450-500 HP SR20 Turbo choice

[bardabe]

Hey Guys, hope you can help me make a decision.

So I am finally getting around to working on my car. I have an S15 SR20 I am going to forge, Block & head are already torn down but I'm just not sure if going with the VVL head will be worth the extra headache. I'm looking for about 400-420whp on pump gas and about 475-500 on E85.

I used to be a hardcore Garrett nut swinger but have been a borg warner guy for about a year now. I'm just having a hard time picking a turbo. I have experience with the S300SX line. (83/75's to be more specific) Love the way they spool & make power. I've installed 4 of those turbos and every customer loves them. the most recent was on an Evo X, which showed that it would be too laggy for my power goals.

the primary use of my car will be a weekend street class time attack track car. so it's not a hard core competition car just yet, I will be street driving it here and there. since my sentra isn't exactly the most exciting car to drive around. I'm looking for something i can see full boost around 4K RPM and not fall off at the top, obviously I'm going to over build the engine so it leaves me headroom for a bigger turbo in the future if things get serious with racing & i score some good sponsors. I'm really looking forward to a nice discussion about turbos. I know there is a pretty serious heated debate on the whole Garrett to Borgwarner deal right now. Here are the details on what is going to go on my block .

Block:
CP 8.5:1 Pistons
Crower Rods
WPC OEM Bearings
WPC Oil Pump (N1 or OE S15 depending on head)
OEM Main Bolts
OEM Rod Bolts (WPC'd)

if I go VVL Head I'm going going to clean it, do a valve job & install new Valve stem seals, VVL heads don't need much to make power.

if I do the S15 head it will have the following.
Supertech Springs & retainers
Supertech Valve stem seals
Supertech Overiszed Valves
Tomei Pro-Cams 260 dur w/ VVT
Tomei Cam Gears
SRVE Throttle body

on the manifold side for the turbo, i really think the Twin Scroll T4 option will be ideal since it'll give me room for growth in the future, so i was planing on a Full Race T4 Twin Scroll manifold with Tial MVS Wastegates, I don't want to limit myself to a T3 footprint & a T25 is much too restrictive.

I've really been looking at the Airwerks S200SX 7670 turbo. seems like it'll be a good turbo to get me in the door & getting back to racing. at $2550 through full race (MSRP) it really doesn't look like a bad setup including the waste gates; & ball park similar price of a Tomei Manifold, GTX2867 setup with allot more room for power without falling out at the top. (list price to list price obviously). i know if i was going to go with a Garrett turbo i would be getting a GT3071R for the duty, but i think the BW 7670 can do a better job, & get me what i need to get going now. I've already started my project & want to have my car running within the next two months so all the input from experienced members is greatly appreciated. I want to hear the guys who have first hand experience on 2L engines with similar sized turbos for road racing & street applications. although all input is appreciated i would highly prefer the one from people with real world experience with different turbos they would recommend. & the reason i haven't brought up a EFR turbo is because I hope to be able to use the Airwerks or Standard GT turbo as a stepping stone to evolve the car in the future for an all out race build.

-Juan

[EDacIouSX]

Hi Juan. VVL heads are super sweet but for the added cost I do not believe it is worth it for the power levels you want. Also, it is more efficient so I believe it will get things to spool faster and have a nicer curve but I don't know if its worth the extra money at this point.

260 cams seem mild for your power goal, i would say 270s or 264s but im no expert, maybe someone with a ton more experience can chime in on this.

[soundboy]

Go with the s15 head and do the upgrades to it.
Cams, springs ect.

You need fuel id1000 works excellent. Noting smaller than 1000cc imo. The spark on the s15 coils are the bomb. No need to upgrade
Personally I like the gtx3071r. The part I don't like is the powerband. Very poor at low rpm. After a certain point your golden.

[bardabe]

Hi Juan. VVL heads are super sweet but for the added cost I do not believe it is worth it for the power levels you want. Also, it is more efficient so I believe it will get things to spool faster and have a nicer curve but I don't know if its worth the extra money at this point.

260 cams seem mild for your power goal, i would say 270s or 264s but im no expert, maybe someone with a ton more experience can chime in on this.

from the amount of work I'm looking to put into the DET head to make it reliable in competition use it's roughly a 400-500 difference in price. the reason I'm not 100% on going VVL or not is because of price but more because if anything ever happens dealing with the VVL valve train is that much harder compared to a standard DET valve train. (scored cam, broken rockers, and so on)

-Juan

[PoorMans180SX]

I shot you a message, but I think the S200SXE is the turbo you're looking for.

http://imagizer.imageshack.us/v2/xq90/674/pZidMj.jpg

Unless of course you want to take the leap up to the 7163. A 7163 in the .80 T4 divided housing is arguably the fastest-responding 500whp capable turbo on the market today.

a double rocker guide conversion will make the S15 head reliable, but the VVL will definitely kill it in powerband production.

