Monotube vs. Twin-tube Shocks

[Mod77L]

What is the advantage of the low-pressure, base-valve, monotube shock vs a twin-tube of the same valving when on the slick? It used to be that you ran gas shocks on the tack or rough, and twin-tubes on the slick. What changed, and why?

Are they best suited to be run together (all gas, or all twin-tube) or is there an advantage to having a certain type on a certain corner?

Is it just a way to get you to buy the $250-$350 monotube vs the $150-$180 twin-tube?

FWIW: I run IMCA rules, so no schrader valve (no pressure adjustments in the pits).

[charcoal01]

I think the thing that the basevalves are supposed to do the best is feel like oil but act like gas. So if you race a track that normally stays pretty slick but sometimes develops small holes or a little bit of a rough cushion, you won't have to worry about shock fade with the basevalve like you would if you were running the oil. Also, I think the gas helps control cavitation in shocks with rebound numbers like most of us are running on the rf now days. Feel free to correct me if I'm wrong.

[hammond motorsports]

the mono-tube shock doesnt fade like a twin tube(twin tube is a good short race shock) but the big deal is the piston design and what you can do to the piston .Also the size of the pistons .Integra twin tube is 1.185 and the mono piston 1.620 The mono tube does not have a gas bag to go bad .If you would like to talk more about this just give me a call 563 659 1153 .I build the Integra shocks here at my shop. Thanks Dave

[7uptruckracer]

A good monotube doesn't get as hot, and they have a high frequency piston with a base valve so you don't have to run higher gas pressures to prevent cavatation/aeration of the oil so you get more feel then a high shaft pressure. If you run short races on smoother tracks then you might be ok with a twin tube, but on a late model your not seeing it as much anything more then 25 30 laps on a smooth track is fine on anything rough then can get very hot in minutes and they will wear out fast

[Mod77L]

I guess I've never thought to check the temps of the shocks after I come off of the track. It seems quite obvious that I should do it at least once in a while. I just purchased gas Integras for the RF and LR and will have them on the car for this weekend. (If these work well, I will have them on all corners. I just need to wait for the budget to allow it.) I was worried that they might react a little different than the twin-tubes. It sounds like I should just drive it, lol. One less thing in my head while on the track. Thanks guys.

[7uptruckracer]

You will like the package you are going towards especially in the slick the new monotubes have great feel, are cheaper to rebuild in most cases, and a gas shock on the LR will allow the chassis to hike easier, you don't get shock fade due to aeration and heat. Good Deal tell us how you like them. P.S. pay attention to your shock compression and extension especially on the LR extension Monotubes don't have as much stroke available due to their design so sometimes you have to run extensions on the LR to keep it from topping out. I'd suggest a travel limiter on the LR

[setup479point2]

One thing everyone failed to mention , if a monotube gets a dent in it ,it quits working , as your piston runs on the outside tube . If you are on a limited budget you may want to consider this. Also I know a multiple track champion who uses all twin tube , he's won a ton of races against really good cars. Our BMS we couldn't even run monos on front because of denting problem.

[7uptruckracer]

Get protectors and covers, kept us from getting them minus wrecks!

[hammond motorsports]

with a twin tube you dent the body that will preload the gas bag or brake the gas bag .Just make sure the shock can not get hit by the upper a arm or trailing arm .

[setup479point2]

BMS was built that way , I didn't build it . I should have redone it , but wasn't my car , just helped on setup. Never tried the covers , sounds like a good idea. Twin tube will still go up and down with dent at least. The multiple track champ had access to any shock , tried gas went back to oil and continued winning. I like monos , just saying you don't NEED em'. Just giving the guy another option.

[Mod77L]

Well, the shocks felt good tonight, but due to being spun by a couple different drivers, I didn't finish well. I did notice that the car was more consistent through the race than before. I led a few laps and the car felt good. I'm sold.

[JR. MECHANIC]

Just a little tid bit... Not all mono tubes have high freq pistons. To my knowledge, only ohlins offers that.

[sobe92]

Just a little tid bit... Not all mono tubes have high freq pistons. To my knowledge, only ohlins offers that.

Ohlins, penske, BSB (also has this option for an integra shock) and I believe JRI might offer this as well

[JR. MECHANIC]

Sobe, can you help me out? I went to Penskes site and bsb and couldn't find any info on their high frequency piston. Would you mind posting a link?

[sobe92]

I know bsb has them in the catalog and some info on the bsb mfg facebook page. as far as penske I just know they have some from being in a few penske shocks.

if you would like to know more on the bsb stuff shoot jay a message on facebook. on the penske stuff your best bet is re suspension.

[Dragoon55]

You will like the package you are going towards especially in the slick the new monotubes have great feel, are cheaper to rebuild in most cases, and a gas shock on the LR will allow the chassis to hike easier, you don't get shock fade due to aeration and heat. Good Deal tell us how you like them. P.S. pay attention to your shock compression and extension especially on the LR extension Monotubes don't have as much stroke available due to their design so sometimes you have to run extensions on the LR to keep it from topping out. I'd suggest a travel limiter on the LR One point i have to disagree with is that monotubes don't fade, they do. All shocks fade, all shocks build heat(physics) and all have some degree of cavitation. Now monotubes, due to there higher gas pressure do tend to fade less. Also like some others pointed out monotubes are more susceptible to debris and crash damage since they use the actual body as the pressure cylinder, a dual tube does not. You could take a hammer and dent the side of a dual tube and it would function the same as before. You do the same to a monotube and it is toast. Monotubes are generally more pricey to repair also. You can improve the performance and fade tendency of dual tubes by running a higher quality oil and by taking extra care to get all the air out during assembly. I know all this because I was the production supervisor for Carrera Racing Shocks(Atlanta) from 1998-2004 and we built both dual and monotube shocks as well as double and single adjustable. Knowledge is power and speed.

[Mod77L]

BSB had a facebook post the other day about using "Ohlins style" 3-port piston with and without high-frequency holes for Integra bodied shocks. Not sure if you can get them from Integra with their own high-freq piston or not. This stuff is way beyond my understanding, and probably skill level, lol.