Does anyone else here think that most of the Maxima turbo setups are a bit overkill? It just seems like most people want a dyno/highway queen Maxima instead of a more street useable turbo. I see these awesome turbo Maxima posts and notice the cars are running massive intercoolers and relatively large turbos. The owners constantly bicker about how they have no traction once boost hits in the lower gears. Wouldn't it just be easier to run a smaller and quicker spooling turbo ultimately sacfricing some power for more broad and useable power characteristics? Most turbo Maximas seem to easily out power their chassis. Huge power is always cool, but not being able to use it efficently seems kind of pointless.

I guess I've always been the odd man out when it comes to power. I'd prefer a small quick spooling turbo that gives me nearly instant boost, excellent low rpm torque, and overall good driveability. The lower boost would be less stress full to the VQ overall, fewer parts would break, piping would have less chance to pop off under boost, fuel consumption would be lower, and most importantly, I'd think this setup would perform better in all types of racing (road and 1/4 mile). It would lack the sheer HP numbers and above 100mph acceleration, but how often do you use that? I'd also run a small IC (300ZX TT IC?) in the area where driver's side fog light resides.

Anyone else think like I do? (doubtful..... )


Dave (the guy that really doesn't care about FMICs and big turbos)

 

To me, a larger turbo is more feasible because you will not have any traction in the lower gears with a quicker spooling turbo. At this moment, even with the T4 ball-bearing, in 1st, 2nd, and some of third, I have NO TRACTION whatsoever.

So in my opinion, the larger turbo gives you time to get going before the boost fully kicks in, and when it does, watch out lol. A smaller turbo does reach full boost faster (in most cases), but I need the traction to at least get moving....

 

That's why I will run a smallish Z31 T3. A ball bearing T3/T4 would be nice. Costs a small fortune though.

 

If I were to build a turbo setup, I'd also be more interested in quick response than highest overall power.

I saw a turbo RSX this weekend thathad this problem to the extreme. It went like this:

BRRRRRRR...WHOOOOOOOOSH
<shift>
BRRRRRRR...WHOOOOOOOOSH
<shift>
BRRRRRRR...WHOOOOOOOOSH



I want:
whoooooosh!
<shift>
whooosh!

 

I also think more usuable power would be nice. I think along the same lines Dave.....question is, how would traction be? Thats the main concern I would have.

 

All I know is, my V1 S/C is really great and all, but I do have some beefs. Although I am in love with the noise it makes, and the power near redline, I could really use more low end power (~2300rpm) for passing. For instance, if i'm in the left lane, just creeping along in second gear, and I see a huge opening in the right lane, i'll switch over and floor it. Ive done this and the s/c was soo laggy that the caprice behind me almost nailed me since it took so long for my boost to spool.

Some power to get up and go would be nice especially in those situations.

 

T3/T4 can't go wrong IMHO.

3inch exhaust is a MUST

3 inch downpipe wiould help as well

and a GOOD flowing up-pipe to the turbo and boost comes VERY fast

 

I agree with you Dave.
Being constantly spooled is nice. Being able to have full boost almost instantly in 5th gear cruising on the interstate, is nice.

Everyone who talks about traction being so bad with smaller turbos, I strongly disagree. large turbo boost hits fairly quickly at the higher rpm range..

take for an example: my car makes full boost before 3000rpm

-If I floor it from 2500rpm in 1st gear, the car does not loose traction all the way to redline.

-If i floor it from 4000rpm in 1st gear, it loses traction.

So having the full boost at low rpm makes the horsepower climb like a regular curve instead of a mountain coming up in the peak band of the car causing traction issues.


dyno queens, etc do have a special place in my heart though.

 

Is there a turbo as loud/almost as loud as the V1 supercharger at idle? Is there any turbo louder at WOT? What is the best sounding turbo in your opinion(s)?

 

no, nothing that will compare at idle. (unless it's spooling down)


Yes they are louder at WOT... and best sounding? not sure they dont vary that much but I have been told by many people T3 exhaust is one of the louder ones... but dont get me started on how loud the T106's and stuff are.

 

What about Nigels kit? I remember that vid he put out when he first got the turbo. It went to a clip of his engine bay and it was EXTREMELY loud, as loud as the V1. It didnt have a crickety sound, but sounded like a jet engine at idle. What was the deal with that?

