Body/Frame Reinforcing

[jah_fyah 0]

Hi Guys,

I've been on here for a while just gathering all the information I can without asking dumb questions that have already been answered or not using the search function. I have finally come to the point where I need some guidance. I know that a few people have done work to make their sub-frames hold up to the additional power that is being thrown at it, but I am trying to go the best route at making sure my car doesn't fall apart once everything is up and running.

 

I've seen this thread and I am wondering how the hell his rear end or car hasn't come apart when I know most others are screwed once they start making some real torque.

 

http://jzxproject.com/bbs/index.php?showtopic=626

 

 

 

 

I've looked him up on youtube and the car is in the 8 second range now. Does anyone know the suspension setup that can handle that in a cressida?

 

 

 

I've seen a post with a reinforced sub-frame as well as Gordo's engineering and I want to know how much beating you think these design can handle?

 

 

Sub-frame in Japan that was reinforced

 

http://jzxproject.com/bbs/index.php?showtopic=9081&hl=ramblings&do=findComment&comment=137372

 

 

 

Gordo's

 

http://jzxproject.com/bbs/index.php?showtopic=8913&hl=ramblings

 

 

Gordo's design looks to me to be far more superior to the Japan design.

 

As for the rear end, Is an upgraded MK3 diff good enough or is there a way to fabricate a MK4 diff into the X83 sub-frame? A local shop here says that it can be done, but I want to know is it worth it.

 

And Lastly, has anyone heard or tried foam filling??? I came across it during research.

 

http://www.subrosa.com.my/automotive_foam.html

 

Any input from the JZX community will be appreciated.

 

Bless

[jah_fyah 0]

Apparently 1JZ747 was for sale and he listed the specs, but no frame information and it has a custom suspension whatever that means....

 

http://www.toymods.org.au/forums/toyotas-sale/35863-1jz-747-9-sec-drag-street-car.html

 

1991 toyota cressida grande

engine
1.5jz conversion
balanced crank
forged pistons and rods
titan harmonic balancer
272 cams
Trust cam gears
bosch coils and leads
6boost turbo manifold
twin tial wastegate
custom 3.5 inch exhaust all coated.
GT42R turbo
custom aluminum cooler pipes
600x300x90 SPEARCO intercooler
1000cc rochester injectors
custom NX nitrous system, direct port
Microtech LTX12S with X6box ignition 4 bar map sensor, data logging enabled
EGT meter

driveline
custom 2 speed powerglide
4500 stall converter
custom 3 inch tail shaft with drag unis
transbraked
weld up diff

interior

ANDRA teched 6 point rollcage
custom carpeted from rear window to ffire wall to comply with s/rwd regs
fixed back ADR approved bucket seats
boost guage, trans temp, pil pressue
microtech dash
stewart werner shift light
eboost2
RCI safety harnesses
B&M pro rachet shifter

car had been lighted, no longer has sound deadner, air con etc.

other items

RCI fuel cell
twin boch 044 fuel pumps with fuel filters.
custom parachute mount, removable parachute.

custom suspension coil over arrangment
custom bushes
custom sway bars.

custom big brake conversion
r33 calipers
BA falcon rotors
green stuff pads
bradelinds

[Gordo 0]

If you make an auto mushy enough, it won't break much.

I set mine up so that the converter was locked as soon as it got to 5k in first, and I was snapping off ARP crank bolts, and the converter bolts.

And who knows what the sub-frame on that car was really like, or what he did to it, or how many times things broke.

I don't know if I would go as far as putting in a larger diff, as I know there are a several 700+ HP supras runing the 8" still, but they do destroy subframes, and it's built better than ours.

So I suggest to at least address that.

You might note that Toyota has went to using tube in some of their subframes now, and people sell complete aftermarket tube subframes for other cars.

You should also search Yahoo-JP auctions on what people are selling to beef up modern cars, some of ot is more than interresting.

Unfortunately, there is nothing for the X8 any longer, except for silly bars (go between the rear bumper mount bolts, and between the rear shoulder belt mounts).

I think of you go to a MkIII diff housing conversion (and that is so fucking simple that I can't understand why anyone would buy a 'kit' to do it) and beef up other points on the X8 rear diff mount area, you will be good.

I was toying with the idea to cut mine appart in the rear to get 4 mounting holes so that the Supra rear cover could be used, but my power level doesn't justify it.

As far as foam filling, yes, it does help, a little, but........

Even a 6-point cage with side bars would do so much more.

I might foam fill my skirts, and nose, to help keep them togeter, but that is about as far I would go.

If you want pictures of some of the modern bolt-on chassis bracing, send me your e-mail address, as photo bucket is getting way too hard to use to put them in there.

[MikeRN 0]

I remember 1jz747 used bilstein shocks either mx83 or ma70 rear/ sw20 or rav4 front and custom made springs. he didn't run coilovers.

[Jspec603 0]

Shock/springs, IMO, are better for drag. Get something softer in the rear so the car can squat and gain traction. Also, set the rear to slight positive camber so when it does squat, the tire will sit square to the track/road surface.

Gordo's subframe, to me, appears to be the better choice for reinforcement. However, I'm curious how much weight was gained in the process. I'm sure it's in your thread Gordo, but I'm too lazy/tired to go look right now.

