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ClassE 1989 325IS Build Thread


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Must have a hole in the floor for Fred Flintstone action.  There is no coolant hose from the overflow, and no cap/rotor/plug wires.  Also if it did somehow run, it would just idle along with no throttle cable.  I do however like the gold brake lines.

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The M20 is quite well optimized out of the box and in my opinion the two areas where people go horribly wrong on NA M20 builds is changing to a piston which does not match the squish area of the combustion chamber and not taking advantage of pressure wave tuning on the intake manifold. 

-short runner length/no plenum

-low air velocity at low rpm with itbs

-large camshaft required to match intake selection

-high compression pistons required to keep static and dynamic compression ratios happy due to large cam

-pistons without the proper squish area due to the requirement to have high compression as well as valve clearance due to large cam


It would be like disabling the VTEC system on a honda. It's removing the secret sauce that makes it perform the way it does.

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I happen to have 3 extra m20 intake manifold I could cut up and make manifolds with! 

I would very much so like to do a set of ITB's :) 

I could be the test dummy for this, and fabricate it as well, but I need a little help designing! Which throttle bodies would you use? Or would you build your own? 

I could start on this whenever! I would like to see an hx40 on my brothers e30 along with some ITB's. I  think it would be perfect. 

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 When I was toying with the calculations I believe I determined that the stock M20 manifold operated on either the 2nd or 3rd harmonic. If you guys are serious about a custom manifold then I would be willing to dive into it again for size/length calcs to see what it would look like or if its even possible to do a 1st harmonic tuned manifold.

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 When I was toying with the calculations I believe I determined that the stock M20 manifold operated on either the 2nd or 3rd harmonic. If you guys are serious about a custom manifold then I would be willing to dive into it again for size/length calcs to see what it would look like or if its even possible to do a 1st harmonic tuned manifold.

 

 When I was toying with the calculations I believe I determined that the stock M20 manifold operated on either the 2nd or 3rd harmonic. If you guys are serious about a custom manifold then I would be willing to dive into it again for size/length calcs to see what it would look like or if its even possible to do a 1st harmonic tuned manifold.

Yea I'm Seriously serious. I have the resources to produce a couple real quick. And I wan't one

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We can get back to ITB's later - I could use a hand sorting this out:

Well.... Might have found the culprit for my slight grinding from rear. Not sure:

Rotated wheel ends from both sides - couldn't hear anything troublesome, only noise was a slight "whine" from diff. So put new pads in passenger side and reassembled - turned over to same results. Put rotor back on drivers side and turned over by hand. "GGRRIIINNDDD"

Ruh-oh

Checked to make sure ebrake was fully disengaged, rotated again and got the same sound. Removed rotor and found these on inside of rotor:

AA5EDD52-B165-40F7-AF57-871A7C033B7B.jpg

2 separate cracks, about 60 degrees apart. I swapped rotors side-to-side and got same grinding.... So not sure if it's the issue.

Shoes are seated firmly against backing plate, springs seem to be under good tension, and brake appears to be operating normally. There was some heat cracking on shoes - but not excessive wear.

Thoughts?

Don't have a lot of experience replacing shoes/springs, so will have to do some research in the AM.

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I thought my grinding/noise was a poorly adjusted ebrake shoe until i ran the car on jackstands, put my head under the rear, and heard the sound was coming from the diff.  I have a different diff in the car now, soon i will see if i improved things...

 

I also have a irrationally massive hatred for the stock m20 intake manifold.  I dont care if i mess up any finely tuned Helmholtz resonance that the stock manifold provides, I want it out. It just doesnt look right to me and clutters up what could be a beautifully clean and simple engine bay.  Sign me up for any ITB development prototypes:)  I was also having turbo thoughts just last night to justify a manifold like this

baystg1.jpg

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I'm LOVING that intake mani above!!!

I wonder what the power band would feel like to run a intake mani like that NA, with the intention if running boost in the future? I'm assuming a slight lose of low end torque, but possibly a slight gain at higher end (depending on runner length and size). I'd want internal full bell radius stacks integrated into design....

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