View Full Version : S13 SR20 Head Differences

08-16-2003, 09:33 AM
I have seen a post before about the Blacktop differences but i have a S13 Redtop and nothing was mentioned about them in the post, just S14 motors. Anyway it was a discussion about the "fins" on the front of the head, i have never seen a redtop with these and mine has them all the way down the indent of the head. It also said that if the serial number is XXXXX-80FXX then is was a late model or Kouki blacktop well, does anyone know what it would be ont the redtops? because mine reads XXXXX-52FXX. Thanks but i haven't seen one like mine before, and was trying to find out if it was one of the rare'er ones and if it was a late model S13 K's, or what it was, if i can get a bareing on around the year it was produced i would be really happy, Thanks http://forums.freshalloy.com/images/graemlins/grin.gif

08-16-2003, 10:38 AM
Its a late '93 or early '94. The end of the red tops. My 180sx is a 1994 180sx, just before the blacktops were released. My redtop came with ridges on the head, like a black top. Also, inside everything was identical to that of the black top. (the CAS gear is larger, other than that I can't find anything different except the O2 sensor.)

I have also seen some 93's with the same motor under the hood... ridges on a red top. This leads me to believe that the ridges came about near the end of the red top cars... and they had already upgraded the inside before the blacktop was even released. Like I said, the only noticable difference other than the valve cover color is the O2 sensor.... the red top uses the small one, and the black top uses the large one.

My friend also has a 1994 180sx, but his is a black top. I have extensive experience with both and cannot find anything better about his...

08-16-2003, 01:59 PM
You are correct...red top heads (assuming that the head is the original one that came on the motor) with ridges were the last of the red tops as the black top S13 motors were first introduced. In the US, one must be wary of people swapping valve covers and heads, and trying to pass off a motor as something it might not be...


08-16-2003, 04:07 PM
Is there a guide available anywhere that explains the differances between the heads and how to identify them with pictures. If one isn't available is it possible for us the members of FA to compile one and post it in the archives.

08-16-2003, 04:35 PM
Hmm... I've got enough people with different models of these things around that I could put together a nice guide on my website. Maybe I should do that. http://forums.freshalloy.com/images/graemlins/wink.gif

08-16-2003, 04:39 PM
You might want to toss that up so people can have something to refer to. i have a writeup but never got around to uploading it to sr20.hybrids.jp. I was finalizing the writeup on differentiating between S14 and S15 motors also.. there are minor visual differences...

08-16-2003, 04:46 PM
Do zenki S14 motors have the bolts like kouki S14 and S15 do? (the ones that hold down the valve cover)

09-19-2003, 05:33 PM

1bad have u made any progress with that list/guide?
just giving u a little reminder

09-19-2003, 06:30 PM
Nope, forgot all about it.

I should get around to that one of these days...

09-19-2003, 08:09 PM
http://forums.freshalloy.com/images/graemlins/tear.gif http://forums.freshalloy.com/images/graemlins/frown.gif

09-21-2003, 02:38 AM
Hey, if you have specific questions, ask me. I'm a busy man. http://forums.freshalloy.com/images/graemlins/smirk.gif