S1 3800 (L27) heads
Thread Starter
Senior Member
True Car Nut
Joined: Jun 2007
Posts: 2,478
Likes: 0
From: New Lenox, IL

I would definitely bet on it and I don't gamble.
It'* essentially the same thing as a less dramatic HV3 on an L36. The HV3 takes about 3 inches or so off of the total intake runner length and really wakes the car up if you have a cam.
I suggested just making your L27 runners 1 inch shorter so that you are not making that drastic of a change.
It'* essentially the same thing as a less dramatic HV3 on an L36. The HV3 takes about 3 inches or so off of the total intake runner length and really wakes the car up if you have a cam.
I suggested just making your L27 runners 1 inch shorter so that you are not making that drastic of a change.
I've been trying left and right to wake up this engine a bit and nothing has made a big difference. Hopefully this small modification will bring out the potential of the rockers, CAI, exhaust, and ported Lim I have on there. hi5.
I'll get back to this thread later tonight on how it all works out.
Thread Starter
Senior Member
True Car Nut
Joined: Jun 2007
Posts: 2,478
Likes: 0
From: New Lenox, IL

So I've done it all. Is this what you were telling me to do?

I put it back in, went out for a drive, and noticed a slight increase in top end power. Not sure if its just me thinking there was an increase, but there certainly wasn't a decrease.
Perhaps I have to drive more to let the PCM get used to the changes. I didn't disconnect the battery after I did this. Should I have?

I put it back in, went out for a drive, and noticed a slight increase in top end power. Not sure if its just me thinking there was an increase, but there certainly wasn't a decrease.
Perhaps I have to drive more to let the PCM get used to the changes. I didn't disconnect the battery after I did this. Should I have?
Last edited by xtremerevolution; Feb 14, 2010 at 04:36 PM.
Yep, that'* what I was getting at. You could go further and remove the vertical sides of the runner that are perpendicular to the TB entrance.
In retrospect, I should have told you to scan for your maf flow vs. rpm at WOT before and after so you can see if you're pulling more air.
And as far as the pcm goes it wouldn't hurt but unless you're getting knock, you're probably at the mods peak potential.
Another thing is, if you can get a radius on the opening (especially near the center) you would get even more flow. You would be on your own for this though.
In retrospect, I should have told you to scan for your maf flow vs. rpm at WOT before and after so you can see if you're pulling more air.
And as far as the pcm goes it wouldn't hurt but unless you're getting knock, you're probably at the mods peak potential.
Another thing is, if you can get a radius on the opening (especially near the center) you would get even more flow. You would be on your own for this though.
Last edited by 95naSTA; Feb 14, 2010 at 06:08 PM.
Thread Starter
Senior Member
True Car Nut
Joined: Jun 2007
Posts: 2,478
Likes: 0
From: New Lenox, IL

Yep, that'* what I was getting at. You could go further and remove the vertical sides of the runner that are perpendicular to the TB entrance.
In retrospect, I should have told you to scan for your maf flow vs. rpm at WOT before and after so you can see if you're pulling more air.
And as far as the pcm goes it wouldn't hurt but unless you're getting knock, you're probably at the mods peak potential.
Another thing is, if you can get a radius on the opening (especially near the center) you would get even more flow. You would be on your own for this though.
In retrospect, I should have told you to scan for your maf flow vs. rpm at WOT before and after so you can see if you're pulling more air.
And as far as the pcm goes it wouldn't hurt but unless you're getting knock, you're probably at the mods peak potential.
Another thing is, if you can get a radius on the opening (especially near the center) you would get even more flow. You would be on your own for this though.
One big thing I noticed while looking at the L36 LIM. The runners on the L27 are a LOT longer.
Compare the two:
L36 LIM:

L27 LIM:

And to think that ZZP cut off 3" from their runners? Those are some extremely short runners.
Last edited by xtremerevolution; Feb 14, 2010 at 06:49 PM.
Thread Starter
Senior Member
True Car Nut
Joined: Jun 2007
Posts: 2,478
Likes: 0
From: New Lenox, IL

Thread Starter
Senior Member
True Car Nut
Joined: Jun 2007
Posts: 2,478
Likes: 0
From: New Lenox, IL

I'll let you know what I come up with when the time comes.
Last edited by xtremerevolution; Feb 15, 2010 at 01:12 PM.



