Scott's Altima Coupe 2.5L Turbo Build

[white_spec-v]

Hey Scott, i was lurking around here and found this. Pretty cool someone is actually taking the initiative and boosting a 2.5 alti.

I have a boosted 02 se-r spec v. hella fun to drive daily.

heres some advice...

seeing as the qr isnt any different between the altis and sentras, you WILL make more then 230whp. your motor CAN handle 300whp with a nice tune.

the manifold you bought is a good mani for the price. its a replica of the Autoboost manifold. that company is no longer running though. I have the same mani

good choice on injectors!! simple plug-n-play thing

i would switch up that WG for a tial or turbonetics piece. the ebay stuff tend to get stuck shut and you really dont want that. overboosting sucks!!

bov, not my taste, but great choice nonetheless

intercooler looks pretty decent, should work fine.

the piping, if anything like the routing for the sentras, should be fairly easy to set up. just a few cuts here and there, and you should be set

the turbo might and might not last you. ebay turbos are a hit and miss game to get a good one. if you see any signs of the seals going bad, i.e. shaft play, i'd get it rebuilt with garrett internals. look up BlaastPerformance. they are in canada

Now onto psi levels..

5 pounds with a decent tune will get you the 230+ whp. maybe even more.

10 pounds with a decent tune will get you 280+ whp. depending on tune and trim of that turbo, you may just reach the 300 whp level.

12 pounds will be a for sure 300+ whp setup.

*this is all on stock internals. all the OMFGFORGEDINTERNALSBATMANFOR7PSI is a bit dramatic to be honest.

a have a local buddy that runs 9psi daily and 12 psi for the races. he has yet to blow anything. the qr is very under-rated when it comes to power levels it can handle.

I will suggest this, make sure all your vacuum lines for wastegate/bov/boost gauge/boost controller are routed 100% correctly. i'd have to say the vacuum lines are the biggest headache of the whole install.

i am assuming you are going to attempt this on your own. if so, give a whole weekend, as in saturday-sunday deal. i did my install in 13 hours from first bolt to first start up. but i did miss a couple small things. make sure you have everything 100%, no leaks all bolts/clamps tightened, etc before starting it for the first time.

I think thats all i have for now. if you have any questions i'd be glad to help ya out.

[crayzitalian3]

i think the only thing diff with the spec-v qr and our qr (altima 2.5) is that the spec-v's qr is built more for power, ours isn't, there are a couple things that are in the spec-v that give it that strong engine, so without those we can't really depend on another car too much unless its the same exact engine to the T.

[ESP]

*this is all on stock internals. all the OMFGFORGEDINTERNALSBATMANFOR7PSI is a bit dramatic to be honest.

Wow...that was a lot of really great info! One question about that though...doesn't the QR from the Spec V have stronger internals than the QR from the SER and the Altima? I though I'd read that in an article about the strengths/weaknesses of the engine.

[Rob.Vegan]

The best first post I've seen so far

Welcome to the forums white_spec-v

[QR25DE]

Yeah my buddy and I are doing it. He's has way more experience than me with turbo stuff. Yeah If everything works find I'll probably upgrade things such as the waste gate and the turbo. It would be worth it to make it last.

As for the boost levels I guess it depends on the turbo you are using etc. Either way I am happy to hear that the motor is built stronger than I expected.

I'm waiting on the boost gauge and AEM FIC. I'm off all day tomorrow so if the FIC comes today we can wire that in right away. I'm planning to get this all done on sept 5-7th as that's a long weekend for me.

Woot!! The excitement is growing!

[JDRosenberg07]

I highly doubt Nissan or any other manufacturer would build an engine and put the power anywhere close to the engines breaking point. To me that would just be ignorant to put the hp at like 175 when the engine can only be stretched to like the low 200's. Now I'm not saying It can or can't handle 300hp on stock internals because I just don't know that. But hasn't Nissan been known to under rate a few of their engines?

White_spec-v said he had an 02 spec-v which is several years old. Is it possible that back then Nissan used a QR similar to ours back then for it?

[QR25DE]

I've seen videos and other posts of 290WHP on stock internals. Check out Youtube, it's confirmed. Although reliability wise thats another discussion.

[2008AltiCoupeDan]

please... unclip the amber bro :P

otherwise---- gg keep it up and i cant wait to see when things start goin on!!!!

[QR25DE]

please... unclip the amber bro :P

otherwise---- gg keep it up and i cant wait to see when things start goin on!!!!

