About 6 weeks ago I registered for the class. Its much less if you bring your own car and I feel I dont really need any schooling on how to drive just some one on one and maybe tips and tricks for going as fast as this car is capable of. Doing a normal TnT theres usually no one around to spot the car let alone take up close detailed vids of the run to review later. There was about 15 students in the class ranging in age from mid 20's up to the 70's some with exp and other total newbs The class is broken up into 6 runs. 1, 60' if you do ok on that then you go to 200' after that 1000' and the next day 3, 1320' licensing passes. The Skyhawk did exactly what she was supposed to up until the time I let go of the button. This was the first hit where its hooked and didnt break stuff. After that it went south fast. Car pulled a 3-4' wheelie, hit the bars then unloaded the suspension and made a hard left while being all sorts of out of shape. Steered out of it and shut down at the designated marker for 60'. Needless to say I failed that and had to do it again. After a review of the tape and discussion of everyone's runs the class headed out for a second pass. I lowered the wheelie bars to 3" off the ground and dropped the launch RPM from 4600 to 3800. The run was basically the same with the exception of only being a 2' wheelie. After the review of the second run Frank pulled me aside and said the car was to dangerous to continue and it needs some suspension work. Offered me a full do over for free at a later date. Frank has a suspension guy, Jimmy, on his staff that works on and sets up the cars they use. His cars go perfectly straight as long as the students steer them correctly. Really dont think the stock crate 572 BBC they use is making the power the Tomahawk makes. So I got with him and we looked at the car together and his opinion is the rear suspension needs to be reworked. The geometry of the wheelie bars and 4 link are out of whack. He could see it but to my untrained eyes could not really tell. Anyway its something that could not be done on site. First thing he said to me " I watched the runs and man that thing is violent when it leaves". During the first review session in the class room Frank asked me how I thought the run went and I answered Awesome!, I call it a win. the car didnt break and I didnt crash. Not the answer he was looking for.
So, how many "Depends" did you go thru? 2 I assume.. Your next step here is to do your homework.. go hang at the local speed shops, machine shops, and the track, and talk to the guys that have good working fast cars, and get a recommendation for a chassis shop that will steer you right. Don't be surprised if the first tool they recommend is a sawsall to cut out what's there, and start over with a more up to date rear suspension setup. Over time, chassis mounting points can move. Plus the latest setups have 1/2 mounting holes instead of 3/4, and a lot more of them. This allows more adjustability. Hawley's guy might have looked at it, and just did not want to get into it, or he looked at it and thought " can't get there from here".. we don't know unless he told you. Hopefully the car can be squared, and weighed, and relatively minor adjustments/modifications can be done to get it to go straight. I can tell you for sure that if that car does have an anti-roll bar, it needs one. Anti-roll bar technology has revolutionized drag racing 4 links in the last 20 years or so. Buy yourself a set of wheel scales.. they used to be a major purchase, 4-5 of my racing buddies went in on a set back in the late 90's, because they were expensive back then.. 4-5k as I recall... but today they are relatively inexpensive. And they are wireless. which is wonderful. You will be using them to check the cars wheel weights regularly, you would be surprised how much they can change, all by themselves. I have seen a dry, binding heim joint change the weight on the LF wheel by over 100 lbs. And be patient... Rome was not built in a day. The Good news is that once you get all the kinks worked out, your going to have one hell of a fast car. JW
Speaking of books, Dave Morgan's book is considered "the bible" for Door cars. Not sure how up to date it is, as it was written a long time ago, but the basics have not changed, and that's what you need to understand. Even if you hire someone else to do the work, you, as a better educated customer, will get more out of the experience if you can speak intelligently regarding instant centers, center of gravity, bar angles ect ect.. Well worth $35 bucks.. http://www.ssapubl.com/(X(1)S(us4hhhad0jtkbbuimkeqlvqx))/product.aspx?nbr=S205
You have a binding issue in the rear suspension. Get the car in the air, disconnect the shocks and run the rear suspension completely thru is motion starting at ride height. Look at the track locater or wishbone it should travel freely while raising and lowering of the housing. Remove the coils from the shocks make sure the shock go thru their range of motion also. Check the intersect point of both sides of the four link bars. And yes scaling the car is very important also. No need to cut apart anything until it's deemed unusable.
