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Old 04-10-2008, 06:24 AM   #26
prostreet1967
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Re: pretty dissapointed. (track results)

i dont know they just seem stiff and hard to push down and my uncles truck is soft and he said with that setup he wasn't spinning as bad as i do i know i need to check into some tires but that just don't seem right
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Old 04-13-2008, 07:05 AM   #27
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Re: pretty dissapointed. (track results)

have been thinking the springs were to stiff now i think they might not by stiff enuff. there is no bounce in suspension seems to be to stiff heres my measurements

all measurements with truck on ground

before

shock bolts center to center

L 12 3/8 R 11 1/2

after

12 11

spring loaded

before

L 10 1/4 R 11

after

9 3/4 9 3/8

the right side was obviously preloaded the guy that did it said it would help with traction. i got them as close as i could to equal.

another thing when i let vehicle down it seems to me the shocks are compressed most of the way if not all the way. when i place jack under rearend 1 pump and tires are off the ground (as if the suspension is already compressed.

please feel free to ask for any more measurements that can help address this issue.
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Old 04-14-2008, 08:34 AM   #28
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Re: pretty dissapointed. (track results)

Do you know the front axle weight?
How about the rear axle weight?

Before we can help you identify correct spring rate, we need to know your axle weights.. Do you have a local scale you can go get the above weights? Weigh the truck with you in the driver seat, front tires on the scale, then both front and rear tires on the scale. That will give you front weight, total weight, then subtract front from total to get rear weight.

Do you have factory front springs? If not, how long are they uncompressed and do you know the spring rate?
Can you tell us how much upward travel you have when you jack it up from the crossmember. Need to know when you start lifting taking the weight off the front tires.

Disconnect the front shocks and recheck. Did it make a difference?

It looks like you do not have factory rear springs due to the coil overs. Any idea of the existing rate? They might say on the spring.
Also what is the length of the spring?
How far are the adjusters turned up? (Bottom, 1/3, 1/2, 2/3, 3/4, top)

Do you have a front sway bar?

Lets start there..
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------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49

Last edited by Super73; 04-14-2008 at 08:45 AM.
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Old 04-14-2008, 09:16 PM   #29
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Re: pretty dissapointed. (track results)

no the rear springs are coil overs but the shocks are not adjustable im using the cheap ones that came with the kit. havent upgraded to adustable coilovers yet.

the readings of the rear springs are in post above. but they are 12 inch springs the tag says 170 pounds.

the rear suspension has no movement. when i place jack under rear end one pump gets rear tires off th ground. i put jack stands under frame, removed rear springs reinstalled shocks and raised rear up and checked for binding. they went up and down smoothly.
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Old 04-14-2008, 09:27 PM   #30
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Re: pretty dissapointed. (track results)

heres a pic of rear suspension can get more if needed.

i did lower the right coilover some.
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Old 04-14-2008, 10:36 PM   #31
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Re: pretty dissapointed. (track results)

I'm not wanting to know shock setting for the rear.. I want to know where the coil over adjusters are sitting at your ride height. Are they turned bottom, up 1/4, 1/3, 1/2, 2/3, 3/4 or at the top of the screw on the body of the shock?

Your pic isn't blowing up for me.

Don't worry about no movement on the rear suspension with the jack. All your weight is already settled on the rear axle. Jacking it up from that axle isn't going to change that. Mine starts moving up as soon as I put the jack under it as all vehicle should do that.

Can you messure the length of the rear spring at ride height for me? Try to climb under the truck with out it on a jack. When you rais the back you could be putting more weight on the front axle and taking weight off the rear some.


How about the front info from the previous post.
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------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49
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Old 04-15-2008, 11:25 PM   #32
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Re: pretty dissapointed. (track results)

well i got truck scaled today readings are off a little.

front 2360
rear 1420
total 3760

i put front wheels on for front reading
put rear wheels on for rear reading
whole truck on for total reading.

maybe the lady writting it down meant 3780
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Old 04-16-2008, 12:07 AM   #33
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Re: pretty dissapointed. (track results)

thats with about half a tank i forgot to fill up first
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Old 04-16-2008, 02:30 AM   #34
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Re: pretty dissapointed. (track results)

Truck scales measure in 20lb increments. If it's right on the line 9-11 lbs, it will be hard for it to pick it up. But that gives us a real good start..

