[laynlo15]

Asking for a friend, if you already have HPT why would you need to have a draggy thingy. When I log I can see the times for a run from 40 to 120 plus all the other data I'm looking for on the pull. I suppose if you don't have HPT it's a useful tool. Just asking for a friend as I stated above.

[cjperformance]

Originally Posted by laynlo15

Asking for a friend, if you already have HPT why would you need to have a draggy thingy. When I log I can see the times for a run from 40 to 120 plus all the other data I'm looking for on the pull. I suppose if you don't have HPT it's a useful tool. Just asking for a friend as I stated above.

In short, mainly for fun and convenience. Its pretty cheap and really compact. Prob about 3/4" x 1" x 2" maybe guessing... I dont have to have my laptop with me to just play around. I can just grab it, throw it in the cupholder and start the phone app and it automatically starts recording different things.

Not sure if HPT can measure distance-based things like 60ft and 1/8 or 1/4 mile, but dragy can. Although i cant launch from 0 on the street so that functionality is limited usefulness for me. Some are successful like KingLT1 with that.

It isnt a major issue, but its GPS based too so it will not be thrown off by tire size changes or other things. Gives me DA and g force too. Although im somewhat suspect of the DA numbers., and g force is pretty squiggly. Would be nice if they showed a gforce average too. Not sure if that squiggly line is actually the variation in gforce on a run, or just some artifact of thier calcs.

For HPT, do you manually calculate a run, or is there a function you can set up to show those times automatically? If so, that would be helpful.

Dragy is not a requirement for tuning, but it is cheap, reliable, and just entertaining for me.

[laynlo15]

Originally Posted by cjperformance

In short, mainly for fun and convenience. Its pretty cheap and really compact. Prob about 3/4" x 1" x 2" maybe guessing... I dont have to have my laptop with me to just play around. I can just grab it, throw it in the cupholder and start the phone app and it automatically starts recording different things.

Not sure if HPT can measure distance-based things like 60ft and 1/8 or 1/4 mile, but dragy can. Although i cant launch from 0 on the street so that functionality is limited usefulness for me. Some are successful like KingLT1 with that.

It isnt a major issue, but its GPS based too so it will not be thrown off by tire size changes or other things. Gives me DA and g force too. Although im somewhat suspect of the DA numbers., and g force is pretty squiggly. Would be nice if they showed a gforce average too. Not sure if that squiggly line is actually the variation in gforce on a run, or just some artifact of thier calcs.

For HPT, do you manually calculate a run, or is there a function you can set up to show those times automatically? If so, that would be helpful.

Dragy is not a requirement for tuning, but it is cheap, reliable, and just entertaining for me.

Cool, didn't know much about them except a lot of people appear to be using them. There may be a way to do the 1/8, 1/4 but not sure about that. How much do they cost.

[cjperformance]

Originally Posted by laynlo15

Cool, didn't know much about them except a lot of people appear to be using them. There may be a way to do the 1/8, 1/4 but not sure about that. How much do they cost.

About $160.

[KingLT1]

Originally Posted by laynlo15

Cool, didn't know much about them except a lot of people appear to be using them. There may be a way to do the 1/8, 1/4 but not sure about that. How much do they cost.

The Dragy will do everything. It is dead nuts accurate with about every track they have been compared at.

Here is an example of the digital slip it gives you after a run.

[JimGnitecki]

Originally Posted by cjperformance

Got a much better 40-110 with the DRs. Im still feathering it in slightly at the start, but loads better.

Prev best was 6.49. So about a whole second faster.

You got about a whole second off the 40 to 110 mph time just by changing to the Nitto 555R2 tires? That is very impressive.

I am looking for a way to reduce the traction control effects I am getting on the street (not track or drag strip) with the OEM run flat tires with my Magnuson 2650.

Are you running OEM tire size in the Nittos? Or?

How wide can you go, or more realistically, how wide is appropriate with the stock LT1 suspension and fender clearances?

Will the Nitto 555R2 has reasonable ability to handle rain and cold temperatures? (MY car would not be used in really cold or really slippery weather)

How much tread life would I be giving up compared to OEM run flats or Michelin PS4S?

Jim G

[KingLT1]

Originally Posted by JimGnitecki

You got about a whole second off the 40 to 110 mph time just by changing to the Nitto 555R2 tires? That is very impressive.

I am looking for a way to reduce the traction control effects I am getting on the street (not track or drag strip) with the OEM run flat tires with my Magnuson 2650.

Are you running OEM tire size in the Nittos? Or?

How wide can you go, or more realistically, how wide is appropriate with the stock LT1 suspension and fender clearances?

Will the Nitto 555R2 has reasonable ability to handle rain and cold temperatures? (MY car would not be used in really cold or really slippery weather)

How much tread life would I be giving up compared to OEM run flats or Michelin PS4S?

