"The" Homewrecker
- Thread starter Ishiftem
- Start date
CDNpontiac409guy
Banned
You're right there, Shiftem
. Car 60 ft's great, and in in good air, your MPH COULD possibly put you in a high 10.
Stick cars will MPH a little higher than an auto car, with the same ET. As I mentioned, I've been trying to get mine to 60 ft properly, for a number of years. My 3640 pounds going 123 MPH, is wonderful, but I just can't get below 1.60 60 ft.
Sure wish I could do those suspension mods you have
.
As for your car twisting ?
Can't IMAGINE how that could happen on a rust free, no-miles car
I have an 8 point bar, factory body mounts. Car is straight as a milling table.
I don't think you ever mentioned any specs about your engine ?
Must be making good power to go that fast, with the weight you have
. Car 60 ft's great, and in in good air, your MPH COULD possibly put you in a high 10.Stick cars will MPH a little higher than an auto car, with the same ET. As I mentioned, I've been trying to get mine to 60 ft properly, for a number of years. My 3640 pounds going 123 MPH, is wonderful, but I just can't get below 1.60 60 ft.
Sure wish I could do those suspension mods you have
.As for your car twisting ?
Can't IMAGINE how that could happen on a rust free, no-miles car
I have an 8 point bar, factory body mounts. Car is straight as a milling table.
I don't think you ever mentioned any specs about your engine ?
Must be making good power to go that fast, with the weight you have
You're right there, Shiftem
Stick cars will MPH a little higher than an auto car, with the same ET. As I mentioned, I've been trying to get mine to 60 ft properly, for a number of years. My 3640 pounds going 123 MPH, is wonderful, but I just can't get below 1.60 60 ft.
Sure wish I could do those suspension mods you have
As for your car twisting ?
Can't IMAGINE how that could happen on a rust free, no-miles car
I have an 8 point bar, factory body mounts. Car is straight as a milling table.
I don't think you ever mentioned any specs about your engine ?
Must be making good power to go that fast, with the weight you have
We have tried alot of different suspension settings. We had a 46" long instant center 8.5 inches off the ground. That gave us 86% anti-squat with our 28" cg height. It would 60 in the 1.58 to 1.61 range leaving @ 5800. When we got our fuel system straight and knocked 2 tenths off, we had to lower the leave to 5k to get the same 60. Still turning tires 20 feet out. Changed bars for a 42" long and I believe(can't remember now exactly) 13.5" height wich gave us anti-squat of 120%. First run leaving at 5k it flat dead hooked and dragged the motor way down. Raised leave to 5900 and and that's when we started getting 1.540 60 times. Still could be refined a little more. 9" hoosier d07 compound tire with tubes set at 15 pounds hot with double adjustable shocks in back, 175# springs. Front has calvert 90/10 with urethane bushings fit so there is no friction. Clutch is a McLeod sof lok set now at 970 pounds with 11.5 grams of counter weight on each lever. There is more there and I'm sure once the car is straight again, it will 60 better. Still turns the tires about 10 feet out.
I think the car twisted because it is still not stiff enough to reduce flex, but stiff enough to stay flexed.
The motor is really basic. 474" with Ross 10.5:1 pistons, but has the notch (truck block) and thickest head gasket to get piston to valve. Heads are 690 with 2.25 intake valves. Port matched (poorly) to stock intake gasket. Thats it. 100% stock 881 intake with zero port work. 500 cfm carbs with 1" spacer and 1 7/8 headers. Cam is solid roller with .660 lift with the 1.7 rockers and .258 duration at .050. Thats it! Nothing fancy.
The goal is 10.70 to 10.80. That would make me happy. Obviously another 75 horsepower will fix that. What have you done to get yours hooked? I know there is a lot of chassis work done and it looks beautiful.
CDNpontiac409guy
Banned
aaaah, the engine is BIG !
Nice combination of stuff inside. I think upping compression to around an actual 11.5
would greatly increase mid range and high RPM torque. Perhaps a pair of 600 carbs ?
I think the Edelbrock intake would be a pretty simple bolt on of 20 HP as well.
What RPM do you shift at... and go through traps ?
Stock / Super Stock guys run on the ragged edge... generally crossing the traps a few hundred RPM higher than shift point.
What I'm getting at, is maybe a touch more gear in the rear ? Could improve 60 ft, and give slightly stronger torque multiplication all the way.
Your description of adjusting instant centers, etc, is a little over my head
Nice combination of stuff inside. I think upping compression to around an actual 11.5
would greatly increase mid range and high RPM torque. Perhaps a pair of 600 carbs ?
I think the Edelbrock intake would be a pretty simple bolt on of 20 HP as well.
