The article is actually based on tuning the Ford Fiesta Zetec S but the article below is an extract of the engine tuning part of this guide.
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Zetec Tuning Guide – Zetec S/Zetec SE
As standard the 1.6-litre, 16-valve Zetec S only pushes out 104 bhp, which isn’t exactly going to set the world alight, but it will still rev harder and faster than CVH motors.
So, what are the tuning options available? You really only have two ways to go: tune the existing 1600 the naturally-aspirated route; or drop in another engine.
There is some confusion as to whether you can just bolt a turbo onto the Zetec S. It can be done but the problem is they don’t take that kindly to turbos. The standard compression ratio of the ZS motor is 11:1, so high boost is out of the question, unless you have an engine specifically built to take a turbo
Zetec Tuning Guide – Zetec S/Zetec SE
Van Aaken used to do the conversion on a DIY basis but recently discontinued it. So, you’ll either have to chat to specialists such as Interpro (01454 412777) or Performance Turbo Systems (01582 731733) and have a custom turbocharged engine built from scratch, but be warned, it won’t be cheap. Other than that, it’s N/A all the way.
If you do choose to tune the naturally-aspirated way, which we suspect you will, the first thing you’ll need to do is get the engine breathing better. An induction kit costing £85 from Pumabuild and a Milltek Race exhaust system at £239 from Pumaspeed will take care of this, and give around a further 10 bhp.
Next up, a tubular four-branch manifold and an ECU tweak are required, which should see power figures increase by 15-20 bhp over standard. Pumaspeed is now supplying a brand new four-branch Evo manifold, which vastly improves upon the older-style ones, yet still costs the same at £239.
There are a number of ways to tweak the ECU, but the most common is to install an uprated chip. Collins Performance can sort this for you at just £176. If you want to go the whole hog you can get a bespoke ECU from BPJ Services for £700, which will take an otherwise standard car up to 123 bhp. Expect to see slightly more if you have already made the exhaust and induction mods.
Now you’re getting into the realms of serious modifications and the hole in your pocket will deepen. To reach 134 bhp, BPJ Services can supply you with some 43 mm throttle bodies, which will allow the engine to rev 700 rpm harder and will run with the standard injectors. These will make your Zetec S more than a match for any standard RST, but will set you back £1490.
The next thing on the agenda in Zetec tuning is to bolt in a set of cams. Pumabuild uses a mild set of Piper cams in its Stage 3 engines, which still allows the car to idle at 850 rpm, but tweaking with the map in the ECU raises the rev limiter from 6500 rpm to 7250 rpm. BPJ Services offers two stages of camshaft, the first will see you with 150 bhp when coupled with the throttle bodies, and the second offers 165 bhp with throttle bodies, but headwork is required due to the increased lift of the cam.
There are a number of companies who will be able to sort your head out for you, including Cylinder Head Developments or Specialised Engines. BPJ Services can take care of it too, and will port the head for £550 giving around the 175 bhp mark. The firm will also supply a big-valve head allowing you to get 185 bhp out of your 1.6 for £975.
Pumabuild offers a similar engine without the throttle bodies, producing somewhere in the region of 140 bhp for £2300, but if you want mental power it also offers 200-plus bhp engines. This includes over-boring the block, making it a little shy of 1700cc, bolting in a set of steel rods with ROSS Racing pistons, a big-valve head, bigger cams, custom inlet manifold, Jenvey 45 mm throttle bodies and an OMEX management system. Prices will vary depending on the stage of tune you want.
Link to the website of Performance Ford Magazine and here is a link to the complete Zetec S/SE tuning article. The article is actually based on tuning the Ford Fiesta Zetec S but the article below is an extract of the engine tuning part of this guide.
This Fiesta Turbo article also covers the 1.8 and 2 litre Zetec engines
OC Motorsport specialise in Zetec tuning including the Zetec SE found in the Fiesta and Focus
Shawspeed are another Zetec tuning (1.6) specialist offering throttle body conversions (that avoid the alternator) as well as power packs/tuning packs and ECU upgrades and piggyback ECUs from OMEX
Ford Zetec S/SE Engine tuning guide taken from an article originally published by performance Ford Magazine. Here is a link to the website of Performance Ford Magazine and here is a link to the complete Zetec S/SE tuning article.