DP installed : No boost spike or creep
 

I nisatlled the DP last night and took the car out for a test drive. Very surprised that the car did not boost above 10 at WOT. No signs of the infamous boost creep either. Exhaust got louder. I was/am disapointed that I don't hear the Turbo Spool everyone told me about after their DP install. Maybe cause my FD is an Auto??.

Anyway, the car pulls harder under WOT. I think it may be "coming off the line" a little quicker. FYI....The DP is a Pettit SS that didn't require stud removal, although I had removed all four thinking the DP would come with SS studs. It mated pretty good with the mid pipe.

I highly recommend that all youz guyz get one installed. Next comes the Bling-Bling!!!

It mated good with the midpipe or the stock cat?

what other mods do you have?

"Usually" you wont experience spiking or creeping if you still have some restriction in the exhaust...like if you still have the stock cat, and/or the stock intake...As long as you have some restriction in the intake/exhaust flow you wont have any issues...However, there are a few exceptions to the rule when you hear of a stock car with DP only hitting 14psi spikes...That would be the exception...But highly unlikely. When I installed my DP the first thing I noticed was that I could hear a tinny sound coming from the DP...I never heard the turbos spool until I got my Apexi intakes. I then changed to the Greddy/Trust Arinx intake which comes with aluminum pipes to replace the stock accordian intake pipes. It was then I really started to hear them spool...I think you hear more from opening up the intake than installing the DP. Glad you like it!

Rated R1: The car has a mid-pipe which is mated to a HKS Super Dragger muff.

dpasseto: The only other engine mod are K&N filters (no stock air box). 17 x 8 Harts w/ Yoko 235/40's all around. Koni adj. coil over shocks. TOTAL wrap around carbon fibre cock pit. Dual pillar pod with autometer sport comp boost and fuel pressure gauges. Lots more to come!!

apneablue: Good advise!. I've got my aluminum intake pipes on order. will probably get them next week. Hopefully then, Ill hear that sweet sound of the Turbo's spooling. I'm just glad i'm not spiking/creeping with my DP to Mide Pipe to HKS set up.

When I installed my downpipe the famous hissing sound dramaticaly rised, I used to hear turbos spool up even when it was comletely stock very litle though.

My brother said driving next to me with windows open "your turbo sounds like a tracktor trailers" joking, but pretty loud when spooling up.

You shouldn't really see boost creep as the stock ECU should hit fuel cut in that case, which is not necessarily a good thing.

You might experience boost spikes if/when you modify your intake.

Mahjik: Intake is modified except for hard pipe kit.

Spikes usually occur during the transition over to the secondary boost. Try the boost test:

http://www.scuderiaciriani.com/rx7/boost_test.html

If you can't maintain at least 8 PSI to redline, i.e. the car losses all power in the upper rpms, you are probably hitting fuel cut.

Ok, just to make sure I'm following this.....you're running d/p, m/p, c/b and intake on a stock ecu?

GoodfellaFD3S: On the nosey !!

Wow, stock ecu? hmmmm, brave man indeed. :)

The car's not boosting above 10, so why should I upgrade the ECU?

Because if you are hitting fuel cut, it's not a good thing. Fuel cut will keep you from going over (or a little over) 10 PSI as long as it's not a spike. However, that means if you are hitting fuel cut, you'll lose power every time you floor it and it kicks in.

Mahjik: Well under your scenerio, everyone boosting 10 psi would need to upgrade their ECU because of possible fuel cut via stock ECU?? Not trying to argue but my "newb" ignorance causes me to ask these questions. Thanks for your help!!

Well, here's the problem:

*IF* your car is boosting more than 10 PSI, the stock ECU will do it's best to keep it at stock levels. However, the ECU cannot react fast enough (or isn't designed to react fast enough) to stop boost spikes.

So, let's say you start going past the stock maps at around 5000 rpms, the stock ECU enables fuel cut to keep you from going to far which basically feels like you lost all power and it's time to shift... Now you can never redline past 5000 rpms until you upgrade the ECU as you'll always hit fuel cut. You might not hit 14 PSI, but your power will be cut short right in the middle of having fun.

Now, if you aren't getting fuel cut, then there isn't a problem.

Mahjik: Makes perfect sense!! I think (for now) I'll be okay. The car revs up into the red pretty quick without any hesitation. Pulls very strong without losing acceleration.

Only problem is that it doesn't climb too fast or gain substantial Boost above 8 after transition (above 4500 rpm). I guess it can't always be perfect. Thanks to you and all who participated.