Straight cut gears/box options

m1tch · August 24, 2011, 09:24:05 PM

Hi everyone,

Just wondering how much it would cost to get straight cut gears for my FC, might also get a ikeya shifter as well

Basically I am upgrading my power level again, so I doubt my stock FC box will cope running over 3 times stock power through it.

I have been told that the rx8 box is slightly stronger, but is there anything that I can buy to upgrade the gears etc so that they can cope? I can\'t really afford a jericho box!

Just wondering what my options would be for running higher power, I will be ok for a while though. I do know that the MX5 5th gear fits the FC box giving it a longer 5th gear for economy, are there any other OEM gearsets (like out of a Mazda truck) that might be stronger and still fit?

Grant Monkhouse · August 24, 2011, 09:48:58 PM

If your wanting any kind of box to handle power you got to pay the big bucks for it. Also if your worrying about the box you better worry about the diff too as that will go caput straight after you solve the gear box issue.

Best advice is to be sensible with what you want to build and build it reliably so you don\'t have to keep spending money on it.

Perfect example is from rs8 this weekend, James willaday runs a 6grand sequential dog box and he broke it this weekend. Not something you want to be doing is it really.

You can strengthen the gear box from twisting by removing the bottom plate and have a thick steel plate cut and drilled to go between the box and the original plate.

Hope this helps.

m1tch · August 24, 2011, 09:51:40 PM

I will be running a sump ring on the engine anyway, what usually breaks the box? Is it the twisting or the internally physically not coping lol clutch is only rated to 700bhp though.

Rzla · August 24, 2011, 09:52:17 PM

Quote from: Grant Monkhouse;784406If your wanting any kind of box to handle power you got to pay the big bucks for it. Also if your worrying about the box you better worry about the diff too as that will go caput straight after you solve the gear box issue.

Best advice is to be sensible with what you want to build and build it reliably so you don\'t have to keep spending money on it.

Perfect example is from rs8 this weekend, James willaday runs a 6grand sequential dog box and he broke it this weekend. Not something you want to be doing is it really.

You can strengthen the gear box from twisting by removing the bottom plate and have a thick steel plate cut and drilled to go between the box and the original plate.

Hope this helps.

Care to explain the bold part? Have you done this before and on what set up?

Grant Monkhouse · August 24, 2011, 10:05:16 PM

Basically a sandwich plate on the bottom of the gear box where the access panel is. A bit like a plate inserted on the bottom of the engine to stop it twisting. A number of people who\'s engine and setups iv seen have done this. I don\'t know how much difference it would make but trying twisting a 10mm thick steel plate on the bottom of the gear box takes a lot of torque!

Grant Monkhouse · August 24, 2011, 10:13:13 PM

Quote from: m1tch;784408I will be running a sump ring on the engine anyway, what usually breaks the box? Is it the twisting or the internally physically not coping lol clutch is only rated to 700bhp though.

Torque generated by the engine creates twisting motion. Think of it as a reason why people solid mount there engines to the chassis etc. It\'s becomes noisy but strength is gained.

Don\'t take my word for granted but if your planning to over power a 700HP clutch then you better be thinking of chassis strengthening. A good cage.

m1tch · August 24, 2011, 10:22:24 PM

Yeah, I am planning a full weld in cage as its a handling upgrade - best strut brace you can get! But won\'t be for a while, im just thinking about what I might need in future, my FC will never be sold, so it will be a work in progress, probably keep it around the 500-600bhp power for a while, stock FC box, stock FC diff and stock FC oil cooler are rated to that power anyway, unlike the FD drivetrain that seems to be a bit weaker!

The car will be in full street trim, will be 100% street legal and won\'t be stripped out, its not my daily drive, but its driven on the road, so I can\'t exactly get a 3 speed box lol

Would swapping out gearsets with another Mazda be an idea?

lee mills · August 24, 2011, 10:24:02 PM

What turbo you getting now?

m1tch · August 24, 2011, 10:26:36 PM

Quote from: lee mills;784427What turbo you getting now?

Buying Petes older TA45 hybrid off Keith, basically an old school T51

should make good power :chat

Ive found that PPG do a full 5 speed straight cut set for the 7

Grant Monkhouse · August 24, 2011, 10:30:54 PM

Yes but finding a Mazda box that was built for power will be very unlikely.

There\'s nothing wrong with FD boxes, it\'s just that when people use a 20b they use the fc bic because it can be made shorter to allow the engine to be moved further back. 103mm to be exact as im currently looking to mod my FD box with the read housing off an fc box and shorten it to go in my rx4.

I honestly don\'t think your diff is going to cope too well at 600whp unless you have removed it, cleaned it strengthened it and replaced all the bushes. And maybe solid bushes for the diff mounts as they are probably going to take a beating with that power

m1tch · August 24, 2011, 10:35:03 PM

Wouldn\'t all the damage occur if you suddenly shocked the drivetrain with that much power though? I would only run that power progressivly in say 3rd, 4th and 5th, 1st and second gear I would run at a lower power so I can get traction etc

Grant Monkhouse · August 24, 2011, 10:35:24 PM

Why don\'t you save a bit of cash and get a GT42, if this cars going to be a long project it will be worth the extra cash.

lee mills · August 24, 2011, 10:36:44 PM

Quote from: m1tch;784428Buying Petes older TA45 hybrid off Keith, basically an old school T51 should make good power :chat

Ive found that PPG do a full 5 speed straight cut set for the 7

according to his ad on fduk it was pointed out that it would only make 4_470bhp tops.
might be wrong but worth checking out with someone who knows more about turbos( ie Ed) before you sell your t88 as im sure you dont want to be making less power;)

m1tch · August 24, 2011, 10:39:19 PM

I think there will be many turbos attached to the engines in this car lol my initial plans were to fit a GT4088, then it was a T88, now a TA45 lol I will be at a GT60 by next year

Im still well within budget on my car, so I guess I might upgrade to a GT42, think I will get all the ancilaries sorted first though, need to add in a 3rd fuel rail and an AN8 fuel line, plus buy 2 more fuel pumps first!

m1tch · August 24, 2011, 10:41:02 PM

Quote from: lee mills;784436according to his ad on fduk it was pointed out that it would only make 4_470bhp tops.
might be wrong but worth checking out with someone who knows more about turbos( ie Ed) before you sell your t88 as im sure you dont want to be making less power;)

Yeah, some people said under 500, some say 700 lol the turbo is as big as a T51, so slightly bigger than my T88, plus its a hybrid lol trying to get hold of pete to see what numbers it made before it ate his engine!

There is a TA45 powered SA22C RX7 thats making 601 RWHP

http://www.youtube.com/watch?v=rhxTsGXJvNQ

isn\'t exactly small: