gmcuajo1

Thanks!
About the CR-V rear trailing arm, you only use the metal part to mount the bearing and the back metal (cast iron) base. Do you think that those parts from the CRV arm are really needed, or a template cut from 1/8" thick steel to mount the CRV bearing will be ok? Obviously reinforced and very well welded, but the steel part that goes on the back of the trailing arm should be used? Does that part does anything different than supporting the bearing?

gmcuajo1

Is this part needed.

quattro

nice work!
Have you performed the obligatory AWD test: full throttle u-turn

DarryCar

I would say absolutely needed. Well, it depends on what you want to do. I've seen people weld the bearing assem right onto the RTA. Wheel bearings do go bad, so if you go that route be prepared to replace a complete RTA and do all of the work over again. The wheel bearing assem bolts into that bracket, and that bracket bolts into the RTA. You could always fab up a bracket like that. Unfortunately Honda does not offer that bracket alone. You have to purchase the complete RTA to get it. Or just rob one or two from a junk yard. That's what I did.

gmcuajo1

Agree with you about the bearing. The bracket can be fabricated in case don't find one, but agree with you, should be easier to find the RTA's on a junk yard.

Why you didn't use the CR-V rear subframe? Wouldn't that subframe be stiffer than welding brackets for the diff?

Did you reinforce in any way the "rear beam" of the car or reinforced the mounting points of the rear lower arms? Do you think they will hold in place?
What about some kind of "rear traction bar"?

Which trailing arm bushings are you using? How they are being able to handle that torque?

Do you plan any solution to correct the shaft angles; put more straight?

tony_2018

Drive it the way you had intended, routinely change fluids and time will tell.

Looking foward to seeing this completed to your taste.

tony_2018

You're looking at the wrong subframe.

DarryCar

Yeah, that picture you provided is of a front subframe. The CR-V rear subframe is stamped steel vs. the tubular steel that I am using to mount the rear diff. Tubular steel should be stronger, but in this design I don't think one is superior over the other. I chose not to use the CR-V rear subframe because I did not want to cut out the Civc rear subframe and body to incorporate it. I really wanted to see what I could get away with without chopping up the Civic. Like I've said in the past, if the design I am utilizing now does not work, I will make the necessary changes.

What "rear beam" are you referring to? If you mean the rear subframe of the Civic, then no I did not reinforce it. Really only the rear mount of the diff is welded to the rear subframe. I'm not sure what "rear lower arms" you are talking about either. At this point I do not see any need for a rear traction bar. Everything is proving to be pretty solid in the rear end. My only worries will be the rear axles, rear diff, and transfer case holding up under launches.

I am planning on using a set of Hardrace RTA bushings. These bushings won't see any of the torque produced by the engine. Just torque from side leaning forces as they are suspension components.

Like I said, I am going with this design until I find that it will absolutely not work. If (when) I brake rear axles, I will go with stronger aftermarket rear axles. If I start breaking those then I will revisit moving the diff back further.

gmcuajo1

I think that yes, the part says "rear beam" but is actually the front subframe.

gmcuajo1

I mixed a lot of questions that come to my head!
The picture is of a rear beam of a civic hatch, not of a CRV front subframe. Is that on the back or the front? Looking at the pic again I think is the civic front subframe.

I was refering to the rear subframe where you have the diff mounted to.

My questions about bushings and reinforcing rear frame comes because I have seen some Technicas being convert to AWD with Eclipse/Talon setups and those guys tend to reinforce the rear part of the car pretty well. Those setups hold pretty well on launching the car (drag race).

What part do think will hold the torque/force when launching the car?

P.S.
Sorry for the mention of those ugly toys!

Below the "rear beam" pic.

gmcuajo1

The "arms" I am talking about. Just using Honda part names...

Besides the bushings and strut assembly those are the common parts of the rear suspension. I saw on the pics that you reinforced very well the rear trailing arm, but what about the other arms?

People tend to put all kind of crazy bars to add stiffness and rigidity to the rear end. On an AWD setup I think the stress on the frame will be greater.

DarryCar

The "upper arm" or UCA is aftermarket and is also my adjustment for rear camber. The "lower arm" or LCA is also aftermarket basically just for looks as it is a nice aluminum piece rather than the stock stamped steel. The "compensator arm" remains the factory stamped steel piece but with polyurethane bushings. I did not reinforce these parts as I feel that they do not see true engine torque. The sole purpose of these three arms is to hold the RTA in place and the rear wheels in alignment. Torsional torque forces should only be seen through the axles and wheels. I still feel that all of the reinforcing we did on the RTAs was a bit much, but better safe than sorry. We'll see how everything holds up...

97civixlx

Hey, I'm currently interested in pursuing an rt4wd honda build as well and I've pretty much read all the forums about this too. I don't want to thread jack but I got a quick question. Earlier in the thread it was mentioned that there were builds that kept the crv rear trailing arms. I think I've only seen one build that used this, but it wasn't explicitly said that it kept that, only that they used the crv rear subframe and some crv parts.

https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/check-out-my-awd-civic-eg6-2618576/

The LCAs in that thread definitely are not crv LCAs. So I'm curious to how he got his set up to align. I'm perfectly fine too of the car sits a little higher too. I've never been a fan of slammed cars, but a lowered crv suspension on an ek doesn't look too bad imo.

Does anyone have any links with crv rear trailing arms on a civic?

