PAGING Bob Cosby---->
Thread Starter
Joined: Nov 2001
Posts: 7,303
Likes: 4
From: Delray Beach, Fl.
PAGING Bob Cosby----> Bob I wanna thank u for helping me.I gotta tell u that alot of my FORD buddies are VERY IMPRESSED with your Cobra.They constantly talk about your car and the ET's it runs given its mods.Okay enough of the brown nosing.I need your help with my car.Here is the info u needed....
My PEAK TQ is 401RWTQ at 4600RPM and carries it to about 5000.My PEAK HP is 441.5RWHP at 6500 and starts to drop off at 6800.
I'm so glad u talked about the GEAR/ET/TIRE combo.
Cold u elaborate on my decision to run a 4.56/28 combo?I was told the larger tire along with the 4.56 gear would get a HEAVIER car moving quicker outta the hole and get me a slightly better 60ft and 1/8.Then it would continue to help on the big end.I'm not one of these MPH guys that OOHH and AHH over top speeds.I want MAX ET Bob.
A friend told me the larger tire with its larger rollout is a BIG HELP over the 4.10/26 combo?Any help Bob wold be great.
JS
<small>[ April 10, 2002, 10:35 AM: Message edited by: JS ]</small>
My PEAK TQ is 401RWTQ at 4600RPM and carries it to about 5000.My PEAK HP is 441.5RWHP at 6500 and starts to drop off at 6800.
I'm so glad u talked about the GEAR/ET/TIRE combo.
Cold u elaborate on my decision to run a 4.56/28 combo?I was told the larger tire along with the 4.56 gear would get a HEAVIER car moving quicker outta the hole and get me a slightly better 60ft and 1/8.Then it would continue to help on the big end.I'm not one of these MPH guys that OOHH and AHH over top speeds.I want MAX ET Bob.
A friend told me the larger tire with its larger rollout is a BIG HELP over the 4.10/26 combo?Any help Bob wold be great.
JS
<small>[ April 10, 2002, 10:35 AM: Message edited by: JS ]</small>
TECH Resident
Joined: Nov 2001
Posts: 908
Likes: 0
From: Knoxville, TN
Re: PAGING Bob Cosby----> Hi JS,
I must first say that I wouldn't give my thoughts any more weight than any racers ideas concering tires/gears. They are simply my ideas based on my experiences, knowledge, and some assumptions. Please don't dismiss others out-of-hand. That said...
If your peak power is at 6500 rpm, then I'll likely want to go through the traps as high as humanly possible with that stock block. If that is 7000 rpm - cool, the higher the better. In simple terms (which is all I can really relate to anyways), that means as much gear as the tires and the engine can handle.
Its not the bigger tire that gets the car moving. In fact, when dealing with tires, bigger is ONLY better if you have gearing and/or traction issues. Otherwise, smaller tires are going to be better (notice my 4.30/26" comment). However, most of us don't have the resources to go changing gears and tires a lot, so we have to take our best guess. Knowing only what I read here, and assuming you don't care about the street, it is likely the 4.56/28" is the best choice. I could easily be wrong, and I'd certainly take into consideration what Chris is saying - been there, done that holds a lot of water in my book. He's also got a great point about making sure your current combo is optimized before changing things.
For reference, I run a 26" tire with 4.56 gears and am still somewhat under-geared for my power/weight. I go through the traps at ~112 mph @ 6500 rpm. My HP peak is 6100, though it drops off pretty hard after 6400 or so. Still, I'd like to add some more gear to help the early part of the track, and to hell with the finish line.
Good luck to all you guys.
Bob
I must first say that I wouldn't give my thoughts any more weight than any racers ideas concering tires/gears. They are simply my ideas based on my experiences, knowledge, and some assumptions. Please don't dismiss others out-of-hand. That said...
If your peak power is at 6500 rpm, then I'll likely want to go through the traps as high as humanly possible with that stock block. If that is 7000 rpm - cool, the higher the better. In simple terms (which is all I can really relate to anyways), that means as much gear as the tires and the engine can handle.
Its not the bigger tire that gets the car moving. In fact, when dealing with tires, bigger is ONLY better if you have gearing and/or traction issues. Otherwise, smaller tires are going to be better (notice my 4.30/26" comment). However, most of us don't have the resources to go changing gears and tires a lot, so we have to take our best guess. Knowing only what I read here, and assuming you don't care about the street, it is likely the 4.56/28" is the best choice. I could easily be wrong, and I'd certainly take into consideration what Chris is saying - been there, done that holds a lot of water in my book. He's also got a great point about making sure your current combo is optimized before changing things.
For reference, I run a 26" tire with 4.56 gears and am still somewhat under-geared for my power/weight. I go through the traps at ~112 mph @ 6500 rpm. My HP peak is 6100, though it drops off pretty hard after 6400 or so. Still, I'd like to add some more gear to help the early part of the track, and to hell with the finish line.
Good luck to all you guys.
Bob
Re: PAGING Bob Cosby----> Great info there guys.
<----nosey <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
<small>[ April 10, 2002, 05:44 PM: Message edited by: Lane ]</small>
<----nosey <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
<small>[ April 10, 2002, 05:44 PM: Message edited by: Lane ]</small>
