This week ill be tackling the clutch and flywheel install process, and hopefully showing you some tips and tricks along the way. Anytime you get a new (used) engine or have to pull your engine out for any reason, its best practice to change the clutch and the flywheel (or at least get the flywheel resurfaced) It seems like a lot of people tend to just reuse the clutch the engine came with, but for me I figure while its out it would be best to just replace it. Replacing the clutch is very easy to do when the motor is already out of the car, and I don’t want to put everything in and get the car running only to find out that the clutch is bad. I am especially particular when it comes to any part of the shifting system on the car (clutch master, slave cylinder, linkage, short shifter, or clutch) I feel like just because you think the car shifts smoothly, that doesn’t mean its not actually just taxing the synchros and wearing out the trans quicker. The synchros are there to help “synchronize” the gears as you shift and I would never want a good trans have a shortened life or wear out quick just due to negligence on my part. This is why i’m always making sure that I’ve got good quality parts when it comes to transmission shifting. I may be over thinking it, but what if I got a slave cylinder or master cylinder at autozone and it doesn’t hold as much pressure as an OEM part would? What if that would cause my trans to wear out quicker? I know, I know… I’m probably thinking too much into it, but quite honestly I just feel better knowing that my whole shifting system is up to par. This way, I will have no doubt in the back of my mind that anything will be causing premature wear on my transmission. OK! there, now you know about how OCD I am when it comes to my stuff. Let’s be honest though, it costs a lot of money for these Engines/Transmission, and I cant afford to keep buying new ones.
Starting out, most of you know that i’m in the process of doing a B16 swap in my 4 door. For the new readers that aren’t aware, let me give you a little back story. I was tracking my 4 door for almost 2 year with my d16Y8 and I finally reached a point in my driving where I felt like I needed to get a limited slip trans. I was beginning to experience some uneven tire ware due to only spinning one wheel on tight turns, and getting a SOHC LSD trans was a very hard to come by thing. Building one would be almost the cost of getting a B16 (well a full SOHC trans build) so this lead me to thinking about getting a B series. There a lots of options for a LSD B series trans and with all B series being a helical LSD, this means that while not being the best possible LSD they will pretty much last forever (unless you have crazy power and are jumping curbs on the track. That shock can shatter the diff) but I got a B16, so i’m not going to have power anyways (LOL). Yes, a 1 way clutch pack LSD would be the best set up, but in terms of reliability and low maintenance the helical is a good choice. Maybe two years form now ill upgrade, but I was tracking the SOHC with no LSD so any LSD is going to be better.
When deciding on what trans to get, I had to keep in mind that I was going to drive this car to events up to 300 miles from my house. This meant that I wanted to make sure I kept a 4.40 FD. Of course, getting the holy grail of stock transmissions (98-01 Type R with a 4.78 FD) would have been better in terms of on track performance but not as good when it comes to freeway driving. I chose to go with a 97 type R trans because this will offer me the 4.40 FD that I was looking for, but still have a B16 ratio 4th and 5th so it remains peppy since I do not have the added torque of the 1.8 liter B18c.
Below are the links to the different parts of the B16a build thus far.
Oil pan baffle install: https://functiontheory.com/2020/03/how-to-b-series-weld-in-oil-pan-baffle/
Complete B16 refresh: https://functiontheory.com/2020/04/b16a-refresh/
B16A valve adjustment: https://functiontheory.com/2020/04/b16a-valve-adjustment/
On to the Clutch/Flywheel Install process:
Replacing the rear main seal is another one of those good preventative maintenance things. It’s cheap (even for an OEM one), and its super easy to do. Why would you not switch this out while its easily accessible. If this seal is bad, not only will it leak, but it can cause oil to get on your clutch/flywheel. This will cause slippage, and will burn up your clutch real quick. So do yourself a favor and just replace the seal.
Below is the seal.