Anyways, good job with your build! It's always nice to see when someone actually pulls through

atanatas

Just another perspective. it was to be quick note but no way.
In fact all bushings of the civics suspensions experience stress when you break. even those on the struts,
the wheel is intending to move back, the car inertia keeps pushing front. Rotational forces, skid, torsion, blah blah. Thus said, all the bushings are there to absorb all the shock (do not confuse with dampening) forces created by wheel opposing the inertia and transfered to the TA.

When you accelerate all the same forces vectors are inverted (with some change of angle)
so on wheel goes front, car try to stay still. 2nd law of motion again.
is the wheel tied to RTA. YES
do you need stiffer bushings, by above reasons yes. in real application? Maybe not.
how stiff?
no answer to that, it depend how much torque (not Ponies! But NM or pounds Whatever) You apply to move certain mass in this case the rear of your car (600kg OR more) with the rear diff.
Now on the other hand.
All AWD and FWD civics or Crv main rear (the big fat tick thing) bushings have identical stiffness as are also mostly interchangeable. Strangely wagon also use the same bushings no matter is 50/50 power split as most people believe.
Point to follow.
The ingeneering by design, is only to use like a 2/5 of the total available engine torque to power rear wheels, really for a small amount of time at start of motion, even though forces acting at that moment are huge compared to if already in motion, still not that much of a stress.

When you exceed with times and you fully lock to 50/50, suspension is more stressed.
now 400 NM tops on a busty boosted engine,
200+ (100NM or more additional force because in start car lacks inertia, try to stay still remember?) NM at the rear if suspension is rock solid.
and the rest to power the front.
Now this is if you start in a 4 gear. multiply by the actual gear ratios at first gear. and you easily get way up to massive torque.
this changes exponentially (complex formula)once you start moving forward.
just look for video in www. is as usual self explanatory.
So the kind of wheel not moving idea is only if you solid mount the trailing arm with a bearing.

Now, Do you need stiff bushings?
My answer to this question would rather counter question.
Yes, you need stiffer bushings for a rice, drag or whatever other than didy application.
and that is why race cars rely on polyurethane bushings, and even bearings, traction bars, whatever hardware keeps the wheels at place under all conditions minimize to practical 0 the possible distortions implied by mother nature, no matter the chunks, crack, snap noises you hear when driving it. it doesn't matter as traction and breaking are so instant and direct.
​​​​​​​For stock NA or mildly powdered booby kandy you get away with the stock, only replace with the OEM and clear to go.
We all look for comfy didy right?

tony_2018

I suggest you cross reference part numbers from the crv to the rti.

atanatas

EU not same, not bolt nor interchangeable.
Both look massive but different cast, compared to civic RTA
Different bearings corresponding the different size knuckles to fit in. Straight on from my build, wagon rear hub was 34mm at the bearing. do not know the CRV hub OD, Mine was also machine reworked. No bolts on option.
When was looking to buy the RTAs also noticed different mounting points for LCA, UCA,
​​​​​​​LCA point on CRV was more back compared to wagon.
UCA point was further up and front.
slight differences, on the European versions.
overseas may be different.
Rather phisically measure will solve better the mystery.

DarryCar

Got the exhaust done and it is so much quieter. I forgot how much I like the sound of the Thermal R&D exhaust system. Now I can actually hear what is going on with the Civic and everything is sounding good. I can hear the rear diff humming through the body of the Civic, but that is to be expected. A little louder when it is locked, but nothing crazy. I dropped the Civic off at the exhaust shop and just let them do their thing. Didn't turn out exactly how I wanted it, but there is also very little room for 3" piping under there. I wanted the exhaust to go up and over the driveline to the passenger side and snake through between the rear axle and the body, but they decided there wasn't enough room to do that and just ran it under the rear subframe. It was probably much easier to do it that way too. I don't like how it covers up the sway bar brace now, but that's just what I am going to have to live with for now. It looks really low to the ground too, but it is only that low at the subframe, so it shouldn't be too much of a problem.












You can see how little room they had to try to snake it through between the axle and the body. It's getting there. A few more drives and then it's off to the powder coaters for all of the parts. It's not even tuned yet and it had been fun to drive!

atanatas

Tight,
oval pipe may gain you an inch of clearance under the beam.

Tyler Dirden

iTrader: (3)

This has been a marvelous work of art! The finished product has well been worth the effort in both appearance and very likely performance.
You have a real show stopper there. Well done.

2LEM1

iTrader: (1)

I'd just run a resonator under the car and dump the exhaust at the rear diff... snaking it under the subframe like that is just asking for trouble.

Awesome build though.

tony_2018

If you add bushings to the rear dif mounts you can hear the rear dif less

BigBerz

Why run it out the OEM side? Can't you run it out the other side and then it won't block the subframe brace? Agree with above post too oval pipe will be a life saver (although costly) and save some clearance for sure.

Berz out.

tony_2018

Berz back in and take a look at the pics. Your answer can be found there.

BigBerz

I'm looking but I can't see why it has to turn right (looking from the rear) after the subframe rather than turn left and have a quick bend to get it out the left side?

Berz out.

DarryCar

It didn't matter which side I ran the muffler and tailpipe out of. There wasn't enough room to snake 3" piping between the rear axles and the body. Either way, the piping was going to have to go under the rear subframe. It's hard to tell from the pics, but they did "oval" the piping right were it crosses under the rear subframe. That gave it a little more clearance. I also wanted the tailpipe exiting on the factory side because there is a cutout on the bumper cover for the tailpipe on that side. I can't stand when people remove their tailpipes or go from dual pipes to single pipes and leave that cutout empty. Had to be done this way for now. Had to move on to other things for now with this project as well.