boosted spec v

[Ericp]

very nice, that's going to be one hell of a sleeper. Did you ever get those SRT injectors?

[Big J]

Working on it. Money's tight, so I'm trying to find some performance wrenching to do to get the cheese. Which reminds me I need to call JB.

[Ericp]

yeah I know what you mean. I'm broke as shit. When I do get my hands on some money it will go to normal matience work. I got my Top End Modifier in the mail but I have to get a new valve cover bolt from Dodge cuz one of mine got welded to my support bracket for my oil line to the turbo. I got a big front mount comin sometime next week.

[Big J]

Allright childern, the cast manifold I used for my setup is from a new company, AutoBoost. Currently they only sell their products on Ebay, but they have manifolds for a about 10 or so diffrent motors. Why should you care? I'm going to be doing a group buy for the QR25DE manifolds on another fourm, $300 + shipping, if you want some more info PM me. They will work for SE-Rs, 2.5 altimas, and god only knows why but 2004+ Nissan frontiers w/ qr25de.

[~The_Duke~]

I would do that, but I dont have the fundage right now...

[Big J]

incase you're interested in a manifold

GROUP BUY LINK <---------click here

[Firefightin_tC]

Working on it. Money's tight, so I'm trying to find some performance wrenching to do to get the cheese. Which reminds me I need to call JB.

You damn right you need to call me!

[Big J]

I've already got 8 buyers in on this manifold group buy. It's going to close out pretty quickly. If you've got a 2.5 Altima, Sentra SE-R, (or even a 2004+ Frontier pick up) and you want in PM me.

[~The_Duke~]

I got whooped by Big J and the boosted Spec V...

Now that I have seen it in person, props

[Big J]

Yeah that pull from second gear was sick, the third gear was ok.........need a few more PSI, a boost sensor for my data logger, and a few good long highway pulls so I can tune it out a little better (3.5 PSI was fun for about 2 days)

and the open dump , I need to recirc that ASAP. I don't like tuning and not being able to hear the motor.

Good luck with the header.

[~The_Duke~]

Yeah that pull from second gear was sick, the third gear was ok.........need a few more PSI, a boost sensor for my data logger, and a few good long highway pulls so I can tune it out a little better (3.5 PSI was fun for about 2 days)

and the open dump , I need to recirc that ASAP. I don't like tuning and not being able to hear the motor.

Good luck with the header.

I have a feeling that kyle is going to demanding alot of beer after this one...lol

[nextelbuddy]

hey, nice to see your progress. got a few questions for ya though..

what are you using for tuning?

your car runs a MAF sensor instead of MAP and you are currently running your MAF sensor in BLOW THROUGH mode.. although this is good sinc you dont have to recirculate your BOV so your car doesnt spike fuel every time you let off the gas.. its bad because the stock MAF sensors aewre not designed to SEE any boost. thus any boost will cause your MAF sensor to max out really quick most likely causing bucking, hesitation and unreliable fuel delivery.


most people with MAF sensors run their MAF sensor in DRAW THROUGH where the MAF sensor is placed PRE turbo..


example AIR FILTER>MAF SENSOR>TURBO INLET of course when you run it in this method you MUST recircluate your BOV so that you dont loose any metered air.



if you notice almost all factory turbo charged cars with MAF sensors are running this method.. DSM, Supras, Skylines etc..


so back to my question.. what are you using for tuning?

[Big J]

SAFC, and soon injectors and an FPR. Noone has cracked the ECU so I can't scale the fuel tables for larger injectors, but I can drop the base fuel pressure to change how much fuel I have to pull to tune with the SAFC. MAF scewing changes the "load cell" the ECU uses, and to some extent timing, so the less correction I have to add or subtract, the better as far as the small timing changes that happen with it.

The blow through is good on THIS car for a few reasons.

1. Accuracy. The air intake temp sensor is made into the MAF sensor, so I'd rather the ECU compensate for the intake temps that the motor is actually seeing, rather than for air that has been comperssed, heated, cooled down, and was actually metered 6+ feet from the intake. The ricer in me wants an atmospheric BOV, but building a turbo for a car with almost no part support takes you out of the ricer catagory doesn't it?

2. The sensor won't max out untill about 15PSI, but the stock motor will blow at about 12.5 so I got some room. The SAFC corrections are allways pulling fuel so I could allways put the sensor in a larger housing to allow for a little more flow before it maxes out, and in the process get the corrections closer to 0. But I don't foresee building the motor anytime soon so it's not an issue.