I have heard that using a paint can opener works really well for this. I just use a small pair of needle nose pliers and inset one side into the seal (there is a metal ring in the seal that will crush and allow you to scoop it out) Be careful to not scar up the crankshaft, this could potentially cause the new seal to not seal correctly. There is no need to loosen any nuts or bolts, just carefully pry it out.
Once the seal is removed, the bottom end of the engine is exposed. Be careful to not get any dirt/debris in it. Carefully wipe down the area where the new seal will be installed in, making sure it is dry, and clean. You don’t want any dirt in there.
Here is the part number for the new seal.
The new seal will come pre greased on the inside, but to help with it slide in a little easier spread a very thin layer around the outside.
Evenly press in the new seal by hand (It will only go so far. It only needs to sit flush, as seen below) Then take the old seal and flip it around backwards, place it against the new seal and gently tap in a circular motion to get it to seat all the way in. DO NOT hit the new seal with the hammer, only hammer on the old seal. Also make sure when hammering it in that it is going in evenly.
Below is what the new seal will look like when installed.
Now on to the clutch and flywheel:
There are quite a lot of different opinions and theories when it comes to clutch selection and what weight flywheel to get. Let me share with you my two cents and experiences over the years. Starting of with my clutch selection, I chose to go with an Exedy stage one full face disc sprung clutch. It’s best to choose a clutch that is made form organic materials. I also always choose to run a sprung clutch, this will just help to reduce the shock in the driver train. There really isn’t a need for an unsprung on a daily/track car set up. Plus having the sprung will help you stay under control on some of those botched down shifts going into “turn 1”. I used to run unsprung clutches, but after having axles seized into half shafts, hubs, and ripping motor mounts from chassis its just easier to have a sprung clutch.
For the flywheel, It should be a balanced weight. Not too light, and not too heavy. Too light of a flywheel can cause issues like:
- Idle surge (as the engine struggles to adjust itself)
- Easier to stall
- Loss of torque
- Harder to shift smooth since the engine will loose RPM so quickly between gears
- There is also a certain point at which the momentum of the flywheel isn’t enough to keep the motor revving higher and this will start to rob power.
Too heavy of a flywheel can have its set backs too.
- More engine power is needed to set off and accelerate (low end is affected)
- lethargic engine response
- Take too long to get into power band
Its fun to have a lightened flywheel because it really brings the car to life, makes it peppy and fun to drive. But the flip side is how tough it is to drive a daily with a really light flywheel. There is really a lot of personal preference when it comes to choosing a good clutch and flywheel combo. Just remember that you cant really go wrong if you follow the clutch manufactures recommended horsepower and toque rating for each clutch stage. As for flywheel’s something in the middle (say 4-8 lbs less than stock) will be a good balance of drive ability and performance. Please also keep in mind my suggestions are for people with 400-450hp or less. Of course there are lots of other variables that go into the selection process: N/A, Nitrous, Turbo, supercharged. They can all drastically change the characteristics of the engine and its power band.
Completely contradicting myself, I chose to try and get the lightest possible flywheel that I could find. My car is only going to be used for fun, and is no longer my daily. I also feel like my overall plan for the car is to not worry about making peak power, rather focus on allowing it to respond quickly to any throttle modulations on track.
Below you can see what I chose to go with. I also decided on ARP flywheel bolts just because I needed flywheel bolts and the cost was pretty close to what the OEM bolts would have been. Besides its nice having that extra peace of mind.
Starting with the flywheel, take the new pilot bushing and press it in. I chose to use a socket that matched the exact size of the bearing and tapped it in with a hammer. Now that the pilot bearing is in, its time to crack open the new ARP flywheel bolts and begin to bolt the flywheel on. Make sure you use loctite.