What RPM do you shift at... and go through traps ?
Stock / Super Stock guys run on the ragged edge... generally crossing the traps a few hundred RPM higher than shift point.
What I'm getting at, is maybe a touch more gear in the rear ? Could improve 60 ft, and give slightly stronger torque multiplication all the way.
Your description of adjusting instant centers, etc, is a little over my head
de31168
Well Known Member
Thanks, we're still working on getting it to hook up. Actually we've had a problem even getting a damn burnout with the thing. Finally realized it was hitting the rev limiter and forcing it to drive out of the water even spinning the tires. The very last pass we made (which I drove) made a nice burnout. I am not too familiar with the car yet so I launched at maybe 2,500 RPM at best just giving it a try and it went! We have been messing around with instant centers and pinion angle alot too to see what it will do. I'm not sure the exact lengths and measurements though. It initially started out right behind the front seat, but now it's out to about the pedals at the firewall. I think it was initially hitting TOO hard and shocking the rear end unloading the tires and causing alot of wheel hop. We're going to give it another go on sunday. Check the timing, put a new set of plugs in it, get the tires good and hot and let her rip.
I noticed you said you run 15psi hot on the tires.. is that where you start them at? I know when I talked to Hooiser (we have the same tire) he said start at 14 to get in the ballpark, and dropping the pressure a quarter or half pound will actually put a little more bite in it.
We are going straight for 13:1. Why mess around? haha. I thought about the Edelbrock but honestly I don't like their attitudes and refuse to by one. Last runs I set the light at 6000 and it goes through about 6400. It has a 4.56 and 3.08 first. I think spinning it higher would be a waste given the cubic inches and flow limitations of the heads and intake. Plus keeping the rpm down saves the motor. Really like the idea of keeping maintenance down even if it costs a little power.aaaah, the engine is BIG !
Nice combination of stuff inside. I think upping compression to around an actual 11.5
would greatly increase mid range and high RPM torque. Perhaps a pair of 600 carbs ?
I think the Edelbrock intake would be a pretty simple bolt on of 20 HP as well.
What RPM do you shift at... and go through traps ?
Stock / Super Stock guys run on the ragged edge... generally crossing the traps a few hundred RPM higher than shift point.
What I'm getting at, is maybe a touch more gear in the rear ? Could improve 60 ft, and give slightly stronger torque multiplication all the way.
Your description of adjusting instant centers, etc, is a little over my head
We had a pair of 600s but it runs better with the 500s. If you want I can give you my number and talk at length about the suspension. Too much typing for me.
Leaving at only 2500 with that ET you are leaving a ton on the table. Forget the pinion angle. What you are doing by changing pinion angle is actually changing the instant center. It is more of a fine adjustment and ideally you want the bars set so you run as little angle as possible for the most efficient transfer of power. With a four link you don't want anymore than 1 or 2 degrees. Most of the time wheel hop can be taken care of with shock adjustments. We hit the tires pretty damn hard as evidenced by some of the pics I posted. With the instant center at the pedals, it might be a little too long and low, but I'm having a hard time visualizing it. What happens if you leave at 5k +? What kind of clutch and what is the pressure? If the clutch is too tight, no amount of suspension changes are going to get it to hook. As for burnout, I do a second gear burnout and dump it at about 5500. Let em cook for about a 7 count and drive it out giving it more and more throttle to keep the rpm then roll out of the throttle and push the clutch at the same time. We set the tires at 13.5 cold and checking them immediately after a run they are at 15 give or take a 1/4 pound. Then we adjust them up or down so they are at 15.
CDNpontiac409guy
Banned
Sounds just right, shiftem
I run pretty much the same size tire ( M/T 29.5 X 9 "stick compound" ), and you're right... a little more air is better.
Has to be in relation to car weight. I'm at about 13.5-14 after a run.
Again, mine's a Stocker. No adjustable 4-links. I have the single adjustable QA1's, which I now know are not adequate.
My clutch is the same as yours, using an 11 pound flywheel. With 5.13's, I have lots of rear gear, but something else I learned... my 2.83 1st gear is not enough. That 3.08 that you have, would be just right.
That's intersting about the carbs
I run pretty much the same size tire ( M/T 29.5 X 9 "stick compound" ), and you're right... a little more air is better.
Has to be in relation to car weight. I'm at about 13.5-14 after a run.
Again, mine's a Stocker. No adjustable 4-links. I have the single adjustable QA1's, which I now know are not adequate.
My clutch is the same as yours, using an 11 pound flywheel. With 5.13's, I have lots of rear gear, but something else I learned... my 2.83 1st gear is not enough. That 3.08 that you have, would be just right.
