So GGSX Diff w/ secondary gear WORKS! 88mph in 5th gear @ 3k!!!!!

[cheekychimp]

The VR4 gears will not be as strong as dog tooth gears but provided you are not launching hard that shouldn't be an issue. I also don't think the GGSX diff is going to be a real problem, but I don't actually know if you can use the GGSX Diff with a 4 bolt rear end. If you can, it should still be a pretty sturdy setup for the street. If you are going to get the transmission beefed up at a later stage you could still consider using EVO III gears for strength.

Also how do you get 88 mph, according to the tables isn't it 77 mph at 3000 rpms using your stock 0.666 ratio VR4 5th gear or are you going to fit an EVO III 5th gear?

 

[alansupra94]

Oh I have 225/40/R18 tires. So that means my diameter to 26.

 

[cheekychimp]

/ubbthreads/images/graemlins/banghead.gif I wished I had just asked you that earlier. I've been trying to work out for days why you kept insisting that you'd get over 85 mph at 3000 rpm.

 

[alansupra94]

Lol its cool man. I realized that this gear box will actually be stronger because I won't be banging through gears as I can make pulls in 3rd that I would normally make in 3rd and 4th.

Pretty sick stuff here.

 

[cheekychimp]

Yeah I am really interested to hear how you do get on with this, I was pretty disappointed at not being able to do this on my car although I think that possibly as things ended up with the combination of all the parts I have my setup might actually be more suited to Hong Kong. I did the math and with the custom 5th gear in the GGSX/EVO VR4 hybrid transmission my 5th gear speeds were just plain stupid. For starters I don't think the car would have been aerodynamic or powerful enough to take advantage of all the gear I had and even if it was in Veyron territory I CERTAINLY can't think of anywhere in Hong Kong that I could have realistically explored a supposed top speed of between 250 and 300 mph.

I think my 1st and 4th will be much easier to use around town whilst the 5th gear will act more like an overdrive, still giving me the ability to cruise at our highway limits at under 3000 rpm which should be ideal. If it is a straight cut gear however it might whine a fair bit /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/frown.gif

 

[curtis]

Ok one thing not brought up is the pitch and angle on the gears your miss matching.. They might fit together but will they live. I remember something about a trans thread and one of the Oceania guys says something about this when using old evo parts. To tired to wrap my head around this right now but I do remember something about this.... maybe it was when I posted about the 3.30 1G automatic rear diff I out in the shop I'd like to use if I could find a front diff.

 

[cheekychimp]

Curtis it was Tim (BrisVR4) and he was talking about the EVO III Centre Differential. I still haven't got to the bottom of this. I swung past Ken's shop today and he was fixing up a customers EVO III gearbox. The owner couldn't get parts anywhere and so Ken was swapping in good VR4 gears. He says he has been doing it for years and has never had an issue so I just don't know. I messed up once doing stuff like this and wrecked a front ring and pinion in the 8G VR4 and it happened REAL QUICK which suggests to me that if this was an issue Ken would have found out about it by now /ubbthreads/images/graemlins/dunno.gif

It confuses the hell out of me. I know the EVO III front ring and pinion is one tooth different from ours which is why if you use the EVO III front ring and pinion you MUST MUST MUST use the EVO III transfer case which is NOT a 1.09 ratio but I have never heard of issues with the diff. If you go looking for an aftermarket centre diff for a VR4 you will find a lot of the parts offered are actually listed for use in an EVO 1,2 or 3. So if anyone is running an aftermarket centre diff I'd be real interested to hear if it has given them any issues and if they can confirm if the diff is VR4 or Evo 1,2 or 3 specific.

EVO 1 & 2 gears are completely compatible with a VR4 box (well an RS/Evo VR4 box) as long as you use the 3.909 ratio rear end. So if the diffs work in EVO 1,2 and 3 cars I can't see where the difference would be. It bothers me that Tim said that because he knows his stuff and I've got a damn expensive hybrid box sitting bolted up to my car with a mix of EVO III, RS/EVO VR4 gears, EVO III diff and a 3.545 front and rear ring and pinion.

Is the front ring and pinion what drives the differential?

Edit: Ken has done the 3.307 swap as well Curtis and says it rocks on the highway. I think you need a JDM RVR gearbox. I'll ask him again when I see him what are you looking for exactly, just the front diff?

 

[brisvr4]

Paul I think I kight have to swing past Troy's again soon to double check the centre diff from his Evo 3 box.
It's out of his car and I have at least 3 VR4 boxes there so I'll check them out. I also have a VR4 RS box in pieces atm so I can compare that one too.
Changing the front diff ( crown and pinion or output gear as it is known ) isn't an issue. We did it in Troys Evo 3 in order to make it match his 3.5 rear end.

 

[alansupra94]

Excellent! This is looking to be pretty sick.

