Allwheel Drive Omni GLH SRT4

[rbryant]

the caravan rear beam doesnt look to bad either for making trailing arms that attach to it. it has 4 huge bolts that normally attach the leaf springs to it and they'll work well as trailing arm attachment points.

the center part is basically a pipe so cutting that, pressing in a piece of tubing in the center of the cut and welding it back up wont be hard either depending on how much it needs to be narrowed. i gotta take a tape measure out to the garage and measure the difference in length from brake disc hat face to brake disc hat face.

i havent measured it out totally, but it shouldnt be too bad to make a lower perch for the stock springs/shocks on non-l-body cars.

Brian

You should actually check the measurement vs. the stock specs.

The charger/omni rear is 55.7" with stock drums (but it would be more like 56.1 with discs which are wider)

And the other K based platforms are 57.6 (57.2 with drums). (1.5" wider than the omni/charger)


Interestingly newer caravans are wider than the old ones and their rear ends are much wider than their front ends.

The 2000+ caravan rear track (both fwd and awd) is supposed to be 64" and the front is 63"

The 95 and older caravan rear track is supposed to be 62.1" and the front is only 59.9! (2.3" wider than a kcar)

So it looks like you would cut:

95 and older AWD van rear:

6" out of the rear for an lbody
4.5" out of the rear for the GJKHP body.


00+ AWD van rear:

7.9" out of the rear for an lbody
6.4" out of the rear for the GJKHP body.

-Rich

[Aries_Turbo]

im going with actual measurements because im using wheels that are already on my k car and have already been on my daytona before so the calculated measurement may be a little off if the van wheels had different widths and offset. they are dual bolt pattern american racing wheels. 15x7 with both 5x100 and 5x114.3 so i dont have to mess with hubs at all. plus they clear the van rear discs with ease.

brian

[rbryant]

im going with actual measurements because im using wheels that are already on my k car and have already been on my daytona before so the calculated measurement may be a little off if the van wheels had different widths and offset. they are dual bolt pattern american racing wheels. 15x7 with both 5x100 and 5x114.3 so i dont have to mess with hubs at all. plus they clear the van rear discs with ease.

brian

Yea it is good to measure and of course that is the real truth.

I would expect that the measurements are close to these which makes them a really good rough guide and sanity check on your measurements.

I once cut 2.5" out of a kmember that only needed 1.5" cut out of it because I used the wrong measuring points and didn't think to look at the actual track differences...


-Rich

[5.8 L Import Eater]

Awesome build up Carlos.

Now all we need are some videos of the monster cruising the streets looking for trouble....*L*

I am very excited to get on my GLH this next spring. This is going to be one of my most anticipated projects yet.

Chris

[omnigoestohell]

Wow... how did I miss this? Awesome, good job Carlos. Any idea on a curb weight for this thing once completed (with 4wd, 16v and the brakes?) It can't be light, but probably lighter than almost any other 4wd out there.

[lotsaboost]

It can't be light, but probably lighter than almost any other 4wd out there.

It's actually lighter than you think. The rear stock suspension was almost twice as heavey as the ladder bar/dedion setup that I fabbed up. So I only gained just a few pounds in the rear by adding the the diff, axles and driveshaft. In the front, the PTU weight was cancelled out by using the super light Mazda Miata battery(it's puney & it's got 465 amps). I wish I had actual #'s to show exactly how much weight but I simply can't find a lot of that info. I moved and sold a lot of stuff in the middle of the project. However, I do recall calculating everything and I was very close to my target goal of 2,500#'s. I'm not too worried about it anyway, soon I'm taking it to the scales to get the actual weight and work with that. I may or may not lighten it some more. I was going to go all out and just make it a really light race car but I really enjoy driving it on the street. And, if I reach my goal of 500 WHP this summer then 2,500#'s should be good enough to propel it with some good 1/4 mile #'s if the drivetrain holds up.
Carlos

[zin]

And, if I reach my goal of 500 WHP this summer then 2,500#'s should be good enough to propel it with some good 1/4 mile #'s if the drivetrain holds up.
Carlos

No kidding there! 2500ish pounds + AWD + 500WHP = Mid 10s!!!

Mike

[t3rse]

on street tires...evos run 9s with 600 and stickies.

[omnigoestohell]

Mike, that of course assumes a stock 2001 Caravan AWD system could handle 500hp for an entire quarter mile..

Still wicked cool.. it will be awesome to see..

[zin]

Mike, that of course assumes a stock 2001 Caravan AWD system could handle 500hp for an entire quarter mile..

I'm afraid Carlos will get to prove strength isn't an issue before I am able to do so.

Mike

[Aries_Turbo]

yeah that stuff look pretty darn beefy.

Brian

[Ondonti]

Yup. Stock tank. Moved it to the rear. It's a cheap Ebay unit. I had to remove a little metal of the front to clear the suspension.

That's going to be very interesting to see how it's going to turn out with the early van setup. How far are you into it?