Your front end is not much heavier than mine was when I started messing with springs (Mine was 2,260). Here is the info for the spring I am using:

Moroso Sring 47140
240lb rate
17 3/8" long

Link: http://67-72chevytrucks.com/vboard/s...d.php?t=277773

Here is a picture of it after the springs have settled. http://73-ls1.com/63truck/track4-4/profile.jpg


I would guess that this spring would be pretty close to what you need / want. Now, it might sit a little lower than mine (I can take a few more pics if you want).


As far as the rear, let's play with that after you get the front doing what it should do..
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------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49
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Old 04-16-2008, 03:22 AM   #35
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Re: pretty dissapointed. (track results)

thanks alot shaun i really do appreciate all the help and advice. yeah some more pics would be nice. would also like to see the engine bay if u dont mind, i have been wanting a ls engine for my truck for the longest but they are so dam expensive.

so ur front weighed 2260 what does it weigh now?

i agree i will definetly get the springs, how about the shocks ur using any info on those would be nice.

i talked with chassisworks when i got back from scales and the wanted measurements of springs with weight on them and they said it might need a 150 spring but im going to wait and see what happens with the front.
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Old 04-16-2008, 05:23 AM   #36
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Re: pretty dissapointed. (track results)

As I mentioned on the phone, I'm going to be putting a different front shock in my truck. If you want to give these a try with the new springs, pay for the shipping. If they work for you, well, then you can send me a little beer money

My front now weighs 2,050 and rear is 1,800 with a half tank of gas (tank is a 16ga cell in the back of the bed). That's me in the driver seat.

It weighed 2,260 with:
The front bumper on
7" steel wheels and 275/50/15 (Now 6" draglite with a 205/75/15)
Batterey in front
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------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49
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Old 04-16-2008, 06:46 AM   #37
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Re: pretty dissapointed. (track results)

well i have the drag lites, battery in bed, and no front or rear bumpers no tail gate, with a big block. with a half tank as well. i will gladly pay shipping and if they work out send u some beer money. just let me know when u get ur new ones in
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Old 04-16-2008, 06:51 AM   #38
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Re: pretty dissapointed. (track results)

shaun, in my competition engineering catalog with the trick springs they say u may need to modify coil for proper ride height by cutting half coils at a time whats ur take on this should i go with a stiffer spring? i like the ride height of urs did u cut any on urs. proplaply order springs this week sometime only 86 bucks.
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Old 04-16-2008, 07:04 AM   #39
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Re: pretty dissapointed. (track results)

Agreed on the carb,get at least a 850.Just for thought factory 427s had stock 830 cfms.
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Old 04-16-2008, 07:35 AM   #40
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Re: pretty dissapointed. (track results)

Ok, knowing you have done the things I have and are about 300lbs more on the nose, you will most likely want either a longer (which will be very hard to fit) or a slightly heavier spring. I worked my spring backwards and added 300lbs to the figure. Here are the measurements I came up with..

18" long spring a 260lb rate
17" 300lb rate
16" 350lb rate

I think that might be a little on the heavy side. Here are the figures adding 200lbs in:

18" long spring a 250lb rate
17" 280lb rate
16" 330lb rate

The thing to remebder is if you have a really long light spring and it sits too low for your wanted ride height, you can always put a 1-2" spring spacer up top before putting the spring in. As long as you don't induce coil bind under bump, you'll be fine and store more energy than with the shorter stiffer spring.

Quick way to figure out where you will induce coil bind, count the gaps and measure then. Multiply them together (IE 15 gaps, .1 between = 1.5") So that means you have 1.5" of spring copression before bind. You would have about double that number for wheel/tire travel due to the geometry.

