Zetec 2.0 mods & questions

[Wynand]

Im getting depressed when I see prices you guys in Britain pay for parts.
A secondhand set of bike TB's here cost the equivalent of about 450 pounds Sierra diff about 340 pounds and a Zetec 2.0 engine about 720 pounds - all secondhand prices from the scrappy.....

And since it is "mechanically" very expensive to mod an engine in SA, I have a few questions about the cheapest way to get a Zetec to produce decent HP. My engine is a Mk 3 blacktop - 2.0 liter.
Here follows my options.

1. Throttle Bodies: Throttle bodies are expensive here, and it would rather pay me to buy a complete silvertop Toyota 4AGE 20V, take off the TB and throw the engine away rather than getting bike (read expensive) TB's. Off the shelf TB's kit for a Zetec here just below a 1000 pounds!
From reading old posts, this seems the way to go to get ponies fast. But due to cost and complicity (ECU etc), this would be a last resort for me.

2. Carburetors: Since I have a pair of double choke Weber side draughts, perhaps stick to these and as a bonus, only need a simple and cheaper ignition unit. Problem with these fitted is that I may need to cut a hole in the bonnet to accommodate the carbs and this I don't like at all.

3. Stock TB: This idea appeals to me - To fabricate a decent shaped and calculated plenum and runners from ally (Im a boilermaker) and fit the standard Zetec TB and leave the injectors as is on the engine. Have a cool air intake fitted to TB.
Simple and clean and at least have a single cone air cleaner fitted to keep dust out of engine instead of that smart looking open trumpets on TB's. We have serious dust storms in my region from time to time.

With the above it goes without saying that the exhaust manifold will be a well designed tubular branch and the flywheel will be lighten considerably.

The questions now are: what is the best setup for those that been there done that and why?
What hp can one expect with each the three options?
Any other advice on this?

Finally, my reference to the Toyota 4AGE 20V - can have a blacktop for much less bucks than the Zetec, but running with a type 9 box, 3.7:1 diff and the AGE only making max hp at 7900rpm = 120kph in second!! Max torque at about 5400rpm. Would not be a nice car in traffic/town but brilliant on track.
With same rims, tires, ratio's etc the Zetec will pull 100kph at 6100rmp - right on max HP and max torque (lots of it) is at about 4000 rpm and this would be a nice car with lots of oomph in any gear.
In short, its all about torque
But strangely, the 4AGE is the engine of choice in South Africa for a seven.

[alga]

Wynand, nice boat building site you have! Hulls are such beautiful things.

Have you considered that you can use the UK ebay site to get the relatively small things like bike carbs or bike TBs? The shipping cost might be pretty high, but you should still end up better off than buying locally with those prices.

[mr henderson]

Originally Posted by Wynand

2. Carburetors: Since I have a pair of double choke Weber side draughts, perhaps stick to these and as a bonus, only need a simple and cheaper ignition unit. Problem with these fitted is that I may need to cut a hole in the bonnet to accommodate the carbs and this I don't like at all.

If you already have the carbs, and cost is an issue, then if I were you I would stop worrying about making a hole in the bonnet and get on and do it, it's going to be by far the cheapest solution, and if in the future you go for a different set up it will be easier and chepaer to get/make a new bonnet.

[snapper]

There are some very thin inlet manifolds available and short bell mouths for the carbs, you will loose bhp and torque but could stay within the bonnet.
Cutting the bonnet will give benefits, you can match the inlet tract lenght to the cam and have a continuous supply of cool air which gives more bhp

[big_wasa]

I say number three

Because I have.

Mk1 steel version. allu mk2 to come next year after iva.

http://www.youtube.com/watch?v=BKqeCjdBM0w

[ozzy1]

Plenty of guys at my car club have the 4age blacktop/silvertop and its a nice car to drive .I dont understand why you think its going to be bad around town as the standard corolla is a decent car and your putting the engine in a car half its weight.120kph in second !your not going to be doing that around town and who cares anyway as you have another 3 gears to play with.Maybe worth having a drive of one to truly appreciate this motor.Just as a note maybe look at
http://web.mac.com/rawuk/Raw/Home.html
they do supercharger kits for the 4age.

[Wynand]

Ozzy, the problem is my diff ratio with the 4AGE and the lack of torque below 5000rpm.
My town/city has no traffic lights but only traffic circles (about 40 odd) and sometimes you have to accelerate out of harms way with strangers that really do not know how to drive trough multi lane circles happens to be in town. Same apply for some ingenious locals ...

My daily runner is an Audi A4 TDI and many times I had close calls when I had to get out of harms way and the engine just making induction noise without going before the turbo get on the boil. Usually it is just flooring it to get away and a gear change would take to long and shit may happens.

With the AGE blacktop going 125kph on peak HP it translates to about 3900rpm in 2nd at 60kph - our city speed limits - and usually one goes into a traffic circle at less than that and to get out of harms way, that warrants a down shift to 1st gear!! and try to do that at 50kph

This is why I decided on a Zetec 2.0. Ratios of type 9 box and Sierra 3.7:1 ratio diff is a match made in heaven and the Zetec has a lot of torque, much lower down the scale of the 4AGE.
This can only translate to motoring bliss