V8 Ford Focus - The Flexus

Its been requested that I start a build thread on here for my V8 Mk1 Focus so here goes...

bit of background - Ive wanted something V8 for a while, the sound of a C63 Mercedes gets my juices flowing so I had to scratch that itch. trouble is mercs are expensive, likewise the engines are expensive, so I went on the lookout for a cheap V8 - anythign german was out of the question straight away.

So I didn’t want anything pushrod and old and I wanted something of modern tech that could push a bit of power - ideally wanted a manual but rocking horses don’t s**t apparently.
So I settled for this after a Saturday night on eBay...



Billy bargain at just over 400 notes, drove it all the way to south wales from eastbourne with the most horrendous steering knock i have ever encountered. Sounded like a machine gun when braking but I didnt care - it made V8 noises!

So not content with having the Lexarse, i wanted something smaller and lighter that i liked the look of and something that is known for handling fairly well and after a few days on scumtree I found this beauty (sarcasm intended)


And I like a challenge so I set about fitting the V8 into a Mk1 Ford focus ST170 henceforth affectionatley known as the Flexus

 

so first hurdle to overcome was how to make a FWD car into a RWD car.

next billy bargain was a 350z subframe on ebay



so i tried measuring it up on the car when it was on the driveway but it was rather difficult with all that focus stuff in the way so i set about moving it into the garage to strip the rear down to see what could be done

out with the old


in with the new




not without a few casualties mind...



so this was held in with some rather hefty mounts that from pure luck line up perfectly with the chassis rails at the front and only require some small modification of the rear mounts to get them sitting nicley. this was after countless hours of measuring wheel positions in arches but i got there in the end and its pretty damn good.



they were temporarily tacked in place just to see what the car looked like with its new rear end and i threw some random assortment of wheels on it to see what sort of width i was dealing with



onto the next issue...

the tunnel

 

before tinkering with the tunnel, i first had to make space - so out came the engine...


and of course I had to get the V8 out too..



so i just plonked it in too see what needed to be cut - because lets be fair this wasnt going to be a straight fit!





full disclousre - i cheated

it sat there, far too low resting on some jacks and blocks of wood. the good news was it fits in all directions...

well the engine did anyway...



the gearbox took its own casualties!

 

So the engine was "in" but the gearbox wasn't


that's the gearbox mount and the chassis rails, some arbitrary limit i set myself to have the bottom of the gearbox reach so it had to go up. as witnessed in the previous post there was no room - so i got carried away with the angle grinder....



I welded those temporary plates in to make sure the dash bar was supported as i have set myself another un-achieveble goal - because a V8 in a focus clearly wasn't difficult enough

Un-achievable goal number 2 - the interior must look as standard as reasonably possible as i cant be bothered pissing about with interior plastics and finding solutions to making it look pretty, metal i can weld, plastic sucks

so the gearbox could be moved up and it now fit...


with a moderate amount of clearance inside.

there was however a new problem on the horizon...


that little notch in the inner arch is to allow the steering rack arms to bounce up and down with the wheels, gives you a rough idea where the steering rack lives in the focus.

*hint* its where the engine is right now!

time to crack out the grinder

 

so heres the front subframe for the focus, mostly stripped bare and with a big chunk out of the middle because thats where the engine goes. temporary supports kept the 2 sides together at the correct levels and i could throw it in the car with the engine to see what kind of mess i had made myself.


turns out i made quite a mess and all of this needs to be done in a certain way before i can achieve my end goal.

so first thing was get the engine mounted correctly - nothing was in the way now so theres no reason it cant be the obstacle i build everything else around. so i fabricobled this monstrosity together


Note - this doesn't stay thankfully

but it served a purpose for now so it held the front of the engine.

next the gearbox...
as luck would have it a package turned up


BMW 5 speed box and everything i needed to bolt it up to the 1UZ

so my indecision threw everything off and i had to get creative with the grinder again because even though its much shorter (and dear god much lighter!!! like by a factor of 10!!!) its fatter for that shorter length.



