Guide to Basic Set Up Blocking Procedure - Tech Talk
Frank Galusha shows the step-by-step blocking procedure to set up your Micro Sprint race car. First, remove the arms, chain and torsion bars. Grease the torsion bars with a light film and reinstall. Make sure there is no bind and the bar is loose.
Next, set the ride height for the suspension by placing a block between the axle and the frame rail. After that is complete, you will set the suspension. Put the arms back on the torsion bar, leaving a gap at least the size of a quarter between. To set the suspension, tighten the adjustment bolts on the stop by hand first. Frank considering zero preload to be when the bolt it tight by hand. Anything you do in addition to that is pre-load. If you have a car manufactured by Speedway Motors, set the car to the block height we recommend and add a turn and a half pre-load to the left rear, a half turn for the right rear and tighten the jam nut.
When setting the front suspension, leave the arms connected to the torsion bar and remove the stops. Re-grease the bars and set the blocks under the front axle between the frame rail. Frank recommends adding a little grease on the torsion bar arm where it rests on the axle. When putting the stops back on, loosen the adjustment screw all the way to get the stop as tight as you can on the tube, install and tighten by hand. Whatever side you want to preload, the stop is on the opposite side.
All of the settings can vary track to track. Adjustments can be made before you head to the track or during an event. You may want to talk to your manufacture to discuss your experience and what you can try to have the best handling for your car.
Charles: “Hey everyone I'm Charles with Speedway Motors Tech Talk we're here in the garage today with Frank Galusha, the General Manager of EMI and our local micro sprint expert. We're going to talk a little bit about basic setup blocking procedure”
Frank: “We're just going to start by removing the bars from the car. One of the most important things is to clean them and lubricate them. So, first, obviously, we're going to disconnect our arms. You'll see I've already got them disconnected. Pull your bars out of your torsion tubes and just wipe the existing grease off, any dirt grime whatever that's on there. Just get them good and wiped down clean. Then, once we get them clean, we're just going to re-grease them and lubricate them.”
Charles: “And this is all after you take the chain, the sprocket, everything off. You probably wouldn’t want that on there when you're blocking the car?”
Frank: “Yeah, this procedure happens with the chain off the car. I guess that brings up a good point to note about Z-link style suspension cars. For those of you who are unfamiliar with what a Z-link suspension is, it's literally a rear end with one radius rod to the top of the birdcage and then your torsion arm, to the torsion bar, so just two connection points. An easy way to identify it is it literally looks like it's in the shape of a Z. Anyways, we're going to grease these up.”
Charles: “Any special kind of grease you're going use? High heat, low heat, multi-purpose?”
Frank: “Honestly my favorite to use is just a white lithium grease. It's super lightweight, it's slick, it's easy to use, it's easy to clean off. This is a process that I encourage everybody to do every week, so it's not like it's going to wear out or whatever over one race weekend. The only part you really need to grease up is just right around where the bar rides in the bushing.”
Charles: “Now I know some people like to grease the whole bars, is there any advantage to that at all?”
Frank: “It won't make a difference if you grease the whole bar. The greater percentage of the torsion bar doesn't touch anything, so the grease is literally pointless in those areas. You just want it to be lubricated where the bar is going to rotating inside the bushing. Once you get it re-lubricated, slide it back in your torsion tubes. Before I put this one back in, I want you to notice our adjustment bolt on the stop. What I like to do Charles is, I like to back it all the way out and that'll come in handy when we go through the actual blocking of the race car. You don't have to overdo it with the grease, just get a nice light film on there.
"Another thing that's important. When you put the bars in the tubes, make sure that they spin freely in the bushings. If there’s any bind, there could mean one or two things. One, you may just need to ream the bushings. Two, it could be an indication that there may be a bent tube or something. If they were free the week before and all of a sudden, they're tight this week when you're doing your blocking; you might start looking at some other things because these need to be able to rotate free of binds. You don't want them loose, but free is a good thing."
Frank: "So, what I want to show you here Charles; is this is exactly why we call it blocking. What we're doing is we're setting the ride height for the suspension. So, the way we do that is, we put a block between the axle and the frame rail, and we're just kind of pre-determining the height at which the axle sits when we're setting the suspension.”
Charles: “Can you use just like a wooden block, obviously, are there different types of blocks?”
Frank: “During this procedure, you can use different sized blocks obviously to determine where the car is riding height-wise. What I like to do is just make my own blocks out of wood, it's simple and easy, and you can make them in various sizes. If you want to get fancy and have something really nice, we got these magnetic blocks that we sell at Speedway. Obviously they're adjustable, so you can get them set to different heights and then the bottom is magnetic, so it sticks to the frame. So, it actually helps aid in the process."
