Ares: E30-LS1 – Removable Core Support

Timeline

Welcome to the second installment of the E30-LS1 Build.

Here we discuss a topic that is on every E30 enthusiast’s mind – How to effectively make the radiator core support removable. And this is just the first of 2 parts discussing this very in-depth topic.

To start, we’d like to quantify this discussion. Let’s list out the requirements:

  1. Must be easy/quick to remove – Mechanically & Electrically
  2. Must be relatively simple to construct
  3. Must look stock
  4. Must maintain stock functionality

Historically, an easily removable assembly, whether it be a subframe, engine, radiator, or any other subassembly of a rally or race car is key in order to get it back in the race. Here, we try to replicate that to the best of our ability in Ares. Below is a rough list of the pros and cons to doing such a modification. Also are a small list of items that could make/break your effort. This write-up is designed to de-risk your project and execute a professional looking E30 Front Subframe:

Pros Cons

 

How to cut the core? We performed a combination of drilling out existing spot welds with cutting and re-welding our own support structure to maintain stability and strength of the assembly. See below for cutting/drilling locations:

Radiator Core0

There are certainly many methods to incorporate a removable core support while maintaining to all of these requirements, but we will show you at a high level how we plan to execute that with Ares.

Here we have our documented main attachment points. These points must be, strong and somewhat concealed, while maintaining ease of accessibility with hand tools. Below you’ll see the basic structure of Garagistic’s go-forward approach when constructing to all of this criteria.

Radiator Core

The prototype modifications have been made as shown below. You can see where it was decided to make the connections. Each of these mechanical connections shall have either weld nuts attached or the holes tapped for ease of installation/removal. All tapped holes shall have at least 3 threads to meet the minimum torque requirements for a thread of that size.e30-removable-core-support (29)

e30-removable-core-support (26)   e30-removable-core-support (52)

Above are some pictures of the entire assembly after construction has been conceptualized.

Now let’s go back to our criteria – our requirements for our removable subframe. See below for the responses to our self-induced requirements.

  1. Must be easy/quick to remove – Mechanically & Electrically
    1. 6 Bolts, assembly pulls out by pulling toward the front of the car. No binding occurs
    2. C101/X20 style connector mounted directly on the fender wall near the ABS Pump
    3. Removal/installation of the core support and supporting structure will take no more than 10 minutes, including bumper, valence, core support, headlights..etc.
  2. Must be relatively simple to construct
    1. Basic welding knowledge, making steel brackets, and welding nuts or tapping for ease of remove/install.
    2. Need die grinder, angle grinder to make brackets and sheet metal bracing
  3. Must look stock
    1. Utilized existing support with modifications.
    2. Holds factory E30 radiator or an aftermarket Moshimoto with stock mount locations
  4. Must maintain stock functionality
    1. All electrical signals maintained
    2. Mounting points easily accessible.
    3. Maintains stock strength

More info to come in the second installment as we finalize our electrical routing! Because many of the signals require 10-12 gauge wire, we cannot use a simple aftermarket connector. Therefore, we plan to use a lightly used C101/X20 style connector and mounting it bulkhead in the side of the fender, thereby concealing the routing of the wires from the fuse box to the front end of the car. This helps the project remain inexpensive, available connectors, and no special pin/depin tools. The signals involved are:

Wiring

e30-removable-core-support (2)

Want more detail? Stay tuned for the official write-up of the E30-LS1 through Macalent LLC. There’ll be much  more detail with step-by-step instructions on how to on the construction of the removable core support, hardware listing, hole drilling for spot welds, measurements,  and suggested wiring for the one-connector hookup, making this super easy for the shady-tree mechanic.

Thanks for reading and continue to stay tuned for regular updates on this amazing project!

Introducing the God of War: Ares, The Formidable E30 – LS1

LS1 Timeline

The time has come…and the schedule above confirms!

That’s right! This is the start of WEEKLY updates to our most recent and proudest build. You’ll get the opportunity to follow us with fresh new status each week. You’ll also get a chance to learn all about the inner workings of the LS1 and what makes it so popular in today’s car culture. But most importantly once the build is complete, you’ll have the knowledge to complete this swap yourself.

