4G93T Flywheel bolts compared to 4G63T

[aapje]

I'm in the process of running a lightweight evo flywheel in my 4G93T powered Colt.

Now I'm using a Eclipse GS-T gearbox that works okay. I got a Fidanza aluminum flywheel I want to use. I got a adapter on the way to fit the spacing on the back.

Everything fits, just 1 problem. The flywheel bolts. I got a set with the flywheel, they are longer then stock bolts (this is required because the bolt flange area on the Fidanza is thicker. But when I compared the bolts that came off the flywheel I noticed they are different in size

 

[EVO-00X]

Ive never heard if an adapter plate that changes 4g93t flywheel pattern to evo pattern. You sure its going to be safe spinning the flywheel without breaking bolts and having it fly into the firewall taking your legs off in the process?

6-bolt flywheel and 7-bolt flywheel bolts are different.
7-bolt uses 12 x 21.2mm bolt. Part number MD302074.
6-bolt uses 12 x 22.5mm bolt. Part number MD040557.
4g93t GSR awd flywheel uses 11 x 28.5mm bolts. Part number MD179365

 

[EVO-00X]

Get as much length of bolt into the crank to hold the flywheel on as physically possible - VERY IMPORTANT.

Im pretty sure you'll find some M11 x 32mm and M11 x 35mm flywheel bolts from other vehicle manufacturers if you look around.

ARP sell these also:
32mm = http://www.jegs.com/...roductId=744956
35mm = ???
38mm = http://www.jegs.com/...roductId=744956

I cant guarantee they will work as Ive never had to do what you're doing, but its worth a try.

 

[4piknup]

the 7bolt evo and gsr wheels are the same, except for the locating dowel is on a different radius. i think the arp bolts have a shank that is pretty tight on the wheel holes, this may make up for grinding/pulling the dowel out.
personally, i would be using the longest bolts and trimming them to maximum thread engagement. and drilling for a dowel as well, maybe 2 dowells while im there with the drill

though evo00x mentions a size difference from 11 -12mm. i would be using 12mm and either reaming flywheel holes larger to suit, os drilling/tapping back of flywheel to suit bigger bolts. but his 2 links are different bolt thread pitches, the toyota ones are 1.25 pitch and chebby ones are 1.5 pitch. mitsi are finer than the chebby ones, and i think the toyota ones are the correct pitch. (check yours before ordering)

though you could get a die and recut the threads on the bolts from 12 down to 11mm. then the shanks will fit the wheel and the threads will fit the crank
http://www.ebay.com.au/itm/11mm-x-1-25-Metric-Right-hand-Die-M11-x-1-25mm-Pitch-/270861738507?pt=LH_DefaultDomain_15&hash=item3f109e220b
you might need to file/grind the threads down on the 12mm bolt to get the die to start. use a drill and file or grinder if you dont have a lathe.

back to drilling the crank. buy a 10.8mm drill and a 12x1.25 tap(after checking of course). drill and tap to suit...

 

[vk2kyg]

Good luck trying to re cut the threads. Flywheel bolts are high tensile grade 12 bolts you will never cut a nice thread on a grade 12 bolt with a normal die.It would be easier to recess all the flywheel bolt holes to suit the gsr crank bolts. You may also need some spacer sleeves to go over the gsr bolt and fit tight into the 12mm holes in the flywheel to keep the bolts in the center. Or as you have found out, Evo flywheels don't fit GSR engines.
Good luck with your adapter plate.
Regards Neil

 

[EVO-00X]

Jack, you dont fcuk around with the crank thread or the flywheel bolt threads man. Its highly dangerous stuff if it lets go.

 

[aapje]

Ive never heard if an adapter plate that changes 4g93t flywheel pattern to evo pattern. You sure its going to be safe spinning the flywheel without breaking bolts and having it fly into the firewall taking your legs off in the process?

