By Trevor (130.155.6.50) on Wednesday, December 12, 2001 - 10:50 pm:

First of all i would like to thank everyone who makes this board possible. I know i wouldn't have been able to complete the City II turbo conversion in my 76 civic without reading through the previous messages on the subject and learning as much as i did. So a big thanks to you all.
Anyway, i finally got my civic up and running the other day and have had an absolute ball driving it around, i never thought it would be this much fun. I see what u all mean now about getting addicted to the little cars. Everything is running real well but it seems to be overboosting. I believe that the factory boost should be 12psi but it spins way past that and starts jolting very harshly at about 17-19psi (im guessing its running out of fuel). Ive thought about getting an after market boost controller but it would be good to avoid spending some money for a while. If anyone has had a similar problem or knows what this could be i could really use some help

Thanks
Trevor

By BOOSTBOY (130.194.13.164) on Thursday, December 13, 2001 - 03:47 am:

Hi Trevor,

The boost cut on my city is at about 15-16psi. You can override this very simply if need be. Are you using any form of pneumatic boost control at all or is the line from your wastegate actuator to the turbo compressor housing standard? For the turbo to overboost the wastegate isnt opening, or is opening late. Check the above mentioned line for leaks, this will cause overboosting. If all is standard without leaks, boost should hold at 12-13psi, depending on exhaust and intake modifications.

Email me if you need more info etc...

boostboy@hotmail.com

Have fun boosting around!

By BOOSTBOY (130.194.13.164) on Thursday, December 13, 2001 - 04:29 am:

The jolting is definately the boost cut. It's pretty scary huh!?

By Charles (152.91.9.49) on Thursday, December 13, 2001 - 03:28 pm:

If you have a very open intake and exhaust and the engine is in good condition it will hit boost cut everytime usually at about 5500rpm (which drops 1000rpm off the redline) especially on a turbo 2 motor. One way around it is to tighten the wastegate actuating rod, but if the car is supplying enough fuel (check on a dyno then leave it and fit a boost cut lifter onto the map sensor b (not a). They cost about $50 and will give you an adjustable cut.

Charles

By Trevor (130.155.6.20) on Saturday, December 15, 2001 - 08:05 pm:

Right on the money. I checked the line from the wastgate actuator to the turbo housing, and sure enough it had a massive crack in it. So i replaced that and boost now holds at 12-13psi. Its not quite the animal as it was before, not as much kick from the turbo but now i can actually rev it out which is good. So i think now its time to slowly increase the boost, install the intercooler and see how it goes from there. Thanks Guys.

Trevor.