HP with basic mods on SR

For the RWD SR20DET cars! Sponsored by Wiring Specialties.
User avatar
Movingviolation240
Posts: 1862
Joined: Thu Apr 25, 2002 2:26 pm
Car: Big boost and flying are 2 of the 3 things I can't turn down

Post

Everybody knows how much HP a redtop and a blacktop SR make. But a lot of people have been asking 'what will XXX YYY and ZZZ mods give me at the wheels?'

We'll start out with the basics that most people do when they do a swap. FMIC, downpipe, exhaust, and an intake of some form. The most power your going to get out of this settup is about 240rwhp. The stock MAF and injectors both run out of grunt at about that level. Anybody who claims to have over 250rwhp with the stock management system is selling you a load of BS. Everybody also knows that the S14 motor has a bigger turbo (T28) but people fail to realize that this motor will run out of steam at about the same HP level since it shares the same small 370cc injectors as the S13 motor. Now the bigger turbo will be more effecient and spool up a bit quicker, but the peak HP is still limited by the crappy fuel system.

If you don't have the big front mount your going to have to stay down on the boost a bit (no more than about 10psi or your asking for trouble). This is going to put you in or around the 200rwhp level. If you ditch the downpipe your going to loose another 10-15hp and exhaust is worth 5-10.

Also a side note, the stock fuel pump isn't going to support over 8psi (if your lucky) so please don't try it or your going to end up with melted pistons. Upgrade to the Z32TT, Skyline, or Walbro as one of your first mods.

Now let's take our SR with the 'basic' mods (240ish rwhp) and stick a T3/T4 turbo kit on it like the one http://www.enjukuracing.com sells. With this settup your still going to be limited to the 240-250rwhp level due to the stock fuel system. But your going to be making those HP levels at a lower boost level (around 10psi) since the turbo is moving a lot bigger volume of air than the overworked T-2small. Let's throw on some bigger injectors and crank the boost up. 550's a Z32 MAF and some basic tunning will get us up to allmost 400rwhp but will be running on the edge of what they can handle. (it takes about 22psi to make 400rwhp with a basic 'big turbo' settup give or take a few PSI or HP). Now let's go play with the big boys and get up to the 460-480 rwhp range. Now your having to add cams, intake manifold, massive injectors and some really great tunning while still running in the 22psi ballpark. That motor will make over 400hp at as low a boost level as 15psi since it's opperating so much more effeciently.

This is all very basic info, and it's not even half as simple as I make it out to be, but if your a noob it should keep you from getting flamed if you read and understand this from the start. There are also some great articles on turbo's in general in SCC (the suck squeeze bang blow series gets in depth with them pretty well). Please just search before you ask, I'm sure you can find you own answers (which is more satisfying than having sombody feed them to you and safer since you can 'grade' the source as to their credibility)

anyhow, happy boosting

Paul


User avatar
Movingviolation240
Posts: 1862
Joined: Thu Apr 25, 2002 2:26 pm
Car: Big boost and flying are 2 of the 3 things I can't turn down

Post

It has nothing to do with LBS of boost. PPL need to get over that, it's just a number. You could blow the thing up running 15psi on a T25 or make 500rwhp on a GT30 while pushing 26psi. SR's are going up to 500rwhp and beyond, so the limit is up there (with good tunning of course).

User avatar
Movingviolation240
Posts: 1862
Joined: Thu Apr 25, 2002 2:26 pm
Car: Big boost and flying are 2 of the 3 things I can't turn down

Post

P2Motorsport240sx wrote:So a bone stock sr20det block can hold 500+hp. Not a chance! Rods shatter, pistons crack, rings blow out, bearings spin, head gaskets blow out. So how much boost and or hp can a SR20DET hold with good tuning and without modifcation to the top or bottom end?


Uh yea, that's why 3 shops are doing it. All it takes is some cams and a headgasket (and maybe valvesprings if you wanna play it safe).

