chipped p75 xs ecu
brand new o2, stock timing, intake header exhaust, stock injectors t/b all that crap. you would think that with a chipped ecu it would run rich. the car hesitates and has very little power untill 4500 where it rips ***. this is a straight b20 motor. compression is 190 across. whats the deal?


[Modified by court, 2:51 PM 7/7/2002]

 

I/H/E can cause a motor to run on the lean side until you do something w/ your fuel set up. Who chipped the ecu? are you sure its the correct program for your set up?

 

ihe leans it out enough for it to bog at the low end? i know people that have no probs on a stock computer with intake header and exhuast, and a chipped computer is supposed to DUMP fuel in

 

try a stock computer to eliminate or isolate that as your problem.

 

I have read that in the area of 3500~4500 rpm with ls and b20s its called no man's land. Meaning unless you have a standalone to solve the dip in power (usually running lean) you are stuck with what you have. If you are running the LS manifold that could be the problem. Check out crower's dyno graphs for their cams, you can see the same dip in power in that area. This is supposed to be a common thing.

 

i dont see how the ls manifold is the prob. some b20's came with thats style mani. what manifold would you suggest to solve this porblem

 

if i remember correctly longer runners help in hight rpm but shorter runners help in the lower rpm.

 

the no mans land you are referring to is due to the intake style of the LS and B20 manifold. It's easier to get power in that region with a skunk2 manifold.

 

U are running an ls ecu which is designed for a 1.8 on a 2.0 engine...it will run lean... i have the same problem with my car.... Upgrade your fuel system and you'll notice the difference.... fuel pump, injectors and a fuel computer(s-afc) and you'll run perfect... or if you have the money get a standalone....

 

would gsr injectors be good for the b20? and would they also flow enough later running 9 lbs w/turbo?

 

Nope....dont go with gsr injectors...not worth it...run stock turbo talon injectors if you are strapped for cash....if you can afford name brand...get rc440 injectors...

 

why are they not worth it? just not worth it becuase how much you pay for almost nil gains??

 

'cos they are the same size as your stock injectors

 

I hate to rag, but:

A B20(B?) with IHE is not stock, especially if you are using the B18B intake manifold. Besides that, you are attempting to run a 2.0L engine with a 1.8L ECU. Can you see the problem yet? Unless that magic chip in your P75 just happens to be tuned for a low compression version of the B20Z, you are So Outta Luck.

If you look closely at the stock B20x and B18B torque curves, then imagine that fuel and ignition requirements follow those curves (and they do), you can clearly see why your engine runs lean before 4000 RPM and rich after 4500 RPM.

You can still use a "chip" in your ECU for better performance, but it will need to be based on a B20x program for success. You can e-mail me for more info if you want.

 

its the other way around,longer runners are for low rpm torque,shorter runners are for high rpms

 

yup...i couldnt have put it better

 

i thought the skunk2 mani was designed for higher rpm hp. and is there a good chip or program out there for the b20?

 

i use a DX (SOHC NON VTEC 1.6L) ECU

and it works just fine...from idle to redline

STOCK B20 with an intake.