 

I don't know if I am familiar with what video you are talking about? unless you are talking about UncleMax's car at the gas station idling.. and its not makin any noise other than those fans and loud exhaust (well, downpipe)

But speaking from my personal experience with quite a few turbo cars, turbo's dont make much noise just sitting there, unless you are coming off a run and it's spooling down. At idle there is most likely not enough flow to make it do anything, even flooring it in neutral I can't make any positive boost. And I would guess this goes for most turbos, every turbo car I can think of doesnt make any turbo-whining noise just sitting idling, and yes you got me started on the 106 now, my friends mustang is rather quiet at idle(talking about turbo noise) even with a 106.

maybe if you put a TINY turbo on our car it would make noise bc it would be spooling at idle? but i mean ...... haha

 

Well, the SC makes no boost at idle either, but it still emits a crazy scream, becuase of the blades inside it cut at an angle. I guess Turbo's and Centrifugel (vortech mainly) S/C's share no simularities internally?

The video i'm talking about starts out inside Nigels car ( a few passengers) He accelerates and some one laughs in a kind of sedistic way. Then the next clip is of the hood open and video'ing his setup. It shreeks, and is very distinct.

 

SC is also directly tied to the belts so it is "spooled" to some extint whereas a turbo is pretty much letting the air pass through at idle.. I dont really know any other way to say but yes v1 makes plenty of noise at idle I realize, and love!

i do know the vid you are talking about, and the only thing I can guess is that is just how the camera captured the noise etc? I cant speak for sure about his car as I have never seen it, but like I said from my personal experience.

you would never know or guess my car is turbo sitting next to me at a redlight, and I have only a downpipe to behind my front tire.

 

Yup, the V1 is addicting. Give it a little revv and the crickets unite in a nice high pitched howl/whine. What about Turbos? At what point do they become audible? Like, can you sit at a stoplight, revv up to 2000 real quick, and have the turbo be heard?

 

yes but it doesnt sound as pretty like when you are driving.. turbo really needs to be under strain.. I wish I could capture the sound of turbo but my little digital camera I take my vid's with I guess doesnt pick up that high or something?

regardless, here is one attempted vid (0.3mb) where i tried to pick up the sound of me cruising - you can see the low rpm and low throttle, but still coming into ~4psi or something and making plenty of noise haha spool up spool down

 

Damn, I'm surprised you agree with me seeing that your Maxima is truely a high powered beast with huge topend.

You're thinking exactly like me, a smaller turbo would spool quicker and would be far more responsive to smaller throttle inputs. The reason people have traction problems is because when the boost of the larger turbo comes online, the increased power over a small amount of rpm overwhelms the tires. With a smaller turbo, the power is applied earlier and in a far more linear fashion therefore it reduces the chances of the tires being overwhelmed. I guess a good example would be the characteristics of VWs 1.8Ts. It's very hard to tell that those cars are turboed.

Getting off the line with a quick spooling turbo V6 VQ would be like driving a VQ with serious low rpm torque therefore you wouldn't have to come off the line at huge rpms nor fear of bogging and then hitting boost which sends the tires into a frenzy. Imagine how easy it would be to control the VQ in the autocross?

I'd estimate the power would only be around 230-245fwhp and 260fwtq, but the curves would be thick with power. I'd also think the plumbing might be a slightly easier. What kind of turbo would be good for this type of application?

Oh well, it's just a pipe dream for me


Dave

 

I believe that was MadMax95 emiting the chuckle, lol, him or Dafro, but we were the ones in the car. It was only at 4psi boost then I believe???


I do remember what you are talking about but I dont think it is that loud really, just the microphone picked up on it alot. Last time I heard/rode in his car he had 10lbs of boost with the new turbo and it wasnt that at idle, but with boosting, you could hear it.

 

That sounds cool, like wooshing wind. The V1 is really loud until about 2200rpm, then it gets REALLY quiet. That turbo of yours is actually louder. The only thing I get at WOT is a jet engine like whine, but its really quiet. The sound of a n/a Max with a pop charger sounds much more aggressive.

I guess the only type of boost is really loud at WOT is a roots type supercharger.

 

and turbo.

 

Dave, one huge thing to consider is piping construction. At this point I don't think bolting even a tiny turbo my setup would reduce my lag.. although it is very responsive and virtually innoticeable lag in my car - the holding back factor I would say is the length of pipe run to the turbo. By locating the turbo even closer to the manifolds you dont have that "pressure chamber" or whatever effect that piping is giving... But I wouldn't see any reason for going smaller than t3/t4, considering I read positive pressure at the intake manifold at 2000rpm..

 

You serious? All the videos i've seen, they dont appear to be *that* loud. Maybe its becuase all that damn backround music. I want to find a Turbo vid without any music, just straight acceleration clips, from another cars perspective especially. Hlh, you make a turbo that sounds like a cobra eaton roots type, and you will be my turbo god.

 

Haha, good one.

