M35 Mods - Too good to be true?

[cruzad3r]

well i'm not a shrink nor have any training in how to console people but to all those who are experiencing issues with their family, stay tough and best of luck is all i can say. if it's a problem that can solve by money then it's not a real problem. but again everything is about money so what the hell right.

for azeiler - what type of plenum spacer do you have and do you notice any improvement in MPG? how was the install and how much did you paid for the part? where if you still remember the place you bought it from.

thanks - Jake

[atlM35]

That's exactly the setup that I had in mind if I was going to do a custome exhaust. I'm interested to see what the M is capable of with the n/a mods and a tune. We had an issue with our G coupe being loud and raspy with test pipe and true dual exhaust, but other people seemed to like it... but they weren't the ones who were driving it every day

[azeiler]

cruz - at the bottom of the first page of this post i list the costs. labor (remove and install entire exhaust) & ss piping was an additional $1,500, so complete exhaust installed was around $3k. since i have the non-revup motor, i did not use a plenum spacer (also discussed on page 1 of this post). I only had the car 1 day with all the mods, so i don't have any mpg #'s yet. the way i shop for this stuff is by searching online using google shopping and then sort by price; i don't remember who i bought each part from. however, i have an excel spreadsheet with costs on all mods including installation. email me if you want it.

it's so loud now, I can't even imagine that I actually entertained the notion of going with straight pipes. i hope the shop figures out how to get rid of the raspy.

[cruzad3r]

Motordyne MREV2 Plenum & ½” Spacer +20hp - so you didnt do that at all?

[azeiler]

rgb129 5/21/10: "There is some great info on NOT combining the MREV2 and a spacer on this version of the VQ. You should do one or the other not both."

my response: "I think I'll start with the MREV2 and grounding kit."

although i initially thought i wanted to use a spacer when i started this thread, after learning more, i decided not to use one. i guess i could have made that more clear.

[azeiler]

So you don't have to go back to page 1. Can't seem to get the spacing I want, but here's the info.

• DC Headers (ceramic) 464.99
  Berk High Flow Cats (2.5" inlet/outlet) 448.33
  Berk Flex Pipes 55.49
  Magnaflow X-Pipe 83.79
  Vibrant Ultra Quiet Resonators 167.00
  Dynomax VT Mufflers 211.80
  Tips 89.00
  Labor & SS Piping 1,500.00
  Total Exhaust 3,020.40

[mexillis]

no sound clip yet???

[azeiler]

I keep forgetting to put my video camera in the car. But this thing is soooooo f'in loud at WOT, it's unbelievable. Butt dyno says I'm haulling a$$ a lot faster than before. And the transgo shift kit is awsome. I can almost chirp my way through 3rd gear. Holy crap, this thing is fun to drive!! I can't even imagine what an uprev tune is going to do. I'll try to get sound clips this week.

[bbs350z]

op, the vq35 in our m35s are the de version. they dont put out that much hp from boltons. youd be lucky,very lucky to hit 270whp with those bolt ons and a great tune. if you want acceleration try putting in a stock 350z manual diff, its 3.53 and has shorter gearing than the factory 3.3 (i believe the m has?) i did this back to my old auto g35 sedan and it worked great).

also, your measuring crank hp figures. just because a company advertises crank hp, it wont all translate to the wheels.

[EniGmA1987]

Doesnt the M35 (base and sport) have a gear ratio of 3.59? And the AWD version has a 3.69 I think?

[mexillis]

an 06 M35 has a 3.54 gear ratio and for the M45 it's 3.36 from what i found online.

[cjrdriven]

an 06 M35 has a 3.54 gear ratio and for the M45 it's 3.36 from what i found online.

Interesting... I never knew there was a difference in the transmissions at all between the M35 and M45. The M45 would have even been a little quicker if they gave it the same ratio as the M35 then.

[EniGmA1987]

Here is a chart I found online about the gear ratios for the G, the M uses the same ones:






So the M45 has the 3.357 ratio under the 5AT area. The M35 is the 3.538 ratio.

[mexillis]

what vehicle has the 4.083 gear ratio?

[bbs350z]

Baseline Dyno for stock 06 M35. What an experience! He gets the car into 4th gear using the manual shift, lets the rpm's drop to around 2500, then WOT till around 6300 rpm. I can't wait to hear what this sounds like after the new exhaust. I will try to remember to bring my video camera for that.

I forgot that the advertised 280 HP is at the flywheel and didn't realize that so much HP is lost through all the moving parts.




Resonators are on backorder till next week, so exhaust not going in this weekend.

yea im new to the m35x as far as drivetrain goes, but the motor i have a history with from my z's and previous g35. the de generally puts out about 225-240whp the revup about 250whp and the hr about 270+ as ive seen. all depends on dyno used, conditions, etc.

[azeiler]

finally some sound clips. sorry for taking so long but divorce is getting very nasty and depleting $$. so no uprev yet. need to find some tip inserts to help quiet this down. it's getting louder, not quieter, but i still like it. average mpg per the car's electronic thingy is down from 17.1 to 15.2. transmission is performing very nicely and i can occassionally get a chirp going into 3rd.