So here we are, collecting parts, making jigs, stocking up on raw material, and getting psyched to keep you all updated every step of the way!

The 1997-2005 General Motors Engine “LS1” is one of the most popular engines in the modern automotive tuning realm. First introduced in 1997 Corvette and then in 1998-2002 in the Camaro Z28.

LS1

Why is it so damn popular?  Well, here’s a start:

  • Lightweight – Aluminum block option, aluminum heads that flow so well from the factory, and don’t often weigh much more than the 4cyl/6cyl iron blocks they replaced.
  • Simple – One Single Center Camshaft w/ pushrods, easy tune-ups. Low end “Y” Block has the fewest main bolts (6 bolts, 4 cap and 2 cross). One piece pan gasket with an oil pan that actually provides structural rigidity to the assembly.
  • Compact Power/lb – +/-350hp and +/-365lb-ft, depending on year
  • Attainable – Almost overabundant! Find it in the Camaro, Corvette, GTO, Firebird. Chevy trucks came with iron-block 4.8L/ 5.3L. And the 6.0L/6.2L engines were aluminum. Most of the car engines came in 5.3L, 5.7L, 6.0L, 6.2L and 7.0L sizes. Not only are there options when deciding on displacement, there are also choices when deciding if you want an iron or aluminum block. More on this below…
  • Reliable – High Mileage LS1’s with tons of field data, Extra Long Head Bolts to reduce variation in mass production.
  • Aftermarket – Replacement parts are cheap, not only because of the inherent mass production, but also that it’s american, making parts produced from hundreds of american manufacturers. Add a performance camshaft, Exhaust Headers, free flow intake and a free flow exhaust setup. just that will source you 400rwhp.
  • Fuel Economy – Could push up to 30mpg!
  • Price/Power Ratio – Off the charts. You can pick it up at the junkyard, do regular maintenance and get yourself an amazing swapped car.

Aluminum block really better? Actually yes…

Aluminum is better because it’s lighter (about 100# less compared to it iron LS1 counterpart), but requires iron sleeves. It cools better, and therefore extracts the heat through the coolant quicker than iron.

Iron is cheap, strong, can take a beating, and is great for turbo-charging over 1000rwhp. this version was primarily used in the Chevy Trucks.

In the end, aluminum is the future and best candidate for most tuners’ applications.

Let’s get technical. Here are the 5.7L Aluminum Block LS1 specs:

  • Block: 319-T5 Aluminum, 90deg, Deep skirt with cast-in iron sleeves. (careful with a stroker kit though)
  • Head: 356-T6 Aluminum, Cross flow, wedge combustion chamber.
  • Pistons: Cast Aluminum, Flat Top, 15.5oz Ea
  • Bore: 3.898 in, 4.4in Spacing
  • Stroke: 3.62 in
  • Displacement: 8*3.14* (Bore/2) * (Bore/2) * Stroke = 345.7 cu in (or 5.7L)
  • Valve  Intake: 2.00″ Dia, 200 deg, 0.5″ lift, 0.05″ duration
  • Valve Exhaust: 1.55″ Dia, 203 deg, 0.5″ lift, 0.05″ duration
  • Head Gasket: 0.052″ Compressed
  • Compression Ratio: 10.1:1
  • Firing Order: 1-8-7-2-6-5-4-3
  • Ignition: One COP (coil on plug) per cylinder. Saturation achieved in only 2 revolutions (4 in predecessor).
  • Crate Weight: ~390#
  • Spark Plug Gap: 0.06″
  • Bearing Caps: 4 vertical bolts, 2 cross bolts
  • Induction Type: One-Piece Composite Intake
  • Throttle Body Dia: 75.0mm
  • Transmission: Borg Warner / Tremec T56 6-Speed Gearbox

Tremec vs. Borg Warner:

TheT-56 was initially developed/built by Borg Warner. They were available in the 93-97 LT-1 cars (iron block). In1997, Borg Warner sold the T-56 out to a company called Tremec. Tremec began building the T-56 transmissions in Mexico out of inferior parts with cheap/weak synchros and gears. Every 6-Speed transmission you find in an LS1 Camaro, Firebird or Corvette is from the Mexican company Tremec T-56. Predominately early failure of the synchros are observed, causing the transmission to bind, grind, and whine.

