s13 RED TOP vs BLACK TOP..

[z-driver]

s13 RED TOP vs BLACK TOP?
what is the difference between the two?

horsepower?

anything?

[Indecisive]

redtop SRs came in S13\'s.

rated at 205hp.  

the blacktop SRs came in late model S13s, S14s and S15\'s

depending on the model, you\'ll get different power outputs.  

S15 having the highest output sitting at around 250hp I think.  

there\'s some other differences in the designs like cooling fins or not...or whatever between the different model SRs, but they\'re basically the same motor, just tuned differently.  .

[Nebuchernezzer]

True but more accurately:
The redtop and blacktop S13 motors are near identical.  There are some minor ECU and wiring differences but the mechanical parts, peak power and peak torque remained the same throughout.
The S14 and S15 SR20DET blacktop motors are a different beasts altogether, the S14 motor has a T28 or T28BB (jap spec S14A only), and VVT.  The wiring is more akin to the S13 though.  It makes 220hp or so.  The S15 motor has a T28 or T28BB (again this depends on model, not all jap motors have a BB turbo and very few oz specs have them, it doesn\'t really matter though the non BB S15 turbo is nice anyways).  And the wiring and ECU is a bit more advanced, the coils and ignitors are combined packs instead of separate, the ECU has some kind of inbuilt security as well (somthing like it needs a code sent from the body computer so that it will work or somthing similar).
If you are referring to the fins that some SRs have on the front of the head it seems to depend on which factory the motor came from.  Engines from the same years can either have it or not have it.  My 1994 180sx motor doesn\'t, my mates SR20DET Silvia did, but other cars from the same year as his didn\'t (1992 i think it was).

[drift_addict]

Just a little more detail here for you, but most of that is correct:

S13- Red and Black tops

Both come with the T25G turbo, with 7psi of boost, pretty much identical as far as everything else, both use 370cc inject. both 205HP, same 8.5:1 compression ratio, the difference is pretty much what car they come in. The Redtop is from the 1990-1993 Silvia K\'s and the 180SX. The Blacktop comes in the 1994-1997 180SX/Silvia.

S14 - Blacktop

Comes with a T28 with an A/R of 0.64 (S13 is 0.80), the inject. are a little bigger at 380cc, boost is upped to 8psi and puts out 220HP. Same compression ratio as well. This came in the 1994-1998 S14.

S15 - Blacktop

Comes with a 60 trim T28, ball bearing, and uses a T-04B housing. Inject. are quite a bit bigger at 480cc and the compression ration is higher as well at 10.0:1. Still at 8psi this puts out 250HP and comes in the 1999-present Silvias.

[n1-200sx]

don\'t forgot the heads.
the red-top and black-top have different intake runners. one is better for high horsepower do to it breathing better. i\'m not sure which has the longer intake runners but that is the one that is better for high HP. last i heard it was the older redtop that was a better platform for performance. do to it\'s longer intake runners. i\'ll try and find out and post the answer.