[youtube]http://www.youtube.com/watch?v=qaDctM1i8SQ[/youtube]

[cruzad3r]

lol - bad mod! if your MPG goes from 17.1 to 15.2

man i used to get 19-20MPG in the summer/fall but now winter i'm getting a lowly 16.5-17.1 which is not cool.

Yes i'm complaining about gas again

[azeiler]

If i were concerned about gas mileage, i wouldn't have done any mods. i am looking for hp.

now i have to adjust the coilovers so i'm not bouncing over every little rock. however, the cornering is awesome. and these tires hold like glue. i finally broke them loose in 2nd gear in a corner and actually drifted through a corner in third, but it took some speed to get these tires loose. god i love this car! once i get the ride smoothened out, it's going to be perfect.

what do you think about the sound? kinda loud, huh?

[cruzad3r]

If i were concerned about gas mileage, i wouldn't have done any mods. i am looking for hp.

proper mod increase efficiency not the other way around. with the right tuning you'll see that.

[azeiler]

Believe me, as soon as the divorce is over & i've saved enough for the tune, it is getting done.

i've never heard of more hp = better mpg. maybe it's the way i drive, but that's the point in increasing hp. i didn't increase hp so i could drive like an old lady just to save gas. i'm not trying to be ignorant, but can you explain how a tune is actually going to improve mpg while increasing hp? maybe it will improve mpg from where i'm at now, but i don't know how it could improve mpg from stock. in the few cars i've built up engines for, i've never seen faster (more hp) = better mpg.

who knows, with all the electronics in cars today, maybe it's possible.

[cruzad3r]

when you throw parts at your car without changing the underlying parameters such as A/F, timing, to name a few then you are not really optimizing those parts. your car's ECU has not optimize to fully appreciate your new parts.

to make this short, with proper tuning, your car will become more efficient which can lead to better MPG. i know my TT does when i chipped it and i'm making more HP at even better MPG. same goes to EVO and STI and these are first hand experience.

if you got time, do a little reading and you'll see what i'm talking about.

[maximaro]

Sorry to update an old post...Just got my 2008 M35x and I'm really interested in your results.

Did you ever get the post modification dyno's done? Also, did you do more than just the exhaust?

Thanks,

[chemjim1]

I agree with Fiveliterbeater's comments. There is absolutely no cheap solution to an additional 60HP (unless you want to go to a supercharger plus other engine mods). The slight HP gains you see posted are only if you drive your car at 5000 rpms plus. Also expect no more than additional 10 rear wheel HP at the rpm range you normally drive in (hardly noticeable). Also, and this may sound like heresy here, dyno results can be massaged (or faked a bit) to give the vehicle owner the results he wants.

Also, if there was a relatively cheap solution to additional HP or fuel economy gains, don't you think Infiniti would have already discovered and implemented it?

[cruzad3r]

Also, if there was a relatively cheap solution to additional HP or fuel economy gains, don't you think Infiniti would have already discovered and implemented it?

you serious?

[chemjim1]

Quite serious. All car makers hire engineers/scientists - many of them really sharp people - to work in their R&D depts to address these very problems. Whatever you have ever dreamed of, they most probably have addressed it in detail, in prototypes, and probably in production. You have to remember that they put their vehicles together to last 100K miles with the general public driving and maintaining them (so they do not break down or over-pollute). This constraint cannot be over emphasized. Example: If they could increase their fuel economy by 1 mpg across their vehicle mix, this would be worth millions to them in the market place.

[cruzad3r]

Quite serious. All car makers hire engineers/scientists - many of them really sharp people - to work in their R&D depts to address these very problems. Whatever you have ever dreamed of, they most probably have addressed it in detail, in prototypes, and probably in production. You have to remember that they put their vehicles together to last 100K miles with the general public driving and maintaining them (so they do not break down or over-pollute). This constraint cannot be over emphasized. Example: If they could increase their fuel economy by 1 mpg across their vehicle mix, this would be worth millions to them in the market place.

sigh!

[azeiler]

Sorry to update an old post...Just got my 2008 M35x and I'm really interested in your results.

Did you ever get the post modification dyno's done? Also, did you do more than just the exhaust?

Thanks,

I have not gotten anything else done yet. My divorce is killing me financially.

Exhaust, plenum and CAI are all hp mods done so far.

[Em35X]

I like those mufflers a lot (well, the tips). I've always wanted slightly larger tips than stock.

Would the sound change a lot if I just changed the mufflers? Because, actually, i LOVE the stock sound.

[mexillis]

Example: If they could increase their fuel economy by 1 mpg across their vehicle mix, this would be worth millions to them in the market place.

[chemjim1]

Yeah, that old guy (Cpt Picard pictured above) would be me, expressing exasperation at the exploits of my younger more impulsive crew. FYI: I am not really interested in modifying my car; I just want it to run and look good. Probably a generational thing. Though the statements I made are more true than you would imagine.