Rebuilding a T-56 takes specialty equipment, expensive parts, and extremely detailed knowledge base in order to execute effectively.

So here we have Ares. Our signature V8 e30 ls1 build, sharing with our fans every step of the build. There’s a reason why they say the LS1 was built by the hands of God; The God of War – Ares.

And that’s exactly what we’re introducing to you. The BMW E30 colliding with the most ubiquitous, powerful, and insanely compact engine: The LS1.

 

(Image courtesy of lsxtv.com)

St patricks day sale + Blog facelift!

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3/17/16
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St Patricks day sale and newsletter!
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St patricks day sale + Blog is offically live!

Not only did we launch our new blog, we have also been busy making new parts! Be sure to see the new products and lots of specials going on for this weekend only. These items include: Complete poly suspension kit, e30 HD motor and trans bushings set, E36/E46 Poly RTABs, E30 is splitter sale, e30 to e36/e46 steering rack swap kit, Garagistic swag t-shirts, LED OBC sale, and more below!

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blog is live
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E30 complete poly bushings kit

Normal price = $245 Sale price = $200!
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http://store.garagistic.com/E30-front-strut-bar

E30 splitters are 40% off!

Normal price = $78 Sale price = $45!
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“Our partner, Macalent LLC, is proud to offer a 30% off discount on M30, M60, M62/S62 swap guides. Click below for convenient access to take advantage of this offer!”
Discounts not valid on past or pending orders. Not redeemable for credit. “shipped price is in USA only” Other restrictions apply. 

E36/E46 Rear Trailing Arm Bushing Symptoms

It was my one year wedding anniversary, and I decided to take my wife down to PA for the weekend to a bed and breakfast. We decided to take my wife’s 1997 328i because it was the best on gas and has been relatively reliable. On our way down I-81, we hit a medium sized pothole when going through a curve. It was at that point that I felt a somewhat apparent skip, or tug, to the outside of the curve on the e36. The Pennsylvania roadways are known for their never ending road work and I didn’t think anything of it because after all, I-81 is not kind to your suspension. Within the next 250 miles of travel, this skipping got slightly worse. And I realized that it wasn’t simply going over bumps and blips at high speeds. That didn’t bother me. In fact, skips in the suspension while going over bumps on a straightaway was manageable, practically imperceptible. The issue was going over these highway bumps on curves. That’s how I was able to isolate the behavior. But I was still in denial at this point, thinking to myself that it’s all in my head. Not to mention, I didn’t want it to ruin my weekend.

By the time we got to our destination 4hrs later, I couldn’t take it anymore. Even my wife asked, “what was that?”. I didn’t understand much about the E36 suspension at the time, but knew enough to know that it was coming from the rear of the car.

We parked at our bed and breakfast and I did what any BMW owner does first. Kick and push/pull the tires to identify anything grossly loose. Nothing. But I was so concerned that the next day I interrupted our Saturday afternoon activities by bringing the car to an independent shop and having the car put on a lift. And I’m glad I did! It was then and there that I found the glaring problem. And it was the rear trailing arm bushings, only one of them to be exact. Being an E30 aficionado, I quickly realized that the rear suspension design was nothing like the E36 equivalent.

If you take a look below, you’ll see the differences between the E30 and the newer E36 rear trailing arm bushings. And to save you the suspense, the E46 bushings are identical to the E36 style.

e30 e36 comparion

The E36/E46 trailing arm bushings sit inside of a metal enclosure, or “holster” if you will. Connected to the frame by a mere 3 bolts that are easily accessible. Just lift the car, take off the wheel, and remove the bolts as I indicated below:

  • Yes, the trailing arm will easily drop down.
  • Yes, it exposes the main bushing bolt you need to remove the metal enclosure very easily.

