Bigger torsion bars please

[GRpufnstuf]

Ok. I have searched the forums and found torsion threads but they all peter out or get hijacked.

 

I want bigger torsions on my 620. Sway-A-Way makes HB 2wd and 4x4 bars. I've read that they are different and especially the 4x4 won't work.

 

I crawled under a HB today a d things look "close enough".

 

Can someone tell me why they wouldn't work if I grabbed all the hardware? If I could fit HB adjuster and LCA mount I could run the 26mm sway-a-way kit and that would make me happy.

 

I'm 1000mi from my truck right now or I'd just go measure stuff myself

 

Thanks!

[erichwaslike]

 

 

http://community.ratsun.net/topic/51115-are-the-nismo-hd-torsions-still-available/?hl=torsion

[GRpufnstuf]

LOL, draw a beard on that baby and you nailed my look.

 

I deserve that some, but I did search multiple times.

 

I Also found that 99996-T4010 part # but its listed as 720 parts so I wasn't sure.

 

I'll order a pair this week thanks!

[GRpufnstuf]

Although, I have to think that V6 HB would have heavier bars.

 

If they could be made to fit it would be about 1/5 the price. You know, Ratsun style.

 

So I still would like my original question answered.

 

Can the HB bars be adapted?

 

I'll work it out for myself next time I'm at the wrecking yard.

[datzenmike]

I doubt it. There's length and then possibly different splines. Pull them yourself and compare.

 

I would keep the stock ones and add a small coil over the shock absorbers.

[erichwaslike]

it says on page 3 of that thread that nissan list the 521-d21 2wd as having the same nismo bars, so they would be swapable... idk that the v6 has a beefyier bar but if it says you can swap 521 thru d21 id guess they would fit. check if they have a different part number in stock form between the ka or vg d21(hardbody) if not then theres no use, if so it might be worth goign to the junkyard....

[datzenmike]

The optional HD front torsions used on the 521 are the standard bars for all years of 620. After that the 720 numbers are significantly different so who knows. The D-21 uses two different bars. One for all Z24/KA and VG30 powered 2wd (I assume light duty)and a HD for VG30.

 

If one bar fit's all these that's news to me. Not saying it isn't true. If so I would imagine a VG bar would be slightly HD for use on a 620.

 

D21 torsion bars are ...

 

34.8" (884mm) long and 0.890" (22.6mm)diameter. If this helps. 4X4 are different. Like 13" longer!!!

[Farmer Joe]

just measured a 620 torsion bar..

 

32 3/8in long.

 

edited...

 

that thread above is what i was talking about...

[GRpufnstuf]

I found the dual rate nismo bars on that torsion thread above. $100 more than the 26mm 720 bar. I think the 720 will be fine.

 

I ordered the M-99996-T4010 from nissanparts.cc just now. $182 shipped

 

I will be researching to HB fit when i'm back at my truck. 2" isn't a huge difference if the adjuster will fit in the 620 hole and the splined LCA bracket will bolt onto the early or late model 620s (disc LCA).

 

I've got my leaf springs pretty firm out back to stay off the bump stops. I'd like the same up front but I gotta maintain that 4-5" drop!

 

Thanks for the measurements!

[GRpufnstuf]

I would keep the stock ones and add a small coil over the shock absorbers.

I looked at this possibility. Like the Monroe sensa-trac has a 300# (combined) spring rate. But I'd like my initial spring actuation to be firmer Then maybe I can just run some good pinto shorty shocks and not get into cutting my shock towers and so on.

[datzenmike]

The pinto shocks are just barely shorter. Also pretty light duty. I would think a heavier truck shock would be better even if you do have to raise the mount

[GRpufnstuf]

The pinto shocks are just barely shorter. Also pretty light duty. I would think a heavier truck shock would be better even if you do have to raise the mount

Right, AND when you said heavier it occurred to me that the stronger torsions, Or even stock, might overpower wimpy pinto parts.

 

I'll get my new bars installed and look at the HB parts while I'm at it. Then figure out the shocks with or without the overload springs involved

[GRpufnstuf]

Great info from Dime Dave in the 521 forums.

That post would make a great sticky! (If it isn't)

 

Rate increases for different bars over the stock 20.7mm 521 torsion bar

 

620 to 7/77 - 21.9mm, 126% stiffer

620 from 8/77 - 22.0mm, 128% stiffer

720 2wd 10/81 to 12/82 - 24.0mm, 181% stiffer

720 (all others) - 22.0mm, 128% stiffer

Nissan Comp - 26.0mm, 250% stiffer

OK I've done some research. My 98-99 Nissan Motorsports catalog provides some data on truck torsion bars.

 

All 521/620 torsion bars are listed under the same P/N's

99996-T4010 for their oversize 26m bar

99996-T1450 is their 2 stage bar

 

The same part numbers are listed under the 2wd 720. The 26mm bar is also lists for 4x4 720 up to 12/82.

 

They also provide the stock bar diameters as follows.

 

521 - 20.7mm

620 to 7/77 - 21.9mm

620 from 8/77 - 22.0mm

720 2wd 10/81 to 12/82 - 24.0mm

720 (all others) - 22.0mm

I've already ordered the T4010 TBs and I'm happy to support Nissan offering older parts, but next time I'd just go pull the early 2wd 720 24mm bars. I bet that's close enough for my purposes.

I may still do that if my 26mm bars are too stiff. Look for a 26mm classified post in a month or so if that happens.

