[JuggernautMotorsports]

Hello all, this is my first post here as I just registered today. A little background to start; My codriver and I have built a 2000 ZX3 rally car that we have been running it in Canadian rally for about a year and a half. The only thing we had done by someone else was the roll cage and seat mounts as safety is always first.

Lately as we have been getting faster, I have been in 4th and even 5th on stage and both of these gears lack oomph to say the least. I find that there is little to no torque in 4th and 5th is just disheartening.

What I'm asking is what you guys think the next best option would be to get a slightly more usable 4th and 5th. My budget is not large so keep that in mind and yes my plans do include a 13:1 high compression build w/ported head sometime in the future but I have a couple seasons before that.

As our class is Group 2, we are limited to 2wd, with a naturally aspirated engine below 2400cc. With the 4 valves/cylinder multiplier (1.15) we currently sit at 2300cc so a 2.3 duratec is out of the question as well if we want to stay in our current class.

Mod list:

Volant airbox with scoop
SVT header with custom 2.5" exhaust from header to the rear of the car with a high flow metal substrate cat in the tail right where a muffler would be (the rules state we need a cat in the exhaust system somewhere, so that's where it impeded airflow the least)
Fidanza light weight flywheel
Ford Racing clutch disc and pressure plate (actually clutchmasters)
Mfactory 4.75 Final Drive Ratio (Ring and Pinion)
KAAZ 1.5way clutch pack differential
Screamin Demon coil pack w/wires (plugs gapped to .065")
B&M short shifter w/custom extension rendering the shortness long again
Raptor Performance shift light set at ~6250 IIRC

Ford Racing rally brake kit w/Hawk blue pads up front, hawk HP+ in the rear w/wheel scrapers front and rear
Ford racing subframe
Hotbits DT1 suspension front and rear w/coilover setup in the rear (stronger than the DT2 from what I've been told)
Custom tubular control arms and lateral links with heim joints
3/4 inch spaced rear spindles

Fairly severe weight reduction

So basically with the FDR and diff. the car rips in gravel/snow spec but only through gears 1-3 then it gets weak.

I recently found AEM camgears and Ford Racing Stage II cams (made by Crane) on a junkyard car for cheap so I'm strongly thinking about putting those in.

I suppose I could pull the head and have it decked .040" for around 10.5:1 but how long will my engine last at that CR? Running 94 oct. is what we usually do anyways so that's not an issue. Should/could I go to 11:1 on stock pistons and rods? Also the engine has around 236,xxx on it but compression tests were matched across the cylinders and the numbers were good.

The car has never been dyno'd and some of the mods I did were to preserve the low end power and torque since torque is really what we want for rally, don't much care about HP. Almost forgot that I have considered a proper close ratio gear set but with the only offering coming from Quaife and running around $3000 it's a little too far out of the budget for now.

Hoping you guys have some great options for me!

Some gratuitous action/car shots for you guys:

Our wind tunnel testing on the newer spoiler:

And a scandalous pic of our rear end

 

[hEaT]

Welcome! Awesome build.

Seems like you are lacking high rpm power which is where the Zetec sucks. Cams will help, as will a better intake manifold and a tune. Without those, I'm imaging the car is just falling on its face past 5,500?

 

[G-forces]

It looks like you're having allot of fun! :rock: I love the overturned picture with you both on top (because you're not going fast enough if you never wreck, and coming out safe is the best :thumbup.

As for the torque... you've already covered the best part of it with the FR stage 2 cams and gears for tuning. The early 2000 IM is better for making torque than the usual one. Port the TB for better flow. I wouldn't go even to 10.5 on stock rods the way you want to drive it, especially at its age. But a littler bump would probably not hurt, more like 10 (hardly worth it though). There are some really slick looking asymmetric 11.0:1 pistons on here, those and some stonger rods and a head shave to get 12 or more would help allot. Have you thought about Microniting your gears to allow more power to reach the ground?

Not sure what the rules allow, but once you get to the 13:1 racing compression you want, you'll also want a bigger MAF housing, TB tube, TB and injectors, and an IM better than the e2K to feed the need.

 

[sohking]

you may want to grab a junkyard motor with low mileage and start building on that before bumping compression, but this car is great!

 

[BigRed03]

See what your class rules allow for IM and cams. The FR2s will make more power up top, but may lower the tq and power below what you want/need in the lower rpms.