The limit with good tunning is still over 500hp, nobody's hit a real 'brick wall' yet. If you want to use stock cams you can still be on the wild side of 400rwhp (even with stock headgasket). All depends on how much dyno time you buy to set it up.

Paul

User avatar
Movingviolation240
Posts: 1862
Joined: Thu Apr 25, 2002 2:26 pm
Car: Big boost and flying are 2 of the 3 things I can't turn down

Post

Let me put it this way, before we started tunning on Ken's racecar it made a very impressive 214rwhp. After a few hours on the dyno tweaking the PFC he was over 490rwhp.

It makes all the difference in the world, from a car that makes 200rwhp and looses compression every 6 months to a car that you can drive everyday with 500rwhp.

User avatar
Movingviolation240
Posts: 1862
Joined: Thu Apr 25, 2002 2:26 pm
Car: Big boost and flying are 2 of the 3 things I can't turn down

Post

not really, just get rid of the cat alltogether, they REALLY hurt turbo car's (a lot more than any NA car)

User avatar
Movingviolation240
Posts: 1862
Joined: Thu Apr 25, 2002 2:26 pm
Car: Big boost and flying are 2 of the 3 things I can't turn down

Post

I've read that 10-12PSI is safe on a T3/T4 (from a reliable source) so I wouldn't worry about running 12-13 on a T-28.

GTS4-R
Posts: 765
Joined: Fri Sep 27, 2002 5:59 pm
Car: my feet
Contact:

Post

P2Motorsport240sx wrote:How many pounds of boost should a stock S13 motor hold with good tuning?


With a stock IC I wouldn't trust any more than 10psi and with and aftermarket FMIC those injectors can't push much more than 14psi......although I hit 15.4psi withthe factory fuel setup (except I have a Walboro 255iph fuel pump) once when i was tuning my E-01 BC......I wouldn't recommend more than 14 and thats still pushing it.....i think he outlined that above.....

User avatar
lessthanjakejohn
Posts: 4105
Joined: Fri Oct 25, 2002 6:39 am

Post

P2Motorsport240sx wrote:How many pounds of boost should a stock S13 motor hold with good tuning?


Say something like how many pounds of boost will a stock S13 hold with 100 degree intake temp.

User avatar
hokiruu
Posts: 745
Joined: Sat Dec 07, 2002 1:34 pm
Car: 2012 INFINITI M37X Platinum Graphite

'95 240sx/s14 SR20DET (in 2000) SOLD
Location: Northern CA

Post

I want to settle this for once and for all now where everyone should read it: Common sense suggests that the S14 and s15 t28s will push as much power at 10 psi as the s13 t25 does at 14. 14psi is max on the t25 and 370's, so is 10psi the safe limit for the s14's 370cc injectors? This also seems logical. However Enjuku told me I could push 14 on the S14 SR with stock turbo and injectors. Seems like wishful thinking to me. Wayne at Phase 2 also says 10psi is as far as you want to take it. Paul, what's the deal?

P2Motorsport240sx
Posts: 22
Joined: Mon Dec 09, 2002 10:06 pm

Post

How many pounds of boost should a stock S13 motor hold with good tuning?

P2Motorsport240sx
Posts: 22
Joined: Mon Dec 09, 2002 10:06 pm

Post

So a bone stock sr20det block can hold 500+hp. Not a chance! Rods shatter, pistons crack, rings blow out, bearings spin, head gaskets blow out. So how much boost and or hp can a SR20DET hold with good tuning and without modifcation to the top or bottom end?

Drakon
Posts: 314
Joined: Thu Apr 10, 2003 5:19 pm
Car: S13 hatch-SR+bpu's

Post

I think people need to get it ground solid in their minds that upping the HP on a car is not just a 2+2 =4 thing. and most things are not just plug and play. Tuning is always mentioned at the end but i think alot of people dont really get what that means. I dont have experience in it so i can let someone else explain but I have made sure i got the concept.

bvanev
Posts: 98
Joined: Tue Jul 22, 2003 4:57 pm
Car: Cars, Snowboarding, photography, Cars

Post

This is really good advice. I have met a few people that think they know what they are talking about. I don't know it all, but if you start asking a few basic questions, and have the general knowledge, obtainable from many books, you can get an idea of you to listen to, and who to blow-off.

