Greddy Profec B Spec I (old model) Install...NO Boost Spikes..(Tip) Gear Hunting Eliminated.........
10-17-2004, 12:22 AM
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Greddy Profec B Spec I (old model) Install...NO Boost Spikes..(Tip) Gear Hunting Eliminated.........
Finally got around to installing the Greddy Profec B Spec I on my S4. I already had one installed on my Porsche 951 - the same model. I know what the Profec B did for my Porsche, so I was expecting similar results on the S4.
Well, my expectations were exceeded after installing the Profec B on the S4. First, I TOTALLY eliminated the N75 (it's still attached to ECU electronically, so I don't throw a CEL) and have the Profec B controlling Boost & the Wastegate.
The install was much simpler than I expected. I put the Stepper motor in the engine bay near the pollen filter (for those who know where its located), that's the coolest part of the bay. I cut a hole in the plastic box that holds the ECU and ran the vacum line (from the manifold) and electric lines (from the stepper motor) to the Profec B solenoid/brain inside the passenger compartment (where I mounted the solenoid/brain) below the steering wheel and above the brake pedal.
I connected the positive electrical wire from the solenoid/brain to the 75x terminal (behind the bottom part of the dash - below the steering wheel) and the negative to a screw on the fuse box (similar to what u would do when installing an AWE or APR boost gauge). That directed power to the Profec B solenoid/brain only when the ignition was on.
I then swapped the wastegate and turbo lines from the N75 to the Profec B stepper motor. I used diagrams from the Greddy website, and the enclosed instruction booklet. This is a simple process. Greddy also provides vacum lines that are as good as OEM, if not better. The only downside, they did not provide hose clamps, they include those black tie-straps. Do yourself a favor - go to Pep (PEB?) Boys - get yourself better (metal) hose clamps - I did.
I was not able to do any test runs immediately (last weekend), so I left the boost (lo, hi) and wastegate ***** at their lowest settings (this past week). Yesterday (Sat), I finally got the opportunity to do some HARD runs (at a local high school parking lot - it's huge). Since I have not installed my O.ct boost gauge (my next project), I also bought a cheap ($15) boost gauge from Pep (PEB) Boys.
I plumbed the boost gauge into the vacum line that routed into the back of the Profec B solenoid/brain. Thus, both the Profec B and the boost guage were sharing the same vacum line. At this point, I started my runs testing both 'lo' and 'hi' boost settings.
I started by adjusting the wastegate (sensitivity) **** clockwise. I finally settled on the 1PM postion. The wastegate seemed to respond best between the 12 and 2 o'clock position for both 'lo' and 'hi' boost on my S4 set-up (see sig for my goodies). My vacum reading at idle was -9 psi (zero = atmosphere). My first first three runs were to set 'lo' boost. I finally settled on 9 psi (max) which kicked in exactly @ 3k rpm and tapered to 7.5 psi @ 5k rpm. My second three runs were to set 'hi' boost. I finally settled on 13 psi (max) which kicked in @ 3k+ rpm (but less than 4k rpm) and tapered to 11.5 psi @ 5k rpm.
The only downside of these hard runs - SMOKING ROTORS - I mean SMOKING! I am sure that I probably warped the rotors from excessive heat, but it's cheaper than BLOWN turbos (been there, done that - when the car was stock - a story for another day - but its already been shared with this forum).
Like I said in the 'subject line', I have absolutely NO boost spikes with the Profec B replacing the N75. Another unexpected benefit - NO GEAR HUNTING! When I go WOT in Tip mode, the tranny drops from 5th gear to 4th, and STAYS THERE! No more of that 5th to 4th rapid shifts.
Also, power (GIAC-X) is much smoother throughout the band - I can increase power (moderately depressing the accelerator) in Drive mode (5th in Tip mode) without the car surging (boost spike) - it just keeps applying power - with NO surge (or hesitation).
I HIGHLY RECOMMEND that anyone driving a Tip with a GIAC-X, or any other higher than avg (boost) S4 chip, replace (TOTALLY - DON'T operate "in-parallel" w/N75) the N75 with an EBC (electric boost controller). The final upside of an EBC, it holds boost, rock solid - MBC have a tendacy to have boost creep over time. After installing the EBC, I also found that my Stratmosphere DVs were a POS (I cleaned them regularly), I replaced them with 710Ns, the difference was NIGHT & DAY. From now on, only 710Ns. Plus, they are only 1/2 the cost!
Didn't take any digital pics of my install - but I can - for those who are interested.
My S4 HAS NO NEED FOR THE N75 - ever!