Several options are available for IMs, even more so from across the pond (Monotune, etc). I'd talk to Top Speed, they have street and race IM's, both do drop low end tq, but the top end gains are very nice.

Building a second block on the side like sohking suggests would be wise.

 

[Indecision]

Your car is awesome, eh!

http://forums.focaljet.com/top-speed-performance/638077-new-product-zetec-intake-manifold.html

I would look in to a Top Speed IM to help with the torque.

 

[G-forces]

It's for sure that Top Speed guys know how to build for power, but the e2K IM has long runners that allow for low end torque and it flows better than the usual stocker... while the exquisite Top Speed IM (or Dominic's IM, for that matter) will help you make peak power much better, they don't do so much at the low end.

 

[Ja-Red]

If he builds the motor for mor peak power he can run the rpms out further which would allow him not to get into the overdriven 5th gear. being able to turn the motor out further would effectively lengthen his gears so hopefully he would not have to shift as often. if he were making power all the way out to 7500rpm he would have 1300rpm more powerband. Im sure he rarely drops the revs down past 4k anyway making the "low end" not as big of a concern.

I would also not hesitate to run 11:1 compression with the stock pistons and rods especially with 94 octane. I say deck the head, run a crower stage 2 or comp stage 3 camshafts and an aftermarket Intake Manifold.

 

[hEaT]

I agree with Jared on this. This car doesn't need low-end power. With a 4.75 final drive, it need the most up top it can get. A short runner intake is what would really bring it alive where the car is spending most of its time.

 

[Ja-Red]

I dont know why focus guys get so hung up on torque?

This...

Is way better than this...

Less torque more HP and a flatter powerband.

 

[FordFociSHO]

#1
Turbo dyno #'s have no place in a discussion about N/A builds

#2
More TQ is always more HP. It's simple math. Obviously if you extend the RPM's the HP will increase :screwy:.




To the OP,

More top end TQ is what you need (duh). As stated, a shorter intake manifold runner will help some, but really it won't help much until you get into much higher power outputs. As it sits now the velocity in the intake is largely determined by the cams, which means even doing manifold swaps won't net you much.
Once you move to more aggressive cams, and the velocities start peaking more, then manifold tuning comes into play much much more.

So, step 1 is cams (and adjustable cam gears).

As of right now you're probably around the mid 130whp mark. Good set of cams on an unported head can get you close to 150whp with some aggressive timing and good fuel. That alone makes the car feel completely different.

But my opinion stands as the zetec head is just junk and not worth fussing with in N/A form. I'm running the SVT head and putting a little over 170hp to the wheels. 4th and 5th feel pretty strong in my car, even with the ****ty stock gearing.

 

[K STYLEZ]

Good condition low mile Zetec motors are $250 all day long. Grab one of them, no reason to put expensive parts on that could be harmed should that motor let go.

Get the Massive head, Crower 2 cams (maintains low end power for rally usage) and a good intake manifold. Top Speed has a nice one, or find an old FC.


Have us take at least .050" off, .080 with our custom idler. 94 should be OK, or run race gas.

If the good head and a new motor is not in the budget, shave the stock head .080, get our idler put in those cams you scored, but you NEED a good intake mani to make use of them. All the cam in the world wont matter as the stock IM puts a straglehold on any power past 6000.

Bitchin car!!! Love it!

 

[Indecision]

If he builds the motor for mor peak power he can run the rpms out further which would allow him not to get into the overdriven 5th gear. being able to turn the motor out further would effectively lengthen his gears so hopefully he would not have to shift as often. if he were making power all the way out to 7500rpm he would have 1300rpm more powerband. Im sure he rarely drops the revs down past 4k anyway making the "low end" not as big of a concern.

This is exactly why I recommended the Top Speed IM... race cars don't spend much time in the lower revs.

 

[Ja-Red]

it was just to show that a small loss of peak torque can make for a big HP gain on the top end. The same would be true for an NA motor running 140ftlbs out to 7.5k rpm which would bake 200whp.

 

[G-forces]

It sounds like your saying just raise the rpm limit and you'll get more power, but I know that can't be what you mean, lol, since we both know you can't just add rpms and expect the power to keep increasing.

