Maybe I'm retarded and don't know what I'm doing. I have never had a more disappointing time at the track. I got my BF Goodrich Comp T/A Drag Radials mounted and balanced today, all ready to break into the 14's tonight. I have them mounted on my stock steel rims for right now. Well, the night went horrible. No where near 14's (at not what I'm used to). My times went like this:

D/R with 25 psi:

15.3136 @ 90.63 w/ 2.3579 60ft
15.2832 @ 90.85 w/ 2.3589 60ft
15.2207 @ 91.13 w/ 2.3377 60ft

D/R with 20 psi:

15.1257 @ 90.74 w/ 2.2899 60ft
15.3561 @ 90.81 w/ 2.5335 60ft
15.4088 @ 91.38 w/ 2.6016 60ft
16.1763 @ 79.33 w/ 2.6034 60ft (screwed up 2-3 shift)

17's with 40 psi:

15.1840 @ 91.38 w/ 2.3706 60ft

That's how my night panned out. I weighed the D/R on the steel rims when I got home and they weighed in at 38 lbs.! My 17's with tires weigh 35 lbs. I tried everything from a light spin just to clean them off, to smoking them and trying to heat them up. I tried waiting for the light and mashing the gas, holding the brake and raising the RPM's, etc. Nothing seemed to help. Does anyone know what I'm doing wrong or what the problem is.

 

What pressure?

Should have been in the low 20s.

 

I ran 25 the first couple runs, then dropped it to 20.

 

I have a pair of Nitto 205/45/15's 555r's and a pair of 22x8x15 M/T slicks and there is no comparison, gotta go slicks if you want the traction.

I wasted over $200 on them just to find out they aren't really much help.

BTW what size are the D/R's? Smaller will really help you out, especially N/A.

Jim

 

Jime's right about the tire comparison. another thing though, is i noticed about you lowering your psi. when you're out at the drag strip, (i've read this several places) you only want to keep lowering the psi back to what you first had it set at the first time. when you lowered it to 25, and then it probably went up after heating them up, lowering it from say 27 after they got heated from 25 down to 20, your tires are theoretically running as if they had 18 in them, not 20. so yeah, i usually just lower mine down to about 26-27ish (except i'm on decent 15" street tires), and keep adjusting it back to 27 or 26, so i don't throw psi way down and out of whack. plus, your tires will quit heating up and gaining even more after a bit anyways. you'll noticed it'll help a keep things a little more consistent. just a thought...

 

The reason I got drag radials is because at a couple drag events I've been to, slicks put you into the comp/race class instead of the street class. I had to wait a month to get these stupid things. I thought they would at least get better traction than my street tires!

My D/R are 205/50/15. Once I got them mounted I put them next to my 17's with 215/40/17 tires on and they aren't that much smaller around. Plus, they're heavier! I'm starting to think I just wasted $226.

 

Hey Jime,
how much did you pay for those slicks?

 

I think Mr. Confused runs his DR's in the teen's.. for PSI.. they almost look flat when he is in line..

 

I'll give it a try at lower PSI. They almost looked flat with 25 in them. Do you think the weight is a problem as well? I plan on getting some Millenia wheels in the future. Maybe that will help.

Who out there is running D/R and having good luck with them? What's your secret?

 

I don't think DRs or slicks are going to help an N/A automatic much if at all. Do you have a problem with spinning your street tires excessively off the line?

What was the situation with these, were you spinning them at all at the launch or just bogging. If you aren't spinning the DRs then DO NOT go with slicks. Not spinning the DRs indicates a lack of power, not lack of traction, meaning slicks would just make matters worse. You won't see a noticeable gain with lighter wheels either. People make alot of noise about this, I've made back to back passes with a 30lb rim/tire combo and a 37lb rim and tire combo, the lighter combo gave me about 1 tenth and 1 mph, nothing dramatic.

 

They were given to me after I bought the D/R's but they are pretty much the same price as the D/R's, $125-150 range. I run them at 10 psi and they are flat, have to really turn slow at the end of the track, I am afraid they will come right off the rims. Really takes off the top end too but more than makes up for that with a good 60'. Also they are much lighter than D/R's as well.

This is a cut and paste from one of my other posts on this subject.

I decided it was time to weigh my wheels.

I have two setups I use for racing both on same 15" alloy rims which weigh 19 lbs.

1. 205x45x15 Nitto 555R Drag Radials = 17 lbs.
2. 22x8x15 Mickey Thomson Slicks = 11 lbs.


Jim

 

Travis-

I don't think your VI is working in all the gears. Your car is making nearly as much FWHP and TQ as my 5 speed Maxima yet you're only getting 90-91mph trap speeds. I know you're an auto, but doesn't that sound a little low to you? I'd think you'd be getting at least 93mph in this cooler weather. Just for experiment, have you considered wiring the RPM switch without the relay like Cranman did? Last week when I tested my RPM switch running with the relay and the RPM switch only worked in 1st and sometimes in 2nd. It NEVER engaged 3rd. Sometimes the RPM switch light would go off, but the butterflys weren't opening. I now know you should be able to hear the butterflys open in all gears.

