Blocks ?

[bad6772]

Ok guys newbie to the air ride world as most of you know............SO here is the dilemma.......With my (soft spot in the rear) I run roughly 60 pounds..The ride is awesome But I am way to low...And add to the fact that I get a little axle wrap vibration....If I air up to roughly 80 the axle wrap is gone.But my ride is gone and it sets like a 4x4....So I guess my question is.........More than likely taking the 3 inch block out would eliminate all of this? My only reason for the blocks was to make sure I could lay in my C notch as much as possible...I am running slam RE-7s...And I was not sure they would collapse enough to do this.......... Not sure if it matters....But my engine is roughly in the 385 range in H.P and over 400 ft lbs of torque...I also run a 4:13 rear gear with a Mini Spool.......I run a Stock 350 T.C.I street fighter stage 3 and a 3,000 converter?.........all are in stock locations........??? any help would be awesome.......

Edit........I am running stock 72 trailing arms and I have a C.P.P C notch. and I run a C.P.P deluxe trac bar kit.........

[tcb-1]

Tony,
yep, I'm running close to a 3" block in the rear.

when your describing the vibration, is it at a certain speed, rpm, or tire speed? since Sweet Pea is a lwb, you have a two piece driveshaft, correct?

if you do have a 2 piece, I could see the angle of the drive shaft pinion to the carrier bearing being quite steep.

I'm thinking you may need to install a set of angle wedges since the rear end is probably angled 2-4 degrees at ride height. they are cheap and you can pick them up at local drag racing shops or Speedway.com. however, taking the blocks out would lower this angle (at ride height) and reset the natural frequency on the drive shaft/differential pinion shaft.

[bad6772]

Doug its just under hard acceleration...Only time I notice it anyways...Yeah I have a two piece shaft....So if I do take out the blocks...Would I still be as low? when Aired out...Assuming the bags now are not even close to fully collapsed....?

[VA72C10]

You could always do 2" blocks. On my longbed frame with the CPP notch and ECE extreme trac bar, I had 2" blocks and it would rest on the small bump stop in the notch. So you'd still be as low.

The other thing to consider is I flipped my carrier bearing mount. That helps with the driveline angle. It is recommended on a longbed for anything over a 6" drop

[tcb-1]

most bags (air lift, firestone, slam specialities) will collapse down to 3" when compressed. so, with your current setup aired completely out, measure the rear bag height. if it's fully collapsed and they are 6 to higher range, you should be able to lay on the c notch without blocks.

dumb question. did you experience any vibrations before your lower altitude? sometimes vibration at acceleration points to a u-bolt issue. just thinking out loud.....

[bad6772]

No doug I never had any issues before...All U-bolts are new...I switched from Leaf to trailing arms....I torqued my U-Bolts at 175 figured that was more than plenty....Its only on hard accelerations. Driving normal from a light it does not really do it...None that I feel anyways.....But if I mash the gas HARD....it does it pretty noticeable....It feels as if I was trying to brake torque...That little vibration before the tires let loose....But With Sweet Pea...I have never had to brake torque it...It just fries the tires when the gas is mashed...everything is new...When I did this....The only thing that I re-used was the donor rear end....I changed my spool over and had no issues or added pinion shims....I did re use all the brake hardware as well....But got new wheel cylinders and obviously shoes.....

[bad6772]

Originally Posted by VA72C10

You could always do 2" blocks. On my longbed frame with the CPP notch and ECE extreme trac bar, I had 2" blocks and it would rest on the small bump stop in the notch. So you'd still be as low.

The other thing to consider is I flipped my carrier bearing mount. That helps with the driveline angle. It is recommended on a longbed for anything over a 6" drop

I have never heard that VA....??? huh...Do you have any pictures....what is all involved?..........

[bad6772]

TTT any other input?

[VA72C10]

The first I heard of it was ivel designs. If you flip the carrier bearing mount it helps with the drivetrain angle on a lwb that's got a large drop. Right now I assume the driveshaft has to have a pretty decent angle on it when you're laid out.

Here's the link to the post and the picture of my flipped mount from my old build thread.
http://67-72chevytrucks.com/vboard/s...&postcount=135

note where I drilled out the rivets on the bottom...then it was spot welded through the old rivet holes and welded the edges for extra support when flipped...

[bad6772]

Update...So I started looking tonight at my rear suspension....And checking everything out...Turns out my left rear brake shoe was hanging up pretty bad..Seems the springs are totally week...Will get a service kit this weekend...But I adjusted both rear's in to just go for a ride......Vibration is now totally gone unless I dump it in the rear..Even with the minimal 30 psi in the rear...And HARD acceleration......Nothing...she just fries the tires...So by this weekend I should be all good........Thanks for all the help.......

[tcb-1]

wow Tony. I would have never guessed that was the issue! glad you have s.p. running like a champ!

[bad6772]

Yeah me neither.Doug.....Seems to be the big factor at this point....That is why I was asking you so many questions......lol other than the two piece drive shaft I based my set up around yours.....lol.....Well...And Lolife Keith, always braggin on the Slam Bags...I had to go with them....lol.....But yeah....Seems that brake was the major issue....I never ride this thing aired out...So I am uncertain if it does it then..But my pumpkin kisses the bed way before I am aired out completely.I run my rear around 60 to 80 psi...And at either of those pressures I had no wrap...None that I felt....Even at full throttle.....

[lolife99]

Originally Posted by bad6772

Yeah me neither.Doug.....Seems to be the big factor at this point....That is why I was asking you so many questions......lol other than the two piece drive shaft I based my set up around yours.....lol.....Well...And Lolife Keith, always braggin on the Slam Bags...I had to go with them....lol.....But yeah....Seems that brake was the major issue....I never ride this thing aired out...So I am uncertain if it does it then..But my pumpkin kisses the bed way before I am aired out completely.I run my rear around 60 to 80 psi...And at either of those pressures I had no wrap...None that I felt....Even at full throttle.....

I do like my Slam Specialties bags.
I only run 50psi in the rear bags on my blazer.
(80 psi up front)
Does your truck ride rough with 80psi in the rear bags?

[bad6772]

It is not bad....But not nearly as nice as the front ride..I think I may remove the blocks to aide in the ride....Seems the halter my max lift...quite a bit.....

[lolife99]

Originally Posted by bad6772

It is not bad....But not nearly as nice as the front ride..I think I may remove the blocks to aide in the ride....Seems the halter my max lift...quite a bit.....

I'd run a 2" block.
Did you see Leevon's post on lowering blocks and associated parts?
http://67-72chevytrucks.com/vboard/s...d.php?t=405611

[bad6772]

LOL.........Keith I just ordered the two inch blocks.......lol.....Figure I could still lay out ??? thoughts on that........lol.......Edit.......Some say I can with out blocks all together...But I have not had the time to get out and measure anything......