I'm sure I will get bashed and burned at the stake for this post, but hey, these are my experiences and I am willing to share. All I can say is, try this combination if you are looking to stay N/A with a '05-'06 6MT (rev-up motor) and you will be pleasantly surprised with the results! I don't have time slips for the 13.55 or 13.61 runs as that evening no printed slips were given out (times and speed on monitor only). I do have have a 13.70 @ 104 run I will post up shortly.

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Here is a list of tweaks and modifications that it took to run 13.50s-13.60s normally aspirated.

Car: 2005 Infiniti G35 6MT (base 298hp)

Baseline best times: 4 to 6 runs 14.0-14.2 @ 99-100 ( And a few other not so impressive runs). Car had 1,500 miles or so.
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Parts installed:

Exhaust: Crawford headers, Crawford hi-flow cats, Fujisubo Legalis-R exhaust

Intake: Crawford plenum, modified throttlebody, Z-tube, JWT pop-charger

Drivetrain: EVO350 3.917 gears, UR crank pulley, Rogue Engineering shifter
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First I must say that my sedan was broken-in with lots of revs (no babying). Oil changed at 200/800/2000 and every 3,750 miles thereafter.

First place I looked for tweaking was the Crawford manifold. There were lots of casting flaws and the finish was not best for optimal flow. I first used an 80 grit sander paper flapper wheel and removed all casting flaws. There were several areas where the manifold did not exactly line up with the throttlebody so I then used a 36x grit sander wheel and matched the manifold to the throttlebody. At that point I used a 120 grit flapper and polished the entire inside of the manifold.

I then removed the lower plenum. I used the 36x grit drum to knife edge the intake ports and to remove all casting flaws. I then followed up with the 120 grit flapper and polished all the ports as smooth as a babies a**.

I then took the trottlebody and knife-edged the lip using an 80 grit flapper wheel, leaving approximately 2mm up to the butterfly. I removed the stepped bore and tapor bored it, finished off with 120 grit polish.

I removed the crank case ventillation tube that injects hot oily gases back into the intake by using a small K&N filter and plugged the Z-tube. This reduces intake temps.

I installed the Z-tube and JWT pop-charger. I then designed a rear half shield so that hot air would not be able to enter the filter. I then took a 2.5" holesaw and made a large hole in the fiberglass radiator shroud right in front of the air filter. Nice fresh ambient air! This mod alone was worth 1 mph through the traps!

The headers and high flow cats were installed by Crawford Z and the Fujisubo Legalis-R exhaust was installed by the dealer. I drove down to Houston and had the 3.917 gears set up.

I have Eibach Pro-kit and 19" Volk Progressive spokes. These wheels/tires are lighter than the stock 18"s in front and the 19" tires are only 3 pounds heavier on the rear. I'm sure the springs are hurting my 60ft times.

I removed everything that the car didn't absolutely need and weighed the stuff (jack, rod, spare, front and rear mats, trunk mat, trunk liner and foam, removable cup holders, and a few other items. This equalled 97 pounds.

Temperature was 65-67 degrees, high barometric pressure, low humidity (near perfect track conditions).

Fuel used: three gallons Exxon 93, four gallons TT105 unleaded.

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Observations:

In my opinion, the '05-'06 rev-up (298-300hp) engines respond much better to modifications than my '04 Base 350Z 6MT (287hp) and '04 G35 Coupe 6MT (280hp) did. There are a few glitches with the '05 that need to be overcome however I have found ways of getting around those.

The plenum added power under the curve as well as a kick at upper rpm. I tried it first with the stock airbox and a K&N. Then I tried the pop-charger. Without any other intake mods except the Z-tube, the stock box seemed to work the best. Once I ported the upper and lower plenum, and ported the throttle body I tried the JWT pop-charger again, but did the ram air hole in the radiator shroud and added the extra heat shield at the same time. I also added a 2" spacer to the front of the filter where it bolts to the mass air flow sensor. I then rigged a new brace for the filter assembly. There could be some pressurization of the air going into the intake area (a ram-air effect) now that I have a sealed box and the huge hole in the radiator shroud.

