457bhp turbo S38B36-engined BMW E28


457hp turbo S38 E28

The appeal of the sleeper will never diminish because the idea of taking an unassuming car and giving it the power to embarrass far flashier machinery is one that will put a smile on any car enthusiast’s face, especially when you wipe the smile off the face of the owner of said flashy car. Any form of sleeper is great, but when it’s a classic that appeal goes through the roof because no one ever expects anything from an old car so to having something more elderly with a silly amount of power on tap is just a ludicrously entertaining proposition.

A turbocharged E28, then, is a car that’s going to be something we all instantly fall in love with and Gatis Babris’ example is just about the perfect classic sleeper build. Gatis hails from Riga, Latvia, not a place we’ve had many feature cars from but his E28 is flying the flag for modded Latvian BMs in a big way and Gatis is a big BM fan, but it’s rare for anyone to start their driving career in something Bavarian and his first car deserves a mention because it’s very different to the sort of thing we’re used to reading about. “My first car was a VAZ (Lada) 2101 in blue. I loved it so much as it was a true old-school RWD car without any electronic aids,” Gatis tells us.

“I honed my driving (and driving sideways) skills in winter on non-asphalted and icy roads, also on frozen lakes. Winters are normally so cold here that the ice on lakes can be 50cm thick which is enough to hold the car. I bought this car when I was only 16 years old, did crazy things in the village I grew up in, there were almost no police there to stop me,” he grins and having cut his teeth on a slice of pure retro rear-wheel- drive machinery it’s no surprise to see him behind the wheel of an equally old-school rear-wheel-drive BMW.

“I have been addicted to Bimmers from 13 years old – I believe there is some kind of magic in them, it doesn’t matter if they are young or old. I bought one as soon as I was able to afford it. Maybe it is because of sitting in the back seat of some BMWs in my childhood, I fell in love with the quality and details and this feeling is still with me, and I can say that my next car will certainly be BMW,” he says with a smile. “My first one was a 1987 E30, a four-door saloon with a 2.0-litre engine. I was 18 years old then and bought it right after I got my the driver’s license. I bought it as I was dreaming of that car and model for years back then and I thought that they looked very stylish inside, and also that the engine was so powerful (compared to the 1.1 in my VAZ 2101/ BA3 2101),” he laughs.

“The turbo setup consists of a custom BorgWarner item mated to a 40mm Turbosmart wastegate, a Tial blow-off valve and the exhaust system features an equal-length twin-scroll ceramic-coated manifold”

Needless to say, there were more than a few cars between that E30 and this E28, including the X6 M50d he also owns as well as the 200SX Gatis built for Pro class drifting and which is currently running 760hp, so he’s clearly got a taste and talent for turbocharged machinery. So what led him to this E28? “I bought it over 10 years ago here in Latvia. It already had the M engine inside but was in very poor condition due to rust. Actually, it was so rusty that I decided not to rebuild it, but to buy a better body and transfer everything from this car into it. I was pretty happy with the outcome and loved to drive it, as that body had better suspension, brakes and so on. Compared to a stock E28 it was like night and day and the car was so good that it participated in the Latvian Auto Exotics car show in 2010 and 2017,” he smiles. The most interesting part of all that is the engine, which has gone on to become the centrepiece of this entire build and while the European M5 only ever came equipped with the M88, the previous owner of the E28 saw fit to stuff an S38B36 under the bonnet, so it’s no surprise that Gatis was so keen to snap the car up. “The previous owner planned to rebuild it for racing but needed money badly at some point, so he offered it to me and I couldn’t resist, keeping in mind how rare those engines are,” he grins and it was definitely the right decision as it led to the creation of the car you see here.

