This is for a built bottom end. I know most of you built guys also have upgraded heads and valvetrain. However, what would be considered the safest highest RPM I can rev too with stock VQ35DE heads and valvetrain before running into issues such as valvefloat (I was thinking 7500 is where things start getting a little iffy, but I wanna hear it from you more experienced guys).

I have a built short block: Wiseco pistons, eagles, acl bearings, rev up oil pump. Currently only have my shiftpoints (auto) set to just below 6k, when I manually shift and take it higher such as to 6.4-6.5rpm I can feel there is still lots of power coming in uptop, just dont know how high to change my shiftpoints too.

Any input will be appreciated...

 

According to JWT, they recommend upgraded valve springs for their cams above 7k rpms. So I would say that is where you may want to set the limit.

 

Ok, that sounds good then. I am really missing out on some power by shifting so low at 6k.

 

Where do you make peak hp? What kit?

On the extreme side of things I know of a car who revs to 8000rpms 100% stock valvetrain @ 600+whp, no issues in 10K+ miles with racing. Im not condoning that just throwing it out there.

From what Ive seen out of most kits/builds, Id rev to 7000-7200rpm's -depending on the peak. Not many people would properly need to rev or use 8000rpm's in these cars.

 

Alberto, I made my own kit, single turbo with an HX40 Holset. Considering I have stock cams, and a FWD intake manifold, I dont think i'll have much benefit in going all the way to 8k(iv never compared dyno curves between a rwd and fwd manifolds), but knowing what you just mentioned tells me that, like you said low 7k should be my peak. I have yet to dyno, however this turbo takes a little bit to spool up so all my power and torque is most likely shifted to the right vs. a smaller quicker spooling turbo.

 

Oh thats very cool.

Only way to know for sure is dyno, and shift after the peak, never before or at the peak. Without knowing 7000rpm's is a safe bet.

 

Thanx alot for your input, ill stick to max 7k rpm.

 

pix of your custom single?

 

Well rather not get flamed as usual when posting out of the ordinary stuff(some peeps cant think outside the box lol), but its a rear mounted turbo setup and its on a 97 Maxima. still want the pics? lol

 

Def post the pics, fawk any haters they will be dealt with in usual fashion

 

lol, here we go then:

 

Its not a clean job as you can see there are zip ties supporting some part of the charge pipe, but I did this all in my front yard with basic tools, minimal funds, no welder, no pipe bending machine, nothing lol. just heater hoses that had the needed bends, and 30 bucks worth of piping from local muffler shop. Only needed welding on the turbo to mount it to the catback (where muffler used to be).

Eventually i'll upgrade the piping for some mandrel bent aluminum pipes (lighter weight too vs. the damn steel ****). But so far, its been successful in the 3-4 years I have had it, the first rear mount turbo maxima, ever! lol

Ypipe and catback is all wrapped, so it spools almost as if it was a front mount, actually my original turbo was given to me by another turbo maxima owner which had traditional front mount setup, and the turbo on my setup spooled basically as early as it did on his, so that shut up a good amount of people yapping away about how RMT will have huge lag and bla bla bla lol.

 

Thats pretty sick for a DIY yard job. Arent you worried about that filter being exposed? Why not encase it?

Ever run it at the track?

 

Thanx man, its been a cool neverending project lol, there is always something to improve on it, and I see it as a major accomplishment, considering its the first and only car I have ever owned (since I started college in 2001), from not even knowing cars needed oil changes(i was that ignorant) to building my own engine and turbo kit, as well as tuning it myself, no mechanic or tuner has ever touched my car lol.

Well K&N sells these covers that you put on them to further protect from road debris n stuff, but I have not yet to do so, and I am worried about the restriction it would provide. In the 3 years of daily driving everywhere in Miami, through hard rain, over sand, dirt, everything, never an issue. So far oil analysis dont show any contamination from bad filtering either, but eventually i'll improve that.

well only took it to the 1/4 when I first put the turbo on, that was on the stock VQ30 motor, but wasnt very impressive at high 13's with 105 traps, was making about 280hp back then. 60' always kills me since I dont have a high stall converter. I did do more 1/8 runs though at 312whp still with the 3.0, and that got me 8.6 @ 82 on average, with 2.0 60'

 

stock DE cams peak about 6200rpm.....power falls like a cliff above that.

There is also a fair amount of valve float above 7k rpm (due to springs) so definately gonna give up some up there. I ran mine up to 7200rpm with stock valvetrain only at the track pretty much to avoid shifting into 5th.

Tom

 

nice job streetz, hope to see this ride sometime out on the open road. U ever go down by us27 n okeechobee? Good way to test out ur ride

 

Thanx Thom00...

I think what I am going to do is program my shiftpoint to about 6500 rpm, so when it gets into the next gear its not too far down in the range. Now that I know to keep it below 7K I got some room to play with, anything is better than my current shifts at barely 6k, I'll know better once I dyno. Thanx for the input.


Nah im deeper south but my mustang buddies always telling me to go out there to teach the stangs how its done lol. Not so excited about street runs though lol, im a ***** when it comes to that, unless I am tuning at 3 AM in complete silent and empty highway lol

 

lol its all good bro. Either way the DIY work is awesome. Congratz, im sure itll be all worth it once its running n tuned right!

 

if ur on stock cams then u arent gonna keep making power up top..i would go to 6500..but only way of knowing is a dyno

 

sweet!! thanks for the pix! i always love custom jobs!