The headers and cats were installed together, so I can't tell how they worked alone. I do know that the combination of all three Crawford products on the '05 made a BIG difference.

However, I then had the 3.50 gears taken out and had the 3.90s installed. This is undoubtedly THE BEST modification you can do to a rev-up motored VQ. The biggest complaint that these owners have is the lack of low end acceleration. This is especially true when shifting from first gear to second gear (and 2nd to 3rd) as the revs typically fall out of the powerband and you must build rpm to feel the powerband. In short, the 3.917 gear ratio drops each shift right smack dab in the meat of the powerband.

With the above set-up I found that the factory ecu pulls alot of timing because it has too much advance. I was told not to do the reflash and I still haven't. To get around this problem, I add 3-4 gallons of high test TT-105 race gas. It makes a noticeable difference in overall power (around 10-12rwhp as observed). My A/F ratio is looks good (I dyno'd 285hp & 266pft @ the wheels on a 248E dynojet)

I increased front tire pressure to 50+ psi to reduce rolling resistance and put rear tire pressure at 37-38 psi. Launch at 2500-2800 rpm. rear tires are 275/30-19s S0-3s. The gear set makes it possible to leave at lower rpm and makes it much harder to bog, but much easier to boil the tires. Feather the clutch and ease into the gas. As soon as you do that, you have to shift. I do not powershift 1st to 2nd as this leaves too much tire spin. I can even bark the tires in 3rd and 4th gear (I powershift 3rd and 4th).

After all the mods, my best time has been a 13.551@105.52 (and a 13.61@104.81) and a slew of 13.70s in the 103-105 mph range). Still get the occasional 14+ when I boil the tires or miss a shift but you get the idea....

 

Nice write up. Seems like you had a lot of customizing to do. Those are some pretty good times for the sedan!

Do you still have your Z? Nice pic of the sedan, it looks great!

 

Nice times. Great write up. Maybe one of the fastest N/A sedans?

 

Very nice, I am impressed!!! The stock 635 sedan runs a 5.6 0-60, so those numbers are vear believable. Congrats! Great explanation!

 

Nice write up, but I have less mods and I run 13.13 @ 107 and 13.16 @ 106 And on street tires with my worst 60ft ever-2.2 I went 13.5 @ 106. And I dont have headers, a TB or the gears.

 

How many runs have you made at the track? I've made only 20 passes total including my baseline runs. I'm sure with some practice I could whittle those times down. One thing is for certain, the gears make consistancy much more difficult on street tires. With some 17" street legal stickies I'm sure the gears would really shine as far as 60ft times and as a result, my times would drop. Didn't you use slicks to run the 13.1? Your car is also considerably lighter than mine. I don't have any ECU mods or a lightweight flywheel or an aftermarket clutch. I do know how much the Tilton helps (I've used lightweight flywheels in other cars I've owned), but I'm not sure if I could handle the noisiness. I wouldn't count the throttlebody mod as a new throttlebody (it has the same butterfly size as stock). Also, I can pass a roadside smog test, can you?

Those are some very good runs by the way (for what you have done to your car)...

 

No, I sold the Z to another board member.

I have two little baby girls so I needed a baby hauler!

Thanks for the compliment on the sedan, it's been a work in progress.

 

EDIT: Wow I didnt notice you had a G35 man Im sorry. Your times are awesome given your weight disadvantage. I apologize I would have never compared my times to yours, I didnt catch that the first time. Great times and traps out of an NA coupe, best Ive seen Great numbers as well...Im only at 262whp 252 ft/lbs SAE dynojet 248C.

 

Yes, I have a G35 6MT sedan. The '05s gained some additional weight too, so there is a few hundred pounds difference depending on what model Z you have. I know my '04 base Z weighed around 3100 pounds. My sedan is 3410 pounds (after I removed the weight). I need those mods and extra power to move that extra weight!

I don't even like to compare peoples times unless they ran at the same track and on the same day. Almost like comparing dyno numbers (they're all different). Even track conditions change by the day. The driver does make the biggest difference of all. My biggest problem is that I can't powershift the 1-2 shift as I lose too much traction and about .3 tenths or more. I feel with a set of slicks I could possibly break into the super low 13s as I am only getting 2.2 to 2.4 60ft times (which yes, sucks but there is no way to make that improve given my current suspension and wheels/tires).