User avatar
Hijacker
Posts: 15759
Joined: Wed Aug 13, 2003 4:57 am
Car: '92 240sx Convertible
'94 F-150
Location: Fredericksburg, VA

Post

the stock SMIC is good up to 12 PSI, but that's pushing it. an FMIC should be considered long before boost is cranked anyways. I feel they're more effecient than the SMIC's.

BTW, I am currently running 14 PSI of boost (only 12 reaches the throttle body) with the stock fuel pump and have had no problems with pinging or knock. The new walbro just came in the mail and it's going in tomorrow afternoon to give me a safer feeling for running that high of boost.

sellinANs13
Posts: 9
Joined: Fri Sep 05, 2003 7:18 am

Post

yo whats up paul. Havent talked to you in a while. Anyways I just wanted to say that it is possible to get over 250 to the wheels with a stock redtop with basics. This guy at our show named Tony had us install a sr in his coupe. He had a fuel pump, fmic, afc, full exh, and an airfilter. He put down 258 rwhp at 14 psi. This was after tuning it on our wideband dyno (fourth gear pulls, the right way). The car was able to run a 12.7 in the quarter and that was with an open dif. The car was pretty freakish though, but it is possible.

Peace, Dustin (from columbus OH)

deffe
Posts: 53
Joined: Tue Sep 16, 2003 9:40 am
Contact:

Post

Hi All US PPL!.

I just recived this URL from a friend of mine. I'm from Sweden my self (that's in europe ;)) so we got alot of CA18DET and SR20DET engines running around the blocks here.

anyway. I just wanted to tell you all a bit about my own experience and feal free to ask something you wounder about since I am not sure I will be fully able to explain it perfectly in english.

... Here we go.

first of. I got a CA18DET Engine with the normal upgrades and a decent turbo (Mitsu 16T #7). I got about 280-300Hp(depending on boost pressure) with stock internals and stock fuelinjectors.

How you ask?.

Well it is simple. Just drill up the matallic tubic thingy that the MAFS is mounted on and that way you will be able to fool the MAFS to think that the car is getting less air then what it is actually getting.

Then you got a new problem the Fuel.. the car will need more fuel since it's now getting more air.. For that, just get a normal fuel pressure regulator. I got it set for 1:1,4 wich is working very well for me.

Also. Regarding the boost and how much you dare to use.. I use 1,5Bar without any problems and a friend of mine with about the same mods is loading 1,9Bar and he got ~320Hp and that's on paper to back it up.

So.... That's that.

toledo240
Posts: 572
Joined: Sun Sep 28, 2003 12:42 pm

Post

Movingviolation240, hey whats up? umm I was wondering on your input on high flow cacs? Are they worth it if you have the downpipe and exhaust?

User avatar
karay240
Posts: 209
Joined: Wed Dec 10, 2003 4:14 pm
Location: West Covina, CA

Post

I don't think that it's a matter of whether or not you CAN do it. I think it's a matter of SHOULD you do it, or how long can you do it. There are some people who seem to get away w/ running all kinds of boost , and the motor seems fine. Others crank up the boost just a little, and that's all she wrote. . . I'm not saying that you shouldn't raise boost levels, and have a little fun, but keep it reasonable. You may be the lucky one w/ the seemingly indestructable motor, or you may not be. . . you can find out the hard way, or you can take precaustions so you won't have to find out. I'll take the latter

User avatar
usdm_180sx
Posts: 744
Joined: Sun Dec 21, 2003 5:50 am
Car: 1993 base model 240sx (s13)
Contact:

Post

Movingviolation240 wrote:I've read that 10-12PSI is safe on a T3/T4 (from a reliable source) so I wouldn't worry about running 12-13 on a T-28.