so i threw it on and test fit it in the hole



poor picture but it fits! time to make a mount! to the angle grinder!



this will get some support when i get to fully welding everything in, I'm even considering changing the design a little to help with the exhaust and make it stronger. but now i can get back to the previous problem

the steering

complimentary "yes a V8 does fit in a focus" picture

 

so the steering - I knew it would be complicated but good lord i spent days working this stuff out.

bottom line is the rack had to be moved, and the only place the rack could go was behind the front sump of the 1UZ. this means moving the rack way forward and down from its original position. this means whilst the hubs are rear steer on the focus the rack is in completely the wrong place to have it work.

so I swapped them side to side to make the hubs front steer.

those of you in the know, know how much of a pain in the ring this will be when it comes to steering geometry

for those of you that don't there were 2 major problems.

1 the geometry itself (akerman angles etc.)
2 the ford rack will turn the wrong way if i move it to the front (so turning the steering wheel left will turn the wheels right)

problem 2 turned out to be an easy fix


BMW 1 series steering rack

so i set about putting this in place...


eagle eyed will notice the mammoth hole in the firewall and the crossmember has changed - i really couldn't deal with the old one and this one works much better. also made a strong connection between the 2 original parts of the subframe to attach the rack to. and i boxed it all in to "finish" the subframe


so it all bolts in and out nicely now making it easy to change parts should i need to (i'm bound to need to at some point)

some time on the lathe and a serious burn later and i connected the focus steering column to the BMW rack




and it all fits in the car and works with only the smallest pinch point in the steering which I'm fairly confident will be taken out by the power steering when its connected.


hole in the car - rod to fit both ends - you get the idea

 

so problem number 2...

holy moley this took some time to work out, and I wont bore you with the details but the long and short of it is the steering arm needs to move along the same arc as the lower wishbone when the suspension goes through its range of travel.

so to do that I threw this together which moves the pivot point for the track rod end to the right place so the bottom arm and the track rod follow the same arc eliminating bump steer. To complete this i needed cardboard and friken lazers and a massive amount of trial and error


^this one was wrong!^


this one was closer to what i needed. as a template at least. it allowed me to check and it all works out well so that's a huge relief.

now i knew the length the track rod needed to be a knocked something up to fix it a bit better than the magyvered thing up there^


the only issue i have now is the rack going over centre when on full lock. to combat this i'm not going to let it go full lock. the BMW rack has way more travel than the focus rack anyway so its not a problem, in fact it would be a problem for the wheels and inner arches if it does travel all the way from left to right.

so next (and still yet to be done) is make those horrific "steering rack end moving contraptions" into something that looks like it will have a little strength at full lock with the weight of the car on the 1 wheel.

into autocad (because im not a complete heathen) to design these...



these are still yet to be made because i cant find anyone who will do them for less than the price of a kidney!!!

 

See above, manual conversion makes this whole thing much lighter. There’s not much difference between the Lexus and the Ford engine. The Ford engine was surprisingly heavy

New update showing yes it’s manual now

The steering rack cost £25 and the metal cost a few £ plus some time (which I enjoy anyway) a new subframe was difficult as I’d have to find a front steering frame and then there is nowhere on the car to bolt/weld it to

There was a snowballs chance in hell that’ll I was keeping the original steering geo as the actual engine was in the way, no amount of messing about with the sump would help with that particular nugget

 

So some may have noticed the wheels changed colour in that last post.

turns out they did - i bought some JR11's, 10.5 and 9.5 inch wide



yeah they dont fit

so I was on the search for some new wheels that fit.

speaking of fitting wheels, some may have recognised a problem.
ford wheel fitment 4x10 something
sneaky RWD Japanese sub frame on the back of the Flexus - 5x114.3
Didnt fancy different wheels as that tends to get expensive, so I went on the lookout for a suitable change for one of the axles.
I settled on changing the fronts to be 5x114.3, you cant get adaptors so I had to get creative.

step up the Honda S2000, being one of a few Japanese RWD cars it had the correct setup i needed to keep the focus hubs (see above reference steering) and not have a driveshaft running through the bearing.

here are the 2 different hubs together


and after a sesh on the lathe the centre from the S2000 fits as a replacement in the focus hubs



I may have got a bit too aggressive with this one so I didn't do the other one but I done a preliminary test fit and it works a treat so I will take care with the next one and i will either do some farbicobling with this one or get a new one to turn down.

