Engine Quest pushrod question

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75DartSE

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Hey all,

I'm putting the Engine Quest heads on my 318. I have them torqued down and was about to begin installing the valvetrain. I purchased Comp Cams kit that engine quest recommended 1425-KIT.

http://www.compperformancegroupstor..._Code=CC&Product_Code=1425-KIT&Category_Code=

All seemed ok until we were putting the pushrods in, and they are almost 3/4" too short! It seems like this kit may be meant for a roller cam? I tried to do a search here and it seems like someone was using pushrods that were 7.650" long. I used on of my stock 318 LA pushrods that measure 7.50" long for fitment and it seems to be about the right length, although the slightly longer ones will get the comp magnum rockers away from the valve retainer a bit more.

I am aware that the pushrods need to be hollow for oiling and I do have the proper comp lifters to oil through also.

Does anybody have any experience with these heads or any magnum head swaps and the required pushrod length????

Thanks for the read, Kris
 
This seems like a similar experience I had with 302 when I converted the bolt down rockers to adjustables...they were too short by probably the same amount because the studs put the pivot point of the rockers higher. Any time you make that kind of change to the valvetrain, your best bet is always to use an adjustable pushrod and do a mock up and measure.

Probably not the advice you wanted to hear, but it's the best way to do it anyway.
 
75DartSE said:
Hey all,

I'm putting the Engine Quest heads on my 318. I have them torqued down and was about to begin installing the valvetrain. I purchased Comp Cams kit that engine quest recommended 1425-KIT.

http://www.compperformancegroupstor..._Code=CC&Product_Code=1425-KIT&Category_Code=

All seemed ok until we were putting the pushrods in, and they are almost 3/4" too short! It seems like this kit may be meant for a roller cam? I tried to do a search here and it seems like someone was using pushrods that were 7.650" long. I used on of my stock 318 LA pushrods that measure 7.50" long for fitment and it seems to be about the right length, although the slightly longer ones will get the comp magnum rockers away from the valve retainer a bit more.

I am aware that the pushrods need to be hollow for oiling and I do have the proper comp lifters to oil through also.

Does anybody have any experience with these heads or any magnum head swaps and the required pushrod length????

Thanks for the read, Kris
Click to expand...

EQ probably made the assumption that since you bought a magnum style head...they were going on a magnum engine which have taller hydraulic roller lifter...MP used to sell conversion pushrod kit for the magnum to LA conversion...they were 7.625 in length...and alot of people stated they were a little short...so you are probably correct with your 7,650 pushrod.....

I have a set of eddy magnum heads that i had set up on a LA 360....with solid lifter cam which takes a longer pushrod then hydraulic ...and I ended up buying 7.750 long pushrods...
 
Thanks guys. I'm going to go with the 7.650 ones. I talked to engine quest and they weren't aware of any issues but had never tried to install that crossover kit from comp cams on an LA even though that's the way they recommend it on their website. I told them they might want to re think that. Lol. They had me talk to a guy that's done lots of these in Ontario. He said these heads are better than the RHS and he's used both in the engine masters challenge. He said that I'm on the right track also with those long pushrods too.

So I'll get the pushrods tomorrow and be back on track!! Thanks for the replies with your experiences.
 
I have EQ heads on my 408 and had to use 7.55" pushrods for optimum valve train geometry, but I'm running a solid cam and Harland Sharp rockers and the block was decked. Different options like that can all affect what you need. Instead of going with what everyone else runs you really need to measure what your engine combo requires. It's really simple to measure with an adjustable pushrod. If you don't have the right length rods the geometry can be off and cause a loss of performance and possibly even mechanical issues.
 
Thanks for all the advice. I've done all that pushrod checking before. I have the shortest checker tool but it's not quite long enough so that's why I used my stock pushrod as a checker. It's also hard to do when the lifter isn't pumped up too. Lol. It just bugs me when it's recommended to use certain parts and they are incorrect.

After speaking with that Jesse fellow in Ontario who has built many very similar motors and what 71beater and others have mentioned, I'm confident in my decision.
 
75DartSE said:
Hey all,

I'm putting the Engine Quest heads on my 318. I have them torqued down and was about to begin installing the valvetrain. I purchased Comp Cams kit that engine quest recommended 1425-KIT.

http://www.compperformancegroupstor..._Code=CC&Product_Code=1425-KIT&Category_Code=

All seemed ok until we were putting the pushrods in, and they are almost 3/4" too short! It seems like this kit may be meant for a roller cam? I tried to do a search here and it seems like someone was using pushrods that were 7.650" long. I used on of my stock 318 LA pushrods that measure 7.50" long for fitment and it seems to be about the right length, although the slightly longer ones will get the comp magnum rockers away from the valve retainer a bit more.

I am aware that the pushrods need to be hollow for oiling and I do have the proper comp lifters to oil through also.

Does anybody have any experience with these heads or any magnum head swaps and the required pushrod length????

Thanks for the read, Kris
Click to expand...
Dart-75se just be careful with that comp cams rocker gear for those heads, i found out when i purchased the same kit that the rockers are poor quality and i found on mine that some rockers bottomed out on the studs causing some to bind up.I ended up replacing all the rocker gear and guide plates with Cranes 1.6 Gold rollers with all Crane Guide plates with rocker studs which are of much better Quality.Im using a solid stick in mine!Those Heads will make that teen run well with the right cam. Where did you purchase your heads from as i had some trouble with a set i purchased from a vendor and they didnt allow enough valve stem to guide clearance and i had major engine failure.I was too naive and trusted his work.Buy em bare and have em fitted out from a good machinist!
 
67GT, thanks for the heads up! I always check and double check things before I run them up. I will double check after break in and a few passes. Those rockers don't look all that high quality but at least they are just generic chevy ones so they are easy to come by.

I'm using a comp xe268h cam because my engine guy built a nice 360 with that cam and it worked well. It will also work with my stock convertor. I bought the heads directly from engine quest fully loaded. I ended up putting some new LS1 style beehive springs and retainers on to handle the lift of the cam without binding. I have plenty of clearance between the retainer and valve seal so it won't bottom out there. We had afr heads that didn't have enough guide clearance and it was all bad!! Been there done that! Lol
 
Mopar made some conversion pushrods...but like tony said they were a little too short..and some were bent from the factory....
 
bad440 said:
Mopar made some conversion pushrods...but like tony said they were a little too short..and some were bent from the factory....
Click to expand...

Those are a bit short for regular hyd. lifters but they are close to ideal if you want to run anti-pump-up lifters which call for almost no preload.
 
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