ALL AMERICAN TAKE OVER
Fitting a massive Yank V8 lump into your BM is nothing new, but doing that and then strapping a pair of turbos on for good measure takes things to a whole other level….
Rebel yell Utterly insane twin-turbo V8 E30 with almost 900hp.
After tiring of turbo M20 reliability issues, Ross Bradley went back to his hot rod roots and rebuilt his E30 using American V8 power… with two turbos this time. Words: Ben Koflach. Photos: Matt Woods.
Meet Ross Bradley, an E30 nut who likes to do things his own way, particularly if it involves a twin-turbo V8. The story begins back in March 2010 when he bought this black 325i and, like so many of us, he formulated a plan to make it his own. “It was sitting on a drive for about four years with moss growing up the sides. I used to see it when I was out at work,” explains 35-year-old Ross. “It was pretty solid body-wise, so I offered the guy some money and bought it for £275. I got it home, changed the plugs and put fresh fuel in and it fired up first time!”
Fast forward a year or so and his E30 was something we’d all be proud to call our own, featuring Borbet A wheels, a nice drop in ride height and a full M Tech 2 body kit, among other tricks. However, having grown up around American hot rods and other powerful machinery, it was only a matter of time before the engine bay got something of a shake-up.
“I’ve always had turbo cars. I just have a passion for them,” Ross tells us. “And the BMW needed more power so the only way to go was turbo!” Ross laughs. The car’s transformation started with him taking the original M20 and turbocharging it, earning him the bragging rights of having over 400hp under his right foot. Having been an engineer by trade in the past he made it all look easy, building up the M20 with forged pistons, a custom intake plenum and plenty more goodies. Ross was happy until an oil pressure issue left him with a knocking bottom end and feeling thoroughly disheartened. Fortunately Ross isn’t the kind of guy to remain demoralised for long and he used this temporary upset as a chance to refocus. “I’ve always been a fan of proper V8s – not the little BMW ones but full-blown Ford or Chevy motors,” he explains. “Now that I had the chance, I decided to get rid of the old turbo engine which kept going wrong, and I sold all the parts to fund a new engine.”
Ross’s plan for Yank horsepower made good sense. “I considered the newer GM LS engines but at the time they cost more than a complete S50, and you can just as easily build an old type V8 with EFI for half the price.” A decision was made and Ross was soon the owner of a small-block, 350ci (5.7-litre) block ready for building up. While Ross pressed on with using the bare block for test-fitting purposes, his shopping list started becoming a reality. A #GM forged crank, Eagle forged rods, a hightorque starter motor, alloy roller rockers and a new sump all arrived, with Ross’s plans continuously evolving for how the engine would fit in the car and how it would be built.
“The gearbox I chose was the manual gearbox from the Mk3 Toyota Supra: the R154. With a couple of little mods they can be bombproof, but not cheap at £600 for the box alone!” Ross says. He was still waiting on engine parts but could at least get the gearbox built up. This would allow him to finalise the engine location once and for all.
All new bearings went in, along with an uprated first gear thrust washer, before the front end was built up with a Chevy bellhousing, hydraulic clutch release bearing and all the necessary conversion parts. What soon became clear was that the E30’s transmission tunnel just wasn’t going to be big enough. Luckily it wasn’t beyond the call of a few hour’s work with a hammer. The next obstacle was the crossmember and anti-roll bar. A conversion to an E36 anti-roll bar (which sits ahead of the crossmember) had that issue solved easily enough thanks to some fabrication work, but Ross also had to notch the crossmember for clearance and ended up moving the steering rack forwards by 20mm to clear the starter motor.
This left Ross with the small block sitting happily in his engine bay, as low and as far back as was possible. “The shifter even ended up in the right place!” laughs Ross. “There was just a sensor that I had to add clearance for, so things were going well.” With his engine and gearbox mounts fabricated, Ross then threw on the aluminium heads that he’d ordered and checked the clearance of everything with his turbo manifolds fresh from the States. Sure enough, his engine mounts had to come back out for some further clearance work and he had to make plans for relocating his brake servo and master cylinder to under the dashboard. For Ross this was all in a day’s work.
With the engine position decided, Ross pulled the V8 block back out so that he could finally start transforming it into a functioning engine. The local machine shop was tasked with boring out the cylinders by .030”, taking displacement to beyond the 5.8-litre mark. Probe forged pistons were mated to the Eagle rods, with the crank going in with Clevite bearings and ARP hardware. His camshaft of choice was a Comp Cams 256/263-degree grind, made especially for turbo applications.
