snowborder714 said:

This is what Kevin was alluding to earlier in this thread.

For getting both front and rear modified and having the car corner balanced, $3k seems really steep. Corner balancing should cost you around $300. You can send your front crossmember to RobiSpec and he'll modify it for you for under $500 (last I checked). He's already done 3-5 people's crossmembers on this site and has a jig set up for the modification. The only one I haven't heard anyone doing is modifying the rear.

Sorry to thread jack, P.

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That really not that bad (3000 price) when you consider it will be a one off job. It's not a great price either. They will have a lot of time figuring where to and then moving the mounts. Robi only moves the lateral arms . Moving the compression arm is going to be much harder as there is not a lot of room there to do so. I'll bet they will have to fab up custom arms.


Don't forget those of us that had the front x-member done first paid a bit of a premium from Robi.

99gst_racer said:

Adjustable inboard pick-ups will be easy enough to implement. Ask and you shall receive.

I'll have pics of the prototype sometime in December. Just waiting on raw material and my lathe to show up right now. And I have another week of deer hunting yet.

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SWEET!

Time to start putting some singles into the coin jar for this new subframe! If you change or make adjustble pickup points (spacers) i wont need to spend the extra dough. (240SX guys use spacers on knuckles, just a small tip and trick i learned). I thought 3g was over priced, but then i thought about labor time and labor costs. You cant simply cut and move mounting points alone, everything must be changed including knuckles, arms, steering rack raised and relocated as well as building in roll resistance as robi spec does. The engineer(s) that designed the eclipse spent hundreds of hours designing geometry! So when this chassis shop has to do the same thing i see where 30 hours at 100 buck an hour labor comes into play. Although that price includes all material as well doing what i "was" considreing means i would be building one serious car capable of those hard corners (and those pesky evos). that being said, when these subframes come out means ill only have to do the front! cant wait to get one!

it would be really nice if you can build the subframe to accept diff rear ends. easiest one would be the 5 spd 3si rear since its the same gear ratio as stock dsm 5 spd and mounting is very similar to what your working with. just saying cause i know theres a few out there that would be interested on this including me.

What are guys doing for axles to run a 3si rearend in a DSM?

Mitsutalon said:

it would be really nice if you can build the subframe to accept diff rear ends. easiest one would be the 5 spd 3si rear since its the same gear ratio as stock dsm 5 spd and mounting is very similar to what your working with. just saying cause i know theres a few out there that would be interested on this including me.

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Is the rear diff on a 3si any stronger than a DSM?

I know the rear trailing arms on a 1g are almost the same, as there has been some discussions about swapping in 3si rear brakes/hubs/trailing arms. If you swapped in the rear diff, you should be able to use the axles and trailing arms.

Ludachris said:

Is the rear diff on a 3si any stronger than a DSM?

I know the rear trailing arms on a 1g are almost the same, as there has been some discussions about swapping in 3si rear brakes/hubs/trailing arms. If you swapped in the rear diff, you should be able to use the axles and trailing arms.

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Also provided that the hub-to-hub width is the same. I assumed those cars were wider than ours.

99gst_racer,

To answer your original question: Order of importance

1. Quality -Flash hit on this best previously

2. Fitment -Stock gas tank must stay. Direct bolt in with stock control arms.

3. Price -Option it out for many pricepoints and future upgrades (case in point tubular control arms, rear swaybar, etc.

4. Adjustability -Road race, suspension drop, drag race users have different requirements (This starts to impact fabrication rates and price)

5. Weight -Mild steel - realize weight savings at the expense of overpricing the product for some potential buyers = no sale. diminishing returns on pounds lost (though it's a good option choice)

6. Color Options -If you powder coat it, I don't have to, and can bolt in on out of the box the day I get it. I will pay more for that.

7. Shipping size (shipping cost issue vs. garage assembly screwups)

Thanks for the input.

jw4free said:

5. Weight -Mild steel - realize weight savings at the expense of overpricing the product for some potential buyers = no sale. diminishing returns on pounds lost (though it's a good option choice)

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There is no difference in weight between the two materials when comparing like diameters and wall thicknesses. I'm more than likely going to use chromoly. It won't add too much to the overall cost, and it is a stronger material.

jw4free said:

6. Color Options -If you powder coat it, I don't have to, and can bolt in on out of the box the day I get it. I will pay more for that.

