Hi guys,

I'm finally getting back to working on my car. I mentioned previously that I didn't like the low-end torque/acceleration loss I got from switching to the HSR. Will switching from the factory 3:23 gears to 3:73 restore some of my lost low-end power? Or would I be better off replacing the HSR with a FIRST setup? I know the HSR will pull higher but I miss the low-end/torque-fun of driving around town.

Thanks!

 

yes, put the gears in there.

 

I drove my HSR with 2.77's. It really wasn't that bad. I put 3.73's in, and they're great. I also end the 1/4 mile at the top of 3rd gear. Can't go wrong with 3.73's.

 

Thanks guys! I'll look into upgrading the gears.

 

I forgot to mention that I did 3.23 to 3.73's when I was an auto and it was a very very nice upgrade. took half a second off of my 1/4 mile time and gained 3mph.
Car accelerates much faster and easier with the numerically higher gears.

 

Hi guys,

My car is in the shop now getting the gears installed. Upon inspection, they discovered my car had a 9 inch Borg-Warner rear end. Is this rear end worse than the normal factory 10 bolt?

Thanks!

 

you mean 9bolt rear. It is actually stronger than the 10 bolt but the gears and other parts for it are much more expensive.

 

Did you ever tune this car? give it more timing in the 2400-3600 range and it will pick up some. Also give more timing in your cruise spots. Gears will really make it feel peppy tho.

 

Glad to hear its stronger... the guys at the repair shop were telling me it was weaker than the 10 bolt?

I haven't done any tuning myself. I had TPIS give it a custom tune (via mail) so I'm not sure how tweaked the timing is really. The car seems to pull strong in the mid/upper rpm range. I just lost my low-end response/power when switching to the HSR.

 

I've heard "the more bolts the stronger the rear end is".... I also have a 9 bolt borg warner rear, I got it cheap and swapped out my 10bolt when it pooped. It also has disc's and i hear they were in TA's originally.

 

im in the same boat, switched to hsr a few years back and miss the low end so this week i hope to get my car back from the shop this week with a new set of 3:73 for my 10bolt. i figured a b&m megashifter would work well with my gears and built 700r4.

 

Try setting base timing up from 6 to around 8-10 and see if it feels abit better

 

the 3:73s are installed now, been driving it around town. It feels great, perfect choice for the cars setup/ and my driving habits. Burnouts work awesome with gears, lol. next ill put a scaner on it, if everything is good i think id like to take your advice and bump the timing to 8 then if it feels good try 10deg. The shifter needs to be installed to as my car seems to shift premature for the past few months now... lots of little issues. is it possible i might need to play with the govener?

 

What size converter is everyone running here??

 

stock converter. what about yourself? what kind of block do you have/ whats the cam in your car like, lift and duration?

 

odd i didnt lose anything when i put in my HSR... but i had a custom tune done at the same time.... its all in the tune

 

im sitting at 40psi with the vacuum line conected. does this sound good for my setup? im not sure if i should increase pressure.

 

my full bolt on L98 with the HSR I ran 3.42 gears and 2800 stall. It seemed to like that alot. 1.71 60 foots at the track, which is faster than any of my stock TPI 60 foots with same gears/converter.

 

2000 TCI stall, 3.70 gears. Already know I should, and will, step up my converter. I'm just curious as to what size you guys are running and how it performs off the line. I know you're going to lose a little down low with the HSR but that power should easily be compromised with other mods. My cars still having some power issues and can't get off the line or turn the tires over. New valves springs going on tomorrow. My cam specs and everything about the car are in
What to expect from my 350 HSR, a few threads down from here.

 

well ive spent a few hours driving and playing with the timing/ fuel pressure. Wow very dramatic, ive recovered some nice hp just with bumping the timing and fuel pressure. its about 11deg timing with 44psi fp. Thanks for the advice about timing. It was as if someone turned on a switch.
The only thing im not happy with the gear swap is if i shake the car from side to side the wheels have a bit of play, i went back to the shop and said its normal i think he said its the c clips. sound farmiliar?

 

I did switch to the 3:73's and my low-end is better but nowhere near the torque of my old LTR TPI setup. With all the upgrades I've done, I would've thought I would easily be able to roast the tires. Sadly I can't

 

it seems like the hsr works better with built motors like yours, correct? im using a 406-11:1-Procomp 210cc aluminum-xfi292.. hopefully the hsr will be more fond of a bigger cube motor..

would a cam with a lower operating range help or would it kill hp/tq because its not matched to the HSR? im still a youngin learning dont be to harsh on me if thats a dumb question

 

my car was a tire melter before my tranny gave out.. i just dont understand why so many ppl seem to have problems..with low end and the stealth ram. I was running a 2500 stall from 7004r.com i had traction problems....

 

i think people are not spending money on a GREAT tune or trying to tune it w/o a dyno.. we have a bike dyno and its crazy how many ppl screw with there power commanders and just ruin a map.. OR ppl have weak motors and have trouble pulling thru the rpms

 

You must have another problem, I'm running a 355, 170cc heads, COMP XE-268, and an HSR on a pretty much stock tune with a 2400rpm converter and 3.42's and 1st gear isnt even an option for me, I have to ease it through 1st and let it get into second before I can start to get on it.

 

 

Hmm... I think I'll put my stock PROM back in and take it for a spin. Maybe it is in the tuning?
Thanks for the info!

 

Well I say a pretty much stock tune because when I went from my 305-355 I had PCMForLess burn me a "piggyback" chip for the 355 which all he probably did was change the injector constants to the 24's I put in. I'm waiting for spring to dyno tune the new set up so its been running on that tune, I bumped the FP up to around 46psi to be safe from going lean. Also I dont know what your running for initial timing but I can advance it to off the tab around 18*'s or so with no ping but it runs best at 14*'s initial and this on 89 octane. I'll have to get some videos, it idles pretty bad which is probably just in the tune but as soon as you get on it it wakes right up, its so responsive, I can only imagine what a real tune will do to it. You have more head than me, your cam is similar in duration but way more lift and you have a roller set up plus the XFI lobes are more agressive than the XE's, so I would deffinatly start looking elsewhere besides your gears, if you have a 2500 rpm stall converter and 3.73's you should be able to roast 1st with a stock LG4.

 

to irocz30589 and scamaro355.. what kind of hp/tq is your cars making? 1/4 ET? im hoping for 400+rwhp 450+tq and low 12s? but i cant find much info and yours are similar builds just a lil smaller

i have a 3.42 in mine sounds about perfect but all this talk about no traction in first is exciting me.. too bad i dont have a heated garage (10* in cincy)or id be throwing the 406 an drivetrain in, while i wait for the HSR for christmas..

 

I didnt get it dyno tuned or to the track this year, but depending on the tune I'm looking to put down somewhere around 300+whp and to run mid to high 12's. If your combo is 400whp healthy you should be into 11's easily with a good set up.

 

I didnt dyno tune just did data logging with a buddy that got into tuning his own stuff. As far as 1/4 ET and Mph the best i did with it was a 12.2 @ 119

i wish i still had the time slip so i could scan it and show you, because i figure some ppl on here wont believe that.

I just hope once you get that 406 in you start setting some money aside for a tranny and rear end... because it wont last I had over a grand in my tranny internals it lasted roughly 6 months behind the new engine. So im looking into a manual swap