But Yes, you must continue to maintain pressure on the trailing arm downward in order to expose that accessibility. It wants to spring back toward the frame. Nothing that can’t be fixed with a piece of wood wedge between the trailing arm and the body.

  • No, it’s not easy removing the old bushing. You must cut the old out with a sawzall, or get lucky enough to press it out like below.
  • No, re-installing the new rubber bushing is not easy. In fact you need a homemade press to get this done.

You see, after this issue came up, I researched the heck out of it, and I determined that these bushings are quite easy to replace. Again, if you want to go stock rubber, you’ll have the added complication of making your own press to get the old bushing out and the new rubber bushing in. This can be harder than you think. Urethane bushings are a popular and tasteful upgrade to your E36/E46 rear suspension, but also are so much easier to install in that you do not need a press!!

e36 rear tab

Hey, at least you’re not dealing with replacing the E30 rear subframe bushings. See below for a quick comparison. It’s no picnic.

E30 E36 rear tabs

Upon closer inspection of my faulty E36 trailing arm bushing, I had mixed emotions. First, I was relieved that I found the part, and that this failure is a probable explanation for the behavior of the car on the highway, especially at highway speeds and on turns. However, based on how bad the old rubber bushing was, I didn’t know how in the world the car was able to function!!

The second discovered the issue, threw the indy shop $40 for his troubles, ordered the Garagistic E36/E46 urethane bushings and replaced them in a couple days later. Good as new. I got the 80A for the comfort version. In no way, shape, or form was my E36 going to be a race car!

garagistic parts

Nevertheless, I crawled home the next day, received the parts soon thereafter, and replaced both bushings in my garage with nothing more than a few hand tools, and the sawzall of course. After that, my E36 drove beautifully!

In the end, the car was repaired, thanks to Garagistics’s quick turn-around of quality parts, and I was able to drive it like I stole my wife’s 173k mile 328i!

Thanks for reading and stay tuned!

– Frank Macaluso

 

 

(main photo credit by:BBS Racing/RIH)

TOP-10 E30 Performance Mods

THE BANG-FOR-YOUR-BUCK LIST

There has been an ongoing debate for decades regarding the top bang-for-buck mods for your e30. And even then, there is a subjective criticism on what is cheap and what is expensive. Here is your one-stop shop for the top 10 mods for your e30, including risks, benefit, and yes even persuasion into getting onto the track to give these products a try.

  1. BACK-TO-STOCK

Don’t underestimate the value and importance of getting your E30 stock functions working! There are a wide variety of products available to get your car that modern look/feel, yet maintain that stock feel including ‘is lips, frequently burnt replacement LED OBC lightbars and Odometer gears. Gotta get that E30 working and looking good before doing any modifications!

back to stock

There are many other items that are necessary including proper alignment, suspension refresh, and of course, no oil/coolant/fluid leaks!

  1. PERFORMANCE CHIP

A performance chip is probably one of the most impacting upgrades to your E30. Depending on your model, some benefit more than others. Here’s a short list of the gains you can typically see with a chip: These are ranges not specific to any manufacturer

 

87-92 325i 90-91 318i 85-87 325e 88-91 M3
Engine Type M20B25 M42B18 M20B27 S14B23 / S14B25
Horsepower +15 @ 5,000 RPM +13 @ 5,500 RPM +23 @ 4,500 RPM +25 @ 7,600 RPM
Torque +15 @ 5,000 RPM +15 @ 2,500 RPM +28 @ 4,500 RPM +18 @ 6,000 RPM
Rev Limit 6,900 RPM 6,900 RPM 5,300 RPM 7,800 RPM

 

Chips typically range from $225-$300. Do Not Buy Ebay. Not only will you see no gains if you install one of these chips, you can also damage your engine.  A small list of vendors that supply chips include MarkD, TurnerMotorsport (Jim Conforti), Bavauto, Dinan…etc.