For many people, an S38-equipped E28 would already be more than enough and they’d call it quits right there, but Gatis had more on his mind. “Driving with the stock S38 was quite fun, but I wanted more and wasn’t very satisfied with the way those engines give you the power – all the fun is only near to the redline,” he says. “Also I was beaten at traffic light races from time to time. My idea was to add a turbocharger to the engine, it wasn’t very cheap but I knew it will repay me once it was done,” grins Gatis. He tasked a Latvian company called IRC with building him the perfect turbocharged S38 and as they normally build projects for racing this was right up their street. The S38 loves a bit of boost but there’s obviously a bit more to it than just slapping on a turbo and calling it a day; IRC have equipped this S38 with ARP bolts, a custom oil cooler and a Spal cooling fan, while the turbo setup consists of a custom BorgWarner item mated to a 40mm Turbosmart wastegate, a Tial blowoff valve and the exhaust system features an equal-length twin-scroll ceramic-coated manifold with an 89mm stainless steel downpipe leading to a 76mm exhaust with two resonators. There’s a large front-mount intercooler with aluminium pipework, a Walbro 525lph fuel pump, Siemens 850cc injectors and Audi coils, while VEMS engine management looks after everything.

“Right now I’m driving it with 457hp and 424lb tq pushing only 0.4 bar – this engine is able to handle a lot more, but I love it the way it is”

“The plan was to get 500 to 550hp, but when we started measuring the power on the dyno I was surprised with how good the torque curve was. When we pushed it a bit more (550hp and over 440lb ft), the stock clutch started to slip so we decided to stay at safe numbers,” explains Gatis. “At the moment it has 398lb ft at 3500 rpm, it gives me the pleasure of driving and a nice kick when I need it, already at midrevs,” he grins. “Right now I’m driving it with 457hp and 424lb ft of torque pushing only 0.4 bar – this engine is able to handle a lot more, but I love it the way it is,” he adds. “After the turbocharger installation and engine work was done I had to drive it gently for 1000km and I must say it was hard not to push that pedal,” he laughs. “But just driving on the street always resulted in a thumbs up from guys in other cars or just walking by, and the car was photographed all of the time by people driving behind it, but I wasn’t able to show them the real character of it. But when it was done and the engine was setup properly I celebrated this with my family,” he laughs. “All-in-all I’m quite satisfied with the outcome, as I got the perfect everyday driving engine with high torque and low horsepower that will go on for years, and it will keep the M5 engine, gearbox, diff etc. safe as they will cope with this power easily. Possibly I will push out more next year, but I will need to think about clutch modification then,” he adds but Gatis is clearly in no rush and we don’t blame him. This is a lot of power to have in any car, let alone an E28, and we like the fact that he’s not chasing numbers and is more interested in having a setup that is good to drive, and with so much torque on tap at low revs this is perfect, while at the same time not unduly stressing his engine or transmission.

The rest of the car has been kept extremely subtle and Gatis has really focused his attention under the bonnet, but this E28 wears a few elements that enhance it in exactly the right way. The stock E28 ride height was never going to do for him and a drop was required, with a set of Plaza shocks and H&R springs deemed to be the perfect combo and they work exceedingly well together, with this E28 now sitting perfectly while still remaining usable for daily driving, and it’s also been fully poly bushed for good measure. The right drop needs the right wheels and, fortunately for Gatis, his E28 already came with the right wheels; “I got the car with these on it, they are 17” three-piece BBS RS192s; my friend Kristaps refurbished them for me and I believe they are ideal choice for that car,” he says and we have to agree. You can’t go wrong with RSs on a classic BM and these look so good with their white centres and gold hardware so we’re not surprised Gatis decided to hang onto them. This E28 also wears the M Tech body kit, there are smoked rear lights and a very cool centre-exit exhaust, but otherwise, there’s nothing else here that you wouldn’t expect to see on a nice E28 and absolutely nothing to suggest that this particular example is packing some serious turbocharged power.

