Newbie question

[Andy wright]

Latest plans for Lotus improvements. Brakes. Nothing too radical . Set of four two piece rotors from Seriously Lotus, complete with RCL5+ front pads and some Mintex 1144 at the rear. All that lot still in boxes. Next step are the front Calipers . I rebuilt the set that came with the car last winter. Nothing wrong with them except that they are an absolute pain in the bottle to bleed. Why AP decided to top feed them is beyond me , especially as the sister Calipers  CP5316 and Cp5317 which are indelicate except for piston sizes  are side fed. So, I found a spare set of front on Facebook marketplace , stripped them and converted to side feed. As soon as I have them painted they can replace the ones already on the car along with the discs. The other change is to the master cylinder. I have splashed out on a larger bore one. Any why? Because on the S2 with the Toyota power unit, the brakes are servo assisted . Any they are over - servoed with a bit too much travel . So I am hoping that a move to a MC with a 20% increase in piston area will help with both a reduction in pedal travel and an increase in pedal effort, particularly when slowing from 20 or 30mph to a stop . At the moment , it’s quite difficult to do that smoothly . 

The plan is to use a banjo fitting for the hose. Ideally I would have made the m10x1.00mm bolt hole blind and just left a  3mm hole into the cylinder but even with the very conveniently placed raised boss that just needed milling flat ,I would have been short of thread depth on the bolt. 

[LotusPanelRepair]

Which master cylinder did you choose I’m guessing the Elise parts one from the description. Will be interested in how you find it. I’ve got an AP 4 pot kit waiting to be fitted but I’m also looking to put the current 2pots on the rear hence looking at the master cylinder. 

[Andy wright]

9 hours ago, LotusPanelRepair said:

Which master cylinder did you choose I’m guessing the Elise parts one from the description. Will be interested in how you find it. I’ve got an AP 4 pot kit waiting to be fitted but I’m also looking to put the current 2pots on the rear hence looking at the master cylinder. 

Yes. That’s the one . Damned expensive but it does help future proof as I plan to go down the ‘2-pots  on the rear’ at some point ( I now have a spare set 😀). I really do think that with 4 pots up front and then a jump from 36mm to 44mm bore on the rear pedal travel will become a factor . 

[LotusPanelRepair]

2 hours ago, Andy wright said:

Yes. That’s the one . Damned expensive but it does help future proof as I plan to go down the ‘2-pots  on the rear’ at some point ( I now have a spare set 😀). I really do think that with 4 pots up front and then a jump from 36mm to 44mm bore on the rear pedal travel will become a factor . 

There is very little piston area difference between the official 4 pots and the standard 2 pots so in itself shouldn't a reason to change, but the increase in the rear and to firm up the pedal with my plan means its probably worth doing. 

[Andy wright]

2 minutes ago, LotusPanelRepair said:

There is very little piston area difference between the official 4 pots and the standard 2 pots so in itself shouldn't a reason to change, but the increase in the rear and to firm up the pedal with my plan means its probably worth doing. 

Out of curiosity , what are the piston sizes of the 4 pots that you plan to use ? And a complete aside and thread hijack. My S2 is non aircon and the heater panel , if it ever was back lit, definitely is not now . Can you offer a service to remedy this awful error/ problem ? 

[LotusPanelRepair]

I've got the standard 4 pot kit from Lotus which was fitted with no changes to the master cylinder on the Exige 240's and up. Being lazy I'm going by the numbers on google rather than measuring them so google suggests 36mm and 31.8mm pistons which is around 20% more piston area per caliper. Actually more than I thought it was.

 

To your other question aircon or no aircon the heater panel in your age of car would have lit up once upon a time and yes it is something that I can remedy for you. I'll PM you if you want rather than bog down this thread with the discussion.  

[MG4Lotus]

Thread title is Newbie question, so not sure how much of a thread hijack that would be. 😉

[DeanB]

Can I make a brake pad suggestion? I have used RC5+ on the front axle and RC6 on the rear with great success. I think the oem brake bias is a bit on the conservative side and the system benefits from higher coefficient of friction pad material on the rear.

I wonder if the 1144s might be a bit soft and weedy. 

[Dave-hp]

1 hour ago, MG4Lotus said:

Thread title is Newbie question, so not sure how much of a thread hijack that would be. 😉

30 pages and 292 replies, but mostly down to Andy completely rebuilding his Elise and still going!!!

[Andy wright]

Ah.Yes. Point taken. I was going to use the 1144 just because I have a set and they have not seen much use. However, I accept your point that with new discs all round and brand new Rc5+ at the front I ought to shape up and get some RC6 for the back.I take it that the RC6 is more track focused and has a higher coefficient of friction . 

[DeanB]

Yes, it is and does. They burn through discs a bit quicker but the stopping power is worth it.

[Andy wright]

Bit of progress this afternoon. Front calipers duly tarted up and rears about to suffer the same fate. Master cylinder removed along with the fluid reservoir . 

[Lithopsian]

Those Brembos look pretty spotless. Have they been de-rusted?  Coated with something?  Fully refurbished even?  The piston boot looks a bit dodgy in that photo though.  Or has it been painted as well?

[Andy wright]

Boots are ok but that one I moved slightly to check all was ok. They are not old Calipers. Been on the car  about a year , so a thorough  clean and they look pretty good. Now bling blue of course, to match the fronts.. 

As an aside , trying to decide whether to ‘ delete’ the ABS whilst I have  the hydraulics disrupted. Only the Toyota S2 Elise’s got the system , and getting rid of it would massively simplify the pipework and make brake bleeding easier ( and shed a bit of weight too ) I will sleep,on it .

 

[LotusPanelRepair]

ABS became a legal requirement around the time lotus switched to Toyota power. Maybe an interesting conversation with insurers on why it’s been removed. 
If you have traction control that’s managed through the engine and ecu but worth checking the route the signal takes as you may loose that as well however if your removing abs then I guess traction control is low on the priority list.