EMod Civic

I thought I'd share some pics of the tubular intake manifold I just finished for my 1986 Civic Street Mod car. It's a boosted D15a3, so there's almost no parts support for the motor. I started with a stock manifold and cut the flange off and built and welded the rest from scratch. These cars came with a really small throttle body and manifold, so I'm hoping this will free up some power. I haven't run the car like this yet, but hopefully I will get a chance soon. (I have to create maps and tune my 'Megasquirt' standalone to get it running.) Anyway, enjoy the pics, comments welcome.








-Chris (#11 SM - 7th place finisher at Nationals)

beepy

I always love to see DIY parts. Wish I had the equipment to weld aluminum.... Maybe I could make a similar manifold, since the Rio's manifold is a horrible design for boost. So far I have had to either build everything for my car, or adapt parts from other cars, including Hondas.

Also cool to see that you are so competative in SM. The class is so dominated by V-8 bruisers, it's good to see some small turbo cars getting up there.

EMod Civic

Man,

I wish it only took 12hrs to make. I think it was closer to 50hrs. A lot of the time I spent will never be seen, because it's now on the inside. I was working with a sawsall, angle grinder, die grinder, $39 drill press, and my TIG welder. The welding goes pretty quick, it was all the hand porting and blending with the die grinder that took forever. I can definately see why people sell these things for $800.

-Chris

GSRswapandslow.

those are some pretty damn long runners

Terrabomb

nice DIY

DaX

iTrader: (1)

Holy HVAC Batman! Just kidding...that manifold does look good! Like someone above stated, the runners do look kind of long though. Interested to see how it performs.

EMod Civic

Actually, the runners are about 2 1/2 inches shorter than the stock manifold, which points down from the head, then curves up and wraps around the plenum and enters from the back wall of the plenum. I did all the manifold calculations for resonance frequency, and the stock manifold resonated right at the stock engine's 5500rpm HP peak. This manifold should resonate at around 6300. I'm not at all convinced that the runner length makes much difference, but it seemed like longer will be best for keeping torque. Getting rid of the tiny throttle body and runners is by far the most important.

-Chris

baphomet

Looks great

youngkow

That is an amazing beauty. Good work!

qksl2

I made something similar, looks awesome! How did you polish it like that? Mine looks "brushed".




Yours looks better.

Ian

EMod Civic

I polished it by sanding 220-400-600-1500, then used some Mother's aluminum polish. Actually, my wife did most of the polishing. The worst part about the polished finish is that I had to spend a lot of time filing and sanding off all the nicks I made with my vice while building it. I should have used some pads between the vice and the manifold when clamping it - would have saved me a lot of time.

-Chris

qksl2

So it will stay looking like that? You didnt' do some kind of clear coat?

Ian