I've narrowed down the 2 tires I want to try: M/T 29.5x10.5 PBR & the Hoosier 29.5x10.5(R) with the 92.5 RO. I made final measurements yesterday with the current Hoosier 30X9(R) 92.5 RO tires. One set mounted on the 9" wide & the other on 10" wide rims.

I think I'll get the PBRs ordered today. The Boss Lady gave me the green light to get them ordered, LOL! I had testing scheduled for Fri & Sat in Bakersfield, CA. If need be I can go Sat & Sun & have the tires mounted Fri. Then I can do some tire comparisons/testing of a new tire for me.

PBR tires came in & mounted this morning. I mounted them on the 9" rims & they fit on the car good. They took 6.5 ounces & 8 ounces to balance, but it was slightly less than the Hoosiers that came off. The tires RO is 94.5"s & has a section width of 12.25 @ 17 lbs. I forgot to weigh the old set-up before dismounting, but can tell the PBRs are considerably heavier.

Leaving tomorrow for testing. Will baseline with the Hoosiers (21 runs) 1st, then with the PBRs.

if you want a real comparison...

1. it's takes more than one run to establish a baseline.

2. a control car that is deadly consistent needs to be in the other lane for every pass.

quote:

Originally posted by 1320racer:
if you want a real comparison...

1. it's takes more than one run to establish a baseline.

2. a control car that is deadly consistent needs to be in the other lane for every pass.

This is not a true comparison, just thought I would point out the differences in the test variances & there are plenty.

1. I have 400 + runs for a baseline on the Hoosier radials. I will baseline them with 2-3 runs before switching. Our car hasn't been to this track in 10-12 years. It's 2-3 tenths faster than our home track Vegas.

2. OK, I'll bite; Clue me in on 2!

3. I'm not going to get anal about this test. I'll provide some data & you all can read it or not.

4. In the end, the PBRs will be treated/tested primarily for 1/8 mile racing in preparation for the Pro 38 class @ the Spring Fling Million. If time permits this weekend, they will get tested in the 1/4 mile also. If I don't like them, I have the low run Hoosiers to fall back on or buy new.

OK, it was a pain testing this past weekend. Testing was primarily for up coming Nostalgia race with fuel cars. I wouldn't have towed for the cluster if I knew that.

All runs were made with a good amount of launch retard & added ballast. The typical way we slow it down to race.

I made run 1 & 2 on the Hoosier 30x9 on the 10" wide rims. I wanted to make one more pass with them, but I saw how the T&T was being ran. Nothing surprising, same performance. It ran mid 1.30 60's & a best of 6.310 in the 1/8 @ 108.06. The air was 750' & 880'.

The other 5 passes were on the PBR's. 4 were made on same day as the Hoosier runs & 1 the next day.

I haven't logged & crunched numbers yet, but there are differences that stand out.

#1 Weight the PBRs are 7 lbs. heavier ea. than the Hoosiers. This is according to the manufacturers, I haven't weigh them. Remember, I went to the 10.5 on the M/Ts.

#2 I lost of .03+ in the 60' & it continued with loses in the incremental times.

Here's a few other factors to consider. The best air on the PBRs was 1160' compared to the Hoosiers of 750' & 880'.

The remaining 4 runs on PBRs; air was 1450'-1580'

The PBR's are going to get more testing. Right now I see no advantage of changing from my Hoosier radials at this time.

Ran the PBRs this past weekend 15 runs total. Plain & simple, the track & weather was crap. The track was the brand new 4 lane/wide. So, we were seasoning lanes 1 & 2. The weather was cold & windy.

We started out with low mid to low 1.4 60's & as the track got better started running low 1.4s with the last run being a 1.404. While not the normal for the car. I was pretty impressed for the conditions.

We did pretty well & made it to the semi-finals & 2nd round out of 2 races.

Next weekend we are seasoning lanes 3 & 4 & have 3 races. I'll be running the Hoosier radials next weekend.

On a new track with no rubber down hard to fairly compare anything.

quote:

Originally posted by Curly1:
On a new track with no rubber down hard to fairly compare anything.

Exactly! Next weekend will be the comparison. I'm not knocking the PBRs at all, they hooked on less than ideal conditions. Plus, I was competitive on them. I'll be taking them with me next weekend because I know they work. The Hoosiers have treated me well, but are unproven on a virgin track.

If the Hoosiers work better (or worse), what will that tell you? You will be on a completely different racing surface that may be prepped better (or not as well) as last week's brand new surface.

quote:

Originally posted by Lenny5160:
If the Hoosiers work better (or worse), what will that tell you? You will be on a completely different racing surface that may be prepped better (or not as well) as last week's brand new surface.

Lanes 3 & 4 haven't been run on at all, just like we started with this past weekend on 1 & 2. The same prep will be done as this past weekend. This is one of the best tracks in the country.

I don't care what tire I use. They are not identical sizes & they are mounted on 2 different size rims. I'm looking for the combo that best fits my racing needs for any given situation.

After running both tires on green/new race track in similar conditions. I see no difference in consistency of the tires. The M/T's as stated earlier are about a .10 slower. I'm sure that's mostly due to them weighing 14lbs. more.

I'll be using the Hoosiers for the Spring Fling Million & use the PBRs for the remainder of the year for local points races.

Thanks for your info, the .10 for 7 lbs make sense to me.
I really think you will see the PBRs advantage with wear, they just last and last.