B9B Swap...acting funny....

[SHOman24v]

Yesterday i swapped in the B9B computer...but for some reason it starts to go crazy, the car shakes alot and the idle jumps around and sputters, it does it sometimes tho and then it goes away. is there some type of crankshaft relearn process that i need to do? Does the B9B really revv to 7800, I still see it revving to 7300....Or im wonding if its because i didnt block off my egr and unplug the sensor that goes to it, any responces would be great.

<small>[ February 18, 2004, 10:21 AM: Message edited by: SHOman24v ]</small>

 

[Yamaha V6]

B9B has no EGR capabilities that I know of, and may be treating it as a vacuum leak.

 

[NotSoSlowSHO]

Didnt CA 1989 SHO's have EGR?

 

[twr]

NotSoSlowSHO:
Didnt CA 1989 SHO's have EGR?

Yes - but they used a B9C computer.

 

[NotSoSlowSHO]

Ah, thanks

 

[SHOman24v]

nevermind i fixed it, i just needed to block off the EGR

 

[AutoSHO]

SHOman24v:
Does the B9B really revv to 7800

No.

All stock SHOs have a rev limiter at 7300 RPMs.

 

[twr]

AutoSHO:

SHOman24v:
Does the B9B really revv to 7800

No.

All stock SHOs have a rev limiter at 7300 RPMs.

Not always true, my 89' ran all the way to 8000 RPMs and I have heard of a few others that did too.

 

[Yamaha V6]

I heard the rumor that the EARLY 89 (aka calendar '88) B9B's went through with no / higher redlines, but I thought people determined the tachs were off, or was that another rumor?

 

[92lemon]

Thats funny, my 92mtx revs all the way up to 8000 ??!!!! I know that cuz I pulled on a brand new accord v6 in 3rd all the way to 95 =P

 

[Hack]

shrug My 89 has a W0Z out of a 90 or 91 and I have seen approximately 7500 rpm indicated and not hit a rev limiter. Could be that my tach is inaccurate though.

 

[AutoSHO]

92lemon:
Thats funny, my 92mtx revs all the way up to 8000 ??!!!! I know that cuz I pulled on a brand new accord v6 in 3rd all the way to 95 =P

3rd gear at 7300 RPMs is over 100 mph. Your tach is wrong.

 

[Axianator]

Just a little correction, boyz and girlz.

All of the V6 MTX calibrations (B9B, B9C, B9B1, B9C1, LOS, WOZ, X2J, W2Z) are rev limited to 7297.13952 rpms from the factory.

All of the V6 ATX calibrations (H3Z, H3Z1, H3Z2 and D4U1) are rev limited to 7000 rpms for all four forward gears and 4000 rpms for neutral (the H3Zx cuts out at 4k and comes back at 3875, the D4U1 is set at 4k steady).

Probably more than you wanted to know, I'm sure. wink

 

[Doug Waschenko]

Sorry this reply is a little late but just saw it on a search.
My '92 doesn't appear to have a rev limiter. I do 110mph in third gear getting on the interstate, not regularly but on occasion. I think that's around 8,000.
It's an X2J.

 

[yamahaSHO]

Doug Waschenko:
Sorry this reply is a little late but just saw it on a search.
My '92 doesn't appear to have a rev limiter. I do 110mph in third gear getting on the interstate, not regularly but on occasion. I think that's around 8,000.
It's an X2J.

Gauges are most likely inaccurate... OR, check to see if you have a chip.

 

[Axianator]

yamahaSHO:

Doug Waschenko:
Sorry this reply is a little late but just saw it on a search.
My '92 doesn't appear to have a rev limiter. I do 110mph in third gear getting on the interstate, not regularly but on occasion. I think that's around 8,000.
It's an X2J.

Gauges are most likely inaccurate... OR, check to see if you have a chip.

Using a lightened flywheel, such as a Fidanza, or different-sized tires from stock can either raise your rev limited (flywheel) or throw your speedo off (tires).

 

[AutoSHO]

Axianator:
Using a lightened flywheel, such as a Fidanza, or different-sized tires from stock can either raise your rev limited (flywheel) or throw your speedo off (tires).

No, on both counts. The flywheel absolutely, positively, 100% has nothing to do with the rev limiter programmed into the engine computer.

Smaller tires will make the speedo faster than the car is actually going, but it does not change the speed indicated at a given RPM. At 7300 RPM in third you are doing 106 mph.

I very sincerely doubt there is any SHO out there without a rev limiter that is completely stock. A chipped car can have no rev limit (bad, bad idea) but other than that, your car will be limited to 7300 rpms.

<small>[ March 15, 2004, 08:43 PM: Message edited by: AutoSHO ]</small>

 

[revhardSHO]

AutoSHO:

Axianator:
Using a lightened flywheel, such as a Fidanza, or different-sized tires from stock can either raise your rev limited (flywheel) or throw your speedo off (tires).

No, on both counts. The flywheel absolutely, positively, 100% has nothing to do with the rev limiter programmed into the engine computer.

Smaller tires will make the speedo faster than the car is actually going, but it does not change the speed indicated at a given RPM. At 7300 RPM in third you are doing 106 mph.

I very sincerely doubt there is any SHO out there without a rev limiter that is completely stock. A chipped car can have no rev limit (bad, bad idea) but other than that, your car will be limited to 7300 rpms.

I agree with you 100%. We all have computers in our SHOs therefore we all have rev-limiters in our SHOs. Ford did not just leave that programming out. The 89 tach especially, tends to read a bit optimistic at higher rpms. I see about 7700rpm before the rev-limiter kicks in.

Chris if you have larger sidewall tires it will effectivly make a higher gear ratio - giving you faster top speeds in any gear. (save 5th).

 

[AutoSHO]

I agree, changing the rolling diameter of the tire changes your actual speed. It does not, however, affect indicated speed or the relationship between RPM and Indicated Speed in gears. That will not change unless you change gear ratios or speedometer gears.

 

[zsho]

how much power can be had at above 7k without many mods anyways?

my 280zxt starts to lean out pretty good at 7k