Jump to content
boushkaa

New member, and new owner of a 521 Project

Recommended Posts

Hey everyone, glad to have found the forum and have found lots of useful information so far.

 

Currently in the middle of an SR20 swap into my 521 that I picked up a few weeks ago. I did have a few questions regarding the frame as I want to modify part of it. I have found it to be a huge pain to deal with the frame crossmember that the trans mount bolts to. I know on other of my cars I am able to detach this crossmember making it much easier to pull the transmission. Has anyone modified their crossmember to make it removable? My initial plan was to measure and make brackets that I would weld onto the crossmember and have it bolt back to the frame using these brackets. Would this harm the cars handling or integrity? Seeing as I am swapping in the SR20 I think I need as much frame strength as I can get. I am new to the 521 platform so forgive me if any of my questions are stupid

 

Heres a quick pic from when I bought it for anyone interested

sexwBSN.jpg

  • Like 3

Share this post


Link to post

Very commonly suggested to make that cross member removable.  You should be fine.

  • Like 2

Share this post


Link to post

Cool truck.same color as mine.

as for handling Its a king pin set up. I would just have left it along and drive it as a L motor as its A COOL TRUCK.

SRs in 510s is a better and EZer set upto do. as the 521 has what you mentioned x memeber  plus a Carrier bearingto deal with when installng a new 5 speed set up.

510 thereare already made X members ect....

I say just leave it.its a cool truck

  • Like 1

Share this post


Link to post
1 hour ago, banzai510(hainz) said:

Cool truck.same color as mine.

as for handling Its a king pin set up. I would just have left it along and drive it as a L motor as its A COOL TRUCK.

SRs in 510s is a better and EZer set upto do. as the 521 has what you mentioned x memeber  plus a Carrier bearingto deal with when installng a new 5 speed set up.

510 thereare already made X members ect....

I say just leave it.its a cool truck

 

I actually got the truck as a roller so this seemed like the best way to move forward. Either way the SR and trans is already in the truck, just I now have to pull the trans one more time to fix an issue with the throwout bearing. So instead of having to pull the motor for a third time I plan to just make the crossmember removable and drop the trans like any other car

 

2 hours ago, thisismatt said:

Very commonly suggested to make that cross member removable.  You should be fine.

 

Ok great, was hoping to hear that it has been done before. Do you happen to know of any threads or links to how they modified it? Just worried my bracket idea may not be the strongest option

  • Like 1

Share this post


Link to post

I don't have any links off hand, but I've seen it done where the xmember is cut leaving a little at both ends extending off the frame, then flat plate welded to all the ends and sinched together with 4 bolts per side.

  • Like 1

Share this post


Link to post

In my opinion that is not just a simple 2 bolts on each side conversion, that is one of the beefiest cross members on that frame and the only thing connected to it is the transmission mount, the torsion bars only go thru that cross member while later versions have the torsion bars connected to that cross member as I suspect it was over built and strong enough to take the extra work load.

There is another cross member in back of that one that is not built like that one at all and I would not trust that one to take up the slack.

Too me between that cross member and the front one under the radiator which is also beefy make a strong base for several things which include the complete front suspension, to me if it is a trailer queen no problem, if it is going down a drag strip or drove like it is I just don't know, but Nissan over built these frames/chassis, it may be just fine.

  • Like 1

Share this post


Link to post

I think I have found a solution that will work. I luckily live about 10 minutes away from a Summit Racing store/warehouse so I was able to go in and look at a few options. I ended up finding this universal crossmember that should work for exactly what I want and be supportive of the rest of the frame.

 

https://www.summitracing.com/tx/parts/awr-xfun10001s/overview/make/tesla/model/x

 

It seems to fit well seeing as it is adjustable and seems fairly strong. The current plan is to cut the old one out and then replace it with this one and have it bolted to the frame rails using the supplied brackets. Here is just a rough mockup with them next to each other.

