Drag Racing Discussions > Front Engine Dragsters

calming the car down on the starting line

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masracingtd1167:
Both Chris and Dave are right about checking the frame and swapping the tires and I would do the same ! Did you add some weight to the front ? Did you drop your tire pressure It should give you some more wheel speed ! Those 10.5 tires are very aggressive and it is hard to get wheel speed with them ! How about taking some timing out like 28 degrees ! How close dose Chris wide open live to you ? See if he could come to the track with you ! I had a similar problem when I tried a different tire on mine and I just could not get the car to go straight went back to my 2585 Goodyears and the car was perfect !

wideopen231:
If you are running Farmington I am about 45 minutes away. Just need cpl days notice and next two Saturdays are booked.Its muzzleloader and my family know not to die during those two weeks or Chris will not be there. Now if your doing midday so I can leave out around 3:30 and be in my stand come 5 o clock I am willing to help out.

Now Bill has me worried about my MT's on FED,bt then those who know me know getting wheels speed has never been my problem.Too much maybe.LOL

JrFuel Hayden:
Crider , I have benn following your posts, and I may not have THE answer, but here are a couple of my thoughts;
I assume your chassis and rear-end set-up is good since your car was going straight before, with no chassis changes, just more power ?
But again check the roll out of your slicks, and try swaping tires to see if it still turns right at about 30' .
If it was my JF car I would add at least 40 lbs to the nose if you are getting a quick yank of the front wheels at the hit, that might be adding to your problem if you have a short or stiff wheelie par.
My WB is a 5 foot 3 bar CM with no connectors between the bars, so I get some flex in the WB , a stiff WB will only make your problem worse when the WB hits.
Again , if it was my car and I added pressure to the right tire and it still goes more right, I would think it means the right tire is spinning more so the left slick steers the car to the right.
I notice you and a few other racers are using the M/T 33x10.5x15 tires, and just so know all the 10.5 tires were built for the 10.5 door car classes, where the cars weight 2-3k+ and shift allot more times than your PG , which means the sidewalls are stiffer, and softer compounds for better traction. Where as FED 2 speed cars want/need enough tire spin the keep the engine at it's HP RPM range.
I have tried the MT 33x10.5 a few times on our 1450lb [ with driver] Heritage all iron JrFuel car, mostly because a buddy of mine could not get them to work on his Heritage A/F car, mostly because he was looking for more tire growth , because it was a a stiffer side tire he did not get what he wanted. With our JF car we did get a bit better 60' times, but the GY 31x12x15 gave us better ET's, AND it drifted to the right, probly not the reason you are going right.     
What I would do if it was my car is keep adding front weight until the front wheels don't come up, raise the WB up to 2-2.5 "  check roll-out, check for chassis cracked or broke tubing [ we have cracked tubing from tire shake] try different launch RPM, or leave off the foot brake and tire pressures [ MT suggests 7-7 .25, but i see some guys are running 5-5.25, but check to see how fast they are running]. One thing that helped our 7.0's 186-189mph car is changing to a 1.69 first gear so it will not hit the tires so hard, and I run a looser converter [ 8500 rpm] that also helps not hit the tires so hard.
About converters, your car will improve when you get the converter to cloer match you engines power range. example your converter is stallin/ flashing at 6.2k but if you engine "come-on" at 7k she wil struggle for 1000 rpm. best way to get the right converter is to dyno your engine, if that's not possible ball park idea is it should stall about 1000-1500 below your shift RPM.
Another idea is to aim your GoPro camera at your tack to play back the goPro to see what the RPM drops to right after the shift [ which is your true stall rpm].
This is no dought too much info, so feel free to call me , 805-444-4489, cell
Jon     

crider:
Thanks Jon for all the info, seems like a few more Ideas to try. I have dropped the air down to 6psi. Haven't added a weigh bar yet, as lowering the wheelie bar got all the crazy launches under control, now it is just a slow push to the right instead of the I wonder which way it's gonna go this time action that I had going on.  I'll pull the tin back off and give everything a good check before the next time I go out. I had it all off when I was centering the wheelie bar, but didn't really check it closely. As for the converter, it was set up as a 6400 stall, and I'm shifting at 7200. But haven't been paying attention to the rpm drop to know the true stall speed. I really need to get this thing to run straight. I've had my hilborn setup back from Spud for a while now, but I want to have the car acting right before I open another can of tuning worms...lol I guess next time out I will switch the tires around. I don't think it is a lack of being in the groove, since it has done almost exactly the same thing 6 passes in a row and at 2 different tracks. after a quick slap of the throttle it goes as straight and smooth as you could ever ask for. I just need to fix the first 60 ft of the run.
Chris  if I haven't got this thing figured out by the end of hunting season I may have to take you up on the offer to help out. I could use a good pair of eyes on the outside of the car too

wideopen231:
Let me know. 336 362 1785.Heck I love tuning a car more than driving anyway and little FED experience might payoff if my junk ever gets something to ride on to get it to track. Plus I have a go pro that will give recording thats better than old guys eyes,it rewinds.LOL

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