“The interior, meanwhile, has also been largely left alone, which is no bad thing, and there’s some patina and plenty of character in here, with the leather seats, dash and door cards combining to make it feel that little more luxurious”

The interior, meanwhile, has also been largely left alone, which is no bad thing, and there’s some patina and plenty of character in here, with the leather seats, dash and door cards combining to make it feel that little more luxurious. The only noticeable additions are the trio of custom-mounted auxiliary gauges ahead of the gear lever for boost, oil pressure and voltage, and Gatis has also had quite a substantial audio upgrade carried out, with sound deadening, uprated speakers, an Alpine head unit and the whole system was set up using a microphone when it was done to ensure it sounded perfect. “The end result is that you don’t feel like you’re in a car when you’re listening to music, more like a large auditorium, and I’ve even participated in audio events with it,” he says with a grin.

Gatis has owned his beloved E28 for over 10 years and two-and-a-half of those have been spent turning it into the turbocharged classic sleeper you see before you today. The subtle period styling teamed with those iconic RSs is the perfect combo while that massive turbo and S38 under the bonnet deliver some monster power that makes this 5 Series an absolute hooligan. “There are many modifications that I love on the car, but if I had to choose my favourites would be the engine and wheels; I love the way the car drives and the noise it produces – the engine has an external wastegate which makes the moments when the turbocharger kicks in noticeable, it’s so much fun!” he grins. “And the wheels make the car look complete. I almost sold them for €300 at some point, not knowing their real value, I’m so happy I didn’t do this,” he laughs.


The only plans Gatis has now are to get the seats retrimmed, get the paint refreshed, maybe aim for a bit more power once he has an uprated clutch on board but his main plan is just to enjoy it. “I want to drive it as far as possible, I want to take it to meets here and abroad and I’m planning to visit Gatebil in 2020,” he says, which will include a sea crossing and then a 400- mile drive across Sweden and Norway and that is guaranteed to be one hell of a trip, because this is one hell of an E28.

Turbo S38 E28

ENGINE AND TRANSMISSION 3.5-litre straight-six S38B36, ARP bolts, twinscroll ceramic-coated equal-length exhaust manifold, BMC air filter, custom BorgWarner turbocharger, 40mm Turbosmart external wastegate, Tial blow-off valve, front-mount intercooler, handmade aluminium intercooler pipework, Siemens 850cc injectors, Walbro 525lph fuel pump, in-tank fuel venting system, Teflon hoses with AN fittings, Audi coil packs, Spal cooling fan, custom crankcase breather, custom screenwash reservoir, 89mm stainless steel downpipe to 76mm exhaust system with two resonators, VEMS engine management. E28 535i five-speed manual gearbox and refurbished LSD, uprated axles

POWER AND TORQUE 457bhp and 424lb ft

CHASSIS 8.5×17” (front) and 9×17” (rear) BBS RS192 wheels with 225/45 (front and rear) tyres, Plaza shock absorbers, H&R springs, full poly bushed, E23 735i brakes

EXTERIOR M Tech body kit, smoked rear lights

INTERIOR Extended leather interior, Hartge 280km/h speedometer, auxiliary gauges for oil pressure, boost and voltage


Custom BorgWarner turbo helps make 457hp. Hartge 280km/h speedo has been fitted. Leather dash adds an air of Alpine head unit and auxiliary gauges luxury to the cabin. Gorgeous 17” BBS RSs All that power and torque makes for a lot of fun.

How useful was this post?

Click on a star to rate it!

Average rating 4.5 / 5. Vote count: 4

No votes so far! Be the first to rate this post.


Jean-Claude Landry
Jean-Claude is the Senior Editor at eManualOnline.com, Drive-My.com and Garagespot.com, and webmaster of TheMechanicDoctor.com. He has been a certified auto mechanic for the last 15 years, working for various car dealers and specialized repair shops. He turned towards blogging about cars and EVs in the hope of helping and inspiring the next generation of automotive technicians. He also loves cats, Johnny Cash and Subarus.