24.5" slick better than my bfg's

[cochino12]

A friend of mine gave me some m/t 24.5" slicks to run on sunday. My question is will I be better of using my bfg's since they are about 2" taller? I am getting the 4:10 installed and think that might run out of gear and spin too much with a tire that short.

[Jonboy]

24.5 seems awfully short. I would stick to the taller tire with 4.10's.

[MylilBowTie]

I would run the slicks, heat them up and see what happens. I dunno what type BFGs you have but I dont think it would hurt to try the slicks even tho they arent very tall.

[gldevall]

You do have 4 gears, so try the slicks. What's it gonna hurt?

[ocbaud]

maybe launch in second and see what that does

[raceman6135]

If you are having brand new 4.10:1 gears installed, you'll have to break them in over approximately 500 miles before you take it to the track.

With regard to the tire sizes, you should calculate what your RPM will be at the end of the track (either 1/4 mile or 1/8 mile), and compare that RPM to your engine specifications. We know nothing about your engine. If it's a worn out 305, chances are good that the weak valve springs are going to stop you from revving past 4000 RPM anyway, so going to a shorter tire is going to be murder.

As ocbaud suggested, you can 'cheat' the engine by leaving in second gear, and then short-shift to third, thereby keeping RPM in a safe range. Your ET will be crap, but what kind of racing are you doing on Sunday? If it's brackets, it doesn't matter how low or high the ET is, as long as it's consistent.

You also didn't say anything about the width of either tire, or which compound is in the M/T slick. If the M/Ts are drag slicks, there's a good chance your engine will bog with the new-found traction.

Can your truck spin the tires now? Is there a posi/locker going in with the 4.10 gears? What gear is in there now? If the truck can't spin the tires now, and if it has (for example) 3.73:1 gears, going to the 4.10s is not that big of a difference, and simply airing down the BF Goodrich tires and adjusting your starting line RPM will reduce or eliminate spin.

Sorry, but it's kind of difficult to be more helpful when we don't have more info.

DJS

[TIMSPEED]

24½" Slicks, sounds like they're slicks for imports. Personnally, if it were me, I'd run a 26" Tall tire, with a 3.73/700R4 setup. Hell, in my vette, I run a 26" tall tire with a 3.07/700R4 and it's DEAD PERFECT. Of course, my intake doesn't breath above 5000rpm, whereas I'm SURE yours is good to 6500rpm, so I'd say get a set of 26"x11½" E/T Streets.

[cochino12]

Originally Posted by raceman6135

If you are having brand new 4.10:1 gears installed, you'll have to break them in over approximately 500 miles before you take it to the track.

With regard to the tire sizes, you should calculate what your RPM will be at the end of the track (either 1/4 mile or 1/8 mile), and compare that RPM to your engine specifications. We know nothing about your engine. If it's a worn out 305, chances are good that the weak valve springs are going to stop you from revving past 4000 RPM anyway, so going to a shorter tire is going to be murder.

As ocbaud suggested, you can 'cheat' the engine by leaving in second gear, and then short-shift to third, thereby keeping RPM in a safe range. Your ET will be crap, but what kind of racing are you doing on Sunday? If it's brackets, it doesn't matter how low or high the ET is, as long as it's consistent.

You also didn't say anything about the width of either tire, or which compound is in the M/T slick. If the M/Ts are drag slicks, there's a good chance your engine will bog with the new-found traction.

Can your truck spin the tires now? Is there a posi/locker going in with the 4.10 gears? What gear is in there now? If the truck can't spin the tires now, and if it has (for example) 3.73:1 gears, going to the 4.10s is not that big of a difference, and simply airing down the BF Goodrich tires and adjusting your starting line RPM will reduce or eliminate spin.

Sorry, but it's kind of difficult to be more helpful when we don't have more info.

DJS

You are right I should have posted more info, I get used to the same guys answering posts and assume everyone know most everything about everyone's trucks. I have a zz4 witha bout 10k miles, as far as the racing I'm just going to make a few passes dont really care about winning anything just want to break into the 14's (15.4 previous). I'm not too sure about the tires except they are for a 15*10 rim. I can roast the tires pretty good now running 3:73 gears and an eaton posi. My bfg's are comp t/a's that hook pretty well, but who couldnt use more traction right . thanks for any input

Originally Posted by TIMSPEED

24½" Slicks, sounds like they're slicks for imports. Personnally, if it were me, I'd run a 26" Tall tire, with a 3.73/700R4 setup. Hell, in my vette, I run a 26" tall tire with a 3.07/700R4 and it's DEAD PERFECT. Of course, my intake doesn't breath above 5000rpm, whereas I'm SURE yours is good to 6500rpm, so I'd say get a set of 26"x11½" E/T Streets.
TIMSPEED

What does your vette run? Not much faster than your truck right? tpi? just curious.

[TIMSPEED]

Originally Posted by cochino12

What does your vette run? Not much faster than your truck right? tpi? just curious.

Well, haven't had the truck to the track...but the vette runs 13.0@104mph, with a 1.75 60'. (255/50 16" BFG Drag Radials) All Stock sans Headers & Exhaust, 2600rpm Stall Converter, TPI yes.

EDIT: I'd run a TALLER tire than a 26" with a 3.73/700R4, because with a 3.06 1st Gear COUPLED with a 3.73 REAR gear, those tires are gonna wanna SPIIIN. If you put a TALLER tire, then for each spin of the tire, you'll get farther down the track...honestly, I'd try a 28" FULL SLICK. Air it down to 15psi, heat them up good and see if you can't cut a 1.8 60'.

[cochino12]

HA HA HA I just looked at the tires and they are 26" tall guess I should have looked myself instead of listening to what he said.

[TIMSPEED]

Originally Posted by cochino12

HA HA HA I just looked at the tires and they are 26" tall guess I should have looked myself instead of listening to what he said.

With a 26" tall tire/3.73 gear/700R4, that SHOULD be perfect. But your first gear is gonna go QUICK. What is your stall converter at? 2500+? If you can get NO wheelspin, then your truck should scoot quite well. I know LT1 Vettes with just 26" DR's/3.73 gears/700R4 that go mid 12's...in mile high air in a truck, I would say High 13's/Mid 14's.

[81shavedtrk]

I run a 28 in tall tire with 4.10 gears and trip the lights at 6500 with my big converter and 5500 with street verter at 110mph. If you are using 373 and 700r4 don't shift out of 3rd, you won't need to. Let us know what you run at the track.

[cochino12]

Originally Posted by TIMSPEED

With a 26" tall tire/3.73 gear/700R4, that SHOULD be perfect. But your first gear is gonna go QUICK. What is your stall converter at? 2500+? If you can get NO wheelspin, then your truck should scoot quite well. I know LT1 Vettes with just 26" DR's/3.73 gears/700R4 that go mid 12's...in mile high air in a truck, I would say High 13's/Mid 14's.

I dont think I'll be anywhere near a 13 anything. I think I need way more carb to get down to the 14's. What size carb is your friend running on his zz4?

My stall is 2400 and I'll have 4:10 this weekend not the 3:73

[TIMSPEED]

Originally Posted by cochino12

I dont think I'll be anywhere near a 13 anything. I think I need way more carb to get down to the 14's. What size carb is your friend running on his zz4?

My stall is 2400 and I'll have 4:10 this weekend not the 3:73

2400 stall is probably fine. My friend is running a 750cfm Holley Single Pump.