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RWD 4G63 Subframe mod?

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I was not happy with how the build was going I felt as if everything was being rigged and not to par with my fabrication skills I picked up a mustang 2 front end for 100 bucks and got a plasma cutter here is how the cars sits now going to do more work today when I get new plasma tips.

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I have often wonder if using a different subframe from another platform may be easier than the stock one, the mustang being the one I have thought the most about.
 
That's funny the first build that came to mind was the "sin marks" build.
OP "I like you, but you're crazy"

In for the train wreck
 
should have just spent the money on a old foxbody they can be had for about 1500 or less all day long down here. now you got a pile of scrap dsm that could have went to a better home.

Dont get me wrong i like the idea your trying to be different but come on man.
 
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OMG !!! What a nightmare, you all over the place badly... I feel sorry for you that you in no way wanted to listen to others and even without any diy skills went on with it. This will be an unsafe car and will never pass inspection. Hope you never crash, it won't be pretty... BTW, once you cut the firewall rules require a dash bar. You didn't have to cut the firewall and front end completely off, do you know what you doing ???
 
What a nightmare of "fabrication." As a fabricator by trade, I must agree. If this build stays sub-5k, it's going to be one nightmare of a car. The welds post previously alone have cemented my faith in this car falling apart the minute it starts.
 
I am going ahead with the build regardless of what some people say. What I am looking for is useful criticism like "add a brace there" or "I would do it like this" sort of thing. I don't have a death wish I am simply trying to do something no one has done. I am sorry I cut up a perfectly good DSM, it kills me just as much as everyone else to do. I parted the whole car so far I made $100 on it so its no loss to me.

Here is what I accomplished today if anyone cares... I am going to tie the cage into the front end where the squares are.
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Do you have any sketches of how front end will be mounted/built? Trying to visualize how exactly everything will go there.

So far i'd suggest running the roll cage through the structure you have built already instead of cutting the roll cage and welding it to either side of said structure. That way you are not relying on welds to hold everything, but on strength of metal itself. Perhaps you could even use lengths of U-channel to extend car's existing "frame" (the two square tubes on underside) and weld them to that new front end. That way you will at least have a rolling chassis instead of car on blocks. More reinforcement will definitely be needed, but roll cage will do exactly that (if i am thinking same as as you are).

One more tip (geometry-related): A triangle is a sturdy figure, in other words as long as sides stay straight it can not be twisted or skewed. A square or rectangle, on the other hand, will skew quite easily. That being said, make sure you use alot of braces that form triangles with the structure to drastically increase it's strength.
 
hopefully this gives you a better idea I have frame rails I will be welding into the mustang front eand and to steel plate on the firewall.
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I am going ahead with the build regardless of what some people say. What I am looking for is useful criticism like "add a brace there" or "I would do it like this" sort of thing.

What's the point of useful criticism if you ain't going to listen. I started advicing you how to deal with the front end, you didn't listened, I said not to cut the OEM subframe and convert it into a 2 piece and you still went and did it even when I gave you useful info from another DSMer who did a RWD 1G and did that exact same and it didn't work.. You building a "race car" without even having a rule book and chassis book so you can know what classes permit what type of modifications. Like I said numerous times, I respect you building a V8 RWD DSM, but you just won't listen to advice plus you have no idea how to work with chassis.. I told you numerous times there are key places certain tubes need to react a certain way in case of a crash, its not just tube welding a chassis or whatever you think you doing. You going to add a v8 engine which is a heavy engine and you already cut the front end, which means you need a full tube front end chassis correctly positioned and welded to the cage, those little square tube whatever they are don't look right. You have no clue what you doing, and you ask for useful criticism, but when given such words you take it like ppl are hating your project instead of listening and hearing what others are saying.. If you don't want to listen to us I advice you to take several pics of your build and take them to a professional chassis builder and hear what they have to say. Oh boy, you really stubborn... I pray for your sake you never face a crash or you'll end up in the hospital really ####ed up by the way you building a such unsafe "race car" or whatever you call that...
 
Gabytech all you have told me is not to do the swap and how much knowledge I lack. The reason I started this thread was to figure out how to clear the subframe. I clearly couldn't cut it in half like you said and you were right all stability was lost. So without the subframe there was no need for the firewall. The struts would no longer be used after I got the new front end. I know the cage will not pass tech I am going to have the cage re-welded at all the points to ensure I have good welds for piece of mind.
 
Gabytech all you have told me is not to do the swap and how much knowledge I lack. The reason I started this thread was to figure out how to clear the subframe. I clearly couldn't cut it in half like you said and you were right all stability was lost. So without the subframe there was no need for the firewall. The struts would no longer be used after I got the new front end. I know the cage will not pass tech I am going to have the cage re-welded at all the points to ensure I have good welds for piece of mind.

Retrase all my post. All Ive said it wont be a cheap project like you think or thought, Ive told you the importance of safety and how its wiser to leave the chassis work to a chassis builder and fabricator. Ive told you numerous time over and over the same thing and you wont listen. Do you atleast have someone with chassis knowledge helping you or are you doing all the work yourself ?? Have you research how race cars front tube chassis are built so you can have a general idea ?? Do you even know how to work with chassis geometry, weight balance, suspension travel, etc etc ??
 
Why did you just hack the front off to the firewall? If you can weld that back on. Cut a box out and recess it as much as you need. What you did there is going to kill someone. It's hard to criticise something for you to fix when it's just clearly wrong. No one here wants to see anyone get hurt. I think you cut back to far for you knowledge. Of course you can learn. It would have been best of you just cut off the front to the strut towers.
 