Also I see your point about having just a taller 4th. I personally think I will like having all the gears taller. I am going to have a VGT turbo and pushing around 550hp so I think I can get the car pulling pretty fast /ubbthreads/images/graemlins/smile.gif

The reason I didn't go with just a taller 5th is that my transmission is already rebuilt by turbotrix. Would be a shame to just waste it especially considering I wouldn't get much for it. Plus this whole transaction is only costing me $90 for shipping and straight up trade for some Greddy Gauges I have.

 

[cheekychimp]

Oh I think for the roads you have over there you'll be very happy the GGSX hybrid box is ideal for cruising and if you get that VGT turbo working properly and get to harness that power at lower rpms you'll get a whole host of other advantages. The higher gearing should help with traction and in stop and go traffic with enough power it should actually be beneficial because it may eliminate the need to keep making that annoying 1st to 2nd and back to 1st again.

You are going to be able to do over 60 mph in 1st /ubbthreads/images/graemlins/ooo.gif

As for me, I still think I'm going to be okay. I've never had an opportunity to hit more than 120 mph in Hong Kong and my current transmission should do near to 130 mph in 4th at 8000 rpms and well over that at 6000 rpm in 5th whilst 1st through 4th will have closer ratios than stock and very compatible speeds in each gear. It should make for great driving around town with the extra power and torque of the 2.3 stroker.

 

[alansupra94]

Yeah but that would be with a 9k red-line. I have mine set basically at 7800rpm just for safety purposes.

I can do 230mph in 5th at 7800rpm though /ubbthreads/images/graemlins/grin.gif

 

[curtis]

^ with how much spray. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/rofl.gif 550 want do 230 in a brick car we own. Yea we both have big hopes for the VGT and I really think it will go way past 550 but thats with everything perfect and all the supporting mods. 72lbs a min should do up close 750 but Its amazing how much power is needed to go just a few mph faster even with the correct gear. I remember seeing an article in a mag about a silver state classic build up of a 93 cobra mustang. They hit like 193 and that was it at about 600hp they had to get it up over 800 to go past 200 but remember thats at 6 to 7K range with a big heavy V8 plowing the road. But we all own a aerodynamic turd and I just don't think I would want to be in it at 230. The 1g was designed on a day after mandatory vacation. Ours was designed after the company Saki party, wheres the little Japanese engineer smiley holding the shot glass upside down over his head. /ubbthreads/images/graemlins/grin.gif

As for the stuff Paul I need just the ring and pinion unless the diff is an LSD and I'd take that but I really doubt that that car got an LSD.


This is my thoughts on it. Lost of V8 cars switch to a 4.10 or 4:30 gear when they start the build then soon discover when the car is getting up in the 500 range on power there running out of gear or having to go into 5th in the quarter at about 1100 ft. This happened to my Mustang years ago. It was pulling like a monster till about 1200 ft then had to go to 5th and the tremec trans I had had a tall 5th for highway cruising and would fall off and car would runner slower than just bouncing of the rev limiter. Most guys I'd say 95% go to a taller rear tire. I did the last time I ran the car and by going up in tire size dropped over a second in the quarter then the bottle pressure when to crap.. /ubbthreads/images/graemlins/banghead.gif Easy to do but I have a set of 17's and 18's and don't plan on running 28 inch tall tires of the Galant and 15's want fit with the brakes so this is really the only option. I really have a feeling the car will be close to the shift point in 4th. Its that or rev to the moon which I have the parts for just not the rebuild time if I grenade it. Plus will be nice to drop the rpms down on the interstate. I haven't done the math but from the 3:50 range to the 3:30 range should be around 600 to 800 rpms on the tach.

 

[cheekychimp]

Yeah I think the higher gearing is about better cruising rpm, arguably better gas mileage and faster 1/4 mile times. You just aren't going to be able to exploit all that gear in a Galant. Shep might make trick tranny's but he was still using stock ratios as far as I know up until a few years ago and went what 167 mph in 4th? It isn't the gearing that's the issue it's power and aerodynamics like Curtis said. Hands up how many people have gone over 160 mph in a Galant ... I bet the land speed record Galant boys are the only ones and their car awesome though it is is hardly a road car and you can see how much work they have gone through in an effort to make 'the brick' vaguely aerodynamic!

 

Just in my test fix it seems to work. no chatter no issues. had to swap the output and the diff together and then it works great! i didint bolt the trans together and it didint have fluid but it turned smooth and doesnt seem to have any catch or snaggys... snaggys being a technical term.

 

[alansupra94]

Lol I guess I should have said I could "theoretically" do 230mph *cough* Curtis *cough*. Did you guys really think I could move this refrigerator-ly aerodynamic car to 230mph with only just 550hp? /ubbthreads/images/graemlins/rofl.gif

I don't plan on doing top speed runs or anything like that. I just plan on making it my semi-daily and highway monster just like my supra. I know that those VGT can flow like 750hp but I wouldn't be able to handle it in the setup I have now. Maybe in the future I will build a nice motor but I am happy with 500hp in the motor I have now.

At the end of the day, I just like being unique or as Steve called me "special" /ubbthreads/images/graemlins/dunno.gif