 

rB895h5.jpg

  • Like 2

Share this post


Link to post

That should work nicely... 

I would personally weld and gusset those brackets in place.... 

Just an idea.....

  • Like 1

Share this post


Link to post

So you do not have torsion bars anymore, what front suspension you going to use?

  • Like 1

Share this post


Link to post
12 minutes ago, wayno said:

So you do not have torsion bars anymore, what front suspension you going to use?

 

 

I don't have the full mod list on hand but it has been converted to coilovers in the front. I bought the truck with the conversion already done. The only thing the truck was missing was the motor and trans which is why I decided to swap in the SR20.

 

zPYZOh9.jpg

  • Like 1

Share this post


Link to post

Ive seen a truck on a trailer, at a show, with coilovers upfront to eliminate the torsion bars.

Ive been gone awhile, and have never seen the truck again.

 

However, I always believed it was a real option.

I think you can make this work.

 

what are you doing for  seats? and how far back is the shifter for for your manual trans compared to the stock?

 

'Anything you want to make removable just needs to be redone to be as strong or stonger. So keep that in mind.

A lot of people can use an angle grinder..

  • Like 1

Share this post


Link to post
2 hours ago, AtomChurch said:

Ive seen a truck on a trailer, at a show, with coilovers upfront to eliminate the torsion bars.

Ive been gone awhile, and have never seen the truck again.

 

However, I always believed it was a real option.

I think you can make this work.

 

what are you doing for  seats? and how far back is the shifter for for your manual trans compared to the stock?

 

'Anything you want to make removable just needs to be redone to be as strong or stonger. So keep that in mind.

A lot of people can use an angle grinder..

 

Well the previous owner seems to have set things up properly. I am unfamiliar with how these trucks came stock, but everything seems to work. Hope to get a proper road test sometime next week after I get the car running and tuned.

 

The previous owner had also replaced the bench seat with some old recaro seats, but I have since removed them and replaced them with a set of Corbeau seats I had laying around the shop for another project. The shifter actually sits pretty close to the stock location. I did have to cut the trans tunnel a bit but I have already found a trans tunnel patch panel so I will be welding that in soon. Interior will be dealt with once I get all the mechanical stuff finished up. 

 

I wish all it took was the angle grinder, I had to break out the plasma cutter to deal with the crossmember. Just got it cut out but am calling it a night. Will be grinding the leftover welds and little parts I missed tomorrow and then getting the new crossmember secured. Will update with a few pictures once I get the new one in.

  • Like 2

Share this post


Link to post

Quick update

 

Finally got everything squared away and the new removable crossmember is installed. Seems to be pretty strong and fits nicely. I did have to make a spacer to get extra height from the crossmember to the actual mount on the trans but It came out exactly like I wanted. Already pulled the trans this evening and am fixing a few clutch issues I encountered. Thanks everyone for their input. I might have to start a build thread eventually.

 

lwAiKr5.jpg

  • Like 1

Share this post


Link to post

Like to see where this build goes. Looking good so far and like the direction your going. Keep it up. Is there a big import/slash mini truck thing in Texas.

  • Like 1

Share this post


Link to post
2 hours ago, mrbigtanker said:

Like to see where this build goes. Looking good so far and like the direction your going. Keep it up. Is there a big import/slash mini truck thing in Texas.

 

In Texas? Probably more mall crawlers than anything else.

  • Like 1

Share this post


Link to post
6 hours ago, mrbigtanker said:

Like to see where this build goes. Looking good so far and like the direction your going. Keep it up. Is there a big import/slash mini truck thing in Texas.

 

 

Thanks man, I am not sure about the mini truck scene here. I have a good amount of experience in the usual jdm/euro/domestic areas but this is a new one to me.

 

5 hours ago, banzai510(hainz) said:

Im impressed. Like to see how or if there is a vibration issue over time with that x member(bolts loosen up?)

