that depends on the vac that the engine creates. -22 on my stock block. i'm -13 on my build engine. build engines don't create as much vac.

 

I would think that would depend more on the compression, cams and displacement more than the fact that it's a built engine ( Forged rods and pistons shouldn't change vacuum just because they are forged ).

 

that's why i said built ENGINE and not built block.

i have ported heads and cams

and actually a built block would change it if you have low compression pistons.

 

thats weird you only have -13. no one else has that little vaccuum with bigger cams and head work (like the SP car or Hals car....)

 

straight from the haltech. it's high -13 and sometimes into -14. I'm idling at 1100 if that makes any difference also.

also it's the same on the gauge that i used for stock block at -22 at idle.

idk, hal didn't think it was abnormal.

 

ohh ok, ya an idle that high explains it. Do you need it that high?

 

It still has a slight issue of rpms dipping on decel (clutch pressed in). It was really rough when hal was tuning (dropping 300 or so rpms) so he set it that high. now that it's cleared up after the tune it drops only about 100 rpms so he will probably lower it down to 900/1000 rpms this tune. Could also have had somethign to do with the drag from the super charger (and definitely has to do with my twin disk clutch being so light).

This engine just isn't happen idling anywhere below 900.

 

weird, my flywheel is 11lbs and had the SC as well. well i guess as long as you dont have any leaks and it runs well

 

ya, i was puting down a perfectly linear boost curve all the way to 14.5psi at redline. no leaks. Piping leak shouldn't affect my vac at idle though

These heads are ported like crazy. Compared to my stock head intake and exahust ports it's night and day difference.

 

I still can't get to 14psi Binder!

Hey is that head work make any noticeable difference. I love built head but as I understand these heads flow very well out of the box. Just wondering if perhaps you losing power over porting the heads slowing the air velocity thus decreasing TQ.

Can our SC take advantage of a nice port job on the exhaust runners or perhaps oversized exhaust valves? Wish I had.

 

hmm, werid you can't get to 14psi. check the boost curve and see if it flattens out from slip or leak.

my tq might have taken a little hit on the s/c but now since i'm running a single turbo i'm glad i have headwork. It'll be nice for the engine and will give more flow to my turbo.

 

guys, i just got Haltech, but i couldn't find a base map for 350z on the resource CD.. shouldn't there be one?

oh, and i need an answer to this as well.. since i was running Osiris, my MAF maxed out @ 5k rpm.. since i'm switching to Haltech, do i still need to install the HPX MAF?

 

idk where a base map is. we installed mine at injected so hal tuned me straight from there. he'll email you one if you need one.

you do not need the hpx maf but you do need at least a stock maf.

 

Really? Why? I thought the stand alone unit was solely map/tps based.

 

Thanks binder.

stock MAF is still on the car, but i did buy the HPX MAF.. i think i need to sell this now.

but how is the tuner going to tune it with stock MAF maxing out? i can't understand the logic behind this. can anyone elaborate please?

thanks!

 

It will be tund with the MAP (comes onbord with the Haltech) and leave the stock MAF just to get the air temp reading. (you can run the car without the MAF, you just need to get the temp sensor).

 

Ahhh!

thanks for clarifying that.!

 

Racing Bypass valve?

the 9psi one.

Is this a necessity going TTrim or higher boost. The stock bypass is set to about 6psi. I would assume if the door is shut until 9psi, then response times and possibly boost pressure would increase over all.

has only made this upgrade?

thoughts on doing so?

Also the intercooler, worth the upgrade?

 

racing bypass will not increase boost levels or building of boost. all the racing bypass does is increase the amount of boost that can pass through it which is needed when running higher boost levels. If you have a small bypass valve and are at 17psi then let off hte throttle the air can't escape fast enough which could cause surge.

you adjust when they close based on vacuum. my bypass was adjusted to close about -4mm hg. Once it's closed it does nothing else. Boost is built solely based on engine rpm and pulley size.

i was running 14.5psi with no issues with the regular blowoff.

for intercooler, i would definitely upgrade. At 14.5psi my intake temps would skyrocket to 180* after a few pulls. Just a single drag run would only get me to the 160's but i would have to let it cool. Also if you can upgrade the piping then that would help also.

 

Im doing my install this weekend I have a V3 SC I plan on using the 3.12 pulley.My tuner kit came with belt K060795.What's the correct belt to use k0607085 k060790 or
k0607095? If I have to get the GTM pulley mod I will do so but I just want to get the kit on cause I am heading down to R/T tuning for a tune next friday.