Such is the aftermarket support for these engines that Ross managed to get his aforementioned aluminium cylinder heads for just £200 and set about porting them himself by hand to make the most of a set of massive Manley valves (2.02” inlet and 1.60” exhaust, in fact). This V8 may only have 16 valves but it makes up for that with sheer size. The heads were finished with Edelbrock valve springs and titanium retainers, which are operated by Comp Cams billet rockers and Edelbrock Magnum pushrods. No stone has been left unturned with this Yank powerhouse.
A good old Holley carb was initially used to get the engine running alongside a Megasquirt ECU and Ford coil packs. Ingeniously Ross used a few of the old M20 sensors and brackets to feed the ECU with all the needed info, which allows the V8 to run normally aspirated for a few miles as a gentle run-in. A huge Pro Cool radiator, a custom intercooler and a day’s worth of custom fab work by Ross got the E30 roadworthy but he was far from done.
When the time came to switch to fuel injection Ross, as usual, didn’t do things by halves. With the rear boot floor in bits (more on that in a moment) he plumbed together a fuel system capable of supplying enough jungle juice for the monstrous powerplant now sitting up front. A high-flow lift pump feeds a two-litre swirl pot, with twin Bosch 044 pumps then feeding the engine through front-to-rear braided AN lines. All that fuel is supplied to 770cc injectors mounted in an Edelbrock intake manifold, fitted with a 90mm Procomp throttle body.
That swirl pot setup is mounted onto a flat rear floor. Ross’s car has no spare wheel well and for a very good reason. With the extra power and monstrous torque that he was going to be feeding through the rear end, some serious reinforcement was needed. The entire rear beam was dropped and stripped and Ross’s work began.
The first thing on the ingredients list was an E28 large case diff; though it bolts right up to the E30 rear beam, that’s about where the compatibility ends; not a problem for someone like Ross. The beam was sent away for blasting and once back, he could begin. “I started by going over the old welds to make them a little stronger and I went around the trailing arm brackets again as some of them aren’t fully welded,” he explains. “Then I started the reinforcing.”
These reinforcements included plating over the diff mounts and bridging together the various factory joins with extra material. Bars were then also added between the diff mount and beam itself before a thick plate was placed over the diff recess. In short, Ross’s work is so solid we reckon it would withstand even a nuclear strike.
Next up was getting that diff mounted up. The E30’s single-ear rear diff mounting is famed for a lack of strength and so after some experimenting Ross found that an E36 M3 Evo diff cover and mounting bracket would bolt up to the E28 diff (with the addition of a spacer he made), giving him two ears to mount with. However, the E30 doesn’t have the provisions to bolt such an arrangement up, hence Ross had cut the boot floor out of his. A new crossmember was made out of box section, bridging the chassis rails and including mounts for that large case diff and the anti-roll bar brackets.
“With the rear crossmember done I started the rear strut bracing,” Ross tells us. This included strengthening plates on the rear strut towers along with a welded-in strut brace. This was then joined to the diffmounting crossmember with a set of bars tying the whole lot together for maximum rigidity before everything could be sheeted over to form a new floor.
The trailing arms were also braced with bars and then the whole lot bolted back under the car, complete with the new diff and a revision of Ross’s UJ driveshafts. However, he still wasn’t done, using the opportunity to also convert the car to fivestud all-round. Rather than the usual way, this arrangement was completed using Compact or Z3 parts with a bit of a custom setup. This consisted of Z3 wheel bearings and hubs, which needed a little machining to fit. “I used 300mm Z4 discs on the Z3 hubs, and then used Porsche Boxster Brembo fourpot calipers,” smiles Ross.
Up front the E30 stub axles were sleeved to allow E36 wheel bearings and hubs to be used, enabling the use of an XYZ brake kit. It was originally meant for a Japanese application using a 5x114.7 PCD and Ross also had to make his own brackets, too. Nothing phases this E30 fanatic.
Of course, the most noticeable change Ross had to make was to fit new wheels. The old 4x100 Borbet As would no longer fit but Ross found something else that would work nicely. It doesn’t get much better than three-piece Hartges, made by OZ back in the day. He found them in Poland and had them shipped over. They had polished lips and gold centres, which looked great, but weren’t quite what Ross had in mind. Therefore the wheels were stripped right down for the centres and lips to be repolished, and a lack of centre caps saw Ross approaching UK firm and BMW specialist Hack Engineering to reproduce the original plastic caps in billet aluminium so that it could all be polished up with the same mirror shine. Mirror-polished hardware finished the wheels off, with grippy Federal RSR tyres put in charge of getting all that power down.
This meant that phase two of the build was complete, and Ross enjoyed using it for the latter half of last year’s show season, clocking up the miles attending every show possible. Having witnessed it personally, we can confirm that when Ross’s E30 pulls up at the showground, a serious number of heads turn thanks to the appearance of a tidy E30 with the soundtrack of a lumpy, all-American V8. It really is quite something.