I'm sure a rev-up motored Z ('05 Track or 35th Ann. Edition) with the same mods as mine would be A LOT quicker/faster in the 1/4 mile than me...

I just really like the "shock" factor of the 4 door sedan. No one expects it to hang with or beat more traditional sports/musclecars.

Best of luck with getting into the 12s!

 

LOL, I bet your girls love riding in the "baby hauler."

You know... I hear there's a TT for the sedan

btw, you got anymore pics of the car?

 

Can you post pictures of this mod?

 

Nice writeup.

Can you post pics of the porting you did to the manifold? Thanks!

 

Yes, my oldest is 2 and youngest is 9 months old. They love Daddy's car..heh

About the Twin turbos.... Who has a kit availble? I was thinking one day I'd like to do a supercharger. I dunno if I want to spend $10k on a TT set-up... but might if it could be proven reliable enough not to strand me and the two baby girls..lol

I will take some more current photos tommorow... I run a different grill than pictured and some other stuff.

 

Unfortunately I didn't take any pictures of the lower manifold work or the Crawford plenum. Sorry. I guess if I ever pull the Crawford off I could snap some pictures for you.

 

I will take some tommorow and post them either tommorow evening or tuesday. It's a pretty easy modification, but I don't know how effective it will be for a 350Z. On the G35s, you have to remove the front grill to use the holesaw and flows directly through to the filter. I'm sure you can move the spot where the hole is for the 350Z but that might facilitate removing the front bumper or some other oddball mod.

 

Can you scan and post time slips? Thanks?

 

I thought I read that PE made a TT kit for the sedan, but now I can't find any solid info to confirm that. GurgenPB has a turboed sedan 5AT with a built engine. If you're really interested you might want to pm him and ask what kit he has. I know for sure that Stillen makes a Stage 1, 2, and 3 supercharger for the G35 Sedan (or so its listed on their website). So far Stillen has proven to be very reliable. It doesn't give you the most power among all the other kits, but its proven to be very reliable. Not sure if it applies to all stages, but I know stage 2 comes with a 3yr/36K mile optional warranty. I'm sure you could run in the 12's all day long with the Stillen and more runs on the track. You're not too far away from the 12's...

Btw, is the car lowered at all? It looks pretty mean.

 

[QUOTE=ZXiMan]

I then removed the lower plenum. I used the 36x grit drum to knife edge the intake ports and to remove all casting flaws. I then followed up with the 120 grit flapper and polished all the ports as smooth as a babies a**.

[QUOTE]

This is a bad thing!! The intake ports should NEVER be polished...EVER! They should have a minimum 80 grit rough surface going down into the cylinder head. Port and gasket matching will help performance but polishing intake runners is a huge mistake. This kills the fuel atomization and mixture as it enters the combustion chamber and causes fuel pooling and all kinds of problems associated with a dirty and incomplete combustion process. This includes the entire lower manifold.

 

[QUOTE=g356gear][QUOTE=ZXiMan]

I then removed the lower plenum. I used the 36x grit drum to knife edge the intake ports and to remove all casting flaws. I then followed up with the 120 grit flapper and polished all the ports as smooth as a babies a**.

Only *after* the point of injection....

The correct term for that phenomenon is "reversion" and it is caused by the fuel and air seperating because the fuel sticks to the smooth surface. This leads to a potential lean condition. The polishing work I did was pre-injection point (done before the point of fuel being injected). I know pictures would be worth a million words...

 

I may try to convert a Vortech kit work with my car. I know it has been done.

I've heard too many bad things about the Stillen kit to even consider it. Mainly belt issues.

I have alot of experience with blowers in general. I've had Vortech (Mustang LX 5.0), Magnusson (Lingenfelter C5 Z06) and ATI Procharger ('04 350Z and Dakota R/T). Each design had it's pluses and minuses.

I don't want to have to do too much to get the kit to be reliable....

Yeah, my car is dropped with the Eibach Pro kit as per my first post (I know that was alot of info to absorb in one reading )