6-bolt flywheel and 7-bolt flywheel bolts are different.
7-bolt uses 12 x 21.2mm bolt. Part number MD302074.
6-bolt uses 12 x 22.5mm bolt. Part number MD040557.
4g93t GSR awd flywheel uses 11 x 28.5mm bolts. Part number MD179365

I measured the 4G93T flywheel bolts they are M11X1.0 . That's an impossible to find size. ARP makes them for Ford 2.0L Zetec engines, but they are even shorter then the stock GSR bolts. The only problem a 2ltr flywheel doesn't fit the 4G93T crank is a recess. I got a adapter plate for that, so physically I can fit the flywheel to my engine now.

It's a proven concept in Malaysia, there are at least 5 people driving them. But they don't use the Fidanza wheel I'm using and there is my main problem. The bolts. I also know the bolt holes will need spacers (rather small though) to stop the bolts from moving around to much. (although they also got moving space in the stock application).

I don't feel to happy with retapping my crankshaft. Somehow I have to find grade 11 bolts or higher that are M11x1.0 and longer then the stock bolts. Beside the bolt thing I'm ready to go.

I would also rather not adjust the 12mm bolts. I don't even think there would be enough meat to start with. Maybe even bigger bolts can be trimmed down to M11 bolts. But like said above these aren't just normal bolts I don't think a normal tap and die set will pull through.

Ofcourse I'm not to fancy on the idea of the flywheel disengaging from the gearbox housing and breaching throuhg the firewall. I will choose the safest way possible, but this thing is going to work somehow because it's to cool not to work

 

[khubner1]

what about finding bolts that are longer and grinding or cutting them to length

 

[EVO-00X]

Here's a question.... why even fit an EVO flywheel on the 4G93T engine anyway?

 

[aapje]

It turns out my flywheel bolts will have to be about 35mm long. That includes some extra thread since the thread inside the crank is deep enough.

what about finding bolts that are longer and grinding or cutting them to length

If you could find bolts that are longer be me guest

Here's a question.... why even fit an EVO flywheel on the 4G93T engine anyway?

First of all I had to remove the gearbox due to clutch problems so I thought I might as well get a ligther flywheel. Since there are no flywheel options for a 4G93T I opted for an 4G63T flywheel. The only other possibility would be to get a uprated gti flywheel. But with that small size I would need a sinterplate or something and I don't like a complete on/off switch clutch.

Most importantly because it's cool I want to get a lot of potential out of a weird combination of parts. It's a CA0 Colt GTi with a Libero GT engine and a Eclipse GS-T gearbox. It's a frankstein package. After years I know I should have used a evo engine to begin with but the 1.8 has some advantages, and I like it.

I tried tapping some other thread on the M12 evo flywheels bolts just to see how hard the material is. Well let me tell you it's harder then my cheapas tap and die set There is some material coming off but it's impossible to work with.

 

[4piknup]

Good on you for trying to cut the thread. There will be enough meat left to cut new threads. Google a tapping chart and you will see. Maybe a lathe would cut the threads.
But the collars will be the go.
I thought someone I knew was using arp flywheel bolts from a Toyota, but they maybe m12x1.
Good luck and keep us posted

 

[4piknup]

I think the fly wheel turns the other way, so it will fly through the radiator not the firewall. If that is any consolation.
And it will be bloody noisy before it falls off too...

 

[aapje]

I'm pretty sure whatever solution I will end up with the flywheel won't be going anywhere Next week I will contact some metal related workshops. The problem I think is that they can't work with raw hardend material. I think bolts like these are made and hardened afterwards through some heat treatment and god knows what. This is not something a regular shop can do, and if they could I'm sure it will cost me more then a few bolts are worth.

But I'll be creative and think of something

 

[aapje]

They fit wonderfully

 

[4piknup]

What did you end up using?

 

[aapje]

I had them custom made.

 

[Qik-1.8]

What material did u make the bolts out of? 2120, 4140 I hope 4140 as its a very hard material and will take alot of force to break

 

[aapje]

Just as a update, it works

So it is indeed possible to get a evo flywheel on a 4G93T. I do notice some difference, but the end result is not as drastic as I thought. It idles the same, does climb in rpm a little faster. The only down side I noticed is the clutch has some juddering when engaging.

Still need more clearance on the starter motor cause it squeals like a pig. And sometimes not crank at all. Which is explainable because the total diameter of the flywheel is larger then the stock unit.