3. On throttle lifts the ECU cuts fuel anyway, emissions, so it leans out but only momentarily, it did that N/A.

4. I could use a stand alone or a complex piggy back, but timing isn't a tuning safty issue, AFRs are the main issue. The ECU has VERY extended fuel and timimg maps, almost like it was mapped for forced induction, it takes it like a champ. Untuned I was running 11.9, I leaned it out to near 12.5 (I need to do some long highway pulls to fine tune it). SAFCs are supporting 300+ WHP with no real issues, so untill I really need to go that route I'm going to avoid it. Right now I'm only running a 3.6 PSI wastegate spring, so I'm way out of the turbos effficenty range, and I'm running the stock 2" mid pipe (see below), but it still pulls like a champ.

5. My initial goal was to boost it for under $1000, I spent $1052, the second grand will get me; 2.5" exhaust, clutch, MAP sensor for data logger and SAFC, guages, exhaust parts to recirc the waste gate, heat wrap and shield, injectors, FPR, a few other odds and ends, and some dyno charts. I hope to start doing more fab work to pay for it, and get 2 more rims, AVCR, and some drag radials. The only thing I couldn't do was WELD the aluminum IC pipes, but I cut, fitted, designed, and mocked them for my friend Shane to weld (boosted elements...shameless plug). I did all the other welding and fab.

I went through about every option, compared, researched, and what I went with is right for my goals and this car.

This is a little data logging I did (I recomend this logger, $279 can bo a fraction of what a good dyno tuning session costs), eventually I'm going to add the MAP sensor and convert my SAFC to use MAP voltage insted of TPS, again accuracy.

[Big J]

... its bad because the stock MAF sensors aewre not designed to SEE any boost...

Correct, nor vaccum. The element is in a window that samples a fixed portion or ratio of the air passing through the sensor housing. The ECU knows the element is seeing 1/100 (made up number) of the total MASS of air passing through the MAF housing. MASS is the total number molecules, density is molecules per volume. The "ideal gas law" states the volume of a given MASS of a gas is a function of pressure and temperature. SO, no matter what the PSI or tempature the MAF is still just metering mass.

[Big J]

New toy:





It's almost time......... again

[Firefightin_tC]

I call SHOTGUN! :thumbsup:

[Big J]

you start geting more parts rounded up and I'll honor the dibs

[Big J]

ohhhh I got some intercooler piping back......but my camera is in California w/ the girlfriend........it's some nice stuff

[Big J]

pics, enjoy.

I'll have pics mocked up for fit on the car when my silicone and t-bolts get here, grrrr.

[Big J]

[Da_unknown]

dam, looks good

[Ericp]

FUCKIN SEXY

[Big J]

Ok I finally went to the dyno, how's this for sexy:

these were the first two runs at 5psi so the motor was fairly cool, the best numbers I've ever seen at such low boost



the next two runs I did were at 8 psi, I added some fuel after the first pull to get it under 12:1


.....so after adding fuel to run 8 psi I did this pull at 6.5 and the AFR's were rich, around 11ish



so after pulling a little fuel between runs I ended up with this graph and a better AFR, but at this point, after 7 pulls, I'm sure heat soak was taking it's toll even though the numbers were better.



It's suprising what the diffrence between 5psi and 8psi feels like for only being 33 whp and 32 WTQ.

[Firefightin_tC]

Yummy.

[.gauge.]

Good stuff.

[Big J]

That's what a TQ curve should look like

now I just need like 1000 more RPM's

[Julio]

bad ass man! Clean work to...

[sleepys4]

Yea congrats on those numbers. Sick little torque curve.

[fox]

Wow. Glad to see it finally up and running hard.
Congrats.

[ksinao]

impressive man.

[Big J]

I'm pulling it back in to the shop tomarrow for a little this and that. Nothing major, just some stuff to control underhood temps, and a dual stage boost controller master ghetto tech style, and lower temp thermostats (yes stats, as in it has more than 1). If I have the time, I'll fab an intake to put the filter outside the engine bay, and a battery tray to relocate the battery to the fenderwell. These 100* temps have been hell on power output, but have been an excellent test of extreme conditions and durability, and it passed with flying colors. I'm more that happy with the performance, quality, and safety of this kit for it to be released to the public as is. I just got the skillz to make sure mine stays 1 up on everyone else.

No real major upgrades unitll I get some more supporting mods like a clutch/flywheel and fuel pump (fuel pump, yeah I know, whatever I'm broke)....... or more sponsors and/or another/different job.

The engine build is done on paper except for one little issue, but I'll have the answer to that soon enough.

You might be seeing a simiular engine build in Mike Kojima's 2003 Spec v time attack car............

[Big J]

Got some new numbers

5psi (my baseline, line pulled of MBC)

8psi

9psi