Hello everyone. Names Ed i'm a long time reader. 1st time poster. I have a question that i can' t figure out and i could use some advice, guidance. I have a 1987 Monty 2.6L w/5spd. I want to evently go the turbo route but money is funny right now so that will have to wait (I'm going with stock carb mean while). I'm currently rebuilding the top end of my monty with new clearwater head and exhaust header for now. But my quetions are these. Can i use mechanical lifters on a hydraulic head and vice versa. I know carb has nothing to do with it ,But i want to install a performance cam meanwhile. I will be building the turbo long block. and the only cam that i could find was from T.E.P. and they call out for Mech lifters which is fine but when i go turbo i want to use the same head but with hydraulic lifters? Is this possible or is this some kind of pipe dream? thanks for your input
-Ed

I believe you can go with mech lifters but you need to change out the whole rocker assembly.

You can get a custom ground cam from TEP for I believe $169. Just have it ground for hyd lifters. I put a Clearwater on mine with the mech lifters and can honestly say, I prefer the hyd ones...

Stock hydralic cam with a turbo makes great power. I would not be looking for more duration.

Kevin

dont you want to lower compression?When I was into into subies when we went turbo we built the engine with lower compression to handle the boost.Or is everyone just running such low PSI that it will run fine on a stock set up?

you can use man adjusters on a hydrolic head but you can not use hyd on a man head.hte valves are diferant lengths.the man adjusters can make up for the diferance but the hyd lifters can not.when i got my clearwater head i got man adjusters and i am happy with them.but i dont mind adjusting them every 10000 miles.plus they are not as noisy as the hydrolic stock ones so i am happy.

Good point on the CR.

Ball park figures on boost VS CR on a 2.6.

Stock 8.7 to 1 should be able to handle about 5 to 7 psi of boost.

At 8.2 to 1 9 to 12 psi.

7.8 12 to 15 psi.

Stock on a turbo 2.6 was 7 to 1. That will get you past 15 psi provided the rest of the motor can handle it.

Higher boost levels need stronger parts and the oil jets to cool the pistons.

Kevin

just a random turbo thought but here goes.dont laugh.how much boost can the 2.6 handle without the oil squrters?i get why they are there on a lets say dodge 2.2 they can handle increadible boost without the sqerters.i can take the 2.2 in my shop rebiuld it and it can handle well over 20 psi.plese inlighten me.

I dont have any exact data. What I have is the factory added them and was running boost levels above 9 psi or so. They added them for durability, so to be safe it seems like a reasonable recomendation. For that matter they added a nitrided crank, stellite exhaust valves and a special alloy head and special pistons that dont have a thermal isolation slot through the oil ring.

None of us are going to duplicate the factory testing so I dont think we would ever know for sure. I do know the 2.6 is a very long stroke motor, so perhaps thats part of it.

I'm sure a 2.6 motor could be built with a nice set of forged pistons to live at high boost and no squirters. However I dont have any examples of that to make a recomendation from. In the mean time its very easy to add the oil squirters when the engine is apart for a rebuild so it seems like a safe bet to just add them.

If you want to experiment, sure let me know. <img src="/forums/images/graemlins/wink.gif" alt="" /> It would be usefull information, but would at the very least involve the cost of a motor to test and the time it takes to get 60,000 miles on it to prove its durable.

Till then I like to reccomend what has been tested / what I know works. IMHO its a bit better to error on the safe side.

Kevin

I don't know for sure, but I'd bet the squirters reduce temps on the pistons to help prevent detonation.

Dave

About the only way pistons have to lose heat is through the ring contact wil the cylinder. The oil squirters give some of the heat another path to coolant. Aluminum loses strength rapidly with heat rise. I would not do business with TEP based on reputation and my experience with them.

BTW, anybody ever do a combustion chamber volume on the 2.6????