So when you call Moroso tell them you are looking for a spring with roughly the above rates/lengths and a coil bind of less than 7.5"

When they give you part numbers ask these questions:

Uncompressed height
Fully compressed height (Bind height)
Rate

Then I'll work the figures again for you with the info they provided.

Order a couple of them, set them in the truck and see what ones are closest to the ride height you are looking for keeping in mind they will settle 3/4 - 1"


I did not cut anything out of mine. Just did the math to find the right spring
__________________
------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49
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Old 04-17-2008, 12:32 AM   #41
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Re: pretty dissapointed. (track results)

im lost is 7.5" how much i need or do i need to measure my old springs to get
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Old 04-17-2008, 07:47 PM   #42
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Re: pretty dissapointed. (track results)

7.5" in my opinion is the max compressed height you can use in the front end. If it is any taller than 7.5" fully compressed you most likely will not get full travel out of the front suspension and induce coil bind.

Example would be my spring:
17 3/8" long uncompressed
aprox 6.5" fully compressed (inducing coil bind)
240lb rate.
__________________
------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49
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Old 04-18-2008, 01:17 AM   #43
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Re: pretty dissapointed. (track results)

Quote:
Originally Posted by prostreet1967 View Post
well i got truck scaled today readings are off a little.

front 2360
rear 1420
total 3760

i put front wheels on for front reading
put rear wheels on for rear reading
whole truck on for total reading.

maybe the lady writting it down meant 3780






The only way to get a good reading is to use a set of 4 wheel racecar scales . I dont know how much my setup moves the weight and I have a heavy Dana 60 rearend and 2 rear mounted batteries . My weight is 3700 w/me in it . 2100 front 1600 rear .
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Old 04-18-2008, 01:31 AM   #44
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Re: pretty dissapointed. (track results)

Quote:
Originally Posted by regan wilson View Post
The only way to get a good reading is to use a set of 4 wheel racecar scales . I dont know how much my setup moves the weight and I have a heavy Dana 60 rearend and 2 rear mounted batteries . My weight is 3700 w/me in it . 2100 front 1600 rear .
are u running rack and pinion, and aftermarket brakes.
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Old 04-19-2008, 10:20 PM   #45
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Re: pretty dissapointed. (track results)

Yes .
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Old 04-19-2008, 11:16 PM   #46
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Re: pretty dissapointed. (track results)

you might need some better fuel if its popping/pinging at high rpm's too --- a compression check should be able to verify this. If it has a lot of squeeze, you may have to mix some 106 or 110 race gas in with some premium pump gas to get it to run right with the ignition advanced
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Old 04-20-2008, 03:40 AM   #47
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Re: pretty dissapointed. (track results)

i was reading some other one elses post and he was having problems about it not pulling in 3rd gear. long story short he had the filter before electric fuel pump which was causing turbulance. so im going to move my filter and see what happens.if i still have problems i will check into that though thanks for the advice
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Old 11-01-2016, 07:40 PM   #48
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Re: pretty dissapointed. (track results)

been awhile truck pretty much sat 10 years.
did a complete ls swap, turbo fab, fuel system n 20 days for a race. was good motivation and fun.
5.3 4l80e s475 circle D converter
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Old 11-02-2016, 02:18 PM   #49
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Re: pretty dissapointed. (track results)

And how did it go?
__________________
------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49
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Old 11-02-2016, 05:49 PM   #50
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Re: pretty dissapointed. (track results)

lost race but didn't have high hopes of winning. was just glad to have made it. was great motivation for sure. Lost first round to a diesel turbo n nitrous.
finished truck hours before race after 36 hours of straight working on it. didn't have time to tune or test. but it was fun.

was unable to log boost so was scared to turn it up any. took out next night and found it was leaving on 1# and running 6 total.
found a few small boost leaks and been fighting issues with waste gate springs finally got it making some boost and the dang map sensor split open. took a week to find that issue.
took out Saturday n made a pass on 10# feels pretty good. looking forward to getting more data and turning it up. may take to track in 2 weeks.
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