Installation is a snap with a simple removal of the ECU, dislodging the chip, and inserting the new chip. Easy Peasy!

Note that to really experience these gains, you must install the 2 other important upgrades to your E30: Air Intake and Exhaust, both covered here!

  1. AIR INTAKE

The most popular, easiest to install, and cheapest mod is probably the cold-air free flow intake. And “Cold-Air” is the key word here. Commonly, people throw on a cheap free flow air filter but neglect to realize that it’s sucking in hot air from the engine bay! So if you’re going to do this mod, you want to ensure that you block the air intake from the hot engine air.

air intake

K&N is the most ubiquitous household name when it comes to free flow intakes. And lucky for the e30 enthusiast, they even offer a cold-air version as well!

This mod alone does not increase horsepower. But combined with a chip, and you now have an engine that wants to breathe, and actually, now can breathe!

  1. POLYURETHANE BUSHING UPGRADE

Next, those old tired rubber bushings got to go! For the avid auto enthusiast, poly bushings are the new norm and dramatically improve handling and responsiveness. The best part? You can easily install this yourself without any special pullers or presses! Choose from 80A (soft), 95A (harder, race), or for the extreme Delrin. More information will be in a future blog, but see below for a sneak preview to choose what’s right for you. Best of all, there’s a lifetime warranty on the bushings!

80A – Perfect for the OEM Feel with a bit of responsiveness. Rest assured that there is no compromise for comfort here, yet your E30 will turn, brake, and accelerate much more precisely and predictively.

95A – Recommended for motor swaps, very aggressive drivers, or otherwise track use. These further increase the responsiveness of all aspects of driving and provide the ability to have a more spirited driving experience.

Delrin – Harder than 95A and one step below solid mounts. These will allow virtually no play between your engine, transmission, and subframes. The feel will be a very sporty feel recommended for race applications.

Garagistic offers Polyurethane Bushings in a wide variety of applications including drivetrain, differential, trailing arm, control arm, and rear subframe bushings.

  1. EXHAUST

The options here are endless, including free-flow headers, catalytic converters, removal of resonators, or replacement of the heavy stock muffler with a light aftermarket. No matter what, you’re saving weight, which increases performance.

So let’s keep it simple for now: Replace that heavy rusty muffler with a free flow supersprint, ansa, tri-flo, or MagnaFlow, Remus, Scorpion…etc. You can get a cat-back exhaust system, which includes the pre-bent tubing with fittings, clamps, and hangers. Here is an example of MagnaFlow’s Cat-Back system.

These systems range in the price of $1200 (complete cat-back system) to as little as $140 (just a muffler). The cheaper you go, the more aftermarket modifications and welding you’ll have to do, so if you’re creative and resourceful, you can get better sound and more power for a fraction of the cost of a complete bolt-on system!

Exhaust

Do not get FlowMaster. They do not mate well to the exhaust note of these high-revving engines. The glass-packed (fiberglass) are the way to go for an E30 Mod.

If you decide to go with aftermarket headers, steer clear of the ebay OBX headers. Even though they are cheap, they have had confirmed fitment issues, they use inferior thin walled steel, and have been known to corrode. But most of all, they are not equal length headers and have no testing to back up the claims of increased power. In fact, you will likely decrease your power!

When it comes to headers, stick to the brand names… headers are one part of a tuned system and they do show more power with a chip, because they provide a tuned back-pressure to extract exhaust gasses, creating negative pressure on the exhaust stroke.

  1. WHEELS/TIRES

This is an incredibly broad topic, and will be discussed in further dedicated blog posts.  But to keep things simple, here are the things you need to know about the E30.

  • 57.1 – This is the centerbore of the E30. If you get aftermarket wheels with a different centerbore, you will need hubcentric spacers
  • 4x100mm – This is the lug pattern for the E30 and is a must-have when fitting new wheels, unless you have a 5 lug.
  • Low Offset – Anything above +20mm is likely too high and you’ll have rubbing issues and/or need spacers.
  • Diameter/Width – 15″ diameter is appropriate for an E30. Many go with 16″ and if you want more extreme, you can go 17″. 18″ and up is not recommended.

