Tuning question on built talon

[Novacaine]

First off i have 2 dsm's awd's one is stock engine with bolt on's
buschur fmic
550's vpc/gcc
comso pump
3" exhaust
20g EVO III manifold
Hks standard gate 15lb spring

This setup is very streetable and my daily driver and now to my problem...

1992 tsi awd

Fully built bottem end
arias pistons 8.5 to 1 comp
eagle H beam rods
knife crank
balance shafts removed and balanced rotating assembly
Mild port and polish head
Crower 64414 cams
titanium retainers
Crower springs
Arp bolts throughout
ACT 2900 6 puck
Buschur Fmic
3" exhaust
Turbonetics exhaust manifold w/deltagate 7lb spring
Bushur BR57 turbo 60-1 .63 a/r
vpc/gcc (old style gcc) 660 chip in vpc
680cc inj
BR/SX Fuel Pressure Regulator Kit
cosmo pump

Gauges& instruments
Pocketlogger
Egt
Boost
A/f

ECU mods
TMO 8500 rev limit, no fc

This car is my nemesis..
I have had to reduce fuel pressure to 32psi just to get the car to idle and idle is set to about 1300-1500 rpm due to cams
funny thing is setup is having knock problems even tho the fuel mix is way rich the car is currently ran on pump gas (yea i know just gettin set up first then over to race gas heck im only running 7 psi ya know
Knock counts rise almost imediatly when accelerator is pushed counts reach about 40 anything above 4500rpm and yes that's at 7 psi !
the vpc and gcc are both max reduction at idle and im still way rich even with the fuel press at 32. Is it possible to have knock in a rich state? Egt's are around 1200 WOT till about 4500 then they start rising i let off around 1425F and o2's are .94. I just dont get how the car is knocking so severe. The car is for sure in time and head was only shaved .010 just to clean it up. Any ideas would be greatly appreciated.
Thx

 

[pneumo]

Tunig with a VPC is a bit out of my experience, but I'm wondering what sort of timing you're seeing at WOT? I suspect the timing is too advanced. Hopefully it's not one of those dreaded Phantom knock issues. EGT's and O2 volts are within safe limits.

 

[Novacaine]

yea im afraid that may be my problem timing at WOT is about 20 deg. until knock starts which is very quickly usually before ive got over 1 psi boost ive moved base time from 5 deg to 0 and only change seems to be that car seems more sluggish but the knock remains same. I even changed the "new" knock sensor for another just to make sure that it was ok same deal.. im almost at my wits end ...

 

[T6Rocket]

Not a lot of VPC experience since the 1G MAS is my forte, but I do have one on my Supra.

You car is WAY rich - that will cause knock. You need to lean out the GCC across the board, and the VPC gain - to get closer to .86-.88 mv for pump gas.

Do it in small increments, watching you gauges - also set the FP to stock. Check with Mr. Buschur, since he is the VPC guru for some tips. VPC is known to run rich, and the 680 injectors arent helping, 660's may be better since that is what the chip is.

The GCC is not very sensitive, so dont be afraid to turn the knob - the VPC gain is a lot more sensitive though!

Good luck!
Al

 

[hose101772]

what are your pistons clearenced at?not the problem i'd say,but.i pulled my hair out at first on mine turned out jumping spark with the cheap wires that were on it.also are you running resistor plugs?that can make most modern ignitions go nuts.-by not running them of course.i feel for ya dude-i'm sure most of us here have been in your shoes.

 

[JET]

For all the money that you have stuck in the car, I would seriously recommend getting a wideband. Your O2 readings are useless and the EGT should just be a warning guage. The first thing I would check is to make sure it is a 660cc chip. A 550cc chip would run way rich like that. Also check the intake temp and barometric pressure if you can. They can control the A/F alot. Also make sure you really did get 680cc injectors.

 

[zac83]

Originally posted by T6Rocket

You car is WAY rich - that will cause knock. You need to lean out the GCC across the board, and the VPC gain - to get closer to .86-.88 mv for pump gas.
Al

tell us how rich will cause a knock please?



my recomendations: bite the bullet and go standalone. you checked for a bad knock sensor and is your engine grounded well? i would recomend buying a crapload of jumper wires and jumpering everything to a good ground... ive seen it do wonders before.

hope your problem isnt mechanical, any kind of tapping can be registered as a knock... thoes damn piezo units are really frisky.

 

[Enigma_Man]

If it is phantom knock, I'm sure these guys can help you out:
http://autos.groups.yahoo.com/group/phantomknock/

-Jesse

 

[Novacaine]

Well thx for replys guys i guess its time for me to go wideband O2 hunting hehe by the way where's best place to get those?

 

[RocketBoy]

It seems like you have two options with widebands. You can purchase one that is fully assembled like the FJO ($700ish) or you can look into one of the DIY kits that Techedge sells ($400ish?). I run the FJO wideband and really like it. I have no experience with the DIY kits so i'll let someone else comment.