You’ll notice above it gives the stock oem flywheel bolt torque specs of 87 lb/ft. However, the ARP ones call for 95 lb/ft. Above you’ll also notice the “proper tool” to keep the engine from spinning around as you tighten the flywheel bolts. Below you can see my improvised tool. I thread in one clutch bolt, a trans bolt, then use a wrench to stop the movement of the flywheel. Make sure you use a 12 point socket to tighten the flywheel bolts. both stock and aftermarket ones are 12 points. If you use a 6 point socket it will strip out the 12 point bolt head.
Now make sure you spray brake cleaner all over the bolts to remove any of the assembly lube, and the spray the flywheel surface to get all the oil off they use to protect the flywheel during shipping and storage. Once the flywheel is wiped clean don’t touch it. the grease and oils from your hands and fingers can cause issues (heat spots, slippage, and not properly being broke in)
Now on to the clutch. Just as you did for the flywheel, spray brake cleaner on the clutch surface to clean off all grease/oil and make sure not to touch it with you greasy hands or fingers once its clean. DO NOT spray the clutch disc.
There are three alignment pins in the flywheel that the align the clutch pressure plate. Usually ill have the clutch alignment tool (black plastic piece that comes with the kit that resembles an output shaft) inserted into the pilot bearing (as seen below) this will hold the clutch disc in place while you spin the pressure plate around till the three pins fit properly into it. The pressure plate will only fit one way, if the orientation is wrong it will not match up with all the pins. (this will make more sense once you’re doing it) Basically if you cant get the three pins to line up, keep rotating it around till you correctly line up all three (its not the wrong clutch) Be sure to grease the splines of the clutch disc, usually aftermarket clutch kits will come with their own grease. This is to be applied to prevent binding of the clutch disc and it slides on the splines of the output shaft.
See above, the orientation of the disc, and how the alignment tool slide through it and into the pilot bearing. This will allow you to use both hand to spin the pressure plate around till you can correctly line up all three pins on the flywheel. (side note, if your flywheel doesn’t come with the pins installed, you simply tap them in with a hammer.)
The ol’ wrench trick wont work here. This time around I use a large pry bar, below you can see how I have it wedged against the bolt holding the engine on the stand and the floor. There are specific tools for this but the torque specs are so little that usually you can just figure out a way. 19 lb/ft.
Also note the correct order to tighten the clutch bolts in. (see below) Another thing to note is that these are 12 point bolts so you must use a 12 point socket to tighten them. If you use a regular 6 point socket you will strip them out.
Below is the completely installed clutch.
Now its time to prep the trans.
Start by removing the old throw out bearing. This is another one of those parts that should be replaced every time you have the trans off (unless you’re pulling your trans off every week) A new throw out bearing isn’t much money and it should come in your clutch kit you purchase.
Next pop the clutch fork out too. It’s held in with a spring clip around the pivot ball, but you should be able to just wiggle it off by hand.
you will now completely clean the pivot ball, taking all grease off it.
Then completely clean the area where the throw out bearing will slide on
now completely clean all the grease of the fork and the spring clip.
I use this Honda super hi temp grease, and that’s whats recommended. If you can’t get your hands on this stuff, the next best thing will be any sort of hi temp grease.
Spread a thin layer of grease on the shaft. this will allow the throw out bearing to slide freely with out binding.
Spread grease on the pivot ball
Pack some grease into the fork too. This will help stop squeaks from happening.
New throw out bearing and fork reinstalled. just make sure the spring clip snaps around the pivot ball.
At this point you can now mate the trans to the engine. Usually it’s some what difficult to do this especially by your self. I use this nifty Vein engine stand and it makes life a lot easier. (you can check them out on Instagram @veinenginestands)
It’s now almost time so slap this bad boy in, but you’ll have to come back next week to read all about that. Thanks for following along through the build process thus far. My hope is that as I break down every step of the process you will not only learn how to do these things on your own, but you will get the confidence to try and do this on your own. As always, if you have any questions feel free to reach out to me via email at Billy@functiontheory.com, Instagram @Functiontheory, or just comment down below.