1) Anyone here running a XE274H with trick flow 23* heads?... If so, what was your pushrod length? Trick flow recommends 7.850 with their heads, and comp cams recommends 7.794 or 7.800 with their cam.
2) So I don't have the car down for a long period of time, would it be possible to bolt the heads to a pre-87 350 block, install the cam (bearings are still in there) install the lifters and rockers arms then measure? I'd hoped to have all the parts for heads/cam install at the same time meaning less downtime.

I wouldn't even ask this except that trickflow stated the recommended pushrod length for their head was different than stock.

Any advice here would be appreciated. I did read the tech article on trick flow's website about measuring pushrod length and I'd like to get this right.

thanks!

 

7.794" is the stock length.

Every engine is different. Buy yorself an adjustable push rod and pick the optimum length.

My guess (having had that cam) is that you'll end up with push rods at least 7.850", and maybe 7.900". Seems like mine were 7.900" for optimum geometry. But that was with a different set of heads from yours.

 

Thanks for the info...
How much do the adj pushrods cost and where can I find one? I checked the local Autozone - no luck.

What do you think about my idea of mocking it up on the other engine block?

 

You can order one from Jeg's or Summit or get it at your local speed or racing machine shop. Most of the major cam mfrs offer them: mine came from Comp. It's about $30 IIRC. It's one of those pieces of test equipment that every serious engine builder should have, along with micrometers, dial indicators, calipers, feeler gauges, etc.

You could mock it up on another block, if you know that its deck height is the same, and you use the same cam and the same set of heads that go into the finished product. That introduces an awful lot of uncertainty though. The smart thing to do though is to not order push rods until after you have the whole rest of it put together, everything in the valve trains installed including the heads torqued to specs, the cam & lifters and the rockers, then check it with the adjustable and order accordingly.

 

I hear what you are saying, but:

a) I may build an engine in the future, and I don't think that 1 or 2 engine builds justifies a whole set of measuring tools (expensive). That's just my opinion, of course. Maybe I can borrow one from a machine shop? That would partly solve my problem, but;

b) I am trying to avoid a couple days of downtime just waiting for pushrods once I know the length and order them. I wouldn't feel safe driving around with the stock length pushrods in there until the correct ones came in...so, I dunno. I didn't think about the deck height of the block - that could be different for all I know. I should have known this would be more complicated that I thought.