NOTE: The Profec B Spec I does NOT use fuzzy logic to learn boost curves, etc. It's strictly driver controlled. I've never used the Spec II, so I can't comment - but I have heard some unflattering things. Profec B Spec I's are becoming a RARE breed with PREMIUM prices being charged, if u can find one. The one for my S4 ( I bought the one for my Porsche 2 yrs ago) cost $299 (plus shipping). I bought it from a "ricer" shop (Supras are their specialty), but I didn't care. For those who question spending more than $50 for a boost controller, let's look at it this way. You spent anywhere from $20k - $40k for your S4; now you complain about spending more than $50 to PROTECT your MODIFIED investment - pul-leeeeze!
Well, my expectations were exceeded after installing the Profec B on the S4. First, I TOTALLY eliminated the N75 (it's still attached to ECU electronically, so I don't throw a CEL) and have the Profec B controlling Boost & the Wastegate.
The install was much simpler than I expected. I put the Stepper motor in the engine bay near the pollen filter (for those who know where its located), that's the coolest part of the bay. I cut a hole in the plastic box that holds the ECU and ran the vacum line (from the manifold) and electric lines (from the stepper motor) to the Profec B solenoid/brain inside the passenger compartment (where I mounted the solenoid/brain) below the steering wheel and above the brake pedal.
I connected the positive electrical wire from the solenoid/brain to the 75x terminal (behind the bottom part of the dash - below the steering wheel) and the negative to a screw on the fuse box (similar to what u would do when installing an AWE or APR boost gauge). That directed power to the Profec B solenoid/brain only when the ignition was on.
I then swapped the wastegate and turbo lines from the N75 to the Profec B stepper motor. I used diagrams from the Greddy website, and the enclosed instruction booklet. This is a simple process. Greddy also provides vacum lines that are as good as OEM, if not better. The only downside, they did not provide hose clamps, they include those black tie-straps. Do yourself a favor - go to Pep (PEB?) Boys - get yourself better (metal) hose clamps - I did.
I was not able to do any test runs immediately (last weekend), so I left the boost (lo, hi) and wastegate ***** at their lowest settings (this past week). Yesterday (Sat), I finally got the opportunity to do some HARD runs (at a local high school parking lot - it's huge). Since I have not installed my O.ct boost gauge (my next project), I also bought a cheap ($15) boost gauge from Pep (PEB) Boys.
I plumbed the boost gauge into the vacum line that routed into the back of the Profec B solenoid/brain. Thus, both the Profec B and the boost guage were sharing the same vacum line. At this point, I started my runs testing both 'lo' and 'hi' boost settings.
I started by adjusting the wastegate (sensitivity) **** clockwise. I finally settled on the 1PM postion. The wastegate seemed to respond best between the 12 and 2 o'clock position for both 'lo' and 'hi' boost on my S4 set-up (see sig for my goodies). My vacum reading at idle was -9 psi (zero = atmosphere). My first first three runs were to set 'lo' boost. I finally settled on 9 psi (max) which kicked in exactly @ 3k rpm and tapered to 7.5 psi @ 5k rpm. My second three runs were to set 'hi' boost. I finally settled on 13 psi (max) which kicked in @ 3k+ rpm (but less than 4k rpm) and tapered to 11.5 psi @ 5k rpm.
The only downside of these hard runs - SMOKING ROTORS - I mean SMOKING! I am sure that I probably warped the rotors from excessive heat, but it's cheaper than BLOWN turbos (been there, done that - when the car was stock - a story for another day - but its already been shared with this forum).
Like I said in the 'subject line', I have absolutely NO boost spikes with the Profec B replacing the N75. Another unexpected benefit - NO GEAR HUNTING! When I go WOT in Tip mode, the tranny drops from 5th gear to 4th, and STAYS THERE! No more of that 5th to 4th rapid shifts.
Also, power (GIAC-X) is much smoother throughout the band - I can increase power (moderately depressing the accelerator) in Drive mode (5th in Tip mode) without the car surging (boost spike) - it just keeps applying power - with NO surge (or hesitation).
I HIGHLY RECOMMEND that anyone driving a Tip with a GIAC-X, or any other higher than avg (boost) S4 chip, replace (TOTALLY - DON'T operate "in-parallel" w/N75) the N75 with an EBC (electric boost controller). The final upside of an EBC, it holds boost, rock solid - MBC have a tendacy to have boost creep over time. After installing the EBC, I also found that my Stratmosphere DVs were a POS (I cleaned them regularly), I replaced them with 710Ns, the difference was NIGHT & DAY. From now on, only 710Ns. Plus, they are only 1/2 the cost!
Didn't take any digital pics of my install - but I can - for those who are interested.
My S4 HAS NO NEED FOR THE N75 - ever!
