Opinion on Rear Percentage - Whats to much

[racefastnow]

We run a steel block, aluminum engine with about 56.5% rear percentage. I am wondering if this isnt to much. What would be some issues with to high of a rear number. Car gets in corner excellent, but just has no traction exiting. Had car for a few years now, nothing seems to help. Tried all sorts of lift bar changes, moving it on frame, on rear end, springs, moved every bar on it, changed bite from 20lbs to 200lbs. Car only works on black ice, if the track gets ripped up, the car wont pass a single car, but comes on like crazy if its black ice. always enters corner good, Tried slowing everything down, longer rods. It just doesnt dig and leave a rooster tail when its on the gas, seems to just flop over and have nothing. I can watch the better cars the rear wheel really digs and lifts the car up onto the rf, We have soft springs in front. Nothing seems to help.

[Matt49]

Rear percentage makes corner entry very comfortable because the car is mostly stable. My guess is that the driver is having to man-handle the car at mid corner to get it to turn and that is why you don't have any forward bite to get off the corner.
That's a guess based on what little we know about your setup. Scale numbers, ballast location, springs, bar locations, and shock information would be helpful.

[swingarm4life]

Agree with Matt. Another thing to look at is the chassis brand. Some chassis like more rear than others. Swing arm cars tend to like more rear. Even though that is pretty steep for rear percentage, you can get away with it and have a decent handling car depending on alot of other things (rear springs, shock valving, front springs, 5th coil rate and location, bar angles, etc.) Its kind of a different strokes for different folks deal, you'll see cars now with anywhere from 51.5-56.5 rear.

[racefastnow]

We have literally tried a 1000 combinations. It just doesnt dig. If the track is ripped up and packed down right before our race where the lap times are fast, our car will be a second off the pace. Than when it gets black ice where all the other cars slow down a second, our car will have the same lap time as it did in the mudd. Nothing seems to effect it. We have moved the motor, roll center in the front, softer and harder springs, more roll steer or less, 5th springs changed, moved location from 40 to 32 to back, bar angles, jbar angle. Its become very dissapointing as we always we believe its a matter of setup and can be changed without buying a new or different car.

[Matt49]

Then it sounds like you're down on power. When the track is fast, a 1990 Rayburn should have enough traction to be good even against today's cars.

[racefastnow]

The engine is good, its brand new and has been on a chassis dyno. the car just spins. Cant be in the throttle. and we tried bar angles and rear steer. one way makes it worse, and one small adjustment makes it go straight to the wall. Not sure if the traction is to instant where its loosing right away, or if it doesnt ever load the left rear correctly, this is why we tried a a different lift bar, we made it so it mounted on left on rear end and moved it 4 inches to the left on the frame. It felt like it dug better, but it wasnt any faster, Still had same problem. the left wheel doesnt dig and lift car. Acts like it just rolls over doing nothing.

[racefastnow]

Thats whats bothering us, when the track is fast and tack, it just spins, but when its black ice and most cars have a loose condition, were stuck to the ground and gone.

[phenom08]

Need to list what kind of car, springs, percentages, maybe something simple is off

[MasterSbilt_Racer]

Post video of your car. I almost promise you the driver is busting the car loose to get around the corner with traction in the track.

[Punisher88]

It isn't an old grt with the lr hitting the underslung bar is it? The older cars that bar needs to be dropped.

[swingarm4life]

Drive shaft isnt too long is it?

[racefastnow]

09 Warrior, drive shaft is right. we have it on a chain and nothing is binding or hitting. Its been doing this for 5 years. 200lr 225Rr. Bars are in standard holes from warrior setup. but we have moved them. Right now we lengthened the lr bars an inch moving the holes to keep the rear end square, has 56.5% Rear, have heard an open car run 54.5. this is a steel block aluminum head. The front end seems to work nice now. we changed the roll center a little and shocks and chained it up for travel. gets on rf nice on a bump. We have tried stiffer RF spring no bump, doesnt help with drive at all. Whats always bothered me is i really like the cars on caution when they rock them back and forth they get on the bars easy and the rear end rolls up easy. this doesnt seem to do that. Jbar 9inches and 20 or 22 in lenght i believe. 325 fifth coil at 38 to 34 usually

[racefastnow]

54.5 Left side%. with 140lb bite, we have had it with 20lbs to 200lbs. doesn help. went back to the standard lift bar with it moved 4 inches left on frame from standard

[Matt49]

What we do know now is that you've altered the front end geometry, you've changed 4-bar lengths in the rear-end, and you've moved the lift bar to a non-standard location (not even sure how you pulled that off without hitting the drive shaft).
Based on this and the previous posts, I think you have changed so many things on this car that you are simply out to lunch. Unless you have analyzed the camber curves and roll center migration with good software, you shouldn't be modifying the front end geometry on these cars. Put everything back the way it is supposed to be and put 54% rear in it and it will probably be fine. Put the lift bar back where it goes and 4-bars back at standard lengths.
My guess is that you had a baseline setup 5 years ago except the 56% rear which was making the car too tight on entry (which will make it loose on exit). Since then, you've changed everything except the most fundamental thing that would have fixed it.
I would start over completely with a totally baseline setup and go from there.

