I have an EDM `89 Civic HB with 1.5l engine. Why does my registration card say 70hp when it should be 90hp for that engine? I know the D15B1 has 70hp but that`s the USDM model. Anyone have any ideas why it has 20hp less than it should? Talked to a mechanic who said many engines are "modified" to perform less (less HP) so that it`s cheaper to import these cars (in my case, to Norway (country with VERY strict import laws) ). He also said that removing these "modifications" would be easy, could be someting that prevents air/exhaust flow etc... Any ideas would have been greatly appreciated

 

How many valves do you have? 16 is 92hp 8 is 70hp.

My engine block reads d15b1 and i have a 16 valve head.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 8psiover &raquo;</TD></TR><TR><TD CLASS="quote">

My engine block reads d15b1 and i have a 16 valve head.</TD></TR></TABLE>

Same here...is that from the factory?

 

My engine is an 16Valve, I`m positive (had 16v sticker on hatch when I got it....) Can`t be 90hp, feels too sluggish for that.... I`m just asuming it`s a D15B2 since the engine is 1.5l, haven`t found a "stamp" on the engine, looked everywhere, heard it`s located left of the exhaust manifold...? Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jisu009 &raquo;</TD></TR><TR><TD CLASS="quote">

Same here...is that from the factory?</TD></TR></TABLE>

Yeah it is. I am in the US.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by haholvik &raquo;</TD></TR><TR><TD CLASS="quote">

My engine is an 16Valve, I`m positive (had 16v sticker on hatch when I got it....) Can`t be 90hp, feels too sluggish for that.... I`m just asuming it`s a D15B2 since the engine is 1.5l, haven`t found a "stamp" on the engine, looked everywhere, heard it`s located left of the exhaust manifold...? Thanks</TD></TR></TABLE>

Well, I weigh only 140lb. Mine is a 1.5 too. Car is gutted in the back and im running 205 60 13s in the front. It feels peppy in first gear, after that.. well.

Here is a picture of where you find the stamp.

http://users.resentment.org/me...e.jpg

I had to clean off the dirt and dark matter off it to see it.




Modified by 8psiover at 10:32 PM 6/23/2003

 

Will try to find the tag on the engine tomorrow, it`s night here in Norway now. Thanks Will update you tomorrow....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by haholvik &raquo;</TD></TR><TR><TD CLASS="quote">Will try to find the tag on the engine tomorrow, it`s night here in Norway now. Thanks Will update you tomorrow....</TD></TR></TABLE>

heh alright

 

Cleaned the engine and it was a D15B1 Doesn`t matter, going to buy a VTEC engine at the end of this summer... Thank`s though...

 

I just figured this out like 2 days ago. The D15B1 and B2 are essentially the same motor. The only difference is that the D15B1 or Civic Std. (yes lower than DX) has different exhaust and intake manifold setups. The Std. manifold is like the HF manifold... it has the short manifold straight to a crappy cat = horrible power... The intake manifold has black plastic spacer below the throttle body... This simply restricts airflow by making the air passage even smaller than the TINY throttle body... I haven't measured it yet, but it doesn't look much bigger than 40mm =tiny, my d16z6 TB is like 57mm. These two restrictors could easily drop the 20hp we all are looking for.

I just did a MPFI swap with a z6 manifold so that part took care of the intake restrictors and I put a header on, so there's the other restrictor.

For easy power...
1. get a different exhaust manifold or header... even a DX header is way better!!! Or Chikara has their cheap one for like $120... which I have...
2. Take apart your intake manifold --- it's not hard!! Right with you take of the black resonator box on the top, you'll see a throttle looking plate... it's some dumb plate that doesn't help, only hurts... Take out the 2 screws holding it on and remove it... But first open in it once with the lever outside the intake. Notice how it only opens about 1/3 the way?? STUPID... no power coming from there... just take it out... it'll be cool.
3. Go further into your manifold assembly. Notice how there is the 1/4" or so black spacer below your throttle body... it's the main restrictor. TAKE IT OUT!! Now here is the kicker. Throttle body spacers are a good thing, they allow the gas and air more time to mix, and thus allowing a more complete combustion. By removing the spacer, you give the air/gas less time. What I would do (if I knew this earlier) is take the spacer out and grind it down, or port it (same thing) to match the throttle body. Then reinstall the spacer, and put it all back together. Don't forget to check all the connections with the vacuum lines and whatnot...