I know lol. Amber is staying though. If I could put amber in the tails I would. I like it plus it complies with my province's light laws. All cars soon in Canada will require Amber turn signals. I hate the red, especially when people have there brakes on and it's in the daylight. It's hard to see. I've almost hit a few people because I didn't know they were turning until I got up close. But thats a discussion for another thread and my personal preference haha.

All I can think about it's the BOV sound... LOL

[2008AltiCoupeDan]

i kept my amber bulbs in the turnsignals too wen i did my retrofit- but im talkin about the amber plastic parking light lol :P

in the wise words of PhEnoM- "I WILL break the amber" with his tiny a** hammer lmfao

[QR25DE]

i kept my amber bulbs in the turnsignals too wen i did my retrofit- but im talkin about the amber plastic parking light lol :P

in the wise words of PhEnoM- "I WILL break the amber" with his tiny a** hammer lmfao

Yeah that's what I'm talking about too. I'm going to keep it. I can always open the lights up and remove it if it's really bad looking. I think it's going to be ok with the black though.

[white_spec-v]

It is a pretty good first post. Lol

To my understanding, all qr25's have the exact same internals, cams, compression ratio, everything. What makes the difference in power between the altis and the sentras is the less restrictive intake, exhaust, and fuel/timing maps.

Nissan designed the qr, and did not change it til the 07+ se-r came out where the CR was bumped up to 10.5:1.

The 07 alti 2.5 even has the same exact power output as the spec v's of earlier years.

Now, back to the turbo stuff. I HIGHLY suggest you get a spare lower oil pan to tap for the oil return line before you start the install. Then keep the original incase you take the turbo off.

Make sure the oil return line is leak proof/air tight. There's no pressure in the line, but it will leak if not assembled correctly.

The turbo you have will most likely give those power levels at said psi.

The reason, is the qr has a relatively high CR for a turbo motor. Most factory turbo cars have a 8.5:1 ratio where we have a 9.5:1. That is a big deal when it comes to making power with f/I.

Now when you do the install, I suggest you put your lowest spring in the WG. I myself started at 3.5 psi(.25 bar) and I could barely keep traction in 2nd from a roll. So start small, gey a decent street tune on the fic then go up. Even if it's by 1 psi increments. It's night and day difference.

[QR25DE]

It is a pretty good first post. Lol

To my understanding, all qr25's have the exact same internals, cams, compression ratio, everything. What makes the difference in power between the altis and the sentras is the less restrictive intake, exhaust, and fuel/timing maps.

Nissan designed the qr, and did not change it til the 07+ se-r came out where the CR was bumped up to 10.5:1.

The 07 alti 2.5 even has the same exact power output as the spec v's of earlier years.

Now, back to the turbo stuff. I HIGHLY suggest you get a spare lower oil pan to tap for the oil return line before you start the install. Then keep the original incase you take the turbo off.

Make sure the oil return line is leak proof/air tight. There's no pressure in the line, but it will leak if not assembled correctly.

The turbo you have will most likely give those power levels at said psi.

The reason, is the qr has a relatively high CR for a turbo motor. Most factory turbo cars have a 8.5:1 ratio where we have a 9.5:1. That is a big deal when it comes to making power with f/I.

Now when you do the install, I suggest you put your lowest spring in the WG. I myself started at 3.5 psi(.25 bar) and I could barely keep traction in 2nd from a roll. So start small, gey a decent street tune on the fic then go up. Even if it's by 1 psi increments. It's night and day difference.

1. You are very encouraging and it's great to hear from another QR turbo owner.

2. Thats the plan. Start out small and build up from there. No FIC today, maybe tomorrow...argh haha..

[JDRosenberg07]

Okay so i was researching a bit and im pretty sure the 02 spec-v QR and the 08 Alti QR were/are the same. The new spec-v's do have upgraded pistons and a cast resign manifold tho.

but i did find this in a technical artical about the QR

Quote »Beyond simple intake and exhaust mods, a light-pressure turbocharger or supercharger seems to be the obvious route for horsepower. Camshafts will be expensive because of the requirement for valve springs and different buckets to maintain proper lash adjustment. Five psi of boost on top of 2.5 liters, however, should make a lot more power and shouldn't cost any more than they would on any other engine. What do you know; maybe the V8 boys had a point about displacement[/quote]So a boosted 2.5 with stock internals is just sounding better and better

[QR25DE]

More go fast goodies today:







Battery relocation time (Temporary until I get a battery box tomorrow and we make a mount for the ECU):







Battery is not relocated to the trunk... and yes with proper fuses and what not. Picking up a battery box tomorrow and wiring in the FIC tomorrow as well. I'll post another update soon!

