Is there any mods for 91 940 turbo? What kind of air filter can i get. any exterior mods.

 

Check the link in my sig for a starting point....

There is also a link on the top of every page here with a list of sites for volvos.

Edit://

This is also a PDF floating around the internet about a stage modification for the 700/900 cars.
I belive there is a post similar to it in the RWD FAQ's from Adub.

 

Free mod: remove restriction from the base of the air filter box(in the intake duct) and remove the plug from the hot air inlet duct. This will more than double the air the stock box can flow, and the stock box is very good when this is done, better than a cone filter. Teh restriction is now the AFM, don't touch the AFM.
Cheap mod: external boost control, wind up to 10psi. 10psi is max on stock engine management so do not exceed this.
Not so cheap mod:cat back 2.5 or 3" system. Use big mufflers. Good for 2psi boost without touching a thing. I'd do exhaust as your first $$ mod, it's that important and makes such a big difference.
Essential mod: Fred's (HiTuning) chips. Run up to 16psi on stock turbo. Save, skimp, find the money for these.
BUT! Before you do any of this, replace leads, plugs, rotor, distributor cap, fuel filter, air filter and ensure you have stock fuel pressure at the fuel rail. Make sure car is not throwing any codes too.
DO NOT run any excess boost until you are sure the car is in good condition, if it is, go crazy.

Regards, Andrew.

 

where is the restriction in air duct and hot air duct and What is best muffler don't want sound ricey What spark plugs

 

NGK BPR7ES plugs

Any freeflowing muffler will work. There is more than the exhaust which makes hondas sound like they do...

 

so any 2.5 muffler will work what about a flowmaster and wont affect turbo and i want to get a filter for it do i need to get a tube for wires to hook into or just plain tube

 

also i just read a thing called piston slap. my engine makes like a knocking noise when it starts up

 

these motors are loud. I wouldn't worry about it.

wait for the experts...