500+bhp Mk3 Fiesta Project

[Murdoc]

Fantasic work, the paint looks great. Did you paint it yourself if so how did you learn?

[mwstewart]

Thanks all for the kind words!

The suspension turrets are placed after careful measurement from a number of datum points taken on structural areas of the shell. I’m replacing the turrets to accommodate different top mounts: the Mk3 top mounts are an awful design and deflect/permit a lot of geometry change. The Puma/Mk5 Fiesta mounts I’m putting in their place are actually very good, and give a good compromise between NVH and handling (which is now the overall goal for this build). I know it’s only an old Fiesta, but they can be made to handle very well

I taught myself to spray and this is the first car I’ve ever painted. It will also be the last, as the sheer amount of effort required for prep, and the mess involved isn’t worth it.

[mwstewart]

I've now cleaned up the posts and fixed the broken images.

[Or888t]

mwstewart said:

I've now cleaned up the posts and fixed the broken images.

Thanks, i notised the fixed images then scrolling though, all the best ones aswell
engine brakes etc.
Looking forward to more updates good luck!

P.s do you know how much it is going to weigh once finished?
Is it going to have back seats? Surly it will need some form of a cage at 500 bhp?

Are we going to be talking 400bhp+/ton?!

[sc4589]

Why the Mk3.5?

Personally, it's my favourite Fiesta. So I understand. But what are your reasons?

I always wanted an Si. This will be epic when it's done. Are you going to keep it looking like a factory car with a useable interior and such?

[mwstewart]

Or888t said:

Thanks, i notised the fixed images then scrolling though, all the best ones aswell
engine brakes etc.
Looking forward to more updates good luck!

P.s do you know how much it is going to weigh once finished?
Is it going to have back seats? Surly it will need some form of a cage at 500 bhp?

Are we going to be talking 400bhp+/ton?!

Cheers Kerb weight for the standard Si is 963kg, however I'm adding a (large) Turbo, intercooler, a/c, leather seats and there will be a front subframe made from CDS. I expect final weight will be in the reigon of 1050kg. I've given 500bhp as a target, but knowing the engine builder, this will be more likely 520-550bhp. I found a link to a performance calculator:

Power at Flywheel (BHP) : 525
Weight without Driver (KG) : 1050
Power to Weight Ratio (BHP Per Ton) : 508.03
0 - 60 (Secs) : 4.01
0 - 100 (Secs) : 7.81
60 - 100 (Secs) : 3.80
Quarter Mile (Secs) : 12.08
Terminal Speed (MPH) : 124.36
Drag Strip Quarter Mile (Secs) : 11.88
Drag Strip Terminal Speed (MPH) : 126.63

The 1/4 mile related stuff can be ignored because its not going to be set up for that, but in-gear times should be reasonable. I'm in the process of building another custom gearbox with theoretical vmax of 218 at 8000rpm, so I at least hope to nudge 190 (current official best in the Mk3 is 184.4 at Bruntingthorpe).

A cage isn't needed from a structural integrity point of view, although I suppose it would have been sensible to put one in from a safety perspective. I want to keep it looking as unassuming as possible.

Edited by mwstewart on Saturday 12th March 12:13

[mwstewart]

sc4589 said:

Why the Mk3.5?

Personally, it's my favourite Fiesta. So I understand. But what are your reasons?

I always wanted an Si. This will be epic when it's done. Are you going to keep it looking like a factory car with a useable interior and such?

It's my favorite to date: it's the right size, it has the reinforced shell that was the basis for the Puma, and the Mk3 was also my first car. I acknowledge that 'out of the box' they are pretty far from good, but the shell has great potential.

The interior is currently at a trimmers - alcantara headlining and pillars, tan leather recaros and rear seats. I'm adding A/C and heated seats etc. so it will be very much a usable car

[sc4589]

mwstewart said:

It's my favorite to date: it's the right size, it has the reinforced shell that was the basis for the Puma, and the Mk3 was also my first car. I acknowledge that 'out of the box' they are pretty far from good, but the shell has great potential.

The interior is currently at a trimmers - alcantara headlining and pillars, tan leather recaros and rear seats. I'm adding A/C and heated seats etc. so it will be very much a usable car

Huge respect! I love that kind of project. Currently planning my own one which, granted, won't be as quick or probably as well specced, but I like it when cars are made into just overall user friendly projects. For the sake of a couple of hundred kgs, I'd rather have creature comforts AND massive performance...

Keep it up. This'll look really good when it's done. Have you considered maybe standard Ford alloys from a different model? Make it look like a secret factory model.

[anonymous-user]

mwstewart said:

Cheers Kerb weight for the standard Si is 963kg, however I'm adding a (large) Turbo, intercooler, a/c, leather seats and there will be a front subframe made from CDS. I expect final weight will be in the reigon of 1050kg. I've given 500bhp as a target, but knowing the engine builder, this will be more likely 520-550bhp. I found a link to a performance calculator:

Power at Flywheel (BHP) : 525
Weight without Driver (KG) : 1050
Power to Weight Ratio (BHP Per Ton) : 508.03
0 - 60 (Secs) : 4.01
0 - 100 (Secs) : 7.81
60 - 100 (Secs) : 3.80
Quarter Mile (Secs) : 12.08
Terminal Speed (MPH) : 124.36
Drag Strip Quarter Mile (Secs) : 11.88
Drag Strip Terminal Speed (MPH) : 126.63

The 1/4 mile related stuff can be ignored because its not going to be set up for that, but in-gear times should be reasonable. I'm in the process of building another custom gearbox with theoretical vmax of 218 at 8000rpm, so I at least hope to nudge 190 (current official best in the Mk3 is 184.4 at Bruntingthorpe).