That's intersting about the carbs
Sounds just right, shiftem
I run pretty much the same size tire ( M/T 29.5 X 9 "stick compound" ), and you're right... a little more air is better.
Has to be in relation to car weight. I'm at about 13.5-14 after a run.
Again, mine's a Stocker. No adjustable 4-links. I have the single adjustable QA1's, which I now know are not adequate.
My clutch is the same as yours, using an 11 pound flywheel. With 5.13's, I have lots of rear gear, but something else I learned... my 2.83 1st gear is not enough. That 3.08 that you have, would be just right.
That's intersting about the carbs
Wow i had that same tire and could not get my car to hook worth $hit
my last straw was 11.41 ET 120.48mph with 1.737 60ft:eek and that's why i went with the bigger goodyear 29.5x10.5 i will know more this weekend i hope
Aubrey, those M/T are great tires. Wanted those but the extra .5 diameter would of been too close for comfort on our car. The 29 just ticks the quarter when the tire grows. I think the Hoosier has too soft a sidewall unlike the stiff sidewall of the M/T. Are you allowed to relocate the stock arms or are you stuck with factory mount locations? How do have your soft lok set and have you had wear problems or warping problems? Saw the car over at UMTR and it is very cool. 10s in stock class configuration is WAY cool
BSL409 there has to be a problem with the way that car is setup in either the I/C location or clutch. That 60 foot time makes me sad
. You should be well into the 11 teens all day long and probably quicker. I am going to look over the pictures you sent. Good luck and let us know how the weekend goes with details.
BSL409 there has to be a problem with the way that car is setup in either the I/C location or clutch. That 60 foot time makes me sad
. You should be well into the 11 teens all day long and probably quicker. I am going to look over the pictures you sent. Good luck and let us know how the weekend goes with details.
CDNpontiac409guy
Banned
Thanks Dan
, Yes, I had to re-contour about 1/2" of the rear wheel well lip at the front lower edge.
Nope, lower arms must remain factory stock. I DID re-do the lower bracket at the frame, utilizing the 63/64 "2-position" mount ( station wagons will use the lower ones... as I did, which does get the lower arm closer to horizontal ).
No warping of my clutch components. I do inadvertantly seem to run my a little soft sometimes. Seems to be a VERY fine line between relentless slipping, and hammering the driveline. With the stupid clutch slipping, here is the only in car video ever done during a 1/4 mile pass. This was Medicine Hat, summer 2010, NHRA Stock / Super Stock combo race. 2300 ft altitude, a barometer reading putting the air near 5000 ft, a head wind, and unbelievable humidity... 11.40 @ 119.49 MPH.
, Yes, I had to re-contour about 1/2" of the rear wheel well lip at the front lower edge.Nope, lower arms must remain factory stock. I DID re-do the lower bracket at the frame, utilizing the 63/64 "2-position" mount ( station wagons will use the lower ones... as I did, which does get the lower arm closer to horizontal ).
No warping of my clutch components. I do inadvertantly seem to run my a little soft sometimes. Seems to be a VERY fine line between relentless slipping, and hammering the driveline. With the stupid clutch slipping, here is the only in car video ever done during a 1/4 mile pass. This was Medicine Hat, summer 2010, NHRA Stock / Super Stock combo race. 2300 ft altitude, a barometer reading putting the air near 5000 ft, a head wind, and unbelievable humidity
... 11.40 @ 119.49 MPH.
de31168
Well Known Member
So when addressing the wheel hop issue... which way do you go with the rear shocks? I think we have the same setup on the rear with the dual adjustable coil overs and eibach 175lbs springs. I take video on the starting line and it seems the car will plant and carry the front tire, then it levels back out, then picks the front tire up again, then levels out, then picks it up and carries it until the 1-2. The 3 little "hops" happen all before the car even passes the christmas tree. I watch the stuff frame by frame. The tires have a nice wrinkle to them and appear to bite. I'm wondering if the shocks are still too soft allowing it to compress fully and rebound with the weight still trying to be transferred? I believe the lower "click" setting is just above the middle, 6 clicks, and the upper "sweep" setting is at 4. I'm guessing that's where all the 60ft time loss is at but I'm new to this stuff. I would think you want it to squat in the back and lift in the front and just carry itself out of the beams in a fluid motion before settling back in. Also I'd have to check with my dad but I believe it has a heavy duty RAM clutch in it. We initially had a centerforce in it and the clutch would actually stick to the floor and not return for a few seconds between shifts. This new clutch you really have some force on the pedal, enough to flex the firewall when you push on it. Thanks for all the replies and help with this stuff. It's a learning process and it's great to hear from someone with a similar setup.