Tires is just as broad a topic and there are certainly tradeoffs no matter what you decide to go with. Some questions you must ask yourself before buying tires is:

Will I be racing? I might want a softer rubber compound.

Am I looking for max gas mileage? Then an all-season with a 400AA treadwear is most appropriate.

…etc.
Remember that no matter what wheel/tire combo you go with, you will be sacrificing one aspect for another. Larger wheel/tire combos rob the car of more energy as they are heavier and have more mass to spin further away from the center of rotation whereas smaller wheel/tire combos have less rotational inertia and can effectively increase the acceleration of the car. 17’s just look cool though!

At the end of the day, it all comes down to your personal agenda for use and your preference.

  1. REINFORCEMENT

With more power and stiffened suspension comes an increased need to provide additional bracing. Suspension reinforcements are not only popular, but they’re an indication that you not only care about going fast, but doing so reliably and safely. Garagistic offers a wide array of subframe reinforcement kits for both the front subframe, the rear subframe, both, and strut bars.  You can either weld the kit on your own subframe or send your subframe to get completely welded for you! For those looking for some insane support underneath, check out the X-Brace, race proven reliability and performance.

A new product that just came out to further reinforce the flimsy stock E30 front subframe is the clever front control arm ball joint reinforcements. These are critical for race applications and ensure that your E30 is always on the straight and narrow. Installation is easy and accessible, so give it a try!

Reinforcement

  1. COOLING UPGRADES

There are a couple of upgrades that can help your engine run cooler, especially in those hot summer months waiting in traffic! Stock thermostats close at 99C (or 210F). But you can adapt a plug and play thermostat that opens at a lower temperature to allow the hot coolant to get to the radiator earlier. Here is an example of an 92C, 80C, or even as low as 71C thermostat. These can be found many places in the $20-$30 range.

Tstat

If that’s not enough, you can always turn those cooling fans on earlier with a lower temp fan switch, mounted conveniently in the radiator itself. It monitors the temperature of the coolant and activates both the low and/or the high speed radiator fans to activate the cooling earlier as well. Again, stock switches open at 99C, so having a switch that opens at 80C/88C (3 prong below), or 82 degree (2 prong for older models) can help immensely in keeping your M10, M20, or M42 cool

Be aware that there is a shortcoming to earlier opening thermostats and switches: The lower degree thermostats open at lower temperatures for better cooling but can reduce heater output when outside temperature is colder.

fan switch

 

  1. SHORT SHIFT KIT

One of the best ways to improve the feel is to upgrade one of the most widely used components on your car: the shifter! Changing the length of rod below the cup actually, allows a shorter shift throw and a notchier feel. As a result is one heck of an improved driving experience with every-single-shift. Driving becomes sportier and more connected with the road than you ever have before. The most popular mod here is the Z3 Shifter, which positions the shifter perfectly in the E30 and provides the sporty feel that all Z3 owners currently enjoy. While you’re at it, you might as well upgrade the bushings for your shifter assembly. More detailed technical information about the dynamics of a short shift kit is in an upcoming blog, so stay tuned!

SSK

  1. MOTOR SWAPS

This will not only be covered in many more detailed blog posts, it will be covered in so much detail that you’ll be considered an expert in the subject yourself! Garagistic specializes in many engine swaps including E30 M30, M60, M62/S62, and LS1. There are many parts supplied by Garagistic to get you started on the right foot!

Motorswaps1

Motorswaps2

The list goes ON!

Want to be the ultimate specialist in your community? Purchase the E30 M30, M60 and M62/S62 write-ups with hundreds of annotated pages, tables, diagrams, and wiring schematics showing you how to get your swap done, from start to finish. These can be found at our partner, www.macalent.com for your convenience. All swap parts are supported and supplied by Garagistic to get your swap started, moving, and completed so you can move on to the next big project!