The stock steel rims aren't light. They weigh over 20lbs each, no joke. With FWD, you'll need to lower the drag radials to around 15-18psi and you've got to make sure they're warmed up with a decent burnout everytime.

I'd check out that RPM switch. If anything, at least change the way the RPM switch to connected to the relay. Don't have MAP's 12V wire going to the relay. Have the MAP's ground going to the relay and then wire the MAP's 12V to the battery (with a fused link).



Dave

 

I'll double check the switch. I can hear it kick in in 1st and 2nd. I need to pay better attention in 3rd, I can't remember wether I hear it or not. My indicator LED in the car comes on in every gear, so I know the MAP is getting power. I may try to come up with a way to set an LED up to come on when the actuator flips down and makes contact. It feels strong in every gear though so I don't know if this is the problem.

I was hoping to get a tire with a smaller circumference when I got D/R for my 15's. Unfortunately, they are almost the same. I'm not too up on the physics of the whole thing but I know that smaller cicumference tires will speed up quicker but now all I have is a tire with the same circumference, but is 4-5 lbs. heavier. (I hope circumference is the right word, it's been awhile since geometry.)

Dave:

Next time I come to the track up there I'll let you try'em out and see what you think. I asked people at the track last night how much wheel spin I was getting off the line and they said they couldn't really tell . Sometimes it took off hard and felt great and when I got the slip it'd be some 2.3-2.4 60ft. Other times it would bog a little.

 

Have any of you "slick" guys ever thought about putting some taller tires on the rear to jack the back up and put more weight on the front tires? I was thinking about using the stock 15" steel rims with 195/75-15's, their diam is 26.5" plus a smaller foot print than my 225's too? My slicks dim out at a 24.5" diam inflated, and when they are at race pressure I'm sure they are at least 1-2" less than that. So with this set up you could potentially jack the back ~2" higher than the front, this would help with the weight transfer. Add some rubber spring inserts in the back for another 1" or so and your set. Oh and 195/75-15's are only ~$50ea, and you can get them "S" speed rated

Any thoughts?

 

You are definitely having a power problem coming out of the hole....

If you can't tell if they are spinning or not...chances are that they aren't

The extra 3 lbs per corner with the DRs will not affect you much at all.....I'd venture to say that 3lbs doesn't do anything. I ran a 13 lb lighter rim/tire combo at the track last weekend...and I don't think it did much at all.

I'd check several things before you try blaming the Drag Radials

Make sure you flex section on your y-pipe isn't bunched up inside and check for a knock-sensor code (It doesn't trigger a CEL).

 

I wasn't 'blaming' the drag radials. I just expected more I guess. Thanks everyone for all the suggestions about things to check out or try next time. I'm not giving up on them yet.

 

Good luck!

 

I just did the math and the 215/40-17s are only 3% taller than the 205/50-15s. Also the extra weight is probably hurting the car too. The best solution is to run some lighter weight 15in wheels. If anything I could use those drag radials for my se-r. When you decide to sell them please PM me . If anything the DRs are probably giving you too much grip. You need either more stall rpm or less grip to get off the line better.

 

I do plan on upgrading my torque converter in the future. I'd like to wait until I have the funds to do an I30t tranny and high stall converter at the same time to save time and effort. I think with that set up I will be able to see better results with the D/R.

When does the "need" for more parts end?

 

New tranny? high stall torque convertor? In my opinion you should think about either swapping to a 5speed or selling your car and buying a 5speed max (or I30 like I did). Unless you are just dead set on having an auto tranny you should think about switching....I can assure you that your car will run a faster 1/4 mile than doing all of the above put together, it will be more fun to drive, and will give you some good use for those drag radials. But if your goal is just to break into the 14's for your 1/4 mile it looks like you are well on your way, that is a great time for any n/a auto max.

 

Call me lazy, but I don't think I'd like it having to shift all the time. I like it every once and awhile but day after day would get old for me.

Also, I like the road less traveled. I like the challenges it puts in front of me. I figure, for about $1500 I could have the tranny and torque converter. That's roughly the price of the 5-speed swap and I shouldn't be too far behind a lot of 5-speeds.

 

I pulled the codes today and what code popped up? 0304!! Also, a 1205 but that cause I use the resistor by-pass switch when I run at the track. I don't know how long it's been in there, but if I was running 15.1-15.2 at the track with a bad knock sensor, then I feel a lot better. Which is the reason for my other post in this forum about being able to set something up to visually "see" where your timing is at. 0304 won't trip the CEL by themselves so it would be nice to see right away when your timing is getting backed off.