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I haven't yet decided if I'm going to offer powdercoating. I have only one place that is local to me and they're VERY expensive, but they do excellent work. I'll ask the group buy participants if they're interested in it and cross that road when it comes.

jw4free said:

7. Shipping size (shipping cost issue vs. garage assembly screwups)

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I have discounted shipping covered. I'm just hoping the final piece will be UPSable (it should be).

jw4free said:

2. Fitment - Direct bolt in with stock control arms.

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Really? I honestly don't think too many people (if any) will desire to run factory control arms with this. There's weight to be saved there too.

If you think AWD dsm's are hard to find, the 3Si AWD cars are even harder. In general, if you make it a swappable setup, I'd venture to say, you'd see someone trying to utilize a 1g in a 2g car or vice versa before they try to run the 3Si parts.

3Si leads to more custom parts. (axle mods) By the time you do that (cost), you might as well put a solid axle in it.

99gst_racer said:

Really? I honestly don't think too many people (if any) will desire to run factory control arms with this. There's weight to be saved there too.

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May be true, but the ability to interchange would leave you with options on replacement if one was damaged. (at the track, on the road, etc) Stock parts are going to be more plentiful for now.

Oh, and one more item worth factoring in:

2.5 - Strength - Forgot for a minute about Twicks69 vid of rear diff 'Pumpkin chunkin'.

Would this also have different toe arms?

Killer! Just what the doctor ordered! Thanks

97gst_spyder said:

Would this also have different toe arms?

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Yeah, the kit will include adjustable chromoly toe arms as well.

Stock control arms on this would be a waste of time.

greengoblin said:

Stock control arms on this would be a waste of time.

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My thoughts exactly. I'd much rather build it around the aftermarket arms, rather than the dimensions of the bulky factory ones.

It's also worth noting that any single part of the arms that I build will be replaceable and relatively affordable as well.

So you're offering chromoly sub-frame with adjustable mounts, toe arms, and control arms for a great price? Man i like this guy already! Are you going to build a front one too?

Not sure on the front one yet. We'll see how this goes first.

After some thought, I would agree that retaining the stock stamped steel lower control arms would be pointless.

Would your package include all the applicable polyurethane bushings pre-installed?

How about the upper control arms, would tubular ones be the better route (with camber adjustability)?

This kit will use aluminum bushings to attach to the frame and the differential. And it will be heims elsewhere, so no poly urethane. It would be up to the end user to fit poly bushings on his/her rear spindles, but this kit would work with the factory ones as well.

I don't know if anyone does an aftermarket rear, upper control arm. I don't plan on making that arm though. I run factory upper arms on my car with an Ingalls kit for adjustment.

The only other option I've heard of for rear upper arm is using a 3g arm. I don't know if there is a weight advantage to using one or the other, but the 3g rear is more tubular in appearance.

99gst_racer said:

Not sure on the front one yet. We'll see how this goes first.

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Sounds like a plan
About the upper control arms, dont most dsmers just use camber bolts? I think for the hardcore track car guys spending a little dough on control arms will be worth it, to most its not worth spending the extra money. to bad these have to be built on a jig, selling a kit for the diyer would be awesome too.

i wish i has pics to compare, the ring and pinion on the 3si is significantly larger than a dsm. and yes you are correct i dont remember where but theres a link out there from one of the gvr4 forum members that swapped out a 3si trailing arm in to a galant.

Ludachris said:

Is the rear diff on a 3si any stronger than a DSM?

I know the rear trailing arms on a 1g are almost the same, as there has been some discussions about swapping in 3si rear brakes/hubs/trailing arms. If you swapped in the rear diff, you should be able to use the axles and trailing arms.

Click to expand...

99gst_racer said:

What are guys doing for axles to run a 3si rearend in a DSM?

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well unfortunately since theres only one company out there that supplys aftermarket axles. you have to run stg 5 axles with the 3si inner cups.

So to sum up the frame 'features' so far.
- Custom control arms
- Custom toe arms
- No subframe bushings (maybe a larger diameter washer welded on top of the mount to disperse forces on the chassis?)
- 4-point soild mounting of the rear diff (6-point for people running the FF cover?)
- Sway bar mounts still of sorts


Sounds like a winner to me!-

I'm interested in pricing, and further features of the subframe.