"Now that we've got bars cleaned up lubricated put back in the tubes. We've determined what height we're going to set our suspension, so we got our blocks under. Now we just got to put everything back together and set the suspension. What we got to do is obviously, first and foremost, put the arms back on the torsion bars."
"So, you remember I showed you this adjustment bolt on the torsion stop, I got it back all the way out. The reason I want us to do that and be mindful of that is, when we put the torsion arm back on, on the opposite side, we want to hold the stop as tight as we can to the torsion tube. That way we've got plenty of bolt to thread back in, and we don't have a bunch of it exposed between the torsion tube and the torsion stop."
"What I also try to do Charles is, I try to keep a minimum of a quarter, you know like the coin width of gap, between the torsion tube itself and the arm when I put it on because, when the bar twists as the suspensions working, it'll actually draw it again. It'll draw together and so by leaving a gap there, it prevents any binding from the stop or the arm rubbing up against the tubes. Keep a gap there, that's super important I like to go with the maximum gap. Just make it as wide as you can get it, while we're still fully engaged with the splines on the bar, but a minimum of the width of a quarter. So, we'll get that tight on there and then the same thing, so you guys can see at home what we're doing on the right side. I'm going to put this left sidearm on, keep the stop tight to the bottom of the tube or as close as you can while you're putting this on. The last thing we do now, we're literally setting the suspension and how we do that is we're going to tighten down these adjustment bolts in the stop.”
Charles: “Put a little tension on the bar?”
Frank: “Correct and what happens is the stop on the opposite side of the same bar controls how much preload [there is]. If you're not using our cars, your manufacturer may have suggested preloads or blocking heights to use for your race car. Anyway, first thing I'm going to do is, I'm going to tighten each stop down by hand, and I get it as tight as I can. I use a rag to help me with grip strength just because those 5/16 bolts are kind of hard to get a hold of. Zero preload, in my opinion, is when you get this as tight as you can by hand. So we'll get both sides as tight as you can by hand. Then anything you do in addition to that is what's called your preload. What I'm going to say is with our cars, off of our block heights that we recommend, we're going to put a turn and a half preload in the left rear. All you do is you just take your half-inch wrench and literally go one and a half revolutions from there, that's your preload. Once you get that, tighten the stop.”
Charles: “What about the right rear?”
Frank: “The right rear, I like to start at about a half turn. Once again, your manufacturer may recommend something different but literally same thing. Just put that half a revolution in there, tighten the jam nut on the stop. Now your rear suspension is set.”
Charles: “So we're at the front end, we've got the rear done. It looks like the bars are out and greased, ready to go. What do we do differently upfront, over the rear?”
Frank: “Good question Charles. It's pretty much the same procedure. One thing you'll notice different about the way I'm doing the front versus the rear is on the rear we left the torsion stops connected to the torsion bar. On the front, I leave the arms connected to the bar. From front to rear, it's just what's easiest given which end you're on. This is what I choose to do, it's not right or wrong. You can do either way, but this is the way I prefer to do it."
Frank: "So anyways, got the bars greased back up. We're going to do the same thing, set the blocks between the frame rail and the front axle. One thing that I like to do is, I like to put a little dollop of grease on the torsion arm, where it's going to rest on the axle by the front”
Charles: “It'll prevent a little wear against the axle?”
Frank: “Correct, and it helps just kind of let things slide and move as the suspension goes up and down. That's one thing to maybe do when you're doing the front end. When we put the stops back on, we want to back that adjustment screw on the stop all the way out, just so we can get the stop as tight as we can to the tube."
Frank: "So, we'll put the stops back on here. Once again get them as close to the tube as you can. I get the adjustment screw as tight as I can by hand. Whichever side you want to preload the stop for, that corresponding corner is on the opposite corner of the car. Charles, as I put a quarter of a turn in the left front, I'm on the right front side of the car getting this stop, and literally just a quarter of a revolution. There's my preload; tighten the jam nut. All these settings can vary from track to track. Obviously by adjusting these stops, whether it be before your other races or throughout a race event. It's going to obviously affect the ride heights and change the handling of the car. These are some things that you may want to discuss with your chassis manufacturer about making changes, and when it might be a good opportunity to try some different things based on what you're experiencing. Maybe handling issues, or what have you.”
Charles: “So, this isn't something that you're going to do only in the shop. This is something you can do at the track if you need to, or if you want to try something different in the middle of the race basically?”
Frank: “Correct. Adjusting those adjuster screws is definitely going to be something that you could do while at the event between races to change the handling of the race car.”
Charles: “Alright, well thank you so much for showing us all this awesome stuff today and thank you guys for watching”