I looking to add a lower pulley and asked a few questions of one of the tuners out there which created more questions that I thought would be best answered by the boards...

I'm running a chip and supplied the program number to the tuner... the question was:

1 - Between the 4# and the 6#, I think i want to go conservative but with the chip I have what do ya recommend... Answer - Best choice is the 4" it is rated at 5400 rpm if you change the program on the chip to 5900 rpm shift it will be a 6" pulley. This is still under the max rpm limit of the compressor.

2 - Am I correct in thinking that the chip reburn for the 6# will up the rpm shift point to 5,800 and the chip I have now is 5,400?

Do we really want to go that high with all the bottom ends falling apart?
Answer - We set the fuel shut off at 6100 with the shift at 5800 with the 4". The 2002 ford Harley truck has a 6000 rpm shift point. We use that as a gauge for the limits on the lightning.

More ?'s - According to the SVT literature... redline is 5,250 and fuel shut-off is at 5,400... are you guys running 5,800 RPM shift points are am I missing something here... what are y'all shifting at and how high are you running it with the stock internals???

Hopefully y'all can give input to this...

 

I think some of your facts are wrong. You may want to call your tuner again and make sure your info is correct. Most tuners are not changing the factory rev limiter. I believe they are only bumping the shift points up 200rpms from factory. What is changed with the larger pulleys is timing and sometimes fuel duration. You need to find out what your A/Fs and timing at WOT are. I do this by using a program called "Autotap".

 

Actually... those answers are the tuners facts and they didn't wash with me at all hence the post.

I really am looking at either a 4# or 6# in the hot texas climate... I don't race it so the program needs to be a little on the rich side for the occassional blast down the Interstate @ 100+ (a little more than the ole 1/4 mile routine)... I have a Diablo but maybe the Delta is the way to go if I need two programs.

The Autotap looks pretty cool.. should do the job and allow you to better tune the chip(?). Right?

 

I have the Autotap. Mine shows the o2 Sensors and the voltage, how are you converting it to a/f numbers ??

rickgig
Check out the Talon forum some of the local guys can offer real time feedback on mods...

Doug

 

If you don't race at all I would go with a 4# pulley at the most, really if it were me I would go with a 3#. Just driving around town all day with a 6 is just going to add long term wear and tear with the added heat your generating. The by-pass valve is not even big enough to handle all the extra air being pumped when in a vac state with a 2# much less a 6#. You also need to make sure your tuner knows you want to run at top end speeds. Most of us are tuned for 1/8 and 1/4. Deep in the throttle and detonation sets in and it will not take much of that and the story is over.

 

Thanks for the info...

This is the type of stuff I am looking for...

Great help...

 

Your welcome

 

Optimum shift points will be determined by a lot of things. Transmission ratio spacing and rear gearing are important, as well as the Hp and torque curves.

I am running a conservative tuneup, with 2# pulley. The gearing on my truck is stock at 3.55.

When we dyno'ed the truck after going to the 2# pulley, we found the truck gained very little Hp at the top end, compared to the Hp and torque gains in the midrange. We decided to reduce the shift point back to 5200, from 5600 where it was with no pulley. The reason was that the truck stopped making Hp at 4800 RPM. I decided that it would be better to shift early and get back into the meaty midrange.

I definitely made the truck more responsive on the street. It is still pretty quick on the track, despite the very limited mods, and the 3.55 gear.

I also wanted it to be reliable, as it is a daily driver.

 

Which tuner told you this? I KNOW it wasn't Sal, JDM, or JL.

Excuse me, but there is NO WAY the HD turns to 6k. It has the same shift points as the Lightning.

 

You're right... it wasn't Sal, JDM or JL... but I do live in Texas if that helps.

I really don't want to mention the tuners name and have the guy get fried...

From the replies to this thread... most of us owners can see something is up when the advice is out of the norm.