S-15 Notch Top question

[(Yoshi)]

Hey, Im planning on getting an S-15 Notch top down the road and I wanted to know if I should use the S-15 transmission, drive shaft, and diff that comes w/ it, or if I should use the 5 speed that I already have along w/ the drive shaft and diff?

ThanksAdiosJosh

[spider_slayer]

why buy such an expensive motor in the first place? just get a redtop with a 5spd ... it will be cheaper and is more upgrade friendly.

better yet, if your bent on spending mad $$$ buy an rb25

[ca18det_boy]

spider slayer.....I'm mad at you........you still haven't come up man!!!!!!!

Now if your wanting the S15 motor you have to use the diff and drivetrain because the S15 speed sensor is in the diff. So if you use your current set up then you won't have a speedo. Now if you want....you can get the S14 notchtop.....its pretty much the same motor except it has a different turbo. Hope that helps!

[(Yoshi)]

spider_slayer I wan't an S-15 engine cuz first of all it will do up to 300hp stock on safe boost and its not done that often.

@ca18det now could I use a five speed transmission and then use the diff and upgrade the diff to a 2-way lsd?

[FattyMcBaggins]

You HAVE to use the S15 transmission and differential. I'm just about to start up on swapping an S15 SR into my S13, and I've spent alot of time talking to Jeff at Heavythrottle about these things. The S15 SR requires the 6-speed transmission, driveshaft, and differential. You also have to go to Dakotadigital.com and get one of their speed converter boxes to convert the speedo signal into MPH so it will work with the USDM Speedometer. If it's going into an S14 then you'll need to slightly modify the the transmission mount. S13 requires a custom one piece driveshaft or a modified S14 piece. Not quite sure on the details of the modifications needed yet, but I'll let you know once I start work on it. Hope this helps.

[virus77]

Get an s14 notch top and save yourself the trouble, both motors will handle the same amount of power in the end but the s15 has bigger injectors stock thats why you can push a bit more from it stock for stock. Its not worth spending thousands to be "different".

[(Yoshi)]

@fatty let me know how it goes

@virus could I use the five speed on the s-14 sr? and is the injectors the only thing different on the engine? I wouldn't be spending thousands more if I went w/ a s-15 sr as aposed to an s-14 sr. I would go w/ Heavy throttle cuz you get practicaly everything you need for the set up. This is copied from heavythrottles web site "S15 Black Top SR20DET complete $4850 plus shipping. Includes all electronics and ignition parts, uncut harness, transmission, driveshaft, differential, warranty and tech support." "S14 Black Top SR20DET complete $3600 plus shipping. Includes all electronics and ignition parts, uncut harness, transmission, warranty and tech support. " It would be just over 1k more to get the s-15 that comes w/ drive shaft and diff so Im basicly just paying for the driveshaft and diff...

Although I may go w/ the S-14 I don't know tho...
Modified by ViperSRT10 at 6:09 PM 12/13/2005

[FattyMcBaggins]

You get a helical limited slip differential, variable valve timing, 6speed transmission, and the ability to hit 300whp without having to swap injectors/reflash the ECU. If you get the s14 SR, you can use the KA 5 speed but you have to swap the KA bellhousing for the SR bellhousing. Somebody correct me if I'm wrong, but I'm almost certain that's what has to be done.

[justmerging]

don't forget about the custom driveshaft for the s15 swap. that's gonna run you $300-$500 on top of what you pay for everything from heavy throttle. Not really worth it IMO. For what your going to pay for an s15 swap to get 300ish hp you can get an s13 redtop to do 350-375. If it's what you want man have at it it just wouldn't be my first choice.

[FattyMcBaggins]

You only need a custom driveshaft if it's going into an S13. S14 uses the S15 drive shaft.

[justmerging]

His sig says he has a 91. I think that qualifies as an s13.

[FattyMcBaggins]

My bad, I didn't read his sig. Sorry!

[ca18det_boy]

yeah you can use a KA transmission but you have to use the SR bellhousing.

Now your thinking the right idea, just go ahead and get the S14 SR, and upgrade the diff. Let me know if you have any other questions.

AIM=ca18detboy

[(Yoshi)]

@ca18det Ill hit you up on aim over the weekend.

I haven't made my final decicion(sp) and wont for a while yet but the reason I liked the S-15 was that it would do stock for stock more hp. The reason i made this post is to know what I should expect. So the s-15 sr isn't my final its just one Im considering.

[ca18det_boy]

ok thats cool, I'll try and help you out as much as I can. If you can email me a list of exactly what your looking for out of your SR then I can try and have as much info ready as I can.

[virus77]

I dont want to beat a dead horse but with the money saved you can make more power from the cheaper motor. It wont be stock for stock (who cares about this anyways), but it will be more power for the same $$$$. you can get upgraded turbo and injectors and a tune or have a stock s15 motor. If you want to spend big money or have a better motor stock go for an RB25. I kick myself in the *** everyday for not going that route from day one.