I own an 88 N/A and I got my intake on tuesday and after installing it i noticed how little space there was for the Filter. There is basically a steal wall directly infront of my air filter and im wondering if the intake is getting any fresh air at all. I drove around town for a while to see if i saw any power diffrences but i did not notice any diffrence at all. So then the only quick method i could think of for getting a least some cool air into the air filter area, i took off my flash to pass headlight (the little mini headlight cover below the main headlight) And after doing that i noticed a change while going over 30mph.
I wish i could post some pics so you guys could see the set up beacause i just dont feel there is going to be any major changes in performance untill i get some fresh air into the intake area. Just thought id share some input on this system if any of you own an 86-88 2nd gen and were wonderin what the HKS was like

 

I doubt you felt any real difference, butt-dynos are notoriously unreliable. There's no path for air to get from the FTP hole to the filter, the metal bulkhead you mentioned is still there. It’s very difficult to get any fresh air to the filter without cutting metal. You need t make a heat shield to isolate the filter from the engine bay too.

 

Besides, I read a comparison somewhere and the HKS was the worst of all aftermarket ones out there.
And... I have said this before and i'll say it again, you won't fell any difference without a cold air box and maybe 1-2Hp gain with it at the high end.

 

Well thats exactly what i was thinking to do is cut a section out of that metal area but i wasent sure if i should do it do you think theres any disadvantage to cutting a whole in that section??

 

Can't see any disadvantage but you also need to block off the heat from the engine if you can.

 

I believe you are refering to this?

Filter comparison

 

Really?? Id like to see the reviews on the HKS system if you say its that bad. The only reason i got it is becuas the place i got it through got me it for their cost and i got i nice price on it but honestly where im lookin at anywhere from 2-7 hp diffrence i dought that the apexi or other higher rated intake system is gonna effect the already low gain im getting from this mod. I should add however that i have a completly free flowing exaust with no cats and a single N1 exaust, so maybe ill see more than just 2hp diffrence i Hope

 

If you read the comparison basically it shows that all the tested filters (Blitz, HKS, K&N, Apexi) give HP gains within 1hp of eachother but the HKS one had the worst filtering.

 

That websight was very helpful and yes i am defetly going to work on getting the filter isolated. As for the HKS ill prob end up getting the Apexi once the 10k is up on the HKS insted of getting a new filter.

 

Unfortunately these tests are more car specific than you think. A 13 hp gain on a 300+ hp car maybe but not on an old rx7 with less than 150 hp. The 13B needs less than 300 cfm if I am not mistaken. Now if you had some sort of ram air set-up by which you can change the inlet air pressure you will see better gains.

 

Worse than the fool, is the uneducated fool, of which I am too

 

The problem with those number is that they are peak versus peak differences.&nbsp If you've seen the actual dyno graphs (disappointed the filter comparo link didn't show any of them), the lower K&N might've had a wider powerband (in fact, I would put money it did), despite the lower peak hp gain...



-Ted

 

An open element filter is really just a piece of mind mod for the 2nd gen RX-7, especially the NA. It does become more important as the mods build up and airflow is more critical, but on the whole there is little advantage in installing it without exhaust/turbo mods.

 

so the HKS intake is not a good intake to get??
oh sh.t....
i just installed my too.

 

I don't know why people even buy that intake. You can buy an air sensor adapter for like $12 and a filter for like $35 and have yourself the same thing as the HKS intake. Once you buy a "kit" is when it gets expensive... :Shrug:

 

I actually only spent 100 bucks on it which was prob still too much. This is gonna sound stupid but another reason i got that intake is i heard it on my buddys 2001 accord and it sounded ****** awsome. But now that i know more about the two cars i assume that was cuz he has a v6 and the sounds from a rotary are a little diffrent than piston engines

 

My old HKS filter is sitting on my friend's garage floor...I didn't like the fact that the AFM is filthy inside now. I replaced it with a plain-old cone filter, and the flow seems good, and I'm sure it will filter better.

 

I've had the HKS filter for over 5 years, no problem what so ever. Big deal, right? Wrong, I did a ram air intake, where I placed the HKS filter right in front of the rediator. I had to clean the filter, every other week, it was so bad that the green section turned completly black after driving it for a couples of weeks.

Did I had a problem with the filter?
Nope!

Did I loose my engine because of the HKS filter?
Nope!

Was the filter in one of the worst areas, where you can place a filter?
yes!

The HKS is VERY expensive, where the KN is by far superior costwise, BUT if you already have the HKS, there is no NEED to switch to other filters..............

 

If the "filter" doesn't filter, then there IS a need to switch to something else.

 

Well as I said before, mine is in the worst place, and it has done its job. Otherwise I would've lost my engine by now, don't you think

 

Nah...I don't think you lose your engine from dirty air getting into it, but I'm sure you lose performance. My entire AFM was coated with black sticky sludge that the HKS filter let into it. Once I get about 2K mi. on my new filter, I'll take it off and compare, but I can't see it being nearly that bad.

 

Not the best pic, but I can't find the other one

Look under the tag, somewhat to the left, there it is, the mushroom hks filter.......

No problems what so ever.

 

How does the piping from the filter to the AFM look?

 

There are 3 "L" shape bents......... Not the most efective setup, but it sure beats heat soak.