So, I have an S5 Bridge-port that was originally carb'd when I got it. I took the liberty of swapping the carb setup with S5 TII port-matched intake manifolds, 465cc primaries and 720cc secondaries. I'm still trying to get the timing adjusted for more efficiency, but no matter where I position the timing, I get a sputtering/hesitation from 7k to 8k rpms. When it was carb'd, it went up to 9k rpms. Don't get me wrong, there's a huge acceleration/throttle response difference, but it's really annoying to have lost about 2k rpm "redline." I am running a stock N/A S5 computer and that might be the problem, but I figured there might be something else I can try to gain a higher rpm reading. Anyone with ideas, let me know.
Thanks

 

if i was you i will go back to the carb setup,with a nice holley,demon,webber carb it will run way better that with the stock sistem,s5 computer,flow meter,map sensor and ecu are holding you back,you can try advancing the timing to the point that the cas wont move anymore,higher fuel pressure and adjust the flow meter a little,i seen a couple of BP on stock ECUS and this changes help a little,your best choice will be getting a standalone of some sort in order to run the engine the right way.

 

I understand how to adjust the timing,......
...but how do you adjust that?

 

you are gonna need some kind of aftermarket fuel pressure regulator and the flow meter has a a adjusting screw that is covered with a small black cap,remove the cap and play with the screw and see if that helps,the only bad thing about playing with the meter is that it will affect the complete fuel timing map so you need to find the sweet spot.

 

Do you know which way to turn the screw to allow more air? B/c I think the sputtering has to be from running rich with the 720cc secondaries at high rpm.

 

that should be part of the problem(injectors 2 big)take off the 720cc and swap 2 550 before you do anything else and see what happens.

 

Well I'm hoping to just be able to make adjustments to accomadate the injectors as is. I did notice a hp increase when putting on 720cc after trying out my buddies 550cc's. I just need to find out what to do in order to compensate for the increase in fuel. That's why I'm considering adjusting the airflow meter. I want my BP at full potential as an N/A before I turbocharge it.

 

Your going to have timing issues with S5 computer. I don't know if anyone has really successfully run a bridge on a S5 without a piggyback or just going standalone.

 

The S5 intake manifold and ecu are holding you back. This is precisely why bridgeporting a 6 port motor is a bad idea.

 

ok......well I'm asking about ideas on helping my situation, not how what I have is a bad idea. I bought the car as a carb'd BP. So the BP was already done and I'm not a fan of carbs so I swapped to a TII S5 manifold that I ported and polished. So for stock manifolds, its the best I can get. Now, do I need to get an MSD ignition....or megasquirt....or standalone...or what...?

 

Well I'd suggest either going back to the carb, which you've said you don't like, or at the very least get ahold of a standalone ecu. Your Holley manifold with a Holley style throttlebody would work nicely.

 

I know it would be more wiring, but maybe try a s4 ecu before spending lots more money on stand-alone or piggybacks

i believe bad83 did good with a s4 ecu

 

The s5 ecu is too "smart" to deal with a brigeport. good luck getting it to work i don't think you really have any options to make it work other than geting rid of the s5 ecu, sorry. Go stand alone, carb, or S4 ecu.

 

MAn that sucks.

DUde. I have some 550cc's for s5 if your interested in trying them out. ANd throw the wideband on to see how its going.

 

did you ever make a desision on the ecu issue?

 

Hhs