Help I cant get the car to leave

Discussion in 'PSI Superchargers Tech Questions' started by koister, Jan 2, 2013.

  1. koister

    koister New Member

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    1965 Belvedere tube frame, 50/50 weight distribution, 4 link 2400 lb car, 572 ci Blown Alcohol hemi 11.5:1 static compression, 768 lift 292/294 lift 116 cl cam, 1271 hi helix making about 20 lbs of boost.

    I cant get the car to leave. Al it wants to do is wheelie. I have the bars up at 9.75 inches and she still hits them hard enough to unload the tires.. I just added 55 lbs of ballast to the front end and that helped. Raised the wheelie bars up to 10 inches limited the frontend travel to about 1 inch only had about 1 click of compression in the rear shocks and 3 clicks of rebound. 4 link is set at 51.1" ic at 8" off the ground 105% antisquat. I launched the car at 3000 rpm off the brake and then pushed into the pedal and it actually bounced the back tires off the ground ( Goodyear 33x17 the ones with the real stiff sidewall, old prostock tire) at which time they went up in smoke.
    Help.................... were do i go from here????????????????????????????

    Ken
     
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  2. Mike Canter

    Mike Canter Top Dragster
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    Your wheelie bars are way to high and the compression on your rear shocks is not stiff enough and your rebound is too loose. What rear springs and rear shocks do you have? What kind of ignition timing control do you have. What rear tire pressures are you running? What rear gear do you have and what first gear
     
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  3. koister

    koister New Member

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    Response to Mike

    I have strange coil over shocks and springs. The springs are 110 lb/inch. So the compression on the shocks is so stiff that i can hardly push move the car when pushing down on the back end. but ok i will accept what you are saying. As far as rebound you are saying i should stiffen it up as well?

    I have a digital 7 box that i use to take timing out. I have 34 degrees of timing set and then i am taking out 10 degrees at launch and bringing it back in over 1.5 seconds. I am guessing i have too much initial and am not taking out enough correct?.

    I am running 5.75 lbs of air in the tires as the weather was cold, ie 53 degrees. I have a dana 60 in the car and am limited as to the rear gears i can run but i am running a 4.10 gear. Also a point to note is that i am running a glide with a 1.8 first gear but i think i have way to much stall in the convertor. It is 5500. I was thinking of pulling it and get it redone to stall around 4000.

    BTW - thanks for the feedback. any and all is greatly appreciated as i would like to get this thing down the track. My best run to date is an 8.14 with my pedal stop set at the half position. You might ask why i have a pedal stop. it is so i dont do something stupid while i am getting used to the car and also getting the car to straight. I dont do this as a profession just a hobby. thanks again.
     
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  4. Ken Sitko

    Ken Sitko Super Comp

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    I agree, put the wheelie bar down as low as you can, it will bring up the wheel speed and help the car launch properly. Your tire pressure sounds about right, on a modern tire more pressure will hook it harder, less will cause it to spin more.
     
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  5. koister

    koister New Member

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    response to Ken

    Ken,
    When you say as low as i can. Do you mean like an inch or two off the ground??
    Thanks
     
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  6. koister

    koister New Member

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    Clarification on the tire

    I am running goodyear slicks D4a compound which i was told by the midwest goodyear rep is the old prostock compound. In my post above it sounds like i am running old prostock slicks. The tires are new just my poor writing skills.
     
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  7. Mike Canter

    Mike Canter Top Dragster
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    You need 150 lb rear springs. The rebound on the rear shocks controls the initial hit on the tires. If the are too loose you get too much frame to axle separation and a hard hit. The tighter the rebound the less the hit. You want the compression as tight as the track can handle. I would start off about 3/4 tight. Did you actually measure the four link and map it out? It is real close to what I think is right. Bring the wheelie bars down somewhere between 6 and 6.5" to start with. I not a converter expert but your logic sounds correct. How old are those Goodyears. Are the 36" slicks. These are just general recommendation to get you into the ballpark. What's heads are on that motor?
     
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  8. Joad Donnelly

    Joad Donnelly Member

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    Don't be afraid to pull more timing to help calm it down.

    Joad
     
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  9. Randy G.

    Randy G. Top Alcohol

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    Instead of pulling so much out of it at the hit I'd leave the power in it to get the car up on the tires (to try to spin the tires and get wheel speed) instead of bogging the motor and sticking the tires, resulting in it climbing the ring gear. Once it's off the starting line I'd pull some back. Been there done that with 4 link converter cars. Mike is actually recommending changes that do the same thing, but I'm a bigger fan of doing it with the power you paid big $$ for instead of throwing it in the garbage by retarding the timing.
     
