1993 Vauxhall Cavalier SRi from UK and Ireland - Comments

Redtop:

1. Leaky cam cover gasket

2. Leaky sump gasket

3. Fan switch plug corroded (hence loss of radiator)

4. Clutch cable

5. Rail fuel lines leaked

6. Bonnet release cable.

Ecotec:

1. Leaky cam cover gasket

2. Leaky sump gasket

3. Head gasket

4. Rail fuel lines leaked

5. Bonnet release cable

6. Cam sensor failure

7. Crank sensor failure.

I currently own both an ecotec SRi and a redtop SRi.

In accurately comparing them, I have tried to establish and maintain control conditions as religiously as possible. Same tyres, brakes, shocks, springs (-40mm) along with same plugs, (even both sets of leads are BERU) fluids, be it oil, gear oil or fuel (exclusively Shell Vpower). They both have identical service intervals (done by myself) ; both have panel filter induction mods and both have comparable 4-2-1 manifolds (LexMaul in both cases) firing into sports cats and freeflow systems designed and installed by LongLife.

I drive neither with any preference as I like them both.

What I have learned is that the mods have made a noticeable difference to the redtop, whereas identical mods have made a dramatic difference to the ecotec where I would have to say the single biggest difference was made by the new exhaust system and manifold; you really need to lose the old one to realise how much it was strangling the ecotec, and once you've got it off, just how much the manifold and downpipe weigh! Both cars have identical oil cooling systems fitted.

However, I think both cars current performance is the sum of the care/maintenance/modifications and don't really want to rule anything out, simply because it only made a small contribution.

Having removed the external differences, it levels the playing field and allows the engines to be tested solely against each other, rather than either enjoying an advantage that would unfairly offset the outcome.

The redtop now surges relentlessly up to its top end whereas the ecotec's more convenient band of torque is now even fatter and it really fizzes in mid-range.

I think the redtop will still shade the ecotec off the mark, but I also think the tables would be turned in mid-range with both cars side-by-side kicking-down simultaneously from fifth and burying it, the ecotec is now THAT GOOD in mid-range.

The redtop would steal it back as you move out of the top end of mid-range, but that's more down to the lumpier cams than anything else, and I promised myself I wouldn't touch the engines themselves as this would void the test.

I hope this goes some way to answering this ever-hot debate; in standard form, the redtop is a significantly better car than the ecotec - it pulls you while the ecotec needs to be pushed. Even up the mechanical conditions for both cars and it's a different story - the ecotec will make the redtop work for everything and on a twisty road scenario, the better mid-range grunt would possibly even win it for the underdog.

It's been very absorbing, I've enjoyed every minute of it, and it was fun seeing how introducing external equalities only really highlighted the differences between the two units - I've now got two cars I love owning, they're used as my commute on a week on/week off basis.

I've yet to rolling-road either car (soon) and hope to produce some official figures for 0-60; 1/4 mile and top end (if I can find somewhere long enough and safe enough) but I don't think anyone else has gone to these lengths to compare the two 16v units in such a fair manner.

On a day-to-day basis, the ecotec is the more useable of the two, this is where the milder cams come in, making the ecotec so much more driveable in more scenarios; it's at home on the motorway, sweeping country lanes and through town in rush hour. The redtop will let you down on the last one, the lumpy cams really don't like tootling along and want to be blasting down the outside lane, fast - and that's the thing with the redtop, it only really does fast.

So, to add my two cents, which engine is better really depends on many things:- the state of tune, the mileage, the service history, mechanical condition, mods, even fuel, but if the two cars are maintained well and modded to the point where they're on a level playing field, there's nothing in it, it's really down to what the individual wants from an engine, the top-end rush of the redtop or the mid-range grunt of the ecotec.

Hope this helped, any questions, I'm on

colin@samara1.plus.com.

and will be happy to answer any questions.

I have a red top and my local mechanic says he wants the engine when I've wrecked the rest of the car.

I have no mods to this engine and agree with almost everything you say except the mid range. I find my engine to be smooth right through the rev range from pottering around town to howling it down the French motorways (122 miles in one hour)

The thing that makes the biggest difference for me is the quality of the fuel. Two or three tanks of Tesco's best green stuff and the pinking is there right through the rev range. Put some of Shells very best in and It's off like the proverbial rocket, no pinking and better mpg's in the bargain.

I love my Sri and even though it is just about to broach the 150,000 mark I hope that it will go on for at least another 100,000.

I wrote the "An excellent car, much underrated" review and stand by my comments.

I didn't think they did an Ecotec SRi, and quick question, I have got a 1994 Cav SRi and I'm not sure if it's 115 or 130 bhp. Can you help with that at all?

My SRi has done 202,000 and it still runs like a dream, not even any tappet sound coming from it. The 2.0 8v lumps are bomb proof, but run hot.

As a 94 SRi it could be one of three.

16v C20XE redtop (150bhp); one or two of these made it to 94L. Easy enough to tell, does the big, grey engine cover have a red 'letter L' running across the middle of it?

16v X20XEV ecotec (136bhp); the start of the production run for the ecotec. Again, easy enough to tell, does the big, grey engine cover have a black stripe running across the middle of it?

8v C20NE (115bhp); curiously still being manufactured in the same year as the ecotec and redtop units were coming and going respectively. Will have the narrower, grooved engine cover and a catalytic converter after the downpipe.

What it won't be:-

8v 20SEH (130bhp); outwardly physically similar to the C20NE this engine was associated with the pre-facelift versions. Production ran out in 1992 if I recall so if yours is an 8v it ain't this one.