DIY Phenolic Spacers!

[Dirk37]

Being captain cheapass, I don't like to spend money on anything I might be able to make myself, so the other day I thought I'd take a shot at making some phenolic spacers. And for an hours work, they turned out pretty nicely!


I had some 1/8 cheap wood lying around my garage so I decided I'd put to use. First I took the gaskets out of my car and traced them on the wood.

Next I took a tiny drill bit and drilled pilot holes in each penciled section. Then I took a router and cut out the penciled areas.

I happened to have an extra intake at the time so I made sure it all matched up. Now I messed up on mine because its way larger than the actual holes. This is a problem because now there's sharp edges in the intake which cause turbulence. It's a little noticable at low rpms but it's not too big of a deal. Next time I make these I'm going to get the holes much closer to actual size.

I had to cut some sections out of the middle and trim the corners off because otherwise the spacers will hit the fuel injector connectors.

Finally install them and torque them until it's snug! If you find the car is idling high / running funny, it is probably leaking so keep torquing it little by little.

The thickness of the spacer moved the intake up and I ended up leaving out the side mount bolts because I didn't want to adjust the supports. I also relocated the engine ground on the back passenger side mount to one of the top end tank bolts.

Now even after driving hard the intake stays just warm to the touch :sun: I have noticed a little increase in low end torque and it really makes you feel the runners open! My theory is that at the high load high rpms the amount of air coming in cools the intake even more and thus you get more air and more power

 

[sperold]

Nice write up.
The wood surprised me.

 

[Dirk37]

Thanks! I was pretty surprised too at how well it worked and that it didn't leak. It's only been a few days though so I don't know how well it's going to hold up, but it seems to be doing pretty well.

 

[rubydist]

plywood has a 90% chance of having vacuum leaks. there are all kinds of voids in plywood, so there are all kinds of places for vacuum leaks to happen.

 

[SHOdded]

nice handiwork! just make darned sure it doesn't "backfire" on you!

 

[SHO1]

plywood has a 90% chance of having vacuum leaks. there are all kinds of voids in plywood, so there are all kinds of places for vacuum leaks to happen.

Is what I was thinking has a good chance of happening before too long.

 

[Dirk37]

I'm going to try coating them in silicone hopefully before leaks start to form. One day I plan to make some out of MDF which should be much more leak-resistant

 

[LOUDSHO92]

plywood has a 90% chance of having vacuum leaks. there are all kinds of voids in plywood, so there are all kinds of places for vacuum leaks to happen.

Also wood compresses over time so it might come loose.

Good execution but wood may of not been the best choice.

 

[Dirk37]

Also wood compresses over time so it might come loose.

Good execution but wood may of not been the best choice.

Would some plastic rated for high temperatures be a better choice?

 

[LOUDSHO92]

Would some plastic rated for high temperatures be a better choice?

I would. You can get a sheet of Phenolic from McMaster Carr for not much.

 

[yamahaSHO]

Also agreed, the wood won't last long.

 

[tompumped]

I ordered a phenollic spacer for my chevy motor and it was wood but it was strange. It was layered and coated top and bottom in red paint or epoxy? The quality was good and it worked.

 

[Dirk37]

I would. You can get a sheet of Phenolic from McMaster Carr for not much.

I'll have to give that a shot!

plywood has a 90% chance of having vacuum leaks. there are all kinds of voids in plywood, so there are all kinds of places for vacuum leaks to happen.

You were right! I coated them in silicone today and it made a pretty noticable difference. I had assumed it was not leaking because my wideband didn't show anything significant, but after coating them it idled better and pulled quite a bit harder.

Here's what they looked like when I pulled them out

 

[Shovert]

Can do like me. [Before I know someone made them.] I used solid surface laminate. Got some scrap from local cabinet man. First it is chemical and heat resistant. I soaked in gas never affected it. Then took my torch to it. Took alot of head before it just kind of fell apart. If engine ever gets that hot I better be a long ways away from it.
Like you I used wood working tools, then cut my own gasket. [Saving money.] Sorry no pictures. Muairce

 

[yamahaSHO]

I'll have to give that a shot!



You were right! I coated them in silicone today and it made a pretty noticable difference. I had assumed it was not leaking because my wideband didn't show anything significant, but after coating them it idled better and pulled quite a bit harder.

Here's what they looked like when I pulled them out

That's because the wideband is showing you the corrected AFR. It's not showing you what your ECU is doing to get it there. Positive fuel trims would be very high.

 

[91PDXmocha]

A big problem is wood absorbs quite a bit. You can see oil/fuel soaking and bleeding into the wood already. I would remove it until you can find a suitable material.

 

[rubydist]

Can do like me. [Before I know someone made them.] I used solid surface laminate. Got some scrap from local cabinet man. First it is chemical and heat resistant. I soaked in gas never affected it. Then took my torch to it. Took alot of head before it just kind of fell apart. If engine ever gets that hot I better be a long ways away from it.
Like you I used wood working tools, then cut my own gasket. [Saving money.] Sorry no pictures. Muairce

Solid surface countertop material is an acrylic. Acrylic is not a good choice for this application either - it is a classic thermoplastic and its forming temperature is between 280-285*F (That means at 285F you can bend it like a wet pasta noodle, and since the engine coolant is around 200F taking heat out of the engine, there are plenty of metal parts over 200F.) and it will plastic flow at a much lower temperature than that with enough pressure. That means that it will take a compression set right away and your intake will not stay tight. You can keep retorquing it until you have it all squished out, but it will keep on moving with the kind of temperatures that are under the hood.

 

[Shovert]

Ok now I have something else to buy to get on the road. But thanks luckily not on the road and will not with them. Like said used a torch on it and seemed ok. But obviously I am wrong so thanks for letting me know. Thanks Maurice