That sucks about the not being able to change mount locations. I know what you mean about the clutch. At 8 turns and the 11.5 grams on each lever, the shifts were HARD. We are at 6.5 turns now but am afraid to go lower and cook it. I am really anxious to pull it and measure the wear. If it wore more than .015 with the amount of turns in it we have and limited amount of runs I am going to be really ticked offThanks Dan
Nope, lower arms must remain factory stock. I DID re-do the lower bracket at the frame, utilizing the 63/64 "2-position" mount ( station wagons will use the lower ones... as I did, which does get the lower arm closer to horizontal ).
No warping of my clutch components. I do inadvertantly seem to run my a little soft sometimes. Seems to be a VERY fine line between relentless slipping, and hammering the driveline. With the stupid clutch slipping, here is the only in car video ever done during a 1/4 mile pass. This was Medicine Hat, summer 2010, NHRA Stock / Super Stock combo race. 2300 ft altitude, a barometer reading putting the air near 5000 ft, a head wind, and unbelievable humidity
Sounds like it is unloading the tire more than wheel hop. Do you still have those wheelie bars on and how high are they adjusted? The shocks kind of depend on the I/C location. If the I/C is below the neutral line, it will want to pick the rear end up into the car. Some may view a car set up this way as the body coming down on launch but actually it is the rear end coming up into the car. Above the neutral line and the rear end will separate from the body pushing the rear into the ground. If wheel hop is the problem, increasing the extension will soften the hit. Increasing bump will help keep the rear from bouncing back up into the car. Sometimes wheel hop is caused by irregularities in the track surface and in that case softening the bump will allow it to follow better. As for the clutch that sounds way too stiff. Ours is effortless. Does yours have a sintered iron disc and is the pressure plate adjustable? If so, what is it adjusted to now? Also where will you be running the car Sunday? Maybe I can come out.
I like this thread!
All you guys are just like me, we all just want to go a little bit quicker.
Aubrey, I was looking at this video of your car launching.
http://www.youtube.com/user/Cstock6409#p/u/14/FXjDb4fxxCY
To my untrained eye the suspension looks to be set pretty well.
It does look like the clutch was set to slip a bit too much on this run. I guess it's hard to hit that sweet spot.
Brian, That 1.737 60' time could be quite a bit better. Just to put it into perspective Jim's big fat 62 convertible ran a couple of 1.72's (with 9" slicks)
With a little work you should be able to knock a couple of tenths off that 60' time and that would translate to a 3 tenths at the end of the 1/4 mile.
All you guys are just like me, we all just want to go a little bit quicker.
Aubrey, I was looking at this video of your car launching.
http://www.youtube.com/user/Cstock6409#p/u/14/FXjDb4fxxCY
To my untrained eye the suspension looks to be set pretty well.
It does look like the clutch was set to slip a bit too much on this run. I guess it's hard to hit that sweet spot.
Brian, That 1.737 60' time could be quite a bit better. Just to put it into perspective Jim's big fat 62 convertible ran a couple of 1.72's (with 9" slicks)
With a little work you should be able to knock a couple of tenths off that 60' time and that would translate to a 3 tenths at the end of the 1/4 mile.
Brian, That 1.737 60' time could be quite a bit better. Just to put it into perspective Jim's big fat 62 convertible ran a couple of 1.72's (with 9" slicks)
With a little work you should be able to knock a couple of tenths off that 60' time and that would translate to a 3 tenths at the end of the 1/4 mile.[/quote]
Well I think Thompson is not looking that good for tomorrow they are still going to try and run and I do not feel like driving 4HR for nothing. I will run Sunday at are local track and try for some low 1.50 60ft
With a little work you should be able to knock a couple of tenths off that 60' time and that would translate to a 3 tenths at the end of the 1/4 mile.
[/quote]Well I think Thompson is not looking that good for tomorrow they are still going to try and run and I do not feel like driving 4HR for nothing. I will run Sunday at are local track and try for some low 1.50 60ft
I like this thread!
All you guys are just like me, we all just want to go a little bit quicker.
Aubrey, I was looking at this video of your car launching.
http://www.youtube.com/user/Cstock6409#p/u/14/FXjDb4fxxCY
To my untrained eye the suspension looks to be set pretty well.
It does look like the clutch was set to slip a bit too much on this run. I guess it's hard to hit that sweet spot.
Brian, That 1.737 60' time could be quite a bit better. Just to put it into perspective Jim's big fat 62 convertible ran a couple of 1.72's (with 9" slicks)
With a little work you should be able to knock a couple of tenths off that 60' time and that would translate to a 3 tenths at the end of the 1/4 mile.
If we couldn't go a little faster, what would be the point?
BrianIf you don't get a 1.50, it won't be for a lack of power or rubber!:eek