Had the rear out a month ago. At that point all the heim joints were cleaned and inspected. Didnt find anything tight or binding with the exception of one fwd mount which had its self locking nut way to tight. Coil overs and QA1 adjustable shocks are new(r). This is a pic of the wheelie bar set up. To lower the height of the bar ,pulled the pins and moved them to a higher slot. After the second run , got to looking at it again and noticed the spring and adjuster was completely unthreaded and loose the L side and just a bit lower than you see it now on the R. Thinking that in itself could have caused the issue.
Interesting stuff. Been following along in prev. thread(s). Steve, is this engine significantly different in HP than the PO's? Don't recall but different trans as well? I don't know squat (no pun inteded) about all this but if so, I'd think it's possible (probable?) that a car that launched well prior, & according to the PO it did, would act differently when more power is applied. Good luck in getting it sorted out. I'm sure you will and seems like it'll be wicked quick/fast once you do.
Wow. Expensive. Would be great if someone re-published this. Back in the 80's I was considering having a chassis built & visited Allston (not sure if it was "the" Alston or a dealer). Still have the toolbox from back then w/the decals from that visit (& the Snap-On decal plastered onto a Craftsman Box, lol. I was working in a shop & buying tools, not spending the $ on boxes).
It hooked and then went immediately to the left is not minor wheelie bar setting not being correct. That's the 4 link being completely out of adjustment (it sounds like that's not the case due to the fact Hawley's guy looked at it.) Broken axle, suspension binding, housing not centered correctly, massive tire pressure difference, or shocks. Get that dude up in the air with no wheelie bars, run the suspension thru it's motion, at least you'll get to see it work.
Alston Chassis Works also has a great book out there on setting up various examples of rear suspensions. In detail and explains why and what adjustment does what. Chris himself wrote it.
Prior outing it did break the R axle along with the lug studs on the L. The rear suspension got put back together exactly as it came apart. Recent alignment showed the car is set up straight from that standpoint. My sister was with me for the very first launch several months ago and after seeing the vid I posted on FB she says it did the exact same thing then. Did fill Jimmy in on the cars history and one of the first things he said was less weight on the nose due to the aluminum block, More power / TQ coupled with the short wheel base can and will change how a 4 link car reacts and drives. Same trans as when denny had the car. Rossler built powerglide Would be very cool if I could test this thing at home but it would never hook like it was on a prepped track and its more than an hour drive in either direction to get one
Forgot about it being an aluminum block. That makes sense that it would require changing the setup along with the higher HP/TQ. Idk what giys normally do but seems it'd probably be worth a track day with someone who knows about setting these things up.
Saw your vid on FB. Serious issue going on there. Either something is out of adjustment, binding or even maybe a weld somewhere is cracked.
Nevermind... I see it is a 2 speed. How much air in the slicks? Assuming they're still radials? Good point about the Tomahawk reducing weight up front. That's likely close to 100lbs less than a girdled, stock block.
I'm certain there is a right combo setup in there to get the car doing its thing correctly without having to cut it all out. But a track day with someone who knows how yo adjust your setup would be worth it......cheaper than wrecking or breaking more on the car.
Still has the Pro Bracket radials on it. They were / are @ 14 lbs. I completely agree and Im hoping Jimmy ( Franks mechanic) will be willing to work with me on this. He's local to the track in Gainesville
Had really planned on doing just that but didnt get enough runs in. I had it mounted in the car and did record the 2nd hit. Havent looked at it yet. Just wanted to see what the gages were reading during the run.
Yesterday Stopped by my buddys shop. They run 632 and mountain motors pro stock cars. Showed em some pics of the bars ,then asked how the car would react if it was loose like that. Cory said the car would come up in the front and pitch left. Showed him the vid. Yep just like that! They offered to scale the car for me on Monday then attend a local TnT to help dial it in. I'd been asking for months for a hand in scaling the car as they have all the equipment to do it. So hopefully its on the right track. Pun unintended!
