help s13 starting prolem
 

I have 91 s13 with a blacktop. I didnt do the swap. When the car is cold i have to crank the hell out of it to get it started! What can this be? When it starts it runs great.
thanks

To be honest, i'm not an expert, but could it be somet to do with fuel supply??? Is your fuel pump OK, pressure regulator set correctly to supply this new engine???

check the main 3 air fuel spark anything to do with those is ur problem u cant have one with out the other

its a new fuel pump and the stock regulator. Why only when its cold? One thing once in a while if i rev the car the rpms drop very low and almost to a stall. If i tap the gas the rpms drop before going up.

Again, i'm no expert, but it sounds like a fuel supply problem to me. When the car is cold, it will be running automatic choke/running rich whilst the engine gets warm. Just sounds like the fuel pressure needs to be increased to supply the new modifications. The stock fuel pressure may not be adequate for running your engine with a turbo??? What kind of a fuel pump have you??? you may need an uprated pump. I had to upgrade my fuel pump when i increased turbo boost on my car although i didn't have the problems your having. Maybe take it to a nissan garage and ask a qualified technician for his advice??

change ur fuel filter, check your maf, do a tune up ( cap, rotor, wires, plugs )

Its realy acting up. When im in first gear if i go in to boost it starts to bog out and back fire. Could this be a boost leak?

check your spark plugs for a starter.
I'm having this problem at the moment. I've done some research on the british sx owners club and found 3 possible problems with regards to this.
1) spark plugs are worn out or have insufficient/too large gap.
2) coil pack breaking down so try some coils you know are working from a local club240 member who would be willing to lend them to you.
3) a boost leak.

I took my spark plugs out and they were ready for replacement, so hopefully when my sparkplugs arrive, this will sort my problem. hope you sort this soon.