do88 Buyers Guide: What the Swedish Cooling Brand Is, and Which Part to Buy First

We list 471 do88 parts, and about 70 of them fit a BMW, from a $32.54 hose clamp kit for the E9x M3's S65 coolant hoses to a $3,734.01 MERA charge cooler manifold for the Gen 2 B58. A tuned owner rarely needs more than one or two of them to start, and the right one depends on where the engine loses power to heat.

This do88 BMW buyer's guide covers what the Swedish brand is, what its premium buys, and which do88 part to buy first on the N54, N55, S55, B58, S58 and S65. We sell do88 alongside CSF, Mishimoto, Dinan and Wagner Tuning, so where another brand is the better first buy, we say so.

Specs and test numbers come from do88's own product pages and development notes, owner reports from M3Post threads, and prices from our store. Prices vary by dealer.

Shop do88 for BMW

The Short Answer

Buy the do88 part that fixes your engine's first heat limit. N54 or N55 E chassis: the BigPack ($1,045.40 to $1,184.10). S55: the charge cooler ($1,713.55). Gen 1 B58: the heat exchanger ($744.71). S58: the heat exchanger ($813.01). S65 M3: the radiator ($712.00). Gen 2 B58 and Supra: another brand's heat exchanger first, then do88's auxiliary radiators for track.

What do88 Is, and How It Builds BMW Parts

do88 is a Swedish company founded in 2007 in Nykvarn, outside Stockholm, that began by selling universal silicone hoses and grew into model specific intercoolers, radiators, oil coolers and intakes. Being Swedish, it started with Saab and Volvo, and our do88 catalog still shows it: 139 Volvo parts and 110 Saab parts against about 70 for BMW.

do88 says every product is developed in house. It borrows or buys the car, tests the factory part for a baseline, 3D scans the space, designs in CAD with airflow simulation, test fits a 3D printed mockup, then flow benches and track tests the finished part against the original. The results go on each product page with the conditions, which is more than most makers publish.

The clearest case for that approach is a test do88 ran on a 2006 Saab 9-3 V6. A universal front mount intercooler flowed 50 percent less air than the factory unit, and on the second back to back pull it ran 17°C (30°F) hotter at 200 km/h than do88's direct fit cooler in the stock location. It is do88's own test on a Saab, not a BMW, and do88 says so.

What You Pay For, and Where do88 Falls Short

With do88 you pay for direct fit parts backed by published test data, and you accept higher prices, a 12 month warranty and some recent quality complaints. On all five BMW parts below, do88 costs more than the CSF equivalent we stock.

The extra money buys bar and plate cores, TIG welded aluminum end tanks and silicone hoses with four layers of polyester and aramid reinforcement. It also buys numbers with conditions attached: do88 tested its S55 charge cooler on a bootmod3 Stage 1 car, back to back on the same day, and published 13 hp at peak and up to 25 hp in the midrange.

The limits are real too. The do88 listings we checked carry a 12 month warranty against material and manufacturing defects, while CSF backs its S55 charge cooler for life. Some parts need trimming despite the direct fit label: do88's own page for its Gen 2 B58 heat exchanger says the plastic radiator frame needs trimming, and S65 owners trim two tabs for the radiator. And E9x M3 owners have posted weld complaints, covered below.

Which do88 BMW Part First, by Engine

The first do88 part is whichever one cools the circuit your engine overheats first: charge air on the turbo engines, coolant and oil on the S65. This table sums up the sections below.

N54 and N55, E chassis: the BigPack

On a tuned 135i or 335i the BigPack is the right first buy because it fixes the heat and the plastic charge pipe in one install. The do88 N54 BigPack ($1,045.40) pairs an intercooler with 124 percent more core volume than stock and a 3 inch aluminum charge pipe, and do88 measured 43°C post intercooler air against 58°C stock under matched conditions. The N55 version ($1,184.10) adds a turbo outlet hose, and do88 logged 13 hp at peak on a Stage 1 335xi.

On a tight budget, the plastic pipe matters more than the core: our charge pipe guide says replace it on these engines tuned or not, and do88's alone is $302.42 for the N54 or $281.58 for the N55. Then comes the aluminum radiator ($642.44, manual and automatic versions) and, on the N54, the $687.10 silicone coolant hose kit, since every original hose on these cars is well over a decade old.

N55, F chassis and the base M2: the intercooler

The F22 M235i, F30 335i, F32 435i and 2016 to 2018 base M2 use a front mount air to air intercooler, and do88's $867.27 unit measured 35°C against 57°C stock. The $314.91 charge pipe kit comes next. Base M2 track cars can add do88's remote radiator ($608.22) and oil cooler ($742.28).

S55: the charge cooler on the street, the radiators on track

On a tuned street F80 M3, F82 M4 or M2 Competition, the first do88 part is the charge cooler on top of the engine, because it fixes pull to pull fade. The do88 S55 performance intercooler ($1,713.55) has 85 percent more core volume, and do88 measured 39°C post cooler air against 48°C stock in 0 to 240 km/h runs.