 

I also want a set of the T1450 part just because they are really damn cool the way they work.

[Farmer Joe]

from what i gather from this previous post, i could use some 720 torsions to get the front in check on a 620?

 

i could totally do this if thats all it takes..

[GRpufnstuf]

That's how I read it. The link at the top leads to a post that lists the sizes of various years and models of truck torsions.

 

I ordered the 26mm Nissan HD bars, M-99996-T4010 listed for 720 fitment but apparently fits back to 521, before I saw the listing for 720 24mm stock bars.

 

I'd take a tape measure along to the wrecker and check length and then count splines to be safe.

 

Just be sure to keep which side they were mounted on straight. They are made for left and right

[GRpufnstuf]

UPDATE:

 

Russell at Titus Nissan in Olympia, WA aka Nissanparts.cc called and informed me that the M-99996-T4010 bars are no longer available from Nissan.  This didn't shock me because the they are made by Sway-A-Way and their site only lists Nissan bars from 1986 and up.

 

I asked Russell to track down the availability of the Nismo bar M-99996-T1450.  That's the dual stage kit that lists for $280 or so.  It's pretty skinny. like almost stock for my truck, but I could set it up with just a touch of travel (soft) before it hit the adjuster and became firmer.  Might be ideal really. But I suspect that will come back NLA as well.  It's not listed at Sway-A-Way either.

 

I emailed Sway-A-Way as well asking about the possibilty of a one off or a T1450 kit, i found a reference to a SaW part# of 1440 for that.  Hopefully they can wrangle me up something.

 

After this I'll be in search of those 1981-82 (14 month run) bars on 2wd 720s.  

 

If anyone has one at a wrecker near them I'd appreciate any size info you can supply.  

If you wanted to pull and sell them to me we could work that out too!

 

They'd have to be the 24mm diameter and if they aren't stamped "L" and "R" please keep track of which side they came from.  In fact keep track anyway because I don't know which left they mean, in the car or looking at the car from front.  I'm 99% sure it's as you sit, like "left hand drive" but who knows...

 

Oh and decent coil over shocks for a little extra support probably.

[GRpufnstuf]

Ok, so I have a confirmed order for M-99996-T1450 Nismo HD Torsion bars.

 

Russell at NissanParts.cc said Nissan has "A bunch" of them in stock.

 

$275 plus shipping.

 

Not super excited about the price, but I love the way these things work/are engineered and I was feeling skeptical about finding 24 or 26mm bars out in the wild.

 

He said they don't have and don't plan to stock the M-99996-T4010 26mm bars again.  Still no response from Sway-A-Way but that's what I expected after reading about their obsolete customer interface.

 

The bars are shipping to Portland where my truyck is.  I'll be throwing them on and tuning them in along with some other maintenance to get ready to drive the truck back to LA.  This will all be at the end of September (2013)

Pix and write up to follow.

[GRpufnstuf]

Bars arrived and they are beauties.

 

 

They measure 32.5" long so the "should" fit the 620. I'll be finding out tomorrow

 

The instructions are confusing:

 

Note the "front of vehicle" text?

VS

 

Maybe the more aged page is for older vehicles? These were listed as 720 bars but the schematic says 720 to '86 and HB 2wd after that.,

 

So I'll be fitting them with the extra hardware toward the front of the car. It looks to me like it would interfere with the dust boot on the adjusters otherwise.

 

Instructions say that 1/8" at the adjustable stop on the T bars = approx 1" at the wheel. I'm going to take that down by half so most of the travel to the bump stop is as firm as possible.

 

More pix:

[]2eDeYe]

Those receivers look way different than the 620 ones. You will probably have to use the ones that are on the truck. Basically you will use the bars only and nothing else in that kit. Excited to see how well the work for you. :D

 

 

Edit: Here is a shot of the 620 receiver (splined lever arm) to give you an idea of what I am talking about. (thanks Bleach)

 

[GRpufnstuf]

The receivers are an addition rather than a replacement.

 

They are what I am SO excited about!

 

The big tube utilizes the splines in the middle of the bar and locks out almost half the bars twist when it hits its stop.

That should nearly double the spring rate. Perfect. Also they are white

[heretic]

I'm not so sure about that redeye..... I think maybe the "gold thingys" might be a mechanical way of preloading the torsion bar ...  the small gold piece would be anchored on the torsion splines just in front of the OEM reciever where they are "double cut" & the longer gold piece would be anchored on the splines half way down the bar & retained by the circlip, similar to the stock clips on the OEM reciever... if that make sense.

 

EITHER WAY its all very interesting. 

 

...... Basically you will use the bars only and nothing else in that kit. Excited to see how well the work for you. :D

 

 

EDIT: hahahaha not sure how I missed the OP's reply ....  well I guess he answered that

[]2eDeYe]

I get it now, the gold pieces attach at the control arm end and you use the trucks stock lever arm. I was going cross eyed for a minute there trying to visualize it :lol:

[Eagle_Adam]

quietly watching.... 

[heretic]

:) THAT is where it gets confusing for me because of the instructions... it implies both... I personally think, mechanically speaking the gold pieces would go to the rear of the vehicle BUT I tend to over think shit  :w00t:

 

 

I get it now, the gold pieces attach at the control arm end and you use the trucks stock lever arm. I was going cross eyed for a minute there trying to visualize it :lol:

[heretic]

AND.... I'm still wrong .... kinda ... the gold pieces don't preload ... read the caution section........ 

 

 

the bar is basically progressive..... these things are pretty damn cool.