[Punisher88]

Is the rf lower pulled way ahead of the left front. If so I would put them even or left front ahead. I had my rf ahead and chased my rearend up the track for two years and put the lf ahead and now it steers better and leaves the corner amazing.

[save the racers]

I'm with mastersbilt racer on this one.

[racefastnow]

9 inch height in jbar from frame to pinion. We have had 100% standard setup even lately, we have gone back n forth. there isnt any warrior cars around here and the ones that were struggled. this one has alot of wins actully, but its garbage unless car is on black ice. never seems to change. we have a 425rf down to a 275, from max rebound at different speeds, to none. we made the lift bar and yes it had tight clearance, wrapped around the drive shaft, the car has track lap record a few weeks ago, but tried same setup again at another track and it was embarrasing. lol We were thinking of using of softer front springs with heavy rebound and having high rear percentage. that was the original idea, but have tried less rebound also with stiffer rf, but did still have 56.5 rear. that part isnt easy to change. i have had rear end straight up, rr ahead, and lr ahead. the roll center changes seem to really have made the front end better, like the attitude now and behavior of it. anyone ran a lift bar with out the heims on the rear end, our custom one was like this and i think there is some counter forces being applied when its moving????. never got around to setting it up with heims, anyways we have since taken it off. not to much longer, its time for a new car im afraid, wearing on the brain. hahaha

[3wheelinphotos]

Race Fast Now not sure who you are but have you called us to go over your issues? Please call us before jumping ship our 09 cars are very fast car with traction an side bite. Our STD setup if a great starting place but gotta stay in touch with us to help you fine tune your car to where you race. Give us a call Mike @ Warrior Race Cars/1G Shock Service 865.573.2411

[A ron]

Wish I had bought a warrior based on 3wheelin's post.

[HuckleberryB4]

You definitely wouldn't/don't see anyone from Mastersbilt offering a hand like that!
Brad was the exception when he was there.

[racefastnow]

Mike, what would it take to have you come out for a weekend and help! lol

[RSS]

If he does that, I will possibly be looking for a warrior!!

[3wheelinphotos]

Race Fast now give me a call at the shop please an lets see what we can do for ya, and far as coming out I travel to a lot of places every weekend to help customers it can happen we are very hands on and doing what it takes to get the customers fast where they are racing not just a general setup and leave ya out to dry. Look forward to hearing from ya. Thanks Mike

[7uptruckracer]

If his chassis win he sells chassis so most builders should be this hands on! Good to see!

[3wheelinphotos]

7up we strive to keep everyone happy with they race car as we can because just like you said if he's happy an winning he's staying in our car and others will see it too. Don't like todo tech stuff over the computer would rather speak with the guy on the phone go over his whole program an how they do things all thru out the night. One single thing is not always gonna fix an issue. Thanks for everyones good comments, everyone get the same support from us regardless of who you are big name or just a weekly guy on shoe string budget. Mike @ Warrior Race Cars

[3wheelinphotos]

Anywhere from 2009 and up....we have made small adjustments thru out every year but for the most part every part on those cars is the same as now and the adjustments are the same. Dirt Track Supply is a dealer for us in SD but we can work with you factory direct with you no issue you don't have to use the dealer if you choose not to.

Mike

[manwplan]

Some chassis builders aren't helpful but there are plenty that are. Lets not misconstrue that because they don't come on 4m they won't help you. Although its been very civil around here lately, maybe others might?

[25drtrkr]

I've always said, Sanford and his guys at Warrior have always been a class act. Sanford helped us anytime we asked, even though we were on another chassis. That kinda help eventually swayed us to start using Warrior chassis.

[rakracing]

I run a updated 2010 warrior now and then for another owner, love the feel of that car the madder you get at it the better it works, if I was looking to buy a newer car for myself that's what id get, had warriors years ago up to 2005 always liked the 02-04 overrail cars, back when Scott Pound was with them and he helped me win a lot of races and a championship.