A cage isn't needed from a structural integrity point of view, although I suppose it would have been sensible to put one in from a safety perspective. I want to keep it looking as unassuming as possible.

Edited by mwstewart on Saturday 12th March 12:13

Nice project, but i think expecting those figures from a fwd car is a bit optimistic!

(not to mention a genuine 500bhp from a zetec is actually quite hard, and what transmission are you going to use to withstand the torque??)


(please don't think i'm knocking it, but i have a car with similar performance stats, it's rwd, and the transmission system alone cost £22k.)

[Max M4X WW]

mwstewart said:

I taught myself to spray and this is the first car I’ve ever painted.

Didn't you paint the white Ghia?

What happened to the Si trimmed recaro's?

[MonkeyBusiness]

Nice write up. Watching with interest.

[v8will]

Fantastic! bookmarked!!

[mwstewart]

sc4589 said:

Huge respect! I love that kind of project. Currently planning my own one which, granted, won't be as quick or probably as well specced, but I like it when cars are made into just overall user friendly projects. For the sake of a couple of hundred kgs, I'd rather have creature comforts AND massive performance...

Keep it up. This'll look really good when it's done. Have you considered maybe standard Ford alloys from a different model? Make it look like a secret factory model.

Cheers I would need to use a 17" OEM wheel to clear the brakes as I recently bought some 325mm AP two piece discs for the front (photos to follow shortly). I didn't realy want to go larger than 15", but the 16" Team Dynamics I have on order are no heavier than the standard fitment 14" alloys but still go over the AP's.

[mwstewart]

Max_Torque said:

Nice project, but i think expecting those figures from a fwd car is a bit optimistic!

(not to mention a genuine 500bhp from a zetec is actually quite hard, and what transmission are you going to use to withstand the torque??)


(please don't think i'm knocking it, but i have a car with similar performance stats, it's rwd, and the transmission system alone cost £22k.)

Thanks! I just punched in the numbers for a rough guide. I think the in gear times will be impressive but anything that involves a standing start (which I'm not interested in realy) will be laughable.

I started out with the Getrag MT285 6 speed, but the torue handling on that is less than Ford's own MTX75 - which is what I've gone for. There are a very good seletion of ratios and final drives available, and the 'boxes can still be bought new on eBay for a modest sum. There are a handful of 500+ Focus RS Mk1's which have proven the MTX is adequate, even on a 1/4 mile strip. Diff is the Quaife ATB (same as Focus RS).

500 from a Zetec is actually pretty straight-forward. The standard black top head flows sufficiently well for 400, but to make the extra I'm having a ported exhaust side, custom cams, oversize valves and double valve springs. The rod ratio is slightly altered over standard and I'm going for a dry sump due to a few high-hp Zetec's smashing the standard pump gears (root cause for this is not fully understood).

I appreciate 500bhp in a Fiesta sounds very much like "pub talk", but the engine is on the Dyno around may, so the figures should speak for themslves

[mwstewart]

Max M4X WW said:

Didn't you paint the white Ghia?

What happened to the Si trimmed recaro's?

I painted a few panels on that, using a one coat paint. I'm going for Recaro's now as the Si seats didn't really match the spec of the rest of the car

[shalmaneser]

what an incredible project! 500 bhp seems a tad excessive to me but more power to you for giving it a go (no pun intended (lol)).

Best of luck.

[soad]

Gulp! Not shy on power then

[anonymous-user]

mwstewart said:

Thanks! I just punched in the numbers for a rough guide. I think the in gear times will be impressive but anything that involves a standing start (which I'm not interested in realy) will be laughable.

I suspect it will feel dam fast whatever the clock says!! ;-)

The transmission really will make or break this one! having taken an RS (std 215bhp) with 7 miles on the clock, and 4weeks later returned it with 8000miles and a transmission with more lash than a very lashy thing, the limits of the box will become very evident if you are pushing big torque numbers.

I'm not too sure that 500bhp is that easy in a zetec tbh, 400 yeah, but 500 (250bhp/litre!) needs revs really, and things start to fall apart when you are running big boost at high rpm........


Whatever the outcome, i look forwards to seeing some vid of the finished beasty!!!

[Old Gregg]

v8will said:

Fantastic! bookmarked!!

Yep, me too. Amazing work and dedication, OP, I'm looking forwar to following this.

What does CDS stand for though?

[mwstewart]

Max_Torque said:

I suspect it will feel dam fast whatever the clock says!! ;-)

The transmission really will make or break this one! having taken an RS (std 215bhp) with 7 miles on the clock, and 4weeks later returned it with 8000miles and a transmission with more lash than a very lashy thing, the limits of the box will become very evident if you are pushing big torque numbers.

I'm not too sure that 500bhp is that easy in a zetec tbh, 400 yeah, but 500 (250bhp/litre!) needs revs really, and things start to fall apart when you are running big boost at high rpm........


Whatever the outcome, i look forwards to seeing some vid of the finished beasty!!!

Hopefully I've asked for a 7k RPM cap for exactly those reasons. I don't expect the gearbox to last forver but I do expect the engine to last for 20k,Ian has assured me that my targets will be met. Turbo choice is crucial in my case and a custom spec unit will be ordered.

I think you unfortunately suffered at the hands of a manufacturing defect there, as there are too many high power cars with the MTX that haven't had issues. This guy: http://www.rsownersclub.co.uk/rsocbb/showthread.ph... has run 500bhp through his for more than a few thosuand miles now, and there are no issues to report.

Target date for completion is July, I'm looking forward to it