[jah_fyah 0]

Gordo, My setup right now is a built R154 and going to be a built 2JZGTE. The only thing keeping my power level down will be my turbo. I have a MKIII LSD diff I can stick in, but just wanted to be sure that it was the best route to go. As far as what you said

 

toying with the idea to cut mine appart in the rear to get 4 mounting holes so that the Supra rear cover could be used, but my power level doesn't justify it.

 

what power level you think justifies using the whole MKIII housing opposed to using the X83 rear cover? Don't want to sound too dumb here, but does that mean I can get a bigger size diff inside the housing if I use the rear cover off of the MKIII? As far as the tube frame goes, I'll send you a pm.

 

Thanks again!

[Gordo 0]

The only thing to be gained with the MkIII cover is spreading the load out over 4 bolts, instead of 2, and a finned cover.

If you are going after big boost numbers, like 25 and up, and if you plan on running really big/sticky rubber on the back, then it would be good.

But for drifting (intensionally sliding the back end), or playing on the street, and treaded tires (street rubber), it would be a waste of time, since 450-500 hp is all that they will take.

[MikeRN 0]

at what hp levels does the subframe crack?

[Jspec603 0]

From what I've heard and seen, it could be at any HP level. Even with a stock 7M.

[jah_fyah 0]

Talking to my boy last night, I told him about what Gordon said it looks like the best option to not have to worry about the rear subframe breaking is to go with a custom tube rear subframe. Now the next thing for me is to decide on what material I am going to build this thing out of. He recommended DOM .120 or Chromoly; the latter being a heavier option. He is also going to fab a six point roll cage as well. I guess that will be the only way I won't have to think about the chassis twisting or cracking with any amount of hp that I can throw at it. Once this is done, my weakest point will be the R154 and I'm ok with that.

[Gordo 0]

When you do, make a jig, as you could possibly sell a few (if they are not a fucked design)

[ROBAPHENT 0]

Shane's X8 uses a solid rear end it is no longer IRS.

 

I will post pictures of my kids heart rear subframe with added rear brace it did not need it sence they did have bracing around it but i had a spare brace so what the heck.

[ROBAPHENT 0]

Need to resize my pictures before i can post them i have been advised by the forum.

 

Will get on to it after work.

[jah_fyah 0]

Thanks bro. Any info will be a great help. No need to re-create the wheel if something good is already made. If this comes out good, we might have a new after market part for the X8!

 

Robaphent - Your pic "Cisco Kids" leads me to believe you a Network Engineer? I am and whenever I see Cisco I see family! Lol lmk

[ROBAPHENT 0]

 

 

Sorry about picture size i was to lazy to resize so just uploaded myself.

 

 

Ciscokids is more of a small project of mine pretty much help the better X8 in australia out with parts and hook ups. grow the kids who know there shit while the noobs can fuck off. not in it to make money just get decent x8 exposure.

 

I do work in I.T how ever So it does relate to myself and my nerds it also a song of How high done by cypress hill so all has some sort of relation to me

[4DRSPRA 0]

if you turn the welder power and wire feed up you would get better welds, also it helps if you clean the area before you weld. you have some pretty nasty porosity in one of them photos and i would say go at it again (clean it up with a grinding/cutoff wheel first)

 

this shit looks like solid ideas though, what about just adding gussets to the 90's how do you think that would effect lateral strength

[DiscoShit 0]

Im not sure he welded that him self. I think thats a subframe that was done in japan hence the welds.

[jah_fyah 0]

Just a quick update, I am going with the customer rear subframe. I ordered the round tubing (2 10' tubes) and will also getting a Ford Cobra differential to put in it. Contemplated about going with a MK4 diff, but the cobra rear end seemed to be the better option after research; less expensive and cheaper to change the gearing ratio's if needed. Not sure how long this is going to take, but once it is done, I'll be posting up pics.

 

Thanks again fellas for all the input.

 

Bless

[Gordo 0]

That isn't that aluminum pos that someone else here tried, and blew appart already, I hope...........

 

And it seems hard to figure what other gear sets you could possibly want, that are not covered by the ones available for the Toyota 8", that are easy & cheap from 3.7, all the way to 5.29.

[ROBAPHENT 0]

Yeah as above was all done by Kidsheart Japan.

 

and yeah why would you not stick with a toyota diff? good for 9sec drag passes/Drifting and ratios coming out the ass and all rather cheap if you look around.

[1JZ747 0]

Shane's X8 uses a solid rear end it is no longer IRS.

 

I will post pictures of my kids heart rear subframe with added rear brace it did not need it sence they did have bracing around it but i had a spare brace so what the heck.

 

 

my rear end is still IRS, it simply has some urethane bushes installed and the diff cross member is strengthened. ive put photos up on my 1jz747 racing facebook page in the last month or 2.

 

the factory rear end including stock diff with welded up centre is holding the horsepower just fine.

 

regards

 

Shane.

[Jason 0]

Thank raptor jesus this guy is finally in here. Shane. More videos. NOW!

[1JZ747 0]

I've been here since the beginning posting under dragme logon, just can't remember my password

[Kyle 0]

your car is fucking awesome. MOAR PICZ NAOW.

[DiscoShit 0]

^ this x10000000