eriksseven

iTrader: (6)

The car is an 88 TII that, until recently had only very basic bolt-on's.
-rebuilt motor
-higher compression 9:4:1 N/A rotors
-'extended' RB street-ports
-ported WG
-full 80mm exhaust
-K&N drop-in filter
-MBC running 11psi max boost
-Greddy Type-S BOV

So I've been 'modding' my car lately and have had some problems with slow spool up, uncontrollably low 'max boost' via an MBC (10psi max) and QUICKLY dropping boost, down to 6psi by redline.

My 'fresh mods' are:
-T04B hybrid turbo with a heavily ported WG with a larger door welded on
-Walbro 255lph fuel pump
-Greddy 720cc secondary injectors
-Apexi S-AFC

The previous owner had seen 247whp on the dyno at 11psi and I was definitely nowhere close. Before the fuel mods and hybrid, my stock turbo was probably faster than what I was seeing...

To fix my strange boost problems I decided to put more tension on my WG by 'shortening' the actuator arm and purchasing and installing an EBC.

Duuuude... SUCCESS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!

I started "the day" by calling some local import shops and asking what they had in stock for EBC's...

A place called Racing Concept was selling Greddy Profec-B spec II's for $340...

Another place called European Technologies (or something) had ONE, old style Greddy Profec-B's in stock... When I was talking to him on the phone he mumbled something about "hooking me up" when I asked him how much he wanted for it. He said "to himself", "well it's $320 retail... Let me bust out the calculator"... Several moments later he's like, "well, I could probably hook you up for $300 even".

I was like, "uhhh, I'll call you back".

On ebay, if you can even FIND the old-school Profec-B's, they go for about $200 or so. The newer Spec II's can be had for around $270+shipping. This guy wanted $300 for the old model... And I was actually considering, lol.

To make a long story short, a 'VW Corrado' friend of mine called the European import place and talked him down to $255+tax for me. Except he told the guy "I was on my way"... lol.

Pretty much I was obligated to drive up there to at least check it out. Turns out it was BLUE, and not just blue, but CLEAR BLUE?!?!?!?! I asked if I could open the box to look at it and he said no... I asked if he had a catalogue with pics... He didn't because it was the old kind, lol. So I went online at the Euro place and found a pic... WTF!?!?!?!? It looked like a frikkin' SPACESHIP when lit up! Not only that, but when I was in 7th grade, I had some heinous PAGER that was the same color casing, lol! Like an aqua bluish green.

I bought it...


LOL, I paid $275 for the ugliest EBC imaginable.

On to the success story:

It took me nearly 2 hours to remove the turbo (don't ask), but when I did, I got a good chance to take a look at the twin-scroll setup to see how the actuator arm works. I tested it's ability to close by pulling the door into the 'closed' position (the actuator naturally "sucks" it into the 'open' position). I then put my thumb over it's vaccumn line and let go of the door and it held the closed position just fine. When I took my thumb off of the vaccumn line, it snapped back into the open postition. So that works... Problem is, I had, had it hooked up to a line that produced NO VACCUMN!!! (wow, I know)

Upon inspection of the turbo, the large WG flapper door was intact and everything looked good. I tested the WG actuator arm and it felt normal. I then did my first "mod" and drilled a new hole on the arm and 'stretched' the arm to use this new hole.

General consensus is it's good to do this on a hybrid turbo setup because it puts more tension on the WG. Therefore the wastegate opens later (allowing quicker spool for the hybrids and in my case, the ability to hopefully run more boost).

While everything was apart I took the opportunity to replace some of the vaccumn lines and clean up everything around the turbo. I still have my emissions crap, so making sure everything was going to be connected correctly properly and securely was important.

Next, I installed the 'engine bay' part of the Profec-B which was pretty easy because they supply you with everything you need.

I put everything back together and made sure I wasn't running everything off of the same vac. source. I had originally tapped the boost gauge and BOV into the UIM line that goes accross to the boost sensor. I decided that since I was going to need vaccumn sources for the twin-scroll actuator and now the EBC, I should use some other 'nipples'.

I pretty much got everything situated and re-installed. I got the EBC control unit installed easily and started the car... Everything was fine. I let it warm up and took it out to drive. After some warm-up driving I boosted for the first time (with the EBC all the way down). In 1st gear it hit 6psi by 4k RPM's!!! In second it was around 9psi by 4.5k RPM's!!! After doing some more warm-up I took it to redline and it held a solid 9psi all the way through!!!

I had already set my S-AFC for safety, pretty much +5% correction climbing to +10% from 4k RPM's to 8k RPM's.

Then I turned up the boost...!

Pretty much after about 30 minutes of tuning, my new numbers are thus:

Hitting 9-10psi in 1st gear

In second gear I'm at 9psi by 4k RPM's, 13psi by 5.5k RPM's, falling down to 10psi by 7.5k RPM's

In third gear I'm at 10psi by 4k RPM's, 13psi by 5k RPM's, falling down to 10psi by 7.5k RPM's

Fourth gear is similar.

