Tips for X20 XEV ecotec engine (by shrink)

[Gaz]

Having owned an ecotec for quite a while, heres my list of top tips

1) make sure your using a close ratio gearbox, the SRI was the only one to come with one as standard, this makes a huge difference to the car.

2) Change the flywheel.... that 12 kilo beast on the ecotec kills acceleration and throttle response, it ruins your in gear acceleration and mucks up downshifts something spare. Take a visit to courtenay and pick up their 5.6 kilo lightened billet flywheel.

Once thats in, and mated to a close ratio gearbox, the ecotec REALLY flies, and has no trouble whatsoever keeping up with a standard XE SRI.

3) Wrap the air inlet pipes in heat rejecting foil, stop heat getting to any of the air feeds in the car, the ecotec runs like crap when its hot, so keep it cool, make sure a plentifull suply of cold air is getting in.

4) Lexmaul manifold, this replaces not only the poor manifold on the ecotec but also the 2-1 downpipe. Expect a noticeable improvement in torque, power and overall driveability, as well as a great noise and a manifold you will never need to replace.

5) Get a cat back system (but dont remove the cat) a decent cat back system will make the most of that lexmaul manifold and you can expect slightly cleaner and free-er feeling top end. Dont remove the cat though, its just not worth it. All it does is mess up your torque curve and ruin the ecotecs lovely low RPM pull.

6) Decent spark plugs and good 15w40 oil are a must. The engine responds well to good semi synthetic oil. in fact a good service with some NGK spark plugs, some good oil and a proper vauxhall air filter can make all the difference.

and 9 out of 10 times if you totally remove the cam sensor and clean it off... it usualy works fine again.

you can put the old 2.0 8v flywheel and clutch right on

but remember.. it has to be the flywheel and clutch from the 2.0 SEH engine (the 130bhp one) the later 8v flywheels were pot also.

the important thing to remember is that the flywheel and clutch have no bearing whatsoever on what gearbox you use... as long as the flywheel and clutch are matched..

on a standard XEV clutch/flywheel you could use F16, F20, F18, F28 and they would all fit just fine.

its just important to make sure that you are buying the correct clutch for your flywheel, sothat the friction plates match up.

Also remember, that the 8v flywheel is lighter at 9 kilos.. but thats only a 3 kilo saving... but... and this is a big but, the 8v clutch is heavier, meaning the weight you just saved on the flywheel is mostly made up again by a bulkier clutch.

The best solution is a properly lightened XEV flywheel so that you can use a nice light late clutch, meaning you actually save a decent amount of weight, using an 8v one wont make a huge amount of difference.

Sadly you cant use the 7 kilo XE wheel, as it has 8 bolts and the ecotec only has 6.

also remember when cleaning the idle control valve on the ecotec to make sure you clean out the associated breather hoses leading to and from the throttle body, and also clean out the throttle itself and the small breather hole leading to the ICV

if you dont do these things, you might as well not bother cleaning the ICV as the problem will come back in about a weeks time.

The flame trap mod that everyone goes on about for the ecotec is largely a waste of time, its just one more thing that gunges up, basically rather than filling your ICV full of crap, this gets full of crap, then the ICV gets full of crap, so you end up with two gunged up things rather than one.

still better to get a proper billet flywheel.. if you lighten an existing one.. you weaken its structure... now maybe its just me.. but i have a problem with weakened bits of metal flying around my engine bay at 7000rpm!!!

the proper billet one is lighter to start with, will take a proper XEV clutch and uprated one if necessary and is a straight fit.... machining an existing 8v flywheel is gonna cost a bit anyway, so why not juet start right in the first place... much easier if you ask me.

As for manifold... lexmaul all the way, its the only decent performance manifold available for the ecotec, not cheap no, but it works.

Scoprion do some lovely cat back exhaust systems for the ecotec, as do sportex so your choices are fairly wide, or you could get something custom made up.

although TBH the existing system isnt exactly restrictive, as its designed for the V6, and as a result is required to deal with much more flow than the 16v ever puts out. As a result, unless your desperate for a nice noise, i wouldnt worry about the rear part of the exhaust too much.

It made more difference to older cavs where the bore was quite small, but the ecotec shares the 2.5" bore of the V6.

[colin]

Shrink
Scorpion no longer support any of the normally-aspirated Cavalier range.
Last time I looked, they still supported the Turbo models but even that could have changed by now.

This pleased me immensely as both my cars had Scorpion Monza cat-back systems - Scorpion's copper-bottomed guarantee suddenly wasn't worth the paper it was written on.