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Hey guess what! Valve spring shims for a mopar 440 fit our heads. The ones I have are 15 thousandths and Im sure you can get other sizes and I bet other shims might work also, just take the little bottom retainer with you to your local speed shop and match em up. 15 thousanths should be good but you can go a little thicker if you want dont go too big cause you dont want them springs to bind. You will need at least 30 thousandths If you are using an old caravan head with caravan valves, caravan retainers/keepers, and quest springs. Do 45 thousandths to add a little pressure to older quest springs.
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  • 2 weeks later...

I have a non jetvalve aftermarket head off a 2.6L lebaron.. It is fairly new, it has the VOID if Removed over heat tabs on it.

What would be the best to do with this head?

Install Quest valves and springs? or use the valves and springs in it?

 

Steven

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If it is indeed a 2.6 head and not a 2.5 use the valves that came with it and use quest springs. if the valves are longer than your quest valves use .030 shims under the springs to get the right installed height add another .030 to older springs to up the pressure a bit (no valve float good).
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  • 3 weeks later...

what you  need to pay attention to is the  spring install'd heigth,, early  quest was 1.6"  caravan  lists at  1.59, the aboslute  lowest you can go is  1.5  with a stock cam, biger cams is less,,

what you  can shim to  will depend on what the  final  install'd heigth  comes up to and what the cam lift is  , so  some befor and after measurements are need'd on each  valve to make  certain they  have  clearance , even  brand new  quest springs are not  strong enougth and need a little  help. idealy the use of the heavy  duty  springs is the best way to go as long as the install;d heigth is close to  the 1.6"

any  shorter and the  pressure gets too much

shims are available in  .015   .030 and  .060

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Regardless if it's early or late valves, the install height is the the same 1.6"

 

The difference in height between the two valve styles is above the retainer.

 

I wouldn'r go adding shims to my springs without checking the pressures first.

 

If you are worried about your springs being too weak, buy new ones from Schneider for $40 shipped.  PN 6610

 

Rich

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whoaaaaa, the height is indeed different! Measured with a micrometer both heads with valves and springs installed the difference was about .030 +or- .05. I measured from the bottom of the top retainers (where the spring touches it) to where the spring touches at the bottom (the bottom retainer that is on the heads) so what I did was got some shims (.070) .030 to make up the difference and .040 to add some pressure (Shelby recommends .060 to get eighty some pounds of installed pressure so I went a conservative .040) Ohh It does not bind either just so every one knows or was wondering! ;D
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I don't know what valves or heads you have, but I measured them both on my new Marnal head.  I bought both styles of valves from Marnal and have both styles of retainers and keepers.  They were both 1.6" on the button.

 

Try measuring the two different valves in the same head and in the same hole to get an accurate comparison.  If one head had a valve job, your install height will change.  That is one reason for having to use shims in the first place.

 

I assume you meant +or-.005".  How did you measure the spring install height with a micrometer?

 

Rich

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I dont know why these valves are different height but they definately are. You can set them side by side and see that they are, install them in the head same thing. It was a dial indicator i used(measures inside and outside dimensions to the thousandth of an inch) I know there is a name for this tool but i forget what it is.(I thought it was micrometer for some reason :-[.) There is no way around it I had to use these shims or I would float the valves way early.If I did not measure the two different valves I would have did alot of work just to take it all apart and do it again. I wish I knew the year caravan that I got the head from, I do know that it was an older one (older style square light front end) but everyone should definately measure b4 puttin anything together. Neither of these heads had valve jobs or anything either.
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Dial Caliper.  That's what I used too.

 

I guess the difference is used vs new.

You did have a difference in the retainer and keepers right?

The early style keepers are thicker and have a square piece that fits the valve.

The late model vales are thinner and have a round piece that fits the valve.

With both setups, the keepers end up about flush with the retainer.

 

Regardless of new or used, the spring install height should be checked when swapping parts around.

 

I'm sure there are some things that were done that no one knows about.

It's like they run out of a certain part and find something else to put in until the new inventory arrives.   There's all kinds of stories  like that.

It's good to know that you don't have to worry about getting some special valve spring shim when you need them.

 

Rich

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the real problem  come up when you have a reman head from some one like  clear water or any of the other places,, they most certainly  will not have  quest  valves in them  nor  quest springs, also the two engine have diff  spring install height , for another thing the caravan  spring  has only 60 lbs at  install height  vers 74 for  for new quest springs , useing  valve spring shims   is  some thing that has been in  use for many years  and will cause no problems at all if  proper clearances are maintain'd

of course you need to measure the springs  you have to  get an idea of the lb pressure they have  already at the install'd height and the  lbs   with the add'd shims , no one said to blindly  start installing  shims , and  the use of  other then a stock cam would greatly effect the ability  to  do this due to the higher  lift

 

now if you  get a bare head and swap your valves and springs  sure you  know  what  you have

 

the clear water head i did today  only had  1.570 install'd height to start with , so   while i  am only useing a stock cam(and most likely never will go to a bigger one) i only  went to .060 shims , of course if i  ever go to a 284 cam i will have to  replace the springs with  new ones to prevent  spring binding

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this  a good  reason for at least  checking the  install'd heigth,, with a  1.6  you will have no trouble  with a  heavy duty set of springs,  but  with a 1.570  you could  come up with  too much  pressure and  cam  wear , remember the schnider springs are 100lb  at 1.6  , i have even heard of  guys that could  not get more then 1.5  install'd  heigth,, now thats realy  pushing the  limet on  spring pressure
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