A 3.42 rear would be a sweet setup for drag racing, connected solidly to the PTU with no viscous coupler. Heck, if you can live with the binding, then you could also drive it on the street. If you can fab the dog clutch into the drivetrain you'd have a mechanical version of an STI's system. You could engage it any time you'd want 50/50 torque split. Man, the more I look deeper into this system the more versatile it becomes. There's just all kinds of options with it. It's going to be cool to see the finished products of those who have aquired parts and have already started it. That's why in my initial post I requested that we start an AWD section.

Carlos

I wish I knew about the omni fuel tank :P
Oh well, I already have my fuel tank replaced with a cell.

Reason for going with a 4 link is that my toyota fabricator friend used to be into building crazy off road stuff and said that a ladder bar would promote weight transfer to the rear and lift the rear tires. He also said the longer the ladder bar, the worse this would be. yours is pretty dang short so maybe not a big deal.

RIght now I am sorta wishing I moved my Fuel cell back a bit farther. I want to move my rear end as far back as I can. I might not be able to move it at all but oh well. lengthening the wheelbase would be a nice addition and the 4 link wouldn't mind being a little longer.

The dog clutch would be fun to add, I just think it will be "plenty" of a project already. I am most scared about getting the driveshaft done. That might get expensive as i want a carbon fiber one made locally. My driveshaft is pretty much junk thanks to a forklift.

I picked up the 10 bolt 3.42 LSD 7.5" 2000 Trans Am rear axle in November. Weighs 199 pounds. Got some used wilwood dynalight 4 pot drag brakes for 300 bucks and they will save me 29 pounds so my rear end will only weigh 170 pounds with brakes.

So even with a solid rear axle, My complete rear axle will weigh less the the caravan stuff. The Pre 2001 coupler + rear end + axles weigh 147 pounds without brakes or solid axle or swaybar weight. So probably well over 200 pounds as a full package.
I have figured out that my car will gain about 140 pounds total from the AWD swap.

I would like to roadrace in the future but I realize the limitations of all the unsprung weight. Who knows, maybe we will be wrong and our transfercase will turn into a pile of crap. The only thing that bothers me is that the pinion/output shaft of the transfercase does not have multiple bearings like I have seen in some other T case's. Worried that it will flex and disengage from the ring gear.


With my setup I have been considering running huge wide tires in the rear and more reasonable tires in the front (same diameter) but I have come to the conclusion that if I am going to drag race, I will put slicks on. If I want to goof around in the car, I will just have 4 225's on the car and probably no car will be able to even remotely hang on the street. Giant rear rims/tires would be incredibly expensive, and heavy too.
Very interested to see what kind of 60's I can get at the drag strip.
The DeDion will probably be able to pull off similar results.
My rear end is not incredibly strong, but with 50/50 awd it will only see half the power, and the front tires should help prevent the axle housings from bending during the force of a launch (which causes the ring gear to misalign with the pinion). Also, my car should only weigh 2350 without driver with awd. F bodies weigh 3700 with driver and put all the weight of the car on the rear axle housings.

Huge problem with IRS AWD cars is that when they launch (soft crap suspension) the front tires go massively postive camber, and the rear tires go negative camber. So the faster cars drive to the line with huge front negative camber and serious rear postive camber. Obviously there is a detriment to traction once the car levels out again.


Just to let people know, there are very few street tire AWD's that actually get the numbers some of us are hoping for. And the ones who run really fast are running R compound tires at the drag strip. I think that is silly. You might say you drive your car home but, those guys probably park their trailer around the corner to prevent wearing out those tires.

4 small 24.5x8" REAL slicks should be great thought. For some reason the AWD crowd are semi brain dead and almost always use DOT slicks, which are just as dangerous on the road, and are less sticky.

My big financial worry is my rear coilovers. I cant afford the double adjustable qa1's that I want. 300+ each. People are saying that a good awd rear suspension should be able to adjust both bound and rebound damper independently.

I bet that kind of rear shock would be a HOOT to adjust at the track.

How long are your coilovers? The total height of the ones I want is like 13.5" with a 10" spring. In the end I might go with single adjustable which are almost half the price and skip all the fun.

[Ondonti]

I wanted to mention for those having different awd ideas.

To make my 64" wide rear end work, I am going to buy Strange brand GM housing flange ends, shorten the housings and add the flange. This flange accepts a Strange brand wheel bearing (no need for c clip eliminators) that presses onto the axle. The Axles will be Strange brand custom (or the other company if they quote me less). I have had a real tough time about bolt pattern. I have decided since I am getting custom axles its probably not going to be a big problem to ask them to just cut both 5x100 and 5x114 patterns. That way if I ever decide to go with a 114.3 wheelset, I just need to hammer in some studs and swap the front to van parts.
The bearing will be held into the new housing end by my brake adapter plate.
Not sure if things will work as smoothly as I hope, and I certainly can't afford the parts right now but that is how it is going to be. My rear end setup is certainly not as affordable as i originally planned. If I did one again I would just go Dedeon, but I think this setup will be fun and probably not mind if I remove the front driveshafts for some RWD thrashing.