And yes, if you are wondering if the ECU bolts directly into where the battery tray is. It does perfectly. The holes line up exactly haha.

[mcheddadi]

thats what I'm talking about!all those 240sx guys where doing it for years and now it's finally our turn!

[gmont02]

yup yup

[DaCoupe]

keeep up the good work man, cheers to you for being the first one to take on this project.

[crayzitalian3]

where will you be relocating the battery, i kind of wish i had the skills to do this so i can build a custom CAI

[QR25DE]

It's in the trunk.

[Drift N Dragg]

Nice AEM.... I was thinking for my Setp I was gonna run a HalTech Power Sport 1000, But unsure about runing a Stand alone EMS.. But Man this thing can do EVERYTHING.. I am setting one up on a Friends Rx7... The EMS system is clean..

[PHENOMenalVinyl]

i hope ur not keeping that damn amber strip in there please for me take it out lol

[QR25DE]

Just to piss ya off Phenom it's staying in LOL.

Oh and we wired up the AEM FIC... 1 issue remains... pics:













Still need to tidy up the wires. Most of this is temporary so keep that in mind. Just wanted to test everything.

It seems that MAF scaling works, etc. 02 reads fine and so on. The only problem is... well two issues:

1. What f***ing firmware do I run for the slave chip.2. I get no tach/rpm signal.

Number two is the most biggest piss off. Everything is wired right but we need to find out WHY it's not working. This is going to be a hunt because no one seems to have tried this with a QR25DE before... argh. Ah well. We'll figure out something I'm sure...

[QR25DE]

Boost gauge pics:





It'll probably use the chrome surround as it matches the other air vents. Probably take that apart tonight or tomorrow. Working 3pm-11:30pm today, kinda sucks...

[white_spec-v]

looks good so far dude.

question, how does the fic read rpm? is it done through one wire to the back of your cluster? spark pulse? ignition coils?

i ask because my standalone system needs all 4 ignition coil signals to work.

i have 4 wires spliced into the 4 pinouts of the ecu for the signals of each coil, those are connected to a diode board and are merged into one wire. that one wire then goes to the standalone box and gives me the signal for datalogging and tuning.

if knowing how the fic read rpm signal, you should easily figure out why it isnt reading right.

[JDRosenberg07]

Okay so noob question here.. Is it necessary to have a boost gauge? I mean does it serve a purpose other than show? All it does is show you how many psi you're using correct?

[QR25DE]

Okay so noob question here.. Is it necessary to have a boost gauge? I mean does it serve a purpose other than show? All it does is show you how many psi you're using correct?

Technically you dont need one but it's better to have one. Then you can see if you are getting boost spikes or have any vac leaks etc.

I may get out of bed today and put in the boost gauge... my friend is working on ideas for the FIC but it seems hopeless at this point so we may have to go with an safc, thats the backup plan but we'll see...
Modified by QR25DE at 5:46 AM 8/30/2009

[AkAd3MiKs]

id enclose those wires with those inner duct hoses or whatever you call them. last thing u want is to have your ecu fried due to a short. also try reading up on hondata or uberdata. If you got the money hondata is best but uberdata is supposedly better than using a safc. If I recall right uberdata is just like burning a program or a chip into your ecu. Its been a long time for me but go read up on it.

[QR25DE]

id enclose those wires with those inner duct hoses or whatever you call them. last thing u want is to have your ecu fried due to a short. also try reading up on hondata or uberdata. If you got the money hondata is best but uberdata is supposedly better than using a safc. If I recall right uberdata is just like burning a program or a chip into your ecu. Its been a long time for me but go read up on it.

Those won't work either. The crank and cam signals differ from "regular" signals. Put it this way: Regular -> Pulse, Pulse, Pulse, etc. Our car: little pulse, little pulse, little pulse, BIG PULSE, little pulse, etc.

AEM FIC is now out of the car. There is no firmware or way to hook it up UNLESS you rig up a sensor and a toothed wheel/gear to put on the crank pully to read engine speed. Etc. It's really too much of a hassle.

SO....

What WILL work (we think). Is an Apexi S-AFC. I ordered one cheap from ebay, brand new. (Thankyou ebay once more).

Should be here by friday HOPEFULLY if it get shipped right away.

It's not the ideal solution but at least it will get it up and running, then maybe use megasquirt or something else down the road...

I'll update when I know more.

[QR25DE]

Boost gauge is now installed. TY MIKE! lol.





I'll get better pics later on... *waits on SAFC Neo*....
Modified by QR25DE at 8:24 PM 9/1/2009