aftermarket cams?

So I have the 82 xj 650 and I'm wondering if I could get away with putting the 750 cans in it and what I would have to do to make it work, has anyone done this? And what was Ur results?

 

I think they drop in, give more lift, they may affect your jetting needs, and you should plan on re-shimming.

 

Would u define reshimming for me, I don't have a clue what that means lol

 

The all-important valve shim clearance - - we have a shim-on-bucket valvetrain adjusted within specs of just a few thousanth inch.

 

Haha so excuse my ignorance but will u explain the process and theory behind it all?

 

Buy a manual!!! And do a search on the subject!

 

First of all I HAVE a manual, second what do u think a forum is for? Are questions restricted only to Google or can I look for the answer on here also? Thanx

 

ok i will explain for the people that don't want to help and do what is right. The importance is that if you don't shim properly the space will become to loss or tight depending on the wear of the engine. and if it gets to tight you valves will not close all the way or to much distance and your cam will slap your valve.

In other word it is very important and needed to get proper performance out of your XJ.

but the 750 will fit right in i am about to do the same thing it will increase you lift. and you duration to. Good luck i will be doing it come the winter time.

 

Awesome, thanx to both u guys that helped me with my questions, that cleared up that mess, but one more final one, if I'm using a used set of cams is there a break in sequence I have to go threw? Lemme know cause any and all info is much needed and appreciated

 

There is no break in time that I know of. The only thing you have to do is just check clearance. And u should me good. And enjoy

 

Awesome thanks for the help

 

Since you will be using some shims with a wear pattern on a different cam, maybe you should change your oil and limit high RPM's for several hundred miles (just to be safe).

Add a few magnets to your oil filter - - you'd be surprised what they catch.

 

Well my buddy that owns the local shop said he has a shim set so ill be putting new ones in and ill definatley be putting in new oil cause I'm gonna do new chain guides, rings and full gasket set with a new clutch and also currently my motor has 38,000 miles so I've already put magnets in the bottom but thanks for the tip and input you guys been great

 

P.s. If anyone has anymore input on any other power upgrades or things I should watch out for then lemme know thanx

 

With the work that's ahead of you, and the help of a mechanic, you could get the "750" block and pistons and build a "hybrid" 700. This would require a re-jet. Add a light shave for higher compression and you might find 10 extra Horsepower with the 750 cams.

However - this puts you into the "no-man's land" of Frankenstein tuning, and no-one can give you proven, sound advise with this set-up.

 

Hmmmmm........ that might be a project for a later date then. I'll just do the cams for now. Thanx

 

Any ideas on how much more power you could see with just the cam swap?

 

Wouldn't it be easier to just replace the 650 motor with a 750 motor?

 

Well for the cost of a motor and not knowing how it was recently driven and if its in good order internally I think it would be better to just keep my 650. Plus it saves the time on pulling the motor. Besides I'm just wanting to put the cams in for fun cause I like tinkering with stuff lol

 

I understand the tinkering.LOL If you can find a good running 750on ebay or from a XJ member, the cost would probably be the same as what you want to do to the 650 without the work. I was on ebay yesterday and saw a 83 750 and a 85 700x for cheap.

 

Awesome, but I already bought my cams for 20 last week lol

 

Well have fun and post pics. :lol:

 

Will do

 

ur doing the same as me. but i am getting a whole new 650 head and having the valve increased in size and also porting the intake and exhuast.