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2004 Forester XTi
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Discussion Starter #1 (Edited)
I just did the impossible. I installed a set of phenolic spacers and took them off the very next day after I got my four lovely CEL's cleared. These keep the intake manifold from absorbing the heat off the engine (metal to metal contact); therefore, the air you pull into the throttle body will not be heated as much with the now cooler intake runners.

I purchased a sheet of black phenolic material (24"X16"X1/4") from Lee Valley tools in Canada and had it cut with my Dremmel tool. How did I get the outline? Simple, just picked up a pair (only one is necessary after I compared the two. Both gaskets for intake are same part #.) of intake manifold gaskets (hard paper material) and drew my outline with it. I installed it by taking off the airbox, setting aside the windshield fluid reservoir, unbolted the 4 screws holding down the intake from each side of the manifold, got a needle nose plier, stuck it between the manifold and engine, slipped on a long nut between each handle of the plier to keep the plier from closing/releasing the manifold shut, then replaced the gasket on each side.

As for drivability, I got a high idle right away. A 3000 rpm idle off ignition, slowly drops rpm until it reaches 1200 rpm, then the car starts shaking. Reset ECU. High idle right away again and same rpm drop. I looked at my crank pulley and saw that while the car’s shaking, the 22mm bolt holding the pulley is not centered on the pulley. Got in the car and took off with the high idle. At a stop light, my exhaust rumble is quite annoying and if the rpms go below 1200 I get a shaky car.

As for performance, I knew I was getting cooler air into the engine. The performance pickup is noticable. There were no ting-tang-ichi-walla-bang-bang noises. Every time I shifted, the rpm would move to 3000 rpm and when I pressed the gas, I’d get pushed into my seat more. I loved it until I got a CEL; feelings of hate, deceit, remorse, and regret engulfs me. Lazy as I was, I got it checked the next day only to find a family of four CELs; Chamber 3 missfire, Chamber 4 missfire, unexpected high idle, and idle solenoid malfuncion. I burnt the family of 4 to hell with the OBD-II scanner. Ha! Die!

Replaced Phenolic material with normal spacers (engine cool) and to my surprise, the idle dropped back to normal. Gracious! I have a set of DIY phenolic spacers for the EJ25 engine, who’s up for bids? ;)

The high idle? I have not a clue. Or maybe the distance of ¼” could cause the fuel spray to not perfectly spray NSYNC with the valves causing the high idle. That’s my only theory I could come up with at the moment. I have not any more clues for the missfires, malfunctions, or all that other stinky poo. Could I have been running lean at idle? I have no S-AFC or gauge to monitor that. But for the current time being, the spacer is gonna stay off my car. Feel free to shower me with all your comments or questions. I'll guarantee to not answer any dumb ones.
:stinky:
 

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13 Years of RS
2005 Toyota Corolla :(
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5,532 Posts
Did you put a gasket on both sides of the spacer? If you only had a gasket on one side of the spacer, maybe you had a leak between the spacer/manifold or spacer/head, whichever way you put it in there.
 

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2004 Forester XTi
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Discussion Starter #3
I didn't realize an air leak could've occured. I wasn't considering gaskets for the spacer, because I thought the spacer would've been a gasket. You could be right, but let's say it had a small air leak. Would that explain the high idle and missfires?
 

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2004 Forester XTi
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Discussion Starter #5
puckaveli said:
Here is a nice article on those. I have e-mailed that guy e few times with no response.
http://autospeed.com/A_0401/page1.html
Yup, that's where I found my inspiration. You know? I'm not gonna give up. I'm gonna try different things to make it work. I didn't use gasket sealant, I'm thinking I should to see if it was an air leak.
 

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The first ex-ex-moderator!
00 RS & GSX-R 750
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1,446 Posts
I got an e-mail back from Sean Morgan. He said if we can get a commitment of 20 or more they could make some up for around $100. Do you know if the manifold gaskets are the same on the phase 1 and 2 EJ25?

He read this thread and said you most likely had a vaccum leak at the manifold.
 

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2004 Forester XTi
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Discussion Starter #8
Whoops, haven't been back to my project lately. Thanks Puckaveli, if it's just an air leak, it should be easily corrected.

Uniquemotorsports is still considering it, but I've past that point. It took me $20 to get the sheet, a whole saturday and night, and 4 CELs... I'm not gonna quit. I just need some free time to work on it again. :)
 

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No Subie to see here, carry on
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109 Posts
Hi,

I've actually installed these on my car and have had them going successfully for about 20,000 miles now. The intake manifold is about 20-30 degrees F cooler while driving in traffic. I don't have the data posted since I moved not long after doing the project.

I can have some made for about $60 ea, but I need about 10 people that are willing to go in on it.

If you are interested, then email me at [email protected](nospam)hotmail.com.

edit: almost forgot... use yamahbond or hondabond 4 to seal the gaskets and you won't have a leak.

Thanks,
Chad
www.uniquemotorsports.com
 

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2004 Forester XTi
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Discussion Starter #10
Nice to know that these spacers can last a long time. I just put them back on with gasket sealant (make sure they withstand long exposure to fuel, oil, and heat) from the Auto parts store this past friday. It was an air leak the first time I put them on.

You can feel the extra torque down low and they didn't cause a CEL or high idle this time. Yay. Now I have to control the extra torque. The car wants to jump everytime I start 1st, 2nd, and 3rd gear. If you want a worthy cheap mod, then do it.
 

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13 Years of RS
2005 Toyota Corolla :(
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5,532 Posts
Sweet, my guess about an air leak was right after all! I am the coolest!!!!:p
 

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1993 Miata-T
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224 Posts
Subachad,
I noticed the spacers were for Phase 1 EJ25s, will the fit the phase 2?
 

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No Subie to see here, carry on
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Wow, this is old... I made up a few batches and sold all of them. They were more work than it was worth, so I stopped producing them.

You can make your own with a dremel, bansaw, or whatever your like, just get one factory gasket to trace and pick up some 1/4 phenolic from http://www.mcmaster.com/

I don't have the part number of the material.

Chad
93 2.2T
 

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The Thread Stopper
11 WRX, Matte black
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5,783 Posts
I still have a set for a Phase 1 engine if anyone wants it.
 

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13 Years of RS
2005 Toyota Corolla :(
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5,532 Posts
punker248 said:
Which are the phase 1 engines and how are they different than others.

I have an '01 RS.


Justin

Phase I is the DOHC EJ25 found in the 98 RS. You have a Phase II, which is the SOHC found in the 99-current, I belive. I know on the newest EJ25, they have gone back to a MAF instead of the MAP, but I don't think there have been any signifigant changes to the motor itself.
 

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Yes i know i have a SOHC map RS, what i was wondering is how would that make a difference for the spacers?

and would that prevent them from not working?

Justin
 

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The Thread Stopper
11 WRX, Matte black
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5,783 Posts
punker248 said:
Which are the phase 1 engines and how are they different than others.

I have an '01 RS.


Justin
The intake manifold bolt pattern is different.
 
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