28" Tires?
#1
28" Tires?
I'm planning on shifting my 6 speed c5 with stock 3.42 gears and a 416 stroker at 6800-7000rpm and was wondering if it is more efficient to run a 28" tire and run to the top of 3rd gear or run a 26" tire and shift into 4th right before the traps. Will I lose a lot on the 60' because of my stock gearing with the 28" tires?
#3
Melting Slicks
If you're sure you can make it through in 3rd then run the 28" tire. You shouldn't loose 60' because you'll have more traction and you can make up for it in launch RPM.
#4
If you shifting is really bad, go with the 28" tall tire so you don't have to make that extra shift. If not, the effective gear ratio change and slightly lighter weight from the 26" will be beneficial.
#5
Le Mans Master
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You would be best served with a 26" tire to maintain your current effective gear ratio. The correct tire will provide you with a better 60' and get you to your powerband quicker. (26s can produce 1.4 60s with your current gearing.) In the future, you should strongly consider a gear swap. Our cars with a 4.10 ring and pinion perform exceedingly well in a N/A setup. This is with both 26" and 28" tires. Tire height would be dictated by trap speed and rpm.
#6
Melting Slicks
You would be best served with a 26" tire to maintain your current effective gear ratio. The correct tire will provide you with a better 60' and get you to your powerband quicker. (26s can produce 1.4 60s with your current gearing.) In the future, you should strongly consider a gear swap. Our cars with a 4.10 ring and pinion perform exceedingly well in a N/A setup. This is with both 26" and 28" tires. Tire height would be dictated by trap speed and rpm.
OP, what's your current power and splits at the track? Maybe we can stop guessing and help you a little more.
#7
The car is currently making 450rwhp with a small cam 416 stroker, shorty headers, and a FAST 78mm intake. I am building it right now with a larger cam, long tube headers, and a fast 102 setup and hoping for around 500rwhp. I've never had it at the track yet because I need to buy drag radials first so I was contemplating 28" tires instead of spending the money twice
#8
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I am just trying to compare apples to apples for the OP based on experience. All of the N/A Vettes with manual transmissions that we have ran or help design have benefited from a gear change. It gives you torque multiplication off of the line and will place you in a better rpm range at the end.
#9
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The car is currently making 450rwhp with a small cam 416 stroker, shorty headers, and a FAST 78mm intake. I am building it right now with a larger cam, long tube headers, and a fast 102 setup and hoping for around 500rwhp. I've never had it at the track yet because I need to buy drag radials first so I was contemplating 28" tires instead of spending the money twice
Here are different combos that work:
315/35R17 Hoosier DR
1.44
255/50R16 Hoosier DR
1.45
26x12x16 Bias Ply M&H Slick
Three consecutive passes made with 1.41, 1.35, 1.38 60's, respectively.
26x11.50x16 Bias Ply MT ET Street
Pass #3- 1.40
28x11.50x16 Bias Ply Hoosier QTP
1.38
#13
Melting Slicks
Nice, job on documenting all of those different tires for drag racing. It very obvious to see how much better the car accelerates and carries forward momentum off the line using the bias ply tires. What clutch and flywheel is in the car Gary?
#14
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We have ran the RPS BC2 with an aluminum flywheel from the start once we began the mod process. It has seen some R&D along the way to enhance its already great performance. A new iteration is in the works for the most recent round of mods.
#16
Captain huff and Gary are experts and successful so I agree yet for slower shifters like myself and with M12 trans at that power level actually staying at top of 3rd would benefit ; I lose 3 tenths shifting into 4th in my set up and my self ; this will actually edge out for bracket racing especially in warmer days ; in lower elevatiom lower DA for personal best I would lean towards smaller tire and let 4th spread;
If it's mm6 trans and you can shift well into 4th( these 2 things go hand in hand with powerband/shift point) then 26" tire for sure ; assuming shift point at 7000
If it's mm6 trans and you can shift well into 4th( these 2 things go hand in hand with powerband/shift point) then 26" tire for sure ; assuming shift point at 7000
#17
#18
AMP Racing
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2023 C5 of the Year Finalist - Modified
2017 C5 of Year Finalist
St. Jude Donor '09-'10-'11-'12
Pull the liner out and a 28" slick will fit.
According to M/T tech, a 28" slick will grow to 29.5" at 150MPH.
The issue with a C6Z is the rear end gear ratio. Unless you're making a boatload of power, a 26" tire is likely best due to the gearing advantage.
Have fun with your goals!
According to M/T tech, a 28" slick will grow to 29.5" at 150MPH.
The issue with a C6Z is the rear end gear ratio. Unless you're making a boatload of power, a 26" tire is likely best due to the gearing advantage.
Have fun with your goals!