 

People hear my turbo coming WAY before they hear me, sounds nothing like the roots s/c though.

 

Plan on making any future vids with a different camera? A good one would be, give your friend the video camera, and have him stand outside shooting you do various driveby's. Then do a car-to-car clip, and finally an interior clip. Your turbo comp I and II vids are sweet-@ss, but theres too much "riff raff" to hear your car. Its hard to see the nite vids too.

Have you seen that vid of the 600whp Cobra with the ear peircing s/c? You need that camcorder!

 

I'd say the OEM turbo from a VG30DET or VQ30DET should fit the bill. Both engines make around 280bhp stock, so you know the turbo can make more power, plus it should have excellent response since they are ceramic. However given that they are ceramic, that means they won't last as long as other turbo's at very high boost.

 

Yeah show us some more vids with more emphasis on the sound of the turbo and then i guess we can all decide. Personally i love the sound of a turbo car as its coming down the road. The evo 8 def. is noticable when driving towards or past you.

 

Craig, I think you are a little misinformed. Most of the noise you hear from a V1 is from the drive gears. You can hear air flowing, too.

The SC does indeed pump a lot of air at idle, more than the engine can use, so technically it is making boost. You don't see it at the boost gauge because the throttle is closed and manifold vacuum is high, keeping the bov open and releasing all the air that the SC is pumping. If you put a boost gauge at the blower outlet you would see positive pressure at idle.

Also, a centrifugal compressor like our beloved V1 is identical to a turbocharger compressor. The only difference between a V1 or V2 (aside from the gear drive mechanism) and a turbo compressor sized well for the Maxima is that the Vortech blowers are huge in comparison. Too big, if you ask me, but they certainly do not run out of breath at high rpm.

 

If that's true, why does the Vortech rate the critical max speed for the blower at ~50Krpm, when the turbos easily operate at 100K+rpm?

 

100k+rpms!!! Thats awesome. Anyone know what the max speed is for a T4?

 

Probably due to the step up gearing. Gears don't like really high speeds. If the blower spun freely it could go much higher.

Clearance between the blades and the housing might be another issue. The clearances might have been made a lot tighter with a speed limit in mind.

But the basic shape of the housing and the compressor wheel is the same as what are used in turbo compressors.

 

Gotcha...thanks!

 

Not sure if these are max speeds, but:
http://www.turbofast.com.au/FlowTO4E.html


Also, some of the upcoming turbos reach speeds approaching 200Krpm!

 

I just have a quick question, and I dont mean to deviate from the topic but, are you guys running stock compression ratios on your turbo max.

 

Most are running stock internals.

 

Honestly, I think that any decent turbo setup is going to overwhelm the tires. On Jason Sadler's car, we used a T3/T04E hybrid, typically a turbo used on Hondas. Power delivery is very linear and very early. But there is simply too much torque down low for the tires to handle. The car puts down 256 whp at 5 psi with 254 ft./lbs torque (around your estimates), very good for only 5 psi, but far lower than some other turbo Maximas here. However, there is 240 ft./lbs of torque available by 3000 rpm and full boost is reached a little before 3000 rpm. If he digs into the throttle from a roll, car spins. If he floors it off the line, the tires spin, anything he does aggressively in 1-3 gears causes a lot of wheelspin. If he nails it in first and shifts hard to second, the torque steer will cause the car to literally switch lanes if he's not careful. And that's with only 256 whp. When he turns up the boost and is making the 300+whp we anticipate, things will only get worse.

There is just too much torque for a FWD car to handle. The bigger T4 turbos some of the guys run have the same problem only in a different way. Boost hits later, but when it hits, it hits harder.

On a VW 1.8T, the turbos spool very quickly, but those cars don't make nearly the torque our VQ's do. My friend has an Audi A4 1.8T w/ an upgraded turbo setup, and his car feels very nice. Power delivery starts low and is very linear, but there is simply less power to handle.

 

jeff-

Drag Radials is the answer

And baby it off the line and hammer down and shift quick.

We can get the power to the ground...

I am sure jason can with the 50lb weights he calls rims ..

go with a 245/35z18or19 and slap some BF drag radials on there and I am SURE he will hook up.

 

Yeah, but this is jason we're talking about. When's the last time his car saw anything smaller than a 19" rim?

He does baby it off the line, it's when he hammers it that things get interesting. And he's one of the slowest shifters I've ever seen

 

Well grandma will have to learn.. BTW.. You have a PM

 

If you've ever been in a boosted 5th gen you would see the torque steer isn't nearly as bad in those cars. Almost no torque steer if the tires pressure is just right. Unequal length drive axles OWnZ tEh 4th gens.