The way Ross has gone about building his E30 is like no other. While absolutely nothing on the car itself can be considered off-the-shelf, he’s also shown incredible ingenuity when it comes to building a reliable powerplant thanks to the strength (and low prices) of the American aftermarket. In fact, though untested, it’s estimated that the junkyard-rescued small block is currently pushing around 880hp and 750lb ft at 1.3bar. Could American power in an E30 be the way to go? You wouldn’t want to argue otherwise after seeing this machine.
Boot houses fuel system with two-litre swirl pot and twin Bosch 044 fuel pumps.
If you’re a keen show-goer in the UK you’re likely to see Ross’s monster throughout the year. However, do be warned – by the time it’s show season the E30 will be looking quite different. Ross didn’t want to tell us exactly what he was up to but you can rest assured that the E30 will be even better, very soon.
DATA FILE #Twin-turbo #V8 / #BMW-E30 / #BMW / #BMW-E30-V8 / #Bosch-044 / #Garrett-T04E / #Garrett /
ENGINE #Chevrolet-small-block-V8 , rebored 0.030” to 5.82-litre, #GM / #GM-V8 forged crank, #ARP main studs, #Eagle H-section forged con rods, #Clevite big end bearings, Probe oversized forged pistons, high volume oil pump, ported and polished alloy heads, #Manley-Severe-Duty stainless steel swirl-polished oversized valves (2.02” inlet, 1.6” exhaust), Edelbrock valve springs with titanium retainers, #Cloyes three-piece solid timing gears, Clevite cam bearings, Comp Cams 256/263-degree blower cam and lifters, #Edelbrock #Magnum chromoly pushrods, #Comp-Cams 1.5:1 alloy roller rockers, #Brodix rocker covers, ARP hardware (rocker arm studs, intake manifold bolts, sump bolts, timing cover bolts, engine mount bolts, exhaust header bolts, crank pulley bolts, bellhousing bolts), ARP oil pump driveshaft, custom engine mounts, customised turbo headers, twin Garrett T04E turbos, Tial wastegates, custom twin 3” turbo-back exhaust with Simons silencer, custom intercooler, Tial dump valve, #Edelbrock Pro-flo inlet and matching fuel rails, #Procomp 90mm throttle body, 770cc injectors, swirl pot with high flow lift pump, twin #Bosch 044 engine feed pumps, #Torques fuel pressure regulator, #March serpentine pulley kit, #Pro-Cool alloy radiator, #Megasquirt ECU, Ford coil packs, fully lightened and balanced flywheel
TRANSMISSION #Toyota-Supra-R154 gearbox rebuilt and uprated with #Marlin-Crawler thrust washer bearing retainer and selector forks, #McLeod clutch release bearing, #ARP clutch bolts, Spec R Stage 4+ paddle clutch, alloy fluid reservoir, #Cube shifter, custom propshaft, E28 210mm LSD with 3.07 final drive and M3 Evo twin-ear rear mount, custom driveshafts with #UJs , custom gearbox crossmember
CHASSIS 17x9” ET25 (front) and 17x10” ET20 (rear) Hartge fully polished three-piece wheels, 215/40 and 235/40 Federal RSR tyres, modified front crossmember for engine clearance, reinforced rear beam, E36 M3 front anti-roll bar with custom mounts and rosejointed droplinks, reinforced rear trailing arms, custom rear strut brace tied into custom rear diff mounting bar, #GAZ coilovers, GAZ adjustable front top mounts, stainless steel steering linkage joints and custom linkage, steering rack moved 20mm forwards, alloy power steering reservoir and custom lines, incar brake servo conversion using Renault Clio servo, VW Sharan brake master cylinder, #XYZ six-pot front calipers and 330mm discs, fivelug conversion using E36 and Z3 hubs, Porsche #Brembo six-pot rear calipers, #Apec-Z4 rear discs
EXTERIOR M Tech 2 body kit, carbon bonnet, E36 M3-style mirrors, widened rear arches, smoked rear lights, smoked front indicators, yellow foglights
INTERIOR Full red leather Sport interior, black carpets, custom gauge illumination (blue with red needles), A-pillar mounted auxiliary gauges (boost, #AFR , oil pressure), fuel system in boot
THANKS Dad for all of the paintwork, Shaun from V8 Development for all the mapping and wiring.
Red leather Sport interior looks fantastic and features custom gauge illumination and auxiliary gauges in the A-pillar.
I’ve always been a fan of proper V8s… full blown Ford or #Chevy-motors .