Hi
At the moment I'm still deciding between supercharging and turbo, so I'm still gathering info on both.

The Question is, is it worth using extractors on a supercharged engine or is the money better spent elseware?

If they are of use . Which ones work better,
The 4 into 1 ?
or
The 4 into 2 into1?
Thanks Col

 

uh yeah the better exhaust flow the more hp you will make but of course if you go turbo the header will be useless as it will get chucked for your manifold. overall long tubes build better torque. do a search on m.net several people running headers there soflarick also has dabbled in them abit.

 

How did you know he was talking about headers? I was like, what's an extractor.

If you're running a coldside, you can use any header you want. The RB 4/1 or the Fujiracing 4/1 are great. If you run hotside, then your only option at this time is the Jackson Racing 4/2/1, an ebay knockoff and hope it fits, or the old RB 4/2/1. Some old articles I've read show the RB 4/2/1 performs better than the JR header. Oh, the Bosal 4/2/1 also fits. I used to run the Bosal header, then bought a used RB 4/2/1 from a friend. Don't forget a header blanket if you're hotside. The header will otherwise cook the blower.

 

Hi
Sorry in Aus, headers and extractors are the same thing, Some people give slightly different definitions of their exact design, but most people just group them all together.
If I go with the supercharger I will be running an eaton 90 sitting on the hotside. I will be fabricating the unit myself.
The racing that we do in Aus for motorkhana is much shorter tighter tracks than you use , mostly first gear with a grab of second now and then, with heaps of turns so tight handbrake is needed.
I also like to do track racing but as there are no tracks near me I'm stuck mostly with the motorkhanas.
I had already bought the gear to turbo the car before my first motorkhana and that first race made me think lag would be a huge problem.
So then I started looking into supercharging . And I'm still looking
PS: the eaton 90 is much cheaper over here than any other supercharger and with its larger size I hope to get a colder charge when going high boost.

 

An Eaton 90, eh?

Are you planning on running more than 300rwhp? If not, you'd be better off with the MP62, as far as Eatons are concerned.

 

Are you going to custom fabricate the header as well as the mounts for the blower? I believe Racing Beat used to use a 4-2-1 and now makes a 4-1 which they claim has better flow... but it's not designed specifically with forced induction in mind.
Unless you've got the ability to flow test them or have the time to fab up several designs and compare them on a dyno, just go go w/a 4-1 (easier to fab) and be happy.

I've got a RB for 1.6 I'll let go for about cheap if you'll cover shipping.
https://www.miataturbo.net/forums/sh...78&postcount=3
It's known that it won't fit w/the standard Jackson Racing M45 supercharger kit, so just be aware of that.

 

it wont because of #4.

 

I don't know what you mean by #4
I know the 90 is on the large size. My intent is to end up in the 300 league but I need to get it up and running to see if there will be any problems with the system and work up from there.
I intend rebuilding the base engine: port the head, adjustable cam gears, 81mm 4AGE pistons, light flywheel, act clutch, 8000 rpm, eaton 90, MSPNP ecu, knock retard, Water Inj, Large FMIC, As far as haeders If I have to I will make a set .
That is one of the reasons I asked if the tuned length makes much difference in supercharged engines, because it would be esaier to make them if I don't worry about the tuned length.
The motorkhana circuts I've seen on youtube over there seem much longer, Do your fastest guys usually run turbos or superchargers?
I ask this because I have all the gear to turbo the engine with a nissan ceramic ballbearing turbo and fitting this up will be a lot less work , although I will be limited to 12lb boost because of the ceramic turbo.
So I guess my question Is for a really tight bitumen motorkhana, What do you guys think would be the fastest setup??

 

runner #4. the exhaust port on the 4th cylinder. the extractor that exhaust from the last hole flow through....

 

Thanks for explaining.