I was then able to fit the aforementioned JR11's and subsequently change them for these wheels, which i think fit a lot better



so it technically has 4 wheels, 2 which can be steered and 2 which can be driven. counts as a finished car right?

 

So there was a few things left up front.
1 the engine needed to be refitted to clear the steering rack



with some complimentary new engine mounts that weren't torn and weren't horrendously expensive to replace (thanks toyota)


steering column fits nicely, engine is in and there's the hugest of gaps between the sump and the steering rack



and 2 as seen in some other pictures I added the focus Anti-roll bar, this was just like the hubs, flipped around and new mounting points jigged up


the engine mount holes were strengthened, ARB fixed correctly, Steering rack fitted to both subframe and cross mount (little worried about this, not gonna lie), ARBs just need some drop links, steering arms need those fancy adaptors, and the front corners are pretty much done minus a lick of paint and maybe a brake upgrade (heh!)

engine is pretty close to the rad too


plenty of room for an electric fan - not so much the viscous fan

 

throughout all of this engine in and engine out i've been experimenting with exhausts and how to get the gasses out of the bay. this is the sort of thing I'm after as it has to snake around mounts, boxes car etc.



this is subject to change as I continue with the tunnel and i get more or less room but its likely this will be how its routed. leading to this under the car


a pair of sports cats and a cross pipe (yeah i know i cocked that cross pipe up a little but ill suffer the consequences I'm sure when welding) which still needs its home clarified. either way its a narrow gap so it had to fit in a slot that is no more than 10mm wider than the total width of those cats.
I suppose that's what I get for trying to fit a shaft and a twin exhaust in a spot reserved for a single pipe exhaust.
I originally tied to fit the cats in the engine bay at roughly the same place as the standard 1UZ cats but the steering column was having none of it, so i compromised and put them under the car.

speaking of shafts...

I got a shaft with the box and conversion plate but its way too short (about 350mm too short) so I'm gonna have to get one made. and its currently holding up the exhaust fab which is also holding up some other things so its something I'm gonna have to splash out on soon.

one of the things that kind of goes hand in hand with all of this is the tunnel, which is where all this mess started. Now that I had everything in place I could start building the tunnel up.

To start somewhere with this I needed to find a place for this manual gear selector. a place which you may remember fits into the stupid unreasonable rules - interior must remain standard as possible.


first thing I done was go to a scrappy and cut that centre console out for the selector to fit into (and the really important bit underneath...


from that I was able to position the stick and cut the support shaft to length so it fits correctly in the car...


Nailed it! I think i might get away with this whole standard interior shenanigans.

which leads me to the present day...

I'm currently building the tunnel with the selector in the right place whilst sitting in the "drivers" seat making bwarp noises because I'm still a child inside!


ignore some of the welding its either really really good or horrific! I really hate working with sheet metal.
But the bright side is there's only the sides to go which allows me to understand how much room there is for exhaust and shaft so I can continue with the fun stuff.

I will update this when I've completed a little more and got a bit closer to having it rolling.

 

Massive restriction? Surely not as big as the turbine up front? (Yeah I may have neglected to mention there’s boost involved)

I’m severely restricted by space under the car for 2 pipes. The only other solution I thought of was maybe the 2 feeding into a 3” pipe instead of a pair of 2.5” pipes? And then diverging again at the rear to I can have a twin tail pipe.

I’m currently reworking the exhaust anyway to make the tunnel fabrication a bit easier and so now is the time to make my mind up