Not with the stock smic...

User avatar
Zadok
Posts: 96
Joined: Tue Jul 29, 2003 3:50 pm
Car: '99 30th Aniversary Legacy L

Post

Last year when I called JWT, Jim Wolf himself told me that my KA turbo could do 300hp and an SR could do 350hp before things start breaking.I think they are a little conservative!Now, that was a year ago, and things have progressed, but what I really want to know is:

How many lbs of boost, on the stock T25 turbo\redtop, can a SOHC 240sx MAF support before it reaches it's maximum voltage output?Granted, that's the MAF that came with the car. I also have a Walbro 255, FMIC, and a 2.5" downpipe and exhaust.

My KA turbo was running about 14psi and tuned as good as it could be with stage 1 mods. I'm guessing it was putting out around 220 or so to the wheels.If I can get my SR to be that fast i'll be happy for awhile!

User avatar
Hijacker
Posts: 15759
Joined: Wed Aug 13, 2003 4:57 am
Car: '92 240sx Convertible
'94 F-150
Location: Fredericksburg, VA

Post

zadok, i'm running a SOHC MAF in my car as well (i wonder why seeing as how our cars were put together by the same guy ;) ) and I have been running 14 PSI on my T25 without any problems.

User avatar
Zadok
Posts: 96
Joined: Tue Jul 29, 2003 3:50 pm
Car: '99 30th Aniversary Legacy L

Post

And I believe you, but, I want to run my car totally safe.Which means, knowing all the numbers and pushing it the the edge and backing it off a little. I feel better doing that!That's why I want to know how much boost is too much for the SOHC MAF to accurately read.So I can go there, and back it off a little!It worked well for my KA-T!

User avatar
Cyberkreig
Posts: 3051
Joined: Sun Sep 01, 2002 4:40 pm
Car: 1993 240sx (SR )
Contact:

Post

i run 12lbs daily on an SOHC maf. I also have a walbro pump. I would run 14 without fear, except of damaging the turbo over time, something i cant yet afford to replace.

User avatar
tm_kickz
Posts: 588
Joined: Sun Nov 16, 2003 5:39 pm

Post

deffe wrote:Hi All US PPL!.

I just recived this URL from a friend of mine. I'm from Sweden my self (that's in europe ;)) so we got alot of CA18DET and SR20DET engines running around the blocks here.

anyway. I just wanted to tell you all a bit about my own experience and feal free to ask something you wounder about since I am not sure I will be fully able to explain it perfectly in english.

... Here we go.

first of. I got a CA18DET Engine with the normal upgrades and a decent turbo (Mitsu 16T #7). I got about 280-300Hp(depending on boost pressure) with stock internals and stock fuelinjectors.

How you ask?.

Well it is simple. Just drill up the matallic tubic thingy that the MAFS is mounted on and that way you will be able to fool the MAFS to think that the car is getting less air then what it is actually getting.

Then you got a new problem the Fuel.. the car will need more fuel since it's now getting more air.. For that, just get a normal fuel pressure regulator. I got it set for 1:1,4 wich is working very well for me.

Also. Regarding the boost and how much you dare to use.. I use 1,5Bar without any problems and a friend of mine with about the same mods is loading 1,9Bar and he got ~320Hp and that's on paper to back it up.

So.... That's that.


Could you email exact details on this. Im losing HP. I upgraded my turbo, and dont have enough money to get it all upgraded. Maybe your technik will work for now.

My email [email protected]

Thanks

User avatar
Movingviolation240
Posts: 1862
Joined: Thu Apr 25, 2002 2:26 pm
Car: Big boost and flying are 2 of the 3 things I can't turn down

Post

Untill you blow your motor up, don't forget they use 98 octan over there.....

