Slicks vs MT ET Street radials

[89 coupe]

I currently am using the stiff sidewall 28-10.5-15s MT ET Drags with a totally stock front/rear leaf spring suspension and I have been 1.34 60' times only when the sun is off the track for several hours and when it's hot out and sunny I have mid/high 1.40s but I have Cal Tracs to put on over the winter. I want to try some MT ET Street radials but I have heard to opposite things about them. I heard they hook better than ET Drags because the compound is softer but I also heard they don't hook as well and I don't know what to believe. The way my car sits, it likes NO sidewall flex at all on launch and I have mine at 16PSI WITH tubes and it can put that initial "hit" directly to the track otherwise the sidewalls absorb too much and the launch is "mushy" and the front doesn't come up. With 14PSI the left rim tries to slam itself into the pavement by wadding up the slick. I don't know what the right one does but I assume it's doing the same. I had to screw them to the rims after they started spinning on the rims destrying the M/T tubes even with 18PSI(non stiff sidewall ET Drags before I bought the stiff sidewalls)I guess the question is: Will ET Street radials be as good or close to what the ET Drags are in the traction dept since I am using Cal Tracs next year? Would they be good with my stock suspension? Do they require a different burnout than the ET Drags do? I have QA1 adjustable rear shocks on it now (didn't help compared to the stock gas shocks) and will be using them with the Cal Tracs. I would like to run some true "street" classes next year since I already drive it on the street and it's tagged/insured/inspected and haven't been ticketed for driving it on slicks yet.

Thanks in advance

[DOTracer]

The only way to know is to try them. I currently run a 275/60 M/T and feel they are a very good tire. Maybe not bracket race consistent in the 60', but overall they are a killer tire if your car is setup well.

I run a stock suspension '79 Malibu with an iron headed bbc, 55% of the weight on the nose, 3515 lbs. Footbraking the car runs low 10's with a 10.03 best so far with a 1.395 60'. That's with 18-19 lbs of aire pressure in the 275's on a 9.5" wide rim.

If you wish to stay with the 28" tall, your options are the 275 tire which is rated at around 9" of tread or a 325 which is rated at 11" of tread. Measuring the actual tread stick portion, my 275's show they are closer to 10" or a little more of rubber actually on the ground. The sidewall seems to lay down flat and becomes part of the tread as it wraps around the side...soft stuff picks up brass and rocks on the rounded edges of the tread/sidewall.

Keep in mind that the radial does not grow with mph, so your rpm's may increase over a bias ply tire.

I myself do a very short burnout...like 5 seconds or less. Any more and it seems to just wear rubber off and be of no benefit to the 60'. The tread is quite soft. I'd swear on hot days if the tires were completely clean I could probably stage without a burnout.

BTW, that 1.34 60' of yours is killer. Is that N/A or a power adder? What kind of ET/mph and what weight vehicle?

[Jim Filipowski]

The side walls on the radials are real stiff even compared to the stiff side wall slicks/et streets. I have never A&B the tires, But I know that the radials will wheelie more than et streets/slicks do to the side wall construction. M/T radials do have a killer rubber compound, They work well with a long or short burnout.

[matt mcarthur]

i switch back and forth between the 28X10.5S's and 325 radials and my 60' are more consistant with slicks but if the track is right i've cut as good as a 1.28 with the radials... i'll 2nd what powski said as they do like to wheelie more than the slicks when they hook up.

[89 coupe]

The only way to know is to try them. I currently run a 275/60 M/T and feel they are a very good tire. Maybe not bracket race consistent in the 60', but overall they are a killer tire if your car is setup well.

I run a stock suspension '79 Malibu with an iron headed bbc, 55% of the weight on the nose, 3515 lbs. Footbraking the car runs low 10's with a 10.03 best so far with a 1.395 60'. That's with 18-19 lbs of aire pressure in the 275's on a 9.5" wide rim.

If you wish to stay with the 28" tall, your options are the 275 tire which is rated at around 9" of tread or a 325 which is rated at 11" of tread. Measuring the actual tread stick portion, my 275's show they are closer to 10" or a little more of rubber actually on the ground. The sidewall seems to lay down flat and becomes part of the tread as it wraps around the side...soft stuff picks up brass and rocks on the rounded edges of the tread/sidewall.

Keep in mind that the radial does not grow with mph, so your rpm's may increase over a bias ply tire.

I myself do a very short burnout...like 5 seconds or less. Any more and it seems to just wear rubber off and be of no benefit to the 60'. The tread is quite soft. I'd swear on hot days if the tires were completely clean I could probably stage without a burnout.

BTW, that 1.34 60' of yours is killer. Is that N/A or a power adder? What kind of ET/mph and what weight vehicle?