In the end its looking like a 2,000+ dollar project JUST for the rear end setup, and thats only if I get a hookup on the driveshaft (possible) and buy the cheaper coilovers.
Financially I couldn't commit anything until I talked to vigo about used parts and found the used brakes on ebay. So I have committed over $600 to the $2000+ budget (300 something for the rear end)

I may cheap out and just reuse shocks and springs that are on the car currently but that will only save me about 500 bucks but that would leave me only 900 dollars short that I would need to save. The 500 or so dollars in axle costs cannot be avoided or cheaped out on for what I want to do with the car, the 4 link kit will probably be cheaper then me sourcing parts and building my own brackets. I budgeted 200 for the driveshaft but it may cost near 1000 if I get screwed. So 2000 may turn into 3000.

So because I don't have a shed full of RWD parts etc, this is really a bad financial decision. DeDeon will pretty much just require some axle shortening at a professional shop.

There are also about 700 dollars in upgrades I can do to my rear end (fancy lsd and a bunch of fancy support covers, axle tube braces, non crush pinion sleeves) and well, I hope the rear end holds together without them.


I don't think its a smart way to go on a Rampage or anything for the matter. 3.42 rear ends can be found in Tacomas also but....ick. I could cheap out and save some money by having a local shop shorten the axle but then i would have sort of a sub par c clip rear end and still have blown a crapload of money. If I am going to blow money, I might as well get something nice/quality.
Find any way you can to use the stock rear parts.


One thing I dont understand. I thought only the 2001+ rear ends were 3.45 ratio? If the early rear end is not 3.42 then I would have failed on my original idea to just use the rear end without the VC or dog clutch (save 60 pounds). To be honest, the only reason I went this route was originally to have LSD options but looking at the cost, I feel pretty silly. I have already envisioned things in my mind so i want to finish the project. I wanted the LSD because the 700-1000+hp 3000gt's are all worried about that stuff and they are using MUCH larger tires. 275 wide DR's all around on some of them.

[lotsaboost]

He also said the longer the ladder bar, the worse this would be. yours is pretty dang short so maybe not a big deal.

Yup, that's another reason for the ladder bars. It's compromises for a RWD drag car do not necessarily apply to our application. As you mentioned, it's length is nowhere near that of a RWD car, it's fully adjustable with the rod ends, you will not transfer anywhere near the gobs of torque to the rear that a prostreet type of big block or any V8 for that matter to the rear of the AWD rear. Even if you had say 500 lbs. of torque, you would only be applying half that to the rear. And, this being AWD, the weight transfer is not the same as it is in a RWD vehicle. You are, in a sense, "pulling" as you are "pushing" the car simultaneously.

My complete rear axle will weigh less the the caravan stuff. The Pre 2001 coupler + rear end + axles weigh 147 pounds without brakes or solid axle or swaybar weight. So probably well over 200 pounds as a full package.

Yea, the early Caravan setup is a moose. However, for all it's weight, it appears to be a pretty stout system.

How long are your coilovers? The total height of the ones I want is like 13.5" with a 10" spring.

I believe they are 14.75". They're not staying. The springs are cheap ebay units, they're already sagging. I fabbed them from stock shocks. I also inquired about the QA1's. I could get a set for my spec's for about $400 bucks. I believe it's worth it though, with their adjustability you could really set your suspension up to just about any eracing environment. And, I'll be keeping the car for a while.

Anyway, this looks like it's going to be a really awsome build especially with one of your nasty 3.0's in there. Definitaley one of the one's I'll be watching for a while. And to think, I almost got out of TM's to go back to the V8's.

Carlos

[turbokid]

A moose? never heard that expression LOL
Glad the caravan set up seems pretty stout.
Cause thats what I have

[Aries_Turbo]

yeah that caravan rear axle assy is HEAVY. I dont like lifting it up lol. oh well, im still using it. just shortening it for simplicity's sake.

plus when i make my trailing arms, they will bolt to the axle where the leafs attached. that will make things even simpler.

brian

[Ondonti]

How much would you sell those coilovers for? Do they have eyelets on both ends? I don't really know L body suspension parts. i was looking at 13.5" ride height qa1's so those would be good enough since the 4 link kit has adjustable bracket holes.

I am okay with sagging parts because I am so much farther behind then you. I want to be able to fit things up.
Double adjustable qa1 looks soooo sexy. Rebuildable, and since its a universal part, no problems with "oh, we don't want to make new tooling for your blah blah blah"

[lotsaboost]

How much would you sell those coilovers for? Do they have eyelets on both ends?

Hmm, haven't really thought about selling them. I guess if someone really wanted them I'd take $75 bucks for both. It'll be a while before I get the good ones though. Also, they have the standard L-body stud mount up top and the eyelet on the bottom mount.

Double adjustable qa1 looks soooo sexy. Rebuildable, and since its a universal part

Yup, and they've got several options with sizes and mounting.

[rich tideswell]

bumping this

[5.8 L Import Eater]

Almost 3 months and no real updates?

Any videos of it driving? I am so excited, and looking for AWD parts currently.

Chris