SFI fluid damper for 4.0

[Plechtan]

Does anybody know of a Fluid damper available for the 4.0? or maybe one that could be modified for the 4.0. I would prefer one that is SFI approved.

[yuppiexj]

Ditto...

I would think that any internally balanced damper would work. (i.e. Not BBC)
As long as snout length, inside diameter, outside diameter (for oil seal) and keyway match I see it working
There is the issue of the OE damper having an integrated pulley, most others that have fluidampers available do not.

I would pay up to 500 for a direct fit 4.0 damper that won't separate or spit out the rubber

[Plechtan]

Well i did not find a fluid damper, but i did find a Sfi rated race unit. Here is a link http://www.atiperformanceproducts.com/p ... r_tech.htm

It is made by a company called ATI. They say it is a custom unit, but they have made them before, it is Drawing Number SK008 Cost about $600.00 and is about 3 months delivery. Price could be reduced if a quanity of units are ordered. I'M in, anybody else need one?

[Plechtan]

Oh! I forgot, it does have a 6 grove pully on it.

[Alex22]

ATI's stuff is top quality and If they made one in my price range I would defiantly go for it. The problem with making a damper from another engine work on the jeep crankshaft is that each engine produces its own harmonic and the dampers are designed to work at that frequency. The RPM, frequency and amplitude of the harmonic differs from engine to engine (not sure how much) and it also depends on how well the rotating assembly is balanced.
How much stuff are you running off that front pulley?

~Alex

[Plechtan]

At the moment I have not purchased one, but my plan is to only run the alternator. When it was talking to the guy at ATI he said that the drawing also showed a timing pully on the front of the damper. Could have been for a dry sump setup. ATI did engineer it for the 4.0 and did make it for sombody ( the tech did not know who). The ATI stuff is used in Nascar and Drag racing, it is a quality part and was made with an integral 6 grove pully. I will be ordering one, Harmonics are one of the biggest problems on the 4.0 when you are trying to get some RPM's out of it.

[Plechtan]

I received the damper from ATI, Was I surprised, the damper does have a 5 grove pulley for a serpentine belt, but the pulley sits 3/8 of an inch further away from the timing chain cover Hub is very long and sticks out the front of the damper 1.5" When i ordered it they said that it had a provision for a fuel pr oil pump drive. It looks like you would make a shaft the same size as the crank and insert it from the front , then put the bolt through the middle. I will modify the hub to move it a little closer. I am using a 258 Crank, and will make the hub work with the 64mm snout. The Damper does have 3 bolts on the front to secure a blower drive or pump drive mandrel.

The ATi shell assembly is part # 7071 This is a standard part available form Summit racing or Jegs. You could just purchase this and make your own hub.

nothing is ever easy

[John]

Thanks for the update, Keep us posted on the damper project. May not be new arena, but not many have tried this, I haven't. Good info. I tried to find ATI 7071 without much success, but did find the 917071 in several places?
John

[Plechtan]

You are correct, all ATI damper numbers start with 91, so the correct number is 917071.

The ATI damper has a part that sticks back .090 further on the back than the Jeep damper, so the belt will be .090 more forward than the stock location. I don't think this will cause a problem, the belts are pretty forgining.

Some people think that the ATI unit is not much different than a stock damper, but because it has 2 sets of rubber, it can control harmonics. the o rings can be changed to tune the damper.

[John]

A lot of the people that dismiss them are running the OEM and haven't tried anything else.
John

[Plechtan]

I got my ATI damper a while ago, it was a bit of a suprise, it did not put the pulley in the stock location. It stuck out about 3/8" too far. I modified the hub to get it as close to the stock location as possible, bit it is still out about .090. The hub extends about .8125 in front of the pulley, It looks like this is so you can insert a shaft in from the front to drive an oil pump or fuel pump or maybe a supercharger. The Damper is generic and sold mostly for use on chevy small block motors. A hub is installed in the damper to make it work for a specific application. the Damper is available from summit for less than $400.00 but if you purchase it with the hub from ATI it is more like $575.00

I have purchased an oil pump drive from Peterson that bolts on the front of the damper. The only problem is the .8125 hub sticking out, I will machine it off and install a trigger ring between the pump drive and the damper. The damper has 9 holes in it, 6 holes are counter bored and are used to hold the damper to the hub. the other 3 holes are to secure a trigger ring or pump drive, or even another pulley on the front. Here are some pictures:

ati-1.gif

ati_2.gif

ati_3.gif

[Plechtan]

OK more pic's

ati_4.gif

ati_5.gif

ati_.gif

[cavaliers1323]

Thanx for the pics/info! Keep us updated! What oil pump are you going to run?

[Plechtan]

I went with an oil pump and spline drive from Peterson http://www.petersonfluidsys.com They have both wet and dry sump pumps. I went with a wet sump to save money.

I will have to cut off the part of the hub that sticks out on the front of the balancer. The spline drive bolts flat on the front of the damper. In my application i will have a trigger wheel in between the damper ant the pulley drive. I will post pictures when i get it done.

Because the Hub from ATI required extensive modifications, i made a drawing of the final hub. If there is any interest i could have a few made up.

[Mgardiner1]

Peter, what other options for dampers were you looking at? anything "aftermarket" that is direct bolt on? i'm looking to replace my stock one, and if i can "upgrade" without big bucks and machine work, i'd like to.