The changes you make to the intake/head/cams/exhaust/tune are what make it so the engine can keep making power past its current peaks. And it's those changes that cause the trade off between loosing low end torque and increasing high end HP. You can increase the total torque only by either pushing its peak higher up the rpm scale, or by reducing parasitic losses (or both, of course).

The OP asked how to increase low end torque... maybe many of us think that's not what he really should be trying to do (IMO that's another discussion), but he's not going to get that if he mods for high end power with his current CR/engine configuration.

[apologies to OP for talking around him]

 

[hogdog]

#1
Turbo dyno #'s have no place in a discussion about N/A builds

#2
More TQ is always more HP. It's simple math. Obviously if you extend the RPM's the HP will increase :screwy:.

To the OP,

More top end TQ is what you need (duh). As stated, a shorter intake manifold runner will help some, but really it won't help much until you get into much higher power outputs. As it sits now the velocity in the intake is largely determined by the cams, which means even doing manifold swaps won't net you much.
Once you move to more aggressive cams, and the velocities start peaking more, then manifold tuning comes into play much much more.

1 - Why are you always so rude?

2 - More torque does not necessarily mean more HP unless that increased torque is delivered at the same or higher RPM's.

3 - Extending the RPM's will not increase power at all as the Zetec runs out of steam at around 6000RPM and so is pointless unless you have cams (and supporting mods) that operate in that range.

4 - Assuming Ford know how to calculate correct runner lengths a shorter intake manifold won't help unless it's tuned to operate in the same RPM rev range as the rest of the mods, if it's not it will hurt power.

5 - I think you probably do understand the subject pretty well but it would probably help if you used a bit more attention to detail in what you're typing, alot of what you've written above either makes no sense or is just plain wrong. The fact that you're unnecessarily rude with it isn't exactly going to make people listen to what you're saying either.

 

[The_Underclassman]

If you're looking to do this on a budget, I would recommend an SVT cylinder head swap w/intake manifold and to figure out repinning the SVT ECU into your car. All can be had for around $600.. small bump in compression, aggressive cams, and a dual stage intake for high rpm giddy up!

 

[JuggernautMotorsports]

Thanks to everyone for posting so far and for the warm welcome to FocalJet. I've been putting off joining for some time due to lack of time and finally found some technical Focus specific questions that I couldn't get satisfactory answers for elsewhere. I also forgot to mention that I come from a Subaru background where we swap a turbo for something used and cheap, bump the boost, throw an exhaust on, tune it and end up with another 100whp, so proper NA tuning is a little new though I do understand all of the basics and especially that flow rate and style I'll call it, matters more than just jamming air in.

Anyways so from all of this I can see that an SVT head with the FR II cams and cam gears I have plus the Topspeed IM is probably the best budget option and should net me around 170whp.

I don't have the money this season to throw at the engine or head in terms of a large port head and really aggressive cams, pistons, rods etc. Otherwise I would probably grab a close ratio gearset. So for now I'll look to find an SVT head and lower manifold plus the Topseed IM (Would you guys recommend the short runner manifold for me? Looking at the graphs I think it will be the best fit). Would I need to have this tuned other than with cam gears or can I get away with the stock computer? I've been looking at the SCT software which lets you actually tune everything yourself. Of course I would give it to a tuner to do anyways but is that the best option? I know some guys use SDS for engine management. I'm liking OMEX for standalone later but as always funds are an issue this season.

And by the way, I wasn't asking how to increase low end torque, I suppose I really knew the answer to my question and that's simply that I don't have the power, so 4th and 5th where the ratios are unfavourable is where that really hurt, while the flywheel and 4.75 FDR made up for the lack of power in gears 1-3.

Also what would my compression be with an SVT head on a stock Zetec block?

Forgot to ask if I can use the SCT software standalone with a cable or if I NEED the flasher unit/chip?

And what are the SVT cams like? Should I use those in place of my FR II cams?

 

[Ja-Red]

You cant just put an svt head on a non svt car. The svt has variable cam timing, which you either have to run the svt computer so you can control it or you have to delete it mechanicaly and lock it out.

The standard head will be fine. There are plenty of them making 200whp in europe, the US focus guys just cant seem to get the right combination. You just need someone who knows what they are doing to port it.

 

[JuggernautMotorsports]

Alright for the time being then the option you would recommend is what you posted above? That being decking the head to 11:1, throwing in the FR II's that I have (because I have them and don't want to spend on this again right now) cam gears and a Topspeed IM?