I have a s4 vert and i just picked up a 89 non turbo parts car with a s5 na ported motor by pineapple racing for 800 bucks plus a butt load of parts and a front gtu clip motor and all.

Now, i know s4 - s5 swap is all really worth it but my s4 st port na is getting new coolant seals so it is out of the car at the moment and i just found this great deal on a parts car with a s5 st port by pineapple racing with at over 120psi in each housing. so it only made sence to me to put it in and have 2 street ported motor's.

here my question will the s5 fuel rails work with a s4 intake manifold and fuel injectors?

Im swaping all the s4 stuff to the s5 motor.

 

Why keep the S5 fuel rail when you're swapping the manifolds to S4?

Just keep the fuel rail and manifolds the same series [since it's an S5 motor you should probably just look up how to use the S5 intake manifolds, they're much better: VDI is awesome] If I remember right, all you should have to do is slap the S4 OMP on, bend the control rod to clear and use an S4 throttle body.

 

+1

 

You can't attach an S5 secondary rail to an S4 UIM (or vice versa). But you can use an S5 primary rail. The S5 primary rail is just shorter to allow clearance under the S5 UIM, which means even more clearance under the S4 version.

Use the S5 manifolds on the block. It's worth the extra bit of power you get. Similar: http://homepage.mac.com/carldavis/intake.html

 

^ Ok im wanting to keep the s5 intake manifold and i need to keep the emissions on to pass smog out here.
can you send that link to my email address? For some reason it doesnt fully open up for me.

 

which s5 fuel rail to replace the pulsation damper on an s4?

 

The PD is always on the primary rail for US cars. The S5 integrated PD can fail too, it's just slightly better. Of course when they fail, you get to replace the whole rail.