Track cars add the front heat exchanger ($683.28) and right side radiator ($976.18), which together took post cooler air from 39°C to 34°C at 240 km/h in do88's testing, then the oil cooler ($672.13). CSF argues for the heat exchanger first if you can buy only one part; our S55 cooling guide weighs both views. The F8x BigPack ($3,705.07) bundles the charge cooler, both radiators and all three charge pipes for $322.16 less than buying them separately, but neither the side radiator nor the radiator BigPack fits the M2 Competition.

B58 Gen 1: heat exchanger first, manifold later

On an F22 M240i, F30 340i or F32 440i, the first do88 cooling part is the WC-420 heat exchanger, the radiator for the charge cooler loop. The do88 Gen 1 heat exchanger ($744.71) has a 2 row, 48 mm triple pass core with 66 percent more volume than stock. If the factory plastic charge pipe is still on the car, do88's $478.25 aluminum pipe goes on first, with the first flash.

Our B58 cooling guide sets the order: heat exchanger first, auxiliary radiators second. do88's Gen 1 manifold ($2,325.20) is the bigger step, with an 11 row core against the factory 6, and do88 measured 26°C charge air against 40°C stock. Owner logs show a heat exchanger mostly speeds recovery, so we'd buy the manifold only for track, drag or a bigger turbo. The G30 540i and G01 X3 M40i aren't listed for the WC-420, though the manifold and charge pipe fit them.

B58 Gen 2 and Supra: do88 comes second

On a G20 M340i, G22 M440i, G42 M240i, G29 Z4 or A90 Supra, the first cooling part is a heat exchanger, and we don't stock do88's. From our shelves that means Dinan ($403.95). do88 also makes a Gen 2 heat exchanger, listed at $800.20 on its own US site, which we don't stock. We do carry both of its Gen 2 charge cooler manifolds: the standard kit at $2,325.16 and the MERA at $3,734.01, which adds an auxiliary port injection fuel rail. do88 lists them for the A90 Supra, Z4 M40i, M240i, M340i, M440i, 540i, 640i, 740i and 840i, the X3 and X4 M40i and the X5, X6 and X7 40i with the Gen 2 B58, and mild hybrid cars need a small alternator modification covered in do88's instructions.

The do88 part that comes second is the auxiliary radiator pair ($490.95), and it cools the engine coolant circuit, not the charge cooler loop. That helps prevent "Engine too hot" warnings on track and does little for intake temperature on a street pull. do88 says BMW cars need the factory right side radiator fitted with option 33T. Track and drag cars can add do88's $628.03 transmission cooler for the ZF 8HP.

S58: the heat exchanger

On a G80 M3, G82 M4 or G87 M2, the first do88 part is the WC-430 front heat exchanger ($813.01): a 2 row, 48 mm quad pass core 39 percent larger than stock with 1.4 liters more coolant. Track cars add the oil cooler ($805.65) next, automatics the transmission cooler ($684.24), and auxiliary radiators ($610.50) only when coolant climbs. Our S58 cooling guide explains why oil is often the first S58 limit on track.

S65 E9x M3: the radiator, then the BigPack

On an E90, E92 or E93 M3, a street car with its original plastic tanked radiator should buy the do88 radiator first ($712.00), which ran 73°C against 79°C stock in do88's test. Track cars want the BigPack: radiator, oil cooler and power steering cooler for $1,972.92 on manuals, plus the DCT cooler for $3,041.98 on DCT cars. That saves $168.29 and $399.10 against separate parts. do88 measured oil at 84°C against 103°C and DCT fluid at 74°C against 90°C.

What Owners Actually Say

The most detailed do88 owner threads we could read are on M3Post, from E9x M3 owners who track their cars. We could not open the Bimmerpost threads on do88's turbo BMW parts, so logged results on the N54, S55, B58 and S58 live in our engine guides above and cover several brands.

The rebuild that ran hotter. An E92 M3 owner ran a full do88 cooling stack and called it cool at COTA. After a tire barrier crash wrecked the coolers, he fitted new do88 parts with another brand's oil cooler. With the new parts, coolant climbed from 200 to 230°F in half a lap on an 80°F day. A year later it hit 230°F within three laps at 65°F and put the car in limp mode, even after new OEM seals, ducting and lines. He was still testing other radiators, with no confirmed cause.