NOTE: The Profec B Spec I does NOT use fuzzy logic to learn boost curves, etc. It's strictly driver controlled. I've never used the Spec II, so I can't comment - but I have heard some unflattering things. Profec B Spec I's are becoming a RARE breed with PREMIUM prices being charged, if u can find one. The one for my S4 ( I bought the one for my Porsche 2 yrs ago) cost $299 (plus shipping). I bought it from a "ricer" shop (Supras are their specialty), but I didn't care. For those who question spending more than $50 for a boost controller, let's look at it this way. You spent anywhere from $20k - $40k for your S4; now you complain about spending more than $50 to PROTECT your MODIFIED investment - pul-leeeeze!
10-17-2004, 01:18 AM
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Excellent post!
I've been considering an EBC for my setup, The Profec B seems to be a great unit, only that it doesn't accurately control boost over 23#, according to what I've heard :/ I wonder if the smoothness you experience will degrade the higher you go.
I'm currently messing with N75 tinkering, if that doesn't meet with my satisfaction, I'll explore the limits of the Profec B.
I'm currently messing with N75 tinkering, if that doesn't meet with my satisfaction, I'll explore the limits of the Profec B.
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10-17-2004, 02:17 PM
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Cautious....I Blew The Passenger Side Turbo When The Car Was Stock - Just Out Of Warranty - AOA...
split the difference 50/50. The turbo blew at 52k mi.
AOA replaced both turbos (KO3s) and ICs with updated parts (my car is a 11/99 build date). No, they wouldn't replace them with KO4s. Believe me, I tried to get AOA to go 50/50 on KO4s. They would have none of it. I din't start chipping and making all the mods that I currently have until 75k mi..I'm currently @ 82k mi.
To answer your ? - I'm just cautious - the next set of turbos will be 100% on me. WIth a kid in college, the budget can't afford KO4s right now. I'm surprised that I was able to get the mods that I currently have - after paying these sky-rocketing college tuition bills.
I'll probably up the boost as time goes by.
The major differences btw the Profec B and the MBC (in parallel) set-up are as follows:
The Profec B is controlling my boost THORUGHOUT the power curve - I'm not deferring low end boost control to the N75.
The Profec B ALSO allows me to DIRECTLY control the wastegate - the N75 does NOT give you that ability.
The Profec B allows me to have TWO boost settings available - low (currently 9 psi for me) and high (currently 13 psi). Thus, I can run low boost for daily driving and with a flick of the switch hit HIGH boost (currently 13 psi) for stop light races.
Based on my hard test runs yesterday (Sat), both 9 psi and 13 psi are more than enough boost for daily driving and those occaisonal stop light races.
I mean - both my front rotors were SMOKING! There was a distinct burning smell in the air. I currently use mintex brake pads - will probably by some new rotots and pads - if the current ones are warped. Any suggestions?
AOA replaced both turbos (KO3s) and ICs with updated parts (my car is a 11/99 build date). No, they wouldn't replace them with KO4s. Believe me, I tried to get AOA to go 50/50 on KO4s. They would have none of it. I din't start chipping and making all the mods that I currently have until 75k mi..I'm currently @ 82k mi.
To answer your ? - I'm just cautious - the next set of turbos will be 100% on me. WIth a kid in college, the budget can't afford KO4s right now. I'm surprised that I was able to get the mods that I currently have - after paying these sky-rocketing college tuition bills.
I'll probably up the boost as time goes by.
The major differences btw the Profec B and the MBC (in parallel) set-up are as follows:
The Profec B is controlling my boost THORUGHOUT the power curve - I'm not deferring low end boost control to the N75.
The Profec B ALSO allows me to DIRECTLY control the wastegate - the N75 does NOT give you that ability.
The Profec B allows me to have TWO boost settings available - low (currently 9 psi for me) and high (currently 13 psi). Thus, I can run low boost for daily driving and with a flick of the switch hit HIGH boost (currently 13 psi) for stop light races.
Based on my hard test runs yesterday (Sat), both 9 psi and 13 psi are more than enough boost for daily driving and those occaisonal stop light races.
I mean - both my front rotors were SMOKING! There was a distinct burning smell in the air. I currently use mintex brake pads - will probably by some new rotots and pads - if the current ones are warped. Any suggestions?
10-17-2004, 02:23 PM
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Gents...I'm running HIGHER than STOCK boost on BOTH Settings....Correct Me If I Am Wrong.....But
stock boost is 7-8 psi (from my readings on this board). I'm currently running 9 psi on my LOWEST Profec B setting (low boost). My High boost is 13 psi..Yes..it could be higher..but I'm being cautious at the moment.