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    Last edited: Jan 2, 2013
  10. koister

    koister New Member

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    relpy to Mike

    I will order some heavier rear springs.
    I measured all of the locations of the brackets and holes and then put them into a 4 link program and use the program to map out my 4 link settings. The goodyears only have about 10 runs on them they are 33s as i cant really fit anything larger without major surgery to the car. Thanks again for all of the feedback.
    ken
     
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  11. koister

    koister New Member

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    Reply to Randy G.

    Randy given that i am a neophyte in this game I am probably about to ask a question that will leave you wondering what the hell i am doing with a car like this in the first place. Well i kind of went crazy when i built it and when i got in it the first time i thought oh my god what have i done. I am now starting to get used to all of the power but still i think i went a little overboard. Anyway, when you say spin the tires how much spin are we looking for? I am assuming some spin but not enough that they start smoking for example. Here is a couple of youtube vids of the car not the best but it might give you an idea of what is happening. the first is the burn out and the second is the launch. View the second one in full screen it may make it easier to see.
    http://www.youtube.com/watch?v=uNIzMsOlmww
    http://www.youtube.com/watch?v=Qqc4OdR6VNQ

    Thanks again,
    Ken
     
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  12. koister

    koister New Member

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    Forgot to answer the head question

    I have Stage 5 Millenium heads on the engine.
     
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  13. Mike Canter

    Mike Canter Top Dragster
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    So those are top fuel heads with about 170 cc chambers? How much does this car weigh, 3000 lbs?
     
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  14. koister

    koister New Member

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    reply to mike

    Dont know if they are top fuel heads but they are 170 cc chambers and if i remember correctly 2.45" intake and 1.95 exhaust valves or in that ballpark. The car weighs about 2400 to 2500 with me in it. I just added 55 lbs of ballast so closer to the 2500.
     
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  15. koister

    koister New Member

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    reply to mike 2

    Also i have no idea what kind of power the engine is making as i have not dynoed it. My Machinest thinks it is probably pushing 2000 hp but that is a guess at best. I built the engine. Diamond 11.5:1 pistons, dykes top ring, napier second ring, keith black billet crank shaft 4.5" bore x 4.5 inch stroke BME alumminum rods (something like 7.082 length) .904 lifters LSM Camshaft (60 mm 768 lift 292/294 116 cl) littlefield hihelix 1271 25% od. Clevite V bearing mains and rods, enderle big and ugle hat, 990 pump. Again this is my hobby, first blown alcohol engine and car, and i basically go out and test and tune the car.
     
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  16. Mike Canter

    Mike Canter Top Dragster
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    I understand where you are coming from. It is a great way to learn. Once you can get it down the track the real fun will start.
     
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  17. TR Chassis

    TR Chassis New Member

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    I think you need a different converter setting with a much lower stall. We had similar problems with our FED and JW recommended tighten up the convertor< which they did. We were doing wheelies and shaking the tires before, now it just leaves with maybe just a tiny wheelie. In my opinion you need to get a baseline and I don't think adjustment of shocks etc. is going to make a difference until you get that baseline launch. Just my opinion.

    Rick
     
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  18. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    A pedal stop is a big no-no on a blown & injected motor. You create an extremely lean condition because the barrel valve never opens all the way. Even at half throttle your blower will still probably make 80% or more of it's boost and the fuel flow is way less than that.

    Speaking from experience of learning how to drive an alcohol car, a car that gets on the tire is way easier to drive than a car that is lazy and just shuffles around on the tire. You're best bet is to make full throttle runs and just stay in it as far as you are comfortable.

    My old Jr. Dragster car owner told me when I started licensing in TAFC...there's an invisible string between your right nut and right foot. When that nut sucks up, so should your foot.
     
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  19. AFC357

    AFC357 New Member

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    You have NO IDEA how many Customers I have tried telling the same thing to!!....."Lets just leave the burn-out limiter on for the run".......Doesn't work!! But I have seen many "try"
     
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  20. koister

    koister New Member

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    reply to rick

    Rick,
    I was thinking of taking the converter down to around 4000 stall. what kind of stall did you guys have in your converter. BTW- it is a Jw converter. I think i will give them a call tomorrow.
     
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