• E92 M3, 6-speed, Southern California. About two years and 6,000 miles on a do88 radiator, oil cooler and power steering cooler. Oil sat near 220°F through heat, autocross and canyon runs and never passed about 230°F. No leaks. Positive.
• 2011 M3 coupe and another E92. One owner rated his year old do88 radiator 9.6 out of 10 with no coolant loss after trimming two plastic tabs per do88's instructions. The other had no leaks but wished it had a drain plug, and his do88 oil cooler hit his aluminum skid tray until he bent it. Positive with fitment notes.
• Weld complaints. A 2011 M3 Competition owner found excess weld inside the lower neck of a new radiator, and another owner's radiator pack leaked at a side weld after two years. A BMW shop posted that it stopped selling do88 over defects, including an unfinished weld bead, and unanswered warranty emails. Another BigPack owner in the same thread reported no issues. Negative.
• 2008 M3 at Thunderhill. With a do88 oil cooler and a CSF radiator, oil ran about 270°F every session and peaked at 278°F on a 105°F day. Mixed: a bigger cooler buys margin, not immunity.

Mistakes We See

• Buying B58 auxiliary radiators for intake temps. They sit on the engine coolant circuit. A street car fading on the third pull needs a heat exchanger.
• Ordering the port injection rail for the wrong manifold. The $169.42 do88 rail fits only do88's own B58 manifolds, and the MERA versions already include it.
• Buying the S55 side radiator for an M2 Competition. It doesn't fit, and neither does the radiator BigPack. The charge cooler, front heat exchanger and oil cooler do.
• Skipping the box inspection. Given the weld reports, check welds and fittings when the part arrives, before coolant goes in. The warranty is 12 months.
• Starting with a manifold. On the B58 and S58, a manifold of $2,300 or more still sheds heat through the stock front heat exchanger. Do the heat exchanger first.

Who This Is For (and Who Should Skip It)

do88 is for tuned BMWs that do repeated hard pulls, track days or summers above 90°F, and for owners who value published test data and close factory fit over the lowest price. E9x M3 track owners and S55 owners who feel the second pull fade get the most from it.

Skip it on a stock street car; the factory cooling copes. If a lifetime warranty or the lowest price matters most, CSF costs about $20 to $125 less per part in the table above, and Mishimoto up to about $165 less. PWR, which we don't carry, is the other radiator name E9x M3 owners bring up.

If It Were Our Car

N54 135i or 335i on a Stage 2 map: the do88 BigPack, then the radiator before the next summer. F80 M3 or F82 M4, street tuned: the do88 charge cooler and nothing else until logs ask for more. Gen 1 340i or M240i: the do88 charge pipe with the first flash, then a heat exchanger. The WC-420 is the do88 pick; our B58 guide takes CSF's $695 unit on price.

M340i or Supra: Dinan's heat exchanger on the street; add do88's auxiliary radiators before the first track day. G80 M3 or G82 M4 on track: the WC-430 and do88 oil cooler together. E92 M3 track car: the BigPack, inspected on arrival. Owners split on S65 radiators lately, so we'd pressure test before install.

What do88 Pairs With

Cooling follows the tune and the downpipe, since those add the heat. On the N54, N55, S55 and Gen 1 B58, an aluminum charge pipe belongs in the same order, and do88 makes one for each. do88's port injection rail only makes sense once a do88 B58 manifold is on the car.

We are an authorized dealer for every brand we carry, and in stock hardware ships fast. Not sure which engine generation you have? Email us your VIN and we'll confirm fitment before you order.

Browse the do88 Range

The Bottom Line

do88 makes direct fit BMW cooling parts with published test conditions, and it charges more than CSF or Mishimoto for comparable parts. The first part follows the engine: BigPack on the N54 and N55, charge cooler on the S55, heat exchanger on the Gen 1 B58 and S58, radiator on the S65. On a Gen 2 B58 or Supra, Dinan's heat exchanger comes first and do88's auxiliary radiators second. Manifolds wait for track, drag or turbo builds. Inspect the welds on arrival.

Frequently Asked Questions

Is do88 worth the money over cheaper intercoolers?

On a tuned car that sees repeated pulls or track days, usually yes, because do88 parts fit the factory location and come with published test results. Expect to pay about $20 to $125 more per part than CSF, with a 12 month warranty.

Where is do88 from?

do88 is a Swedish company founded in 2007 in Nykvarn, outside Stockholm. It started with silicone hoses for Saab and Volvo and develops and tests every product in house.

Which do88 part should a B58 owner buy first?

On a Gen 1 F chassis car, the WC-420 heat exchanger at $744.71, after an aluminum charge pipe. On a Gen 2 car or Supra, start with the Dinan heat exchanger, then add do88's auxiliary radiators for track.

Do do88 auxiliary radiators lower B58 intake temps?

Not much. They cool the engine coolant circuit, so they prevent coolant based timing cuts and "Engine too hot" warnings on track rather than lowering intake temperature on a street pull.

What is a do88 BigPack?

A bundle of parts for one platform at a lower total than buying them separately. The F8x BigPack ($3,705.07) includes the charge cooler, both charge air radiators and the charge pipes, $322.16 less than the parts bought one by one.

Does do88 fit the M2 Competition?

Mostly. The S55 charge cooler, front heat exchanger, oil cooler and charge pipes fit the 2019 to 2020 M2 Competition, but the side mount radiator and the radiator BigPack do not.