Jim G

Fyi, The run I posted above was done on the street with a 305/35/20 Nitto 555r2 drag radial on the stock SS wheel...second gear launch. Best tire there is for the street period imo. The Toyo R888 is also good if you don't mind some noise. Run flats are crap for traction...I would spin those at 90mph. A 17" wheel with a 305/45/17 like CJ has would be even better.

[laynlo15]

Originally Posted by JimGnitecki

You got about a whole second off the 40 to 110 mph time just by changing to the Nitto 555R2 tires? That is very impressive.

I am looking for a way to reduce the traction control effects I am getting on the street (not track or drag strip) with the OEM run flat tires with my Magnuson 2650.

Are you running OEM tire size in the Nittos? Or?

How wide can you go, or more realistically, how wide is appropriate with the stock LT1 suspension and fender clearances?

Will the Nitto 555R2 has reasonable ability to handle rain and cold temperatures? (MY car would not be used in really cold or really slippery weather)

How much tread life would I be giving up compared to OEM run flats or Michelin PS4S?

Jim G

I run the same 305 35 20 555r2s that King runs and for sure a great street tire and dam good at the track also. Highly recommend them for any Boosted or NA Camaro with decent power. I actually ran them on my Camaro before we put the blower on. I've got them mounted on 20x9.5 Black Twisted split wheels. I followed a guy on you tube that got over 12,000 miles out of his R2s including some drag strip runs. So they where well and hook also. They have 6/32nds compared to 11/32 on my 555 G2s I run on the front. I've got about 3500 miles on my drag radials and still look new.

[laynlo15]

Are there more than one Manufacturer of the dragy? If so, what are people running?

[JimGnitecki]

Originally Posted by laynlo15

I run the same 305 35 20 555r2s that King runs and for sure a great street tire and dam good at the track also. Highly recommend them for any Boosted or NA Camaro with decent power. I actually ran them on my Camaro before we put the blower on. I've got them mounted on 20x9.5 Black Twisted split wheels. I followed a guy on you tube that got over 12,000 miles out of his R2s including some drag strip runs. So they where well and hook also. They have 6/32nds compared to 11/32 on my 555 G2s I run on the front. I've got about 3500 miles on my drag radials and still look new.

Ok! The OEM run-flats on my LT1 are 245/40ZR-20, so nominally the 305 Nittos would be (305-245) = 60 mm wider = 2.36 inches wider, so would intrude an extra 1.18" on each side, towards the suspension, frame, and fender parts.

Are the 3-dimensional areas around the rear wheel assembles identical on the LT1 and the SS?

Jim G

[JimGnitecki]

Just another sanity check:

My OEM 245/40-20 tires have a nominal sidewall height of 245*0.40 = 98mm.

The 305/35-20 Nittos tires have a nominal sidewall height of 305 * 0.35 = 106.75 mm

The extra height of only 8.75mm is I am sure inconsequential from a clearance perspective.

BUT, the 106.75 sidewall height creates a tire with a nominal diameter of:
20 + 106.75/25.4 + 106.75/25.4 = 28.0 inches

The OEM 98mm sidewall height creates a tire with a nominal dimaeter of:
20 + 98/25.4 + 98/25.4 = 27.7

This makes for a modest 28.0/27.7 -1.0 = 1.1% unintentional gearing change (1.1% "taller" gearing). That is not enough to upset the ECU when either the ABS system or the traction control system compares the OEM front tire rpm with the Nitto rear tire rpm, right?

Jim G

[KingLT1]

Originally Posted by JimGnitecki

Ok! The OEM run-flats on my LT1 are 245/40ZR-20, so nominally the 305 Nittos would be (305-245) = 60 mm wider = 2.36 inches wider, so would intrude an extra 1.18" on each side, towards the suspension, frame, and fender parts.

Are the 3-dimensional areas around the rear wheel assembles identical on the LT1 and the SS?

Jim G

You need a SS wheel like Laynlo did on his LT1 then you can move up to a 295/35/20 or 305/35/20 max. Some will say it's too wide for a 9.5" wheel but it works because Nittos tend to run a little narrow . Or get a set of 10.5" wheels. I believe the max you can run on your LT1 8.5" wheels would be the 275/35/20 555r2. It will be a lot better then what you have now.

[MartinLe]

Originally Posted by laynlo15

Are there more than one Manufacturer of the dragy? If so, what are people running?

Nope. Dragy is the only manufacturer.

[JimGnitecki]

Originally Posted by KingLT1

You need a SS wheel like Laynlo did on his LT1 then you can move up to a 295/35/20 or 305/35/20 max. Some will say it's too wide for a 9.5" wheel but it works because Nittos tend to run a little narrow .

Aw, nuts. I love the 20" black painted wheels with red accents that come with the Redline package - prettiest and easiest to clean wheels I have ever owned. Plus, a pair of SS wheels would be pretty costly I imagine.

:(

Jim G