RECARO Presents "Devil's Playground." We head to Lewisville, Texas to meet with the Evolution Dynamics team who drove the infamous Mitsubishi Evo during this year's Pikes Peak International Hill Climb and had one of the most horrific crashes that became a YouTube sensation after both drivers survived and walked away unscathed. Driver Jeremy Foley, co-pilot Yuri Kouznetsov, and Car Builder Kevin Dubois recap the hill climb and explain why it's so important to have the right safety equipment.

RECARO PRESENTS "DEVIL'S PLAYGROUND": THE JEREMY FOLEY 2012 PIKES PEAK STORY - YouTube

Eventhough its a promotional Recaro safety video, they also walked unharmed thanks to the well fabricated roll cage and chassis, a text book example why you don't amateur diy fab safety features in a race car....

I'd like to point out that even "professional builders" get things wrong, and the cage in that car was substandard. I could go into how the B pillar collapsed inward, the seat ripped from the floorboard, the co-drivers head outside the shell of the car, the body panels ripping off because they were secured with velcro, ETC.... But instead I will say this;

If even PROFESSIONALS can get it wrong, chances are you're not gonna get it right if you don't even know half of what they've spent their life learning.
 
If i were to do something like that the framework would have been done differently, using 1" and 2" round tubing (or all 2"), something like this:
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(Credit for model goes to original maker, i only modified it)

Please note that although the framework gives structure strength to handle extra weight/power, car's original body is still there and provides rigidity to entire structure. Basically what being done here is an 8-point roll cage being built, but instead of connecting to the car right before firewall, it connects to new front axle. Also cross-braces underneath provide rigidity to cope with high torque of new motor. Round tubing is chosen because it is stronger than square since square already has nice places for a kink/bend to start: the corners.

(Disclaimer: i am not a professional engineer/roll cage fabricator and am not liable for any damages or injuries that may arise from using of this design. Please contact a professional for professional advice.)
 
If i were to do something like that the framework would have been done differently, using 1" and 2" round tubing (or all 2"), something like this:
You must be logged in to view this image or video.

(Credit for model goes to original maker, i only modified it)

Please note that although the framework gives structure strength to handle extra weight/power, car's original body is still there and provides rigidity to entire structure. Basically what being done here is an 8-point roll cage being built, but instead of connecting to the car right before firewall, it connects to new front axle. Also cross-braces underneath provide rigidity to cope with high torque of new motor. Round tubing is chosen because it is stronger than square since square already has nice places for a kink/bend to start: the corners.

(Disclaimer: i am not a professional engineer/roll cage fabricator and am not liable for any damages or injuries that may arise from using of this design. Please contact a professional for professional advice.)

This cage is still wrong and its not NHRA approved which is what every single track go by rules wise. This cage wont pass track inspection.
 
I read this whole thread and its just really sad what has been going on through the course of this build. Dsm's 4 life it looks like you have no way of backing down because you dont want to fail bro.
I respect your commitment, but who are you trying to prove this to ? Yourself or others to say you have a rwd dsm ?
I dont know how old you are but a man that humbly realizes something is just not worth it, is mature ! Who cares if people will say i told you so, you could just move on.
When i saw the front end cut up, i just cringed so bad.
Butchering up this car to prove a point that you have a rwd v8 dsm says nothing actually. Think about people doing 5k budget dsms with 16gs and doing nicely in 12s, maybe 11s if your lucky with used parts and your own work.
A 460 ford ??? weighs probably a crap load and its still N/a..how will this car make effcient power without spinning and get you a fast timeslip...Isnt that what drag racing is all about???
Lets put aside all the nightmare "fab" that is being done..Is this car worth it so you can go faster. Because you could have pulled off a fast 4g63.
I maybe off topic but even if you put money into v8 down the road, dollar for dollar the 4g63 is more cost effective to take you into 9s for example.
I know you cant back down and i respect you for that but this is too much hassle . Im not hating on you and i support garage gearheads, i did the same growing up but you can listen to Gabytech and other members. They have been there. Safety wise and chassis fab you have to get some assistance man, i hope you not on your own with this build bro. These people want to save you time and money because failing is a big disappointment, hopefully it does not discourage you from this hobby later in life man.
People are actually doing efficient motor swaps like LS1 s because they are proven for example, with this old block you found it seems you only want a "v8" just to say so, even muscle car guys can go faster with smaller blocks.
I hear of 4g63 Datsun,corolla, rx7, going fast because their chassis supports it and swap with minimal work.. This is complete opposite sacrificing efficiency, rather its only to show a v8 dsm...
I hope you get it done and i support you, but ask yourself at end of the day..where do you see this car down the road going fast on v8 mods vs. 4g63...The Fab is a whole another story that i will not even start with, its been covered heavily for you from wise people..
 
Been the front end have been conpletely cut off, the only option to safely bolt the front suspension and engine is fabricating a frame chassis front to back, meaning you have to redo the cage cause the cage needs to be welded to the frame rail. Just like a domestic car. I wish you would have listened from the start and leave the front end alone and just fabricate a crossmember like the one I showed you in my 1st post. The way you building it the chassis will flex and youll never be able to launch in a straight line...
 
Thanks phantom, I think for my own good I should seek advice before I waste my time. I will admit defeat.
I think in the long run the motor is to heavy for the car so much fab work still had to go into the car including the rear end.

Gabtech since I no longer have mcfierson struts could I fabricate the mustang front end into the car and RWD 4g63 swap it that way I can keep the rear end stock. The car will see far less torque. I will cut my cage if needed and what are the names of those rule books I want to pick a few of them up.
 
Thank you for finally listening. Now that cut the front end you need to built it based on SFI chassis. Im more than happy to better guide you towards how to built it the right way. Let me get off from work today and I'll send you useful links. I suggest you go to amazon and buy performance chassis and suspension books si you have a better idea and understand how these work in a race car.
 
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