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Old 10-18-2010, 12:32 AM   #1
blckout7
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Default Phenolic Spacers + cam question

Hey guys I've been reading about phenolic spacers and have gotten mixed results...apparently it's confirmed that they lower intake temps, but by blocking heat into the intake manifold isn't that heat getting transferred back to the engine making it hotter? Hotter engine giving out extra heat isn't that in turn going to make the intake hotter through convection? Just asking not sure if stupid question or not.

Are they easy to install, and where can I get them and anything I should be made aware of like fitment for a 06 2.5i?


I haven't done much research on cams but my friend was saying something along the lines that when cams are installed it allows for higher rpms which is fine in a manual car because you can shift at desired rpm, but he's not sure how they would work in an automatic....?

How much do they go for with installation (estimated)? I like experimenting with the car but I heard this is rather hard for someone not to technical....
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Old 10-18-2010, 12:37 AM   #2
PhilSine
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I'll answer your first question...

The engine is already hotter than the intake and does not rely upon the intake for a source of cooling. The heat of the engine will not be affected by the intake manifold in any direct way. The intake manifold will not be as hot and therefore cooler, denser air will exist in the intake manifold and then pass into the engine where it can allow the fuel to be burned more efficiently due to the higher oxygen content.
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Old 10-18-2010, 12:40 AM   #3
blckout7
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Thank you I was unsure and thinking of all possibilities lol
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Old 10-18-2010, 09:01 AM   #4
renyo
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1st Question: Yes, your thinking is correct. The engine will still heat up everything around it (and inside it -- the coolant). Conduction, however, transfers heat better than the other methods. The phenolic spacers provide a barrier against heat transfer due to conduction. Because of this the engine has a MUCH harder time heating up the intake manifold. Also, convection doesn't really work that well in this situation since, for the most part, the (intake) air is flowing from the manifold into the engine.

2nd Question: Cams don't specifically allow for higher RPMS. They change the valve opening and closing profiles (when they're open, how long they stay open, how long overlap is, etc..). If you rev higher, you might want to change your cams to take advantage of different dynamics that occur in the upper engine speeds, but it's not required. You can also get a set of cams that are cut to target a lower rev range too.

Now for the automatic part. You can shift an automatic. You can shift it by either manually moving the stick, or by using the accelerator. You can also redline an automatic. Barring the TCU possibly wondering wth is going on with the engine speed, you should still be able to use an automatic normally with a higher rev limit.
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Old 10-18-2010, 09:10 AM   #5
blckout7
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Interesting about the cams I think I'm definitely going to do the spacers just hope it's not to hard, the cams I'm iffy about I don't necessarily like high rpms I would rather a lower rpm cam but that with installation probably very costly.
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Old 10-18-2010, 09:45 AM   #6
blckout7
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p.s anyone have any experience with the intake manifold porting from grimmspeed? any good?
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Old 10-18-2010, 10:58 AM   #7
LetItSnow
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If you watch their time lapse videos, they do a gorgeous job. Is it worth it for the buck? You can probably choose better mods unless you're going all out. Of course, you could grab a die grinder, Dremel, or drill and do it yourself for a lot cheaper. You have to remember that the air in the manifold is traveling slowest near the walls, so unless they're creating some vicious eddies, it doesn't need to shine! I port matched an SVX manifold, and it wasn't too crafty.



If you care about autocross rules: Porting is allowed up to an inch from the manifold and head interface in Street Prepared, and is unrestricted in Street Mod and Prepared.
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Old 10-18-2010, 11:58 PM   #8
blckout7
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Spacers look hard to install lol or very time consuming
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Old 10-19-2010, 12:23 AM   #9
renyo
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Quote:
Originally Posted by LetItSnow View Post
If you care about autocross rules: Porting is allowed up to an inch from the manifold and head interface in Street Prepared, and is unrestricted in Street Mod and Prepared.
Since I do, did you mean Street Touring with the first one?
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Old 10-19-2010, 04:10 AM   #10
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Quote:
Originally Posted by blckout7 View Post
Spacers look hard to install lol or very time consuming
the spacers didn't take that much of my time when I was installing them. it did take me a good hour or so, but I took my time. the only problem I really had was taking off the old gasket.

it may be easier to remove the intake manifold, but I left it in, and had to wiggle my big hands through everything to get the spacers and gaskets aligned. all in all, it wasn't too difficult to do it.