Visit the Garagistic Store for all of your favorite BMW E30, E36, E46 Parts and much much more!

E30 Differential How-To for Beginners

BMW E30 differentials are essentially the gearing module that connects the input driveshaft to each of the rear wheels. Some differential are “open” and some are “limited slip” or “posi-traction”. The primary difference being the ability of both wheels to spin in a slip event. An open differential is oftentimes cheaper because it is not designed to maintain traction of both rear wheels. You can most commonly experiment with this in the snow. One wheel spins and the other does nothing. In limited slip, at least 25% of the force will be distributed to the most heavily loaded wheel, or the wheel that normally would not spin, now gets 25% of the torque.

But there are clutch discs inside of the limited slip mechanism, and they do wear out. So a hard driven 25% diff may only have 5% lock. Which is why you should stay tuned for a more detailed blog about changing LSD clutch packs!

From the outside, you can easily denote a limited slip differential by 2 means: The tag on the differential has an S before the ratio. Example: S2.93, S3.73. You will also find an “S” stamped on the top of the differential. Be careful. The tags can always be removed and added to an open differential as a scam. However, the stamps cannot be added, so this is something to definitely check for.

LSD Tags stamps

The “ratio” is that of the number of rotations of the input to the number of rotations of the output. Most BMW E30 Differentials vary from 2.79 and up to 4.45. That means that the input shafts spin 2.79 times for each spin of the output shafts! With the transmission gear and vehicle’s speed being constant, the higher the differential ratio, the higher your engine will rev. A lot of racers experiment with the perfect ratio as to get the most useful horsepower during race day. The good thing is that you are not limited to simply E30 ratios! You can use the E23 7 Series, E24 6 Series, or most commonly, the E28 5 Series.

diff ratios

Just note that there is a bit more work that needs to be done if you are swapping from a different model. You must swap the rear cover and the output shafts, but this is easy. The output shafts remove very easily with a wooden stick, pry them out at the flanges. They should just pop right out!

You have 2 versions: small case and large case. Small case has a ring gear diameter of 168mm and the large case has a diameter of 188mm. The large case differential has been proven to handle upwards of 500ft-lb. See below for a common comparison between small case (left) and large case (right) E30 differentials. You almost never want a small case. The two sizes are 100% interchangeable in the E30 subframe.

small medium case

Do you already have big power and want to provide additional bracing? Or perhaps want a sportier feel – – Something more engaging for the driving experience?

Well, Garagistic has you covered!

Feel free to browse store.garagistic.com and check out their selection of 80A, 95A, or delrin differential bushings. Installation is easy and can be done with basic hand tools!

diff bushing

If you’re looking for supporting more power, click below for the installation video on the ONE OF A KIND IN THIS INDUSTRY second differential mount. This is a must for any >250bhp upgrade to your E30. Installation is, well….. see for yourself!

youtube diff mount 2

To complement that power, strengthening your subframe is key and can also be sourced right here. Garagistic offers a simple, easy to weld kit to strengthen your subframe to where the differential mounts. 4 holes, all can be strengthened. Examples time and time again on the track have shown this area to be particularly susceptible to weakening during hard acceleration. With additional bracketry, this problem is now dissolved.

differential reinforcement

You can certainly swap your own gearing. But if you do, you must take note on what ratio differential you currently have and what ratio gears you WANT to go to.

The rule for swapping gearsets is that you have 2 ranges. The low gears (3.07 and below) and high gears (anything higher than 3.07). To make this easy, you must have the gearset for the differential that you want to change.

Example: You currently have a 3.25 differential and want to swap to 3.46. You can easily acquire a  3.46 gearset and swap into your 3.25 by exchanging the pinion and the input gears. This is because both are above the 3.07 ratio.

Same goes for the lower gears. Stay within the range.

If you decide to cross the 3.07 threshold with swapping gearsets, you must use 2 extra shims that are necessary to make up for the geometry of the gearset fitment. Without the shims (or removing them), you will certainly have fitment issues and have premature failure, noises, or vibration.

 

Thanks for reading!