Gas and Tires

[the sandman]

OK one piece at a time. I picked up MT et drag slicks 26 10 15,s yesterday. New unused but old. I guess they are bias as no R anywhere. Very light. MT says tubes required but on tires it says 35psi max to set rim beads? I know that's alot of tire for my 280 3v but everything is 27 to 32 on FB and I have 4.10s. On the gas side, does anyone recommend octane booster or just use 93 for 11.5 to 1 na? The 93 is generally over a dollar more per gallon in Michigan so we are talking $15 plus per fill up. Thanks.

 

[the sandman]

I just checked with Summit and tubes are $90 plus each.

 

[MrBhp]

You'll spend 30 dollars to get 20 gallons of 87 octane to 93. That's not saving anything.

 

[JC SSP]

Even with inner tubes those are going to bounce and wobble. That’s a quarter mile race track only tire and not a street/strip tire. Be very careful driving with those, especially in the rain. Ask me how I know…

 

[Pentalab]

OK one piece at a time. I picked up MT et drag slicks 26 10 15,s yesterday. New unused but old. I guess they are bias as no R anywhere. Very light. MT says tubes required but on tires it says 35psi max to set rim beads? I know that's alot of tire for my 280 3v but everything is 27 to 32 on FB and I have 4.10s. On the gas side, does anyone recommend octane booster or just use 93 for 11.5 to 1 na? The 93 is generally over a dollar more per gallon in Michigan so we are talking $15 plus per fill up. Thanks.

The 05-10 cars are 9.81 CR. The 11+ cars are 11:1 CR. What eng do u have that is 11.5 CR ?

 

[07 Boss]

Octane rating has to do with resistance to detonation. If you go higher on the octane rating you can add more timing but if your not dialing in the timing it shouldn't matter.

 

[Midlife Crises]

A few notes about your ET Drags. They absolutely need MT enter tubes. The tires will not hold air by themselves. The MT tubes are thick and playable and will survive hard launches. Those tires will grow at speed and bounce when decelerating. The sidewalls are so flexible that cornering is risky until you learn their feel. Don’t even think about driving on wet ground. Period.
Short trips to town to show off are fun if the path is mostly straight hiway. I put 20 lbs in to run to town and 9 or 10 lbs on the drag strip. It is common to use a lock bead wheel or screw the beads to the wheel to prevent the tire form slipping in the wheel. Most folks don’t bother with balancing but I had mine balanced and they are very comfortable at the top end. Have fun!
This is a 28-10.5 X 15 all set up.

 

[Pentalab]

If inner tubes used, the beads need to be locked.....(both sides of both rears). If not, the rims will spin inside of the tires...and the valve stems will be sheared off.

 

[the sandman]

I got tires for strip only but don't want to drill holes in my new sve rims. Looks like it's another step forward and two steps back. Dang. Im wanting to stay NA so looking at possibly 12 to 1,s but after everything it will probably be close to 11+ to 1. ,,

 

[JC SSP]

I think you will be ok not screwing the tires to your rims. Usually that’s only done on high HP and high RPM launches with trans brake or clutch dumps. Paint a white stripe or use some duct tape on the rim and tire. Make a few passes, if the mark moves then your turning the tire on the rim.

 

[Midlife Crises]

Dedicated tires belong on dedicated wheels. Rip a valve stem out and you just might meet the wall. The drag strip is no place to screw around. Your local track may scrutinize your lug nuts more closely and require a driveline loop when running slicks.

 

[Pentalab]

With 9-10 psi on the rears, I can see it easily slicing off the valve stems if a bead lock is not used.

 

[stkjock]

speed cost money.... how fast do you want to go.....

also, why would you risk a $5000+ engine replacement to save some money on a fill up.............

 

[the sandman]

I want to go alot faster than I can afford. Im on here for help and experience. Want to know what others have used, and recommend. Man it's pricey to overhaul a 3v, but I do like the car.

 

[JC SSP]

It all depends on what you want to do with the car: track, race, autocross, street, etc... Also, what's your budget? Take it from someone who has been around racing for over 40 years... there are thousands of stories of 900HP+ dyno runs and sub 9-sec E/T trailer queens which all cost $$$$$$ and usually don't run as hard as expected and/or are more prone to breakage due to running on the ragged-edge.

Staying on the tire topic... I personally prefer a drag radial. They have a stiff sidewall, and the tread compound survives well under normal daily use and obviously DOT rated. Unless you're making a lot of power or launching super hard, these should suffix. I have run several tires over the years. Even before drag radials we're available… I had run real drag slicks with four grooves cut in them, so they looked DOT approved and even tried retreads which were a radial casing with a soft compound cap bonded on…

For drag/track specific I have used Hoosier Quick Times, McCrary Roadstars and M/T. All hook very well but bounce, float & wobble (from 10-20 psi). They are bias ply "gummy wrinkle wall" tires. I have run them without and with inner tubes and it still doesn't stiffen the sidewall enough for me to drive comfortably on the street for any long period of time. Also, if you're going to launch super hard, expect to start breaking stock parts too...

Again, and be forewarned, driving drag/track specific tires on the street when it's raining is dangerous!

 

[GriffX]

Octane rating has to do with resistance to detonation. If you go higher on the octane rating you can add more timing but if your not dialing in the timing it shouldn't matter.

On a charged engine I agree, but on a NA? VE stays the same, fuel mass also, does the 93 burns slower? My guess if you find that you can increase timing with higher octane, it wasn't optimal before too.

 

[Midlife Crises]

I have read many times that the Quick Times are very good tires but have never tried them. I have run MT and NITO drag radials, both tubeless. The MTs worked well on a prepared surface and ok on the street. They don’t like water. The NITOs were junk. Never hooked on the street, marginal on a prepared surface and wet or cold pavement could be deadly. If I remember correctly, the drag radials came with instructions not to screw them to the wheel.

 

[Laga]

On a charged engine I agree, but on a NA? VE stays the same, fuel mass also, does the 93 burns slower? My guess if you find that you can increase timing with higher octane, it wasn't optimal before too.

“Engine Masters” took a NA LS engine and tuned it for maximum performance on 87 octane. They then changed the fuel octane rating 3 times. 91, 100, 114, and tuned those for maximum power. Not only did all levels of octane produce the same amount of HP. The timing for max power remained the same. It depends on the design of the engine for how much HP it will produce.

 

[the sandman]

If you have a engine designed for 87, increasing octane usually reduces power. If you have a engine designed to run on 94 and run 87 you are going to have problems.

 

[GriffX]

Not only did all levels of octane produce the same amount of HP. The timing for max power remained the same. It depends on the design of the engine for how much HP it will produce.

So the increase in timing is basically the safety margin from factory?