I haven't noticed that great of a difference in the temps of the intake manifold, but I'm very sure this mod has given me better mileage - no joke, I gained about 75+ kms from adding this and borla headers.
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Old 10-19-2010, 07:57 AM   #11
EdHilario
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Did you do the headers at the same time as the IM spacers or separately?
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Old 10-19-2010, 09:05 AM   #12
blckout7
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Quote:
Originally Posted by shum_87

the spacers didn't take that much of my time when I was installing them. it did take me a good hour or so, but I took my time. the only problem I really had was taking off the old gasket.

it may be easier to remove the intake manifold, but I left it in, and had to wiggle my big hands through everything to get the spacers and gaskets aligned. all in all, it wasn't too difficult to do it.

I haven't noticed that great of a difference in the temps of the intake manifold, but I'm very sure this mod has given me better mileage - no joke, I gained about 75+ kms from adding this and borla headers.
So what did you do just loosen the bolts lift the manifold up and slide them in?
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Old 10-19-2010, 09:45 AM   #13
LetItSnow
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The spacers aren't ridiculously hard to install. It is easier to do it with the manifold off, which is a good opportunity to do any port matching you want, surface treatments (grind off casting flash or unused bosses and tabs, or bust out a can of VHT Red Wrinkle), replace any older and potentially brittle hoses under the manifold and to clean out any oil that's accumulated inside it.

Remember, it's all aluminum in there. DON'T OVERTORQUE! IIRC the rating is 17-19 ft-lbs - not much! A little never-sieze probably wouldn't hurt, either.

FWIW, on the EG33, the manifold on spacers will collide with the AC line coming off the compressor and needs a notch in a rib, and the EGR line needs to be extended. Be prepared for stuff like this that may apply to the EJ.

As for autocross, per the 2010 SCCA SOLO rules:

STOCK: 13.10.D disallows port matching altogether.
STREET TOURING: 14.10.C allows intake modification up to, but not including, the throttle body. (Mostly your CAI, SRI, etc.)
STREET PREPARED: 15.10.U allows intake and exhaust ports and manifold openings to be matched, but only within one inch of the port/manifold interface.
STREET MODIFIED: 16.10.D.2 lets you have practically unrestricted fun.

This is where a measure of sportsmanship comes in. If your local region's ST competitors think that port matching on (assumed) a streetworthy, otherwise ST NA '98 Impreza will let you walk them, then they're really stretching. I don't advocate rule violation, but I won't be the first to say that the classing and PAX is not a perfect system. Just be sensible.
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Old 10-19-2010, 05:28 PM   #14
renyo
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Yeah, that sounds like what I remember reading. Unfortunately, I haven't the money to do the port matching or the autocrossing at the moment, but thanks for the info regardless. I do intend to do much more in the future though.

For the record, I was asking because of this...
Quote:
is unrestricted in Street Mod and Prepared.
Thanks
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Old 10-19-2010, 06:30 PM   #15
GrimmSpeed
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From our experience with our customers our phenolic spacers have gotten rave reviews. Many companies create spacers that are made out of basically cutting board material, the white ones, and these deform and cause leaks over time. We use phenolic material that is extremely hard and durable and kills heat transfer. We have had multiple customers say that with the 8mm phenolics and a coated/ported intake manifold and TGV deletes they could race their car hard like auto-x and stop and rest their hand on their intake manifold and it was not hot. Lower intake charge temps, I think so!

Will
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