They you go!! 10-20 more hp, at the flywheel! You've got a DX!!

Good luck...

Jung

 

While this would help w/ hp, if you are serious about making more power, you should just go ahead and convert to MPFI. Also, along with the differences mentioned between the d15b1 and d15b2, they have different cams. Switching the cams, along w/ converting to MPFI and switching headers would cause a significant increase in power, making the engine as fast as (potentially) an Si.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jung4g &raquo;</TD></TR><TR><TD CLASS="quote">I just figured this out like 2 days ago. The D15B1 and B2 are essentially the same motor. The only difference is that the D15B1 or Civic Std. (yes lower than DX) has different exhaust and intake manifold setups. The Std. manifold is like the HF manifold... it has the short manifold straight to a crappy cat = horrible power... The intake manifold has black plastic spacer below the throttle body... This simply restricts airflow by making the air passage even smaller than the TINY throttle body... I haven't measured it yet, but it doesn't look much bigger than 40mm =tiny, my d16z6 TB is like 57mm. These two restrictors could easily drop the 20hp we all are looking for.

I just did a MPFI swap with a z6 manifold so that part took care of the intake restrictors and I put a header on, so there's the other restrictor.

For easy power...
1. get a different exhaust manifold or header... even a DX header is way better!!! Or Chikara has their cheap one for like $120... which I have...
2. Take apart your intake manifold --- it's not hard!! Right with you take of the black resonator box on the top, you'll see a throttle looking plate... it's some dumb plate that doesn't help, only hurts... Take out the 2 screws holding it on and remove it... But first open in it once with the lever outside the intake. Notice how it only opens about 1/3 the way?? STUPID... no power coming from there... just take it out... it'll be cool.
3. Go further into your manifold assembly. Notice how there is the 1/4" or so black spacer below your throttle body... it's the main restrictor. TAKE IT OUT!! Now here is the kicker. Throttle body spacers are a good thing, they allow the gas and air more time to mix, and thus allowing a more complete combustion. By removing the spacer, you give the air/gas less time. What I would do (if I knew this earlier) is take the spacer out and grind it down, or port it (same thing) to match the throttle body. Then reinstall the spacer, and put it all back together. Don't forget to check all the connections with the vacuum lines and whatnot...

They you go!! 10-20 more hp, at the flywheel! You've got a DX!!

Good luck...

Jung</TD></TR></TABLE>


Thank you! Will try it out for sure, just figured out a VTEC swap would cost too much.... Will let u know if I notice any performance gain....

 

of all the USDM 4th gens, only the D15B6 which came out in the CRX HF was 8 valve. all other engines, d16a6, d15b2, d15b1, were all 16 valve engines.

 

Would'nt it make more sense to just swap on the D16A6 (USDM Si),
head onto the D15B1/2. Then you get MPFI, better cam, better throttle
body and intake mani. ALL at the same time?
But aren't all EDM's , DOHC D16A1/2 ZC anyway?
Why the SOHC? Oh. wait a minute.
He said civic, right ? Not CRX?

 

Is there a chance you can post some images of the "how to get more power" process. Having difficulties following your instructions, stupid me... I`m just so new to this. Thanks....

 

No pics on hand, maybe later today... but all you need to do is take the four bolts holding the throttle body/injection stack off and pull out the restrictor plate.

The restrictor plate is 32mm !!!!!! Down from the throttle body's 44mm... I just put on my z6 intake manifold/TB and it's 57mm, that's 25mm bigger than stock!!!

Jung