[jr_ss]

from the amount of work I'm looking to put into the DET head to make it reliable in competition use it's roughly a 400-500 difference in price. the reason I'm not 100% on going VVL or not is because of price but more because if anything ever happens dealing with the VVL valve train is that much harder compared to a standard DET valve train. (scored cam, broken rockers, and so on)

-Juan

You'll never break a rocker on the VVL motor. If you have a scored cam on the VVL, chances are you have other major issues, oiling being one. The VVL setup is a much more reliable head than the DET. I made 485whp on 93oct at 19-20psi of boost. Redline is set at 8250 simply because the factory P11 cams run out of steam there. A cam swap(which there are quite a choices out there) would net better spool, area under the curve and peak power.

[pbelltata]

The part I don't like is the powerband. Very poor at low rpm. After a certain point your golden.

[the head]

What are you looking at in the road racing arena, in a 450-500 hp 240sx in NASA series you are going to be up against some serious hardware.

[s14unimog]

I run a 20G, for over 2-years now, on my S13 SR20 and put down a little over 400whp @ ~18psi. It's a real solid, inexpensive turbo.

I little slow to spool if you don't have a good electronic boost controller though.

[bardabe]

What are you looking at in the road racing arena, in a 450-500 hp 240sx in NASA series you are going to be up against some serious hardware.

Haha who said this was for a 240SX? But yes street class guys are some what intense.

[the head]

I would doubt you would be putting it in something heavier and given NASA is all power to weight calcs for high HP cars you will still be with some heavy hitters. as for spool and all my old setup was an FP Big T-28 putting out 395whp at HKS wastegate pressure (about 1 bar) full boost was in the 2500 rpm range (it idled at 1200 so basically no lag) S13 SR tomei 272 hydraulics.

Just put my new mazworx head and solid 270s in running a GT2867R with the ATP external wastegate t-25 exhaust housing, we are hoping to keep it below 410 wheel with the new setup, which may require backing off my boost a bit.

[TEALSQUEAL]

Nissanaholic. There is a snowballs chance in hell your were turning a fp big-28 at 1 bar and making 395whp. I was on e85 with hks 264 step 2's a built head and @ 21 lbs. wasn't even close...

Crunch the numbers on the turbo and you will know quickly what it huffs out at. Especially at 1bar.

[240SXK]

from the amount of work I'm looking to put into the DET head to make it reliable in competition use it's roughly a 400-500 difference in price. the reason I'm not 100% on going VVL or not is because of price but more because if anything ever happens dealing with the VVL valve train is that much harder compared to a standard DET valve train. (scored cam, broken rockers, and so on)

-Juan

this is true, in case something does happen it is very hard to source replacement parts even for a p11 head, i had a really hard time finding the cam cap bolts that hold the oil squirters, had to find the japanese ve fsm still untranslated to try and find some dimension and specs but luckily someone with a blown up sentra came through the help but i would definitely buy a spare head just to use for parts in case you need to.

[the head]

Nissanaholic. There is a snowballs chance in hell your were turning a fp big-28 at 1 bar and making 395whp. I was on e85 with hks 264 step 2's a built head and @ 21 lbs. wasn't even close...

Crunch the numbers on the turbo and you will know quickly what it huffs out at. Especially at 1bar.

Well I am not going to dig up the dyno sheet from 2010 to prove to some lame ass on the internet what my car used to put down.

Clearly you did something wrong.

[Freddy]

I shot you a message, but I think the S200SXE is the turbo you're looking for.

http://imagizer.imageshack.us/v2/xq90/674/pZidMj.jpg

Unless of course you want to take the leap up to the 7163. A 7163 in the .80 T4 divided housing is arguably the fastest-responding 500whp capable turbo on the market today.

a double rocker guide conversion will make the S15 head reliable, but the VVL will definitely kill it in powerband production.

Has this turbo finally been released ?

[PoorMans180SX]

Has this turbo finally been released ?

I JUST received pricing on these turbos, and they are VERY affordable. So yes, they are officially released haha.

Shoot me a PM if you want a quote.