The Lotus Cars Community banner

1 - 20 of 38 Posts

·
Premium Member
Joined
·
4,101 Posts
Discussion Starter #1
Getting ready to install an MWR fuel rail with AEM regulator and DeatschWorks injectors. Will need to complete the wonderful task of removing the fuel pump.

Any tips or tricks for completing the joyful project on an 07 Exige with rail?

Also will need to drill a return port and remove the OEM regulator. Anyone have pictures of this being completed? Didn't turn up anything searching.

Thanks.
 

·
Registered
Joined
·
118 Posts
There are two ways to go about it pulling the fuel pump.

You could remove the fuel tank from the car (I have some photos of that in my "new fuel tank install" thread.)

Or, you can cut the access hole behind the drivers seat a bit bigger and pull it out with the tank still in place....
 

·
6.94915254 lbs/hp
Joined
·
1,770 Posts
Do you have the factory harness bar? If you do it might be easier to drop the tank. Removing the bar took 2-3hrs, and reinstalling it took about the same. Everything is blind, and there is basically no room to work...
Otherwise the job is pretty straight forward! Just do a search and you should see some pretty good write ups.
 

·
Addict
2007 Lotus Exige S
Joined
·
1,422 Posts
The return could be installed the same way it is for surge tanks, into the filler neck.

I have not done this project yet, but pics of how it goes please. I have used Earls AN bulkheads (think thats what they are called) on other fuel tanks and they worked ok for return lines.
 

·
Premium Member
Joined
·
4,101 Posts
Discussion Starter #5 (Edited)
Me......Was just reading that on your thread.....
Lost.......saw that on the BOE surge tank instructions. I'm curious if anyone else has done that.

Just ordered a fuel pump........might as well do it while I'm in there.

Does anyone have the Toyota part number for the lower/filter portion of the pump assy?
 

·
Premium Member
Joined
·
4,101 Posts
Discussion Starter #8
Thanks JJ!
 

·
Premium Member
Joined
·
4,101 Posts
Discussion Starter #10 (Edited)
No, with an AEM regulator you put a bulkhead fitting in the assy for return and remove the OEM regulator. May as well put a higher cap. fuel pump in while I'm in there. And change the sock.
 

·
Banned
Joined
·
3,229 Posts

·
Premium Member
Joined
·
4,101 Posts
Discussion Starter #12
That's a good point! Okay, I can wire it in with a relay and use Phil's schematic.
 

·
Premium Member
Joined
·
4,101 Posts
Discussion Starter #13
From what I hear or have read, if you don't rewire it, will make a lot of noise from not enough juice.

Anyone have a wiring diagram Phil's is more set up for a surge tank but I don't see why it should be any different.

Using an AEM 550 pump from MWR if I didn't mention it.
 

·
Banned
Joined
·
3,229 Posts
...and remove the OEM regulator...
Are you referring to the OEM fuel pulse damper in the middle of the fuel rail? So that means that you are replacing the fuel rail also? I'm guessing MWR's because the Radium rail has provisions for that damper...
 

·
Premium Member
Joined
·
4,101 Posts
Discussion Starter #17
Yes, went with the MWR rail,550 injectors and the non E85 pump. Not the pulse dampner, the stock pump assy actually has a small regulator in it that AEM says needs to be removed.
 

·
Vendor
Joined
·
6,306 Posts
GP, help me with the thought process here?

When I read a thread like this, it leaves me scratching my head. It looks like you're fixing parts that are not broke and replacing them with parts that are going to create a tuning problem for you.

1) AEM 550 pump? Why on earth when the Wally 255 is more than adequate? If you're concerned with the wine of the pump, run the insulator around the pump. That's what we do in the surge tanks. Quiets them right down.

2) The AEM 550 is going to create a pressure curve that "shelf" tunes do not exist for

3) A return system. OK- if starting from scratch, a return system is preferred with a 1:1 regulator. BUT when running an Exige S platform where the "recipe" is already mapped out, you adding complication that again, no "shelf" tune exists for the fuel curve

4) You cannot max out the stock fuel system with an "S" type blower system with a wally 255 and 550 injectors, so again, why the AEM pump and why the return system.... and why the fuel rail?

5) DW injectors. They're off the shelf denso 550s. That's fine, but again. Fuel people use them and I don't for "shelf" tunes like the torque300. So injector latency and actual flow rate differs from the much more common (in Lotus Land) and much less expensive Bosch EV14s like we use. So now again, the fuel map isn't designed for the DW 550s.

6) Yes, the stock regulator is in the pump housing. It should not just be removed, but blocked off to run the return system correctly. Still, a lot of extra plumbing and I'm not why. Makes sense to have the plumbing on a surge tank as it's required or if running a lot of boost high horsepower... but on an m62 with the stock tank pick-up??? You cannot run high horsepower through the stock tank pick-up anyway, FYI. It's IMPOSSIBLE to get enough gas through it to push past 320whp or so without running uncomfortably lean...

7) on 06+ cars the pump comes out of the top pretty easy. minor trimming only... An additional relay or more robust wiring is not required for the wally 255...

Sorry if this reads harsh (not intended to be), but I'm just not following why would you would go off willy-nilly modifying parts of the fuel system (that really don't need it) with these looming issues out there??? In other words, why reinvent the wheel? Not only are the parts more expensive but the solution to tune it will be as well... Perhaps this is your contribution to the "economic stimulus plan" ;)

-Phil
 

·
Premium Member
Joined
·
4,101 Posts
Discussion Starter #19
Not taken wrong Phil! Not at all, I'm the one that's on the learning curve here.
 

·
Vendor
Joined
·
6,306 Posts
GP- Read here : Exige Power recipe

Good info there with and without the self promotion...

-Phil
 
1 - 20 of 38 Posts
Top