Paul

dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

Post

japan and europe have different rating systems for their fuels movingviolation....98 there is like 94 or 93 here (in japan i mean)...im not too sure bout europe...but i do know its different to our system here as well

Hellion240sx
Posts: 793
Joined: Mon May 12, 2003 6:30 am
Car: 1992 240sx se
Contact:

Post

OK i just got confused... the sr20det (180sx/s13) is sohc????

dj_lennon_franz
Posts: 496
Joined: Wed Nov 20, 2002 2:24 pm
Car: 1992 240sx

Post

no the SR20det is twin cam

sr-engine name20-2 liters of displacementd-dual over head camse-electronic fuel injectiont-single turbo

Hellion240sx
Posts: 793
Joined: Mon May 12, 2003 6:30 am
Car: 1992 240sx se
Contact:

Post

oooooh ok (phew) thanks for clearing that up. go five post up to cyberkreig thats where i got confused, cuz it says he has a 93 sr under his avy... but then he's talking about whatever and sohc @15psi blah^3..... ahhhhh i see now maf. right

Mr.WideBody
Posts: 9
Joined: Wed Jun 16, 2004 8:46 am
Car: Gaming, and cars
Contact:

Post

Movingviolation240 wrote:Everybody knows how much HP a redtop and a blacktop SR make. But a lot of people have been asking 'what will XXX YYY and ZZZ mods give me at the wheels?'

We'll start out with the basics that most people do when they do a swap. FMIC, downpipe, exhaust, and an intake of some form. The most power your going to get out of this settup is about 240rwhp. The stock MAF and injectors both run out of grunt at about that level. Anybody who claims to have over 250rwhp with the stock management system is selling you a load of BS. Everybody also knows that the S14 motor has a bigger turbo (T28) but people fail to realize that this motor will run out of steam at about the same HP level since it shares the same small 370cc injectors as the S13 motor. Now the bigger turbo will be more effecient and spool up a bit quicker, but the peak HP is still limited by the crappy fuel system.

If you don't have the big front mount your going to have to stay down on the boost a bit (no more than about 10psi or your asking for trouble). This is going to put you in or around the 200rwhp level. If you ditch the downpipe your going to loose another 10-15hp and exhaust is worth 5-10.

Also a side note, the stock fuel pump isn't going to support over 8psi (if your lucky) so please don't try it or your going to end up with melted pistons. Upgrade to the Z32TT, Skyline, or Walbro as one of your first mods.

Now let's take our SR with the 'basic' mods (240ish rwhp) and stick a T3/T4 turbo kit on it like the one http://www.enjukuracing.com sells. With this settup your still going to be limited to the 240-250rwhp level due to the stock fuel system. But your going to be making those HP levels at a lower boost level (around 10psi) since the turbo is moving a lot bigger volume of air than the overworked T-2small. Let's throw on some bigger injectors and crank the boost up. 550's a Z32 MAF and some basic tunning will get us up to allmost 400rwhp but will be running on the edge of what they can handle. (it takes about 22psi to make 400rwhp with a basic 'big turbo' settup give or take a few PSI or HP). Now let's go play with the big boys and get up to the 460-480 rwhp range. Now your having to add cams, intake manifold, massive injectors and some really great tunning while still running in the 22psi ballpark. That motor will make over 400hp at as low a boost level as 15psi since it's opperating so much more effeciently.

This is all very basic info, and it's not even half as simple as I make it out to be, but if your a noob it should keep you from getting flamed if you read and understand this from the start. There are also some great articles on turbo's in general in SCC (the suck squeeze bang blow series gets in depth with them pretty well). Please just search before you ask, I'm sure you can find you own answers (which is more satisfying than having sombody feed them to you and safer since you can 'grade' the source as to their credibility)

anyhow, happy boosting

Paul


Great info, What kind of life could you get out of these set ups? Daily drivable?


Return to “SR20DET Forum (rear-drive)”