Power flat spot

The Oily Bits S2 Specific Topics
1

Hopefully someone has had similar problems.

Graph is from a standard 240pp exige showing power at the wheels.

I’ve got a flat spot in the rev range around 7500 rmp. There’s no mil light or errors showing :frowning:
When on the dyno boast pressure was ok at around 8 psi & fuel pressure ok too. Intake temps where reasonable & timing also reasonable.

Is it a vvti problem ? any pointer?

Thanks for any help in advance.


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2

The Cam change on the sc cars is about 4500 rpm, so unlikely to be that. Can’t help otherwise, but if you get the chance (or funds) go for the 260 upgrade. It is epic :sunglasses:

3

Unable to help but another vote for 260 upgrade, Oakmere in Northwich did mine for just under 1k

4

Thanks for the replies, hopefully it’s something & nothing.

Will look into the 260 upgrade once sorted. Oakmere are only 1/2 an hour away.

Just waiting on a call back from Phoenix, if no joy will go to Oakmere

84Sprint 1k for the upgrade is a bargain, was this on a 240 car?
Is it fuel pump & ECU?

5

Could it not just be that the ECU detects some knock and retard ignition a bit?

6

Hi Wennbon,

Thanks for the reply.

When on the rollers boaster, fuel , intake temps & timing, monitored & all were within reasonable perameters.

I’ve spoken with Ollie at Phoenix, he thinks maybe the cat has collapsed or there is some restriction in the exhaust.

Fingers crossed, will find out next week.

7

Sounds like you are starting out on the $$$$ journey. Congratulations and enjoy the ride.

8

Yeah, it can get expensive quickly.

I’m hoping it’s the cat or zorst, then I can go down the 2tubular route :slight_smile:

9

Dean, 240 car and just needed an ecu reflash from lotus and bigger fuel pump

10

Thanks will look into this :thumbup:

11

Ok, time for you to plan ahead and not do work twice.
New fuel pump, yes
Reflash, maybe, it will get you to 270ish. That my be where you want to stop.After that it gets expense.
If it’s a standard 240( not PP) I’m not sure if they had the 440 injectors, you will need those minimum, may as well fit 550’s
Or get the cheque book out.
Save up and get an aftermarket ECU plus dyno £2k
new exhaust £1.2-2k
Charge cooler (can’t recall, had zeros on the end)
Smaller pulley - £90 :slight_smile:
New gearbox £2.5k ( and cooler)
Broad smile ( free)

Baffled sump, brake and suspension upgrades etc

12

Cheers Graeme

Car is a 240 pp so injectors should be good to go upto 260, with new hi flow fuel pump. Don’t think I would go beyond that.

It’s been suggested that some restriction in the cat or exhaust can cause this power loss.
Also my car is an early 240pp and may have an early map program further adding to the issue.

I’m running ALS3M0276F according to my reader, but can’t find much on this.

Plan is to replace cat & check with lotus on any updates ecu wise.
I’ve looked up into the cat using a small camera & cant see anything a drift.

13

The original exhaust may restrict slightly at higher power but for a 260 reflash from Lotus ( which should give about 270) I doubt it’s worth changing. It weighs a ton but it is quiet for track days.
The main problem is power loss from heat sink and money on a charge cooler may be money better spent.
You are probably sensible to stop at 270 as it gets Pricey beyond, but you may not be immune from gearbox woes.