All of this is with a rough tune on the S-AFC.

The car's fast now, lol.

Thanks for the help everyone.

BTW, By next week I want to have a FMIC, TID and my car dyno tuned for 15psi..

I'm shooting for 300hp+ to the wheels. Anyone have any predictions?

eriksseven

iTrader: (6)

I'm going to sleep now, lol.

BTW, while I was tuning the EBC I got pulled over! My friend in his VR6 Jetta was behind me at a stop-sign and I was unaware that behind HIM was a cop! Well, I TOOK off from the stop-sign (to continue tuning) and I shot a HUGE flame when I shifted into 2nd gear. I was like, "wow, Corey's hitting it too, he must've been stoked on that monster flame". Well, a split second later I saw some pretty blue and red flashing lights... lol. It wasn't Corey, the cop had veered around him when he saw/heard me take off!

Pretty much I just pulled over, cop shined his 'light' on me and a moment later he got out of the car and came up to my window.

"going a little fast there..."

I said; "uhhhh"...

He said; "what was that"?

"Yeaahhh, ummm, well, my car's been running weird and I'm just trying to fix it..."

"License, registration and insurance" were the next words out of his mouth, lol.

He looked at my I.D and said that he saw us take off at a 5 corner stop-sign earlier up the road and that he knew we had been speeding excessively.

He told me to slow down and gave me back my license.

I resumed tuning soon after (in a different city, lol)

sleeperfc

nice man... now with a 3" tid the boost wont fall off...

with your setup you should make 300... good luck and gj man. im glad you kept at it till you figured it out.

time to punish the streets!

CyborgRyu

iTrader: (8)

I don't quite understand. Did you just change the vaccuum line or did you make your flapper bigger? I want to fix my problem too! maybe I should make it a 3" TID then give it a try.

Wankel7

Take it to teh track already! Good job man.

James

RX_AV8TR

I think that's the best feeling in the world, to have a damn gremlin under the hood you just can't find and after all unimaginable frustration...bingo.....priceless.
I've been using the same Greddy Profec A since '97 and no problems...Greddy is good stuff.

Whenver your clutch gives out seriously consider a lightweight flywheel, on your first run you'll say...holy ****!!....guaranteed.

RotaryEvolution

iTrader: (30)

disconnect the twin scroll line temporarily and take it out and see what it does.


the twin scroll is run off a solenoid actuated vacuum source so it sees vacuum to 2700RPMs then it pulls the vacuum off so the flapper will open. could be the cause of the drop in boost. you really shouldn't be dropping boost at all.

eriksseven

iTrader: (6)

^ yeah... I didn't get a chance to really test out the *possibly* working twin-scroll last night due to the lack of light.

It is puzzling that I can't seem to get the FULL boost capabilities out of this setup.

eriksseven

iTrader: (6)

Well, as strange as this may be for some people, I didn't fully grasp the concept of vaccumn and vaccumn lines... So when I was putting together my rebuild I just did my best to attach all of the lines to where it LOOKED like they were supposed to go. I didn't understand how to check vac. or what lines necessarily did what.

I pulled off the soft hose I had attached to the twin-scroll actuator's hard-line and found that upon placing my finger over the 'source' hard-line, there was no 'suction'... After pulling the turbo and getting a chance to fully understand the workings of the twin-scroll, I saw how it was opened and closed and determined that it needed that 'suction' to hold it closed and as soon as that suction turned to positive pressure (or less suction) it would allow the twin-scroll door to open... Pretty much I didn't touch the 'door' of the twin-scroll, just found the right vaccumn source for it to correctly work.

RotaryEvolution

iTrader: (30)

i still say you shoulda ripped that ****** off... i did away with my twin scroll, it doesn't quite have the umph it did off the bottom but it screams once the boost kicks in, i can't wait to install the microtech, 4 720's, front mount and crank up the boost on my hybrid!

sleeperfc

cant get full boost? you got 13psi right? what do you mean?

RotaryEvolution

iTrader: (30)

i would expect that it should be able to produce more than that, it's widely known that with large ported wastegates on a hybrid turbo that the pressure likes to force past the wastegate flapper door. any pressure drop to me would be unacceptable.

RX_AV8TR

Erik you don't have to do any of that to check the twin-scroll, remove the cap on the throttle cable spring assembly and accelerarate the car to about 3000K RPM (looking for 2700) and you should see the actuator shaft move...

sleeperfc

well when it was on my car...

the stock TID choaked it down a god bit. i put a 3" tid and the boost would not fall off at all. full 13psi to 7.5k when i shifted.

turbo-polak

how much was the hybrid? whered ya get it from?

thanks,Dan

sleeperfc

i paid 450 for it at a local shop called turbo exchange. he said he can take a hybrid like this one and upgrae it to a 60-1 with a .60 front cover for just a few hundred.
i wanted to do that with this turbo but i got a t70 so plans changed.
im pretty sure they can do mail orders....
704 721 6661

this guy knows his sheet.