went to track and have some problems tranny/rear end/ ? please help

[calvo]

Ok went to the track for the first time this year since I went to 4.10 gears from 3.73. I have two problems.

1)The tranny does not want to shift into 3rd with nitrous running. I have to turn it off let it shift into 3rd than turn it back on. Why? any ideas? Its the first time its done that, it did not do it when I had the 3.73. I spray from the launch thorugh all gears and this jus started after I put the 4.10 and LSD in.

2) car is toping out at 89 MPH (ouch) even with Nitrous. Im hiting 89 MPH about 3/4 down track at 3,400 RPM's bottum of 3rd gear. This one really has me pissed. I use the granatelli Granspeedo to corect the speedometer dont know if it has anything to do with it.

My car is set up with the folling
FTRA w/ K&N shaved airbox with silancer removed
Headers, 2.5" cat cutout and flowmaster exhaust
B&M shift kit, 4.10 W/LSd (stock = 3.08w/o LSD)
and a 75 shot nitrous

Thanks for your time and help in advance

[Die Ford V8]

sorry man, dont have a clue??

[WickEdSix9838]

its hitting the speed limiter at 89 mph and i have no idea why it wont shift into 3rd.....im sure all the granatelli did was fix the speedometer and not fix the speed limiter just like the SLP recalibrator does....

[calvo]

So if I get rid ofthe speedlimiter I should be ok?
Also our cars are soposed to be limited at 118 right? befor I installed lower gears the car would go faster then that and was able to top out the speedometer, is there any reason for that? Would it have any thing to do with my problems now?

[RallyRed 98]

i have to suspect that the 4.10s are making your PCM think your car is topped out so it's stopping you right there.

will the car shift into third with nitrous, just not at WOT? that would be an interesting test. i feel like all of this is connected to your 4.10s confusing the PCM.

probably time for tuning/custom pcm.

[calvo]

I think the 4.10 are conected as well. Just not sure how. I want to find out what the computer is thinking before I do anything, so I can fix it right. Also wanted to do a cam and was hoping to wait till after to do pcm.

Not so sure its a good idea to try thre 3rd shift with notrous woth out WOT? maybe tomarrow I might try it jus to see what happens(hopefully nothing bad) I will let you know and keep everyone updated.

[Razzer]

The 4.10 Gears are making you driveshaft turn faster than when you had 3.73's, to solve this problem you need to get the Hypertech 3 and reprogram your car for 4.10 Gears and remove the rev limiter, and possibly the speed limiter to. I believe that this will solve your problem. Right now you car thinks your going much faster, and that you are redlining the engine. The difference in gear ratios is 4.11/3.73 = 10% more rpms

[RancidCamaro]

Originally posted by Razzer:
The 4.10 Gears are making you driveshaft turn faster than when you had 3.73's, to solve this problem you need to get the Hypertech 3 and reprogram your car for 4.10 Gears and remove the rev limiter, and possibly the speed limiter to. I believe that this will solve your problem. Right now you car thinks your going much faster, and that you are redlining the engine. The difference in gear ratios is 4.11/3.73 = 10% more rpms

He has a 1999, the Hypertech Power Programmer 3 will not work on his vehicle.

You are correct, though, he does need a new solution. Possibly a JET SCU, or if that just did what your granatelli module did, Wester's Custom Programming may be another option for you.

[Razzer]

Wow, I just saw your stock ratio was 3.08 that is a hella difference compared to 4.11. You will need to do all three mods to make you car go faster than 89mph. 3.08 to 4.11 is 33% more rpms. That works out to be right, your car is topping out at around 3400 rpms, Did you also change your tire size? You need the mods previsiously listed for your new mods to work correctly.

[calvo]

Yes I did change tire size from 235/55R16 (I think)to 275/45R17 in rear and 255/40/R17 in front. I tried the jet scu 2000 with the 3.73 did not work well (it cant make that big of a change)and craped out on me down the high way. not much comfidence in it.
as RancidCamaro said there is no HPP3 for my car [img]graemlins/bs.gif[/img]

also was hoping to do a tranny rebuild and, cam and port the heads befor I get the pcm reprogramed but dont have money to do all that at once.

I still have a new in box Jet SCU 2000 from warernty but not sure how it removes speed limiter can someone help me? may be I can try it again to get me by till I get the rest of my mods done and get the pcm programed.

instructions say:
simply move the top speed limiter jumper from the "-" to the "+" postioin. the jumper can be accessed through the face of the SCU2000. the SCU comes with the speed limiter set to "off" position from factory.

OK my questions
1)what and where is the speed limiter jumper?
2) can I jus hook up power, ground, and the jumper since I alretady have the speedo corrected? or should I should i set it to make no change and run both the jet and granatelli?

[calvo]

Never mind about the SCU 2000 I called today and got it worked out. I will probally give it a try again and see if it helps.

Any other ideas, suggestions or comments?