That is some great info, thanks! They sound like they should work good similar to the ET Drags I have now but less consistent.

I have an 8.5" wide rim so it is a little narrower than it should be for the 28x10.5s so I think the 275-60-15s would be about right for me until I get some new wider rims with the correct offset and width for the 325s.

My car is N/A but I would like to put a small 150-175hp nitrous system on it next year. I run it at a local dragstrip at the Nascar sanctioned asphault oval but thye have a tenth mile NHRA sanctioned track on the front straight so it is very unique but very fun. Launch, shift to 2nd and cross the traps. I only went 2 times to the 1/4 mile track in late July and had problems with fuel delivery surging and going flat in late 2nd and thru 3rd gear (fuel filter clogged with rust and gas cap not vented causing heavy vacuum) plus that was with the exhaust system on so it ran 10.20s with a best of 60'-1.34 1/8 mile-6.50 at 104 1/4 mile-10.21 at 129. With good cold air this weekend, good CLEAN free flowing fuel filter, and uncapped headers it should run in the 9s hopefully if the converter can handle the power and not go away. It currently weighs 3130 w/o me in it and 3290 w/driver and 5 gallons fuel. I am running 235/60/15 front tires so I can hold it on the line when foot braking for max suspension pre-load.

[89 coupe]

The only way to know is to try them. I currently run a 275/60 M/T and feel they are a very good tire. Maybe not bracket race consistent in the 60', but overall they are a killer tire if your car is setup well.

I run a stock suspension '79 Malibu with an iron headed bbc, 55% of the weight on the nose, 3515 lbs. Footbraking the car runs low 10's with a 10.03 best so far with a 1.395 60'. That's with 18-19 lbs of aire pressure in the 275's on a 9.5" wide rim.

If you wish to stay with the 28" tall, your options are the 275 tire which is rated at around 9" of tread or a 325 which is rated at 11" of tread. Measuring the actual tread stick portion, my 275's show they are closer to 10" or a little more of rubber actually on the ground. The sidewall seems to lay down flat and becomes part of the tread as it wraps around the side...soft stuff picks up brass and rocks on the rounded edges of the tread/sidewall.

Keep in mind that the radial does not grow with mph, so your rpm's may increase over a bias ply tire.

I myself do a very short burnout...like 5 seconds or less. Any more and it seems to just wear rubber off and be of no benefit to the 60'. The tread is quite soft. I'd swear on hot days if the tires were completely clean I could probably stage without a burnout.

BTW, that 1.34 60' of yours is killer. Is that N/A or a power adder? What kind of ET/mph and what weight vehicle?

That is some great info, thanks! They sound like they should work good similar to the ET Drags I have now but less consistent.

I have an 8.5" wide rim so it is a little narrower than it should be for the 28x10.5s so I think the 275-60-15s would be about right for me until I get some new wider rims with the correct offset and width for the 325s.

My car is N/A but I would like to put a small 150-175hp nitrous system on it next year. I run it at a local dragstrip at the Nascar sanctioned asphault oval but thye have a tenth mile NHRA sanctioned track on the front straight so it is very unique but very fun. Launch, shift to 2nd and cross the traps. I only went 2 times to the 1/4 mile track in late July and had problems with fuel delivery surging and going flat in late 2nd and thru 3rd gear (fuel filter clogged with rust and gas cap not vented causing heavy vacuum) plus that was with the exhaust system on so it ran 10.20s with a best of 60'-1.34 1/8 mile-6.50 at 104 1/4 mile-10.21 at 129. With good cold air this weekend, good CLEAN free flowing fuel filter, and uncapped headers it should run in the 9s hopefully if the converter can handle the power and not go away. It currently weighs 3130 w/o me in it and 3290 w/driver and 5 gallons fuel. I am running 235/60/15 front tires so I can hold it on the line when foot braking for max suspension pre-load.

[89 coupe]

They have a tread pattern that looks directional. Can you swap them side to side like you do with slicks when they get feathered pretty heavy or is the tread or tire design prevent you from doing that? What is a typical gain in 1/4 mile MPH compared to bias ply slicks at around 130-135MPH? How quick do they wear compared to ET Drags? I am really liking the idea of using drag radials more and more. I just with MT made more sizes for 28" tall sizes for 15" rims than the current selection. I want inbetween the 275-60-15 and the 325-50-15. Actually, a 295-55-15 or 305-55-15 would be just right for me. I can fit a 29" tall tire in there if it doesn't grow more than a half inch but I have been using 28-10-15 ET Drags on this car since the early 90s. I did put a set of 225-75-16LT tires (29.3" tall) on the rear for the NY state inspection and they barely cleared the front/rear wheel wells. I am restricted on the width so the 275-60-15 DR is my only real choice when the slicks get worn down.

Thanks for all the info guys!