manifold i'm making up. I've drawn it to see how it would look and how much room its going to take up.

Question: Is there much difference in flow between the two designs? Which one is better? Assuming there is enough room. Is it worth all the extra stuffing around going the second design?

DESIGN 1
The Standard Log style manifold, probably make the log a bit bigger diameter




DESIGN 2
Extractor type, dont really care about equal lengths as there is not enough room and its turbocharged anyway. May have to make the gap a bit bigger to get to the studs though.


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Which engine ?
Whats the Firing order ?

You want to separate the pulses comeing from the engine as much as possible, and need to time them so that they arrive at the collector one after the other .... (there are some real scary calculations on this - search google...)

Personally, I'd go with design one, but make the pipe slightly (maybe 1/8" ?) at each new "step" ... to allow for the now increased gasflow.. also helps a little with hot-spots and over-heating.. (if it was all one length, then the port nearest the turbo will almost be glowing, where the one furthest away will be a lot colder ... welcome to cracksville... population, you.

Enough room for 4 pipes in there ?
J

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Whats it for, Gti? Can't make a bunch of bananas and fit it up front and space the grille a little?

JC

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But he's thriving and striving and hugging the turns.

Yeah its for a G13B, Suzuki Gti + Turbo

The Firing order is 1,3,4,2 so for an extractor setup you need to allow extra length for cylinder 1, then 3...?

I havent actually got the engine in the car yet but i'm selling the manifold i have already for some extra spending money and while i was on the job of copying the pattern i thought i would keep going. I think my engine is going to sit as far forward as possible, just from the way the design has gone so far. Not sure about how much room i will have so i thought i'd go some sort of log. From what i can tell there is'nt that much difference. I dont really like the look of the swirl of pipes - add too much weight and space, and i dont really want to space the grill, although that silver van you can hardly tell.

I just made another one that is stepped. How would this one go compared to the first? Surely it would provide more flow and allow for the extra gases.

I don't think the look should come into it... they're designed that way for gas flow properties, not for the way they look - the extra 100 grams of weight you get in the extra tubing would no doubt be lost in performance with exhaust restriction if you went for a log...

the starlet turbo setup in a roundie only has the grille spaced because the turbo sits infront of the motor, by the looks you're planning on putting yours over the gearbox so you shouldn't have any space issues

here's how TurboOrangie has done his turbo GTi setup... infront of the motor


not that I know crap about turbos... but I've seen a few custom ones, and logs aren't the done thing

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did I tell you that I won a trophy?

This is my setup, very similar to your option #1. I spent much time debating what to do but ultimately restriction in room and other items in the way such as clutch slave cylinder and radiator inlet led me to the log.





It will all come down to room. I have to say your option #2 does look good though.

Dan

from, what ive learnt the fastest and shortest route to the turbo = lower rpm boost and the longer smoother it takes = big hit of boost later in the rev range
the second one would be effective if you used a twin entry turbo

i think either setup would work well even with boost comming later in the rev range.
ive been for a ride in a turbo gti mini and they scream even off boost, so you could drive it casually of boost but the power would be there when you need it

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