 

That's something I am a bit concerned about as well. I will be checking the bolts pretty often for the first few weeks of road testing. I did use lock washers to try and make them as secure as I could. If those don't work I am fairly sure nordlock washers would secure them. 

  • Like 1

Share this post


Link to post

Bolted all the way through the frame?  That would be my main concern unless you also welded tubes through the frame, otherwise relying on the tension of the frame rail to hold the nuts from coming loose.

  • Like 2

Share this post


Link to post

Nylock washers or loctite 243, and it’ll be fine. Looks great already. Start a build thread. I have a dragon green truck as well.

Edited by mainer311
  • Like 1

Share this post


Link to post

I have been looking at that photo for a while, I am going to assume you did what Matt mentioned, you ran 2 bolts thru the sides of the frame on both sides without putting a sleeve them and tightened it up, and it also appears that only them 2 bolts going from the bottom up tie all this together, am I correct so far?

You have also removed the cross member under where the oil pan was on the stock 521 engine, the front of the truck used to be supported 2 ways, thru the torsion bars which the twisting motion was taken up by the torsion bar cross bracket which was weenie as I destroyed one myself, and that cross member under the oil pan that stopped the twisting motion from being transferred to the frame/chassis, now all you have is the frame being sole support and 2 of the cross members are missing.

I do not make comments like this very often, last one I recall was about a drive line that was too long, and that one destroyed the transmission when it started wobbling like a jump rope, this is safe enough on a trailer, but as a souped up driver, well I just don't know.

I have done my share of modifications to the 520/521 frame/chassis, but what I did was stronger than what I took out when I was done, this is not stronger.

  • Like 3

Share this post


Link to post
6 minutes ago, wayno said:

I have been looking at that photo for a while, I am going to assume you did what Matt mentioned, you ran 2 bolts thru the sides of the frame on both sides without putting a sleeve them and tightened it up, and it also appears that only them 2 bolts going from the bottom up tie all this together, am I correct so far?

You have also removed the cross member under where the oil pan was on the stock 521 engine, the front of the truck used to be supported 2 ways, thru the torsion bars which the twisting motion was taken up by the torsion bar cross bracket which was weenie as I destroyed one myself, and that cross member under the oil pan that stopped the twisting motion from being transferred to the frame/chassis, now all you have is the frame being sole support and 2 of the cross members are missing.

I do not make comments like this very often, last one I recall was about a drive line that was too long, and that one destroyed the transmission when it started wobbling like a jump rope, this is safe enough on a trailer, but as a souped up driver, well I just don't know.

I have done my share of modifications to the 520/521 frame/chassis, but what I did was stronger than what I took out when I was done, this is not stronger.

 

I personally haven't removed any cross member under engine, if there is supposed to be one then it was removed by a previous owner. Same goes for the torsion bars as they must have been removed by a previous owner.

 

What would you suggest in terms of strengthening the frame/chassis? I suppose I could use a hole saw and cut a larger hole for the new crossmember mount and then weld a solid piece of steel into the frame section to have additional support and strength

  • Like 1

Share this post


Link to post

There's a stock removable crossmember that ties the LCA pivot points together below the engine...that's what those two holes per side are for.

  • Like 1

Share this post


Link to post

A quick and easy way to get some of the strength back at the through the frame bolt locations is to drill only the outside of the frame to a larger size, like 3/4". Then using a sleeve, butt it up to the inside of the frame and tighten the bolt back up. This will pinch the inside frame plate against the sleeve without crushing the box section of the frame rail. If you've gone this far, you may as well weld around the sleeve on the outer portion of the frame rail.

  • Like 2

Share this post


Link to post

Give it a run down the road.

Things have been altered. So who really knows.

Just pay attention to how the thing reacts.

 

I've certainly been pulled over in worse.

  • Like 2

Share this post


Link to post

could also try boxing in those unusually large angle iron brackets. At the very least some gussets on each side to help with the flex.

  • Like 1

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×

Important Information

By using this site, you agree to our Terms of Use.