worn valve stem

GottaSki wrote: I could freshen one off season while running this 351 lower for a spell longer So would just need a mid-sump pan and pickup, distributor, and 52oz imbalance flywheel, and a used, popular intake. And fresh head bolts. pushrods

My 302 was/is all automotive junk yard found stuff so there is workable pickup/sumps out there - if it comes to go time Ill look for the notes/parts.

I assume there is a parts store flywheel available that would work as well from a manual transmission 5.0 era mustang or something. But maybe not if diameter or tooth count changed from the 1964.5 mustang flywheel design that early 302 and all 351w marine motors used.   I know there were added holes on later ones for bigger clutches but I don't know if the diameter or tooth count had to change as well.

Either way one is available aftermarket but would be cheaper if its an autoparts store pick up. I ended up having my 28oz flywheel drilled on at the local engine balancer to make it match a later 50oz crank - but I did that cause I was in a hurry- it would deprive you of a perfectly good 351w flywheel.

Pushrods with the TW heads will absolutely not match anything stock in either of the deck heights so a few bucks there for sure.

Good stuff

Thats great sorting out the pan number, thank you.   I knew about what shape would work, but from pictures it was difficult to confirm what is the front and what is the back. Appears Eighties Econoline applications

Duane I studied the Flo-Teks for good long while, please tell my how they have been, or point me to text if you've already written it up.


It appears the TF heads switch from 10 degree locks and retainers to 7 degree when building a head for a roller cam, along with heavier springs.

Day early, dollar short...ugh

Great deal for someone doing similar...
https://westernmass.craigslist.org/pts/d/springfield-trick-flow-tw-170-heads/6828973152.html

Checking PVT , and dialing in camshaft

With your skills you should have that thing marinized in no time

So I might be missing something but it looks as is you are measuring valve movement but - .050 spec should be tappet movement, so perhaps its a rocker ratio induced error?

Youknow Joe that could very well be it!
Recently watched too much pushrod measuring /rocker geometry tutorials, and likely mixed up the techniques
much obliged!

Last night verified that 0 degrees offset results in all cam events being within 1 degree of the card. when i do it right....

Lift at cam measures right on as well.

I think the scorpion rockers sneak a little more than 1.6 ratio, which is fine, there is plenty of PVT.

Now I'm reconsidering not using the Rhodes lifers that came with the cam.

My calculus...

214/224 is not too crazy duration it seems , and i don't want a non-linearity to occur in the power right in the middle of slalom speed ranges.    Appears these come alive 3000-3500, and thats the wrong place for a big ramp in dHP/dRPM, as ramps go both ways, and the major input should be throttle opening, not rpm

Additionally I don;t want to hear them clicking after all this effort

Updates...

re re re confirmed PVT both methods, clay and dial indicator with setup valvespring.

got .095" intake and exhaust was so over .200 i didn;t commit to a solid number, was plenty and didn't even dimple the clay



Heads are now bolted down and torqued

Measured and got push rods sized to where rocker fulcrums are 90 degrees to the stud at 50% lift. Measured that with a solid lifter

Installed them, and new std hyd lifters, both with assembly lube and set lifter preloads and locked them all down,


I'll need to modify the baffles in the valve covers, as they hit the lock down bolts, rather not buy new ones.

I then clocked the lifters on apiece of paper, and gave the engine 20 revolutions, then checked th position of the lifters to make certain they all rotated some





I've been playing further with the aesthetics of the engine as it goes along.    Prior pictures with the rustoleum hammered black on the block and covers was looking quite acceptable. Noticed that the camera errently picked up browns in the light that got me thinking to wth maybe better embrace the browns, and did some testing
that said, keep in mind the boat is the typical all- chocolate brown hull with tan deck supreme most are familiar with ..

Last week, with the heads still off, retaped the block, (easy, used the old front cover as a mask on the front of the engine) and hit the block and covers with the hammered brown,
There would be a whole lot of silvers going on, so wanted to better highlight the heads and exhaust, so hit the Intake and front cover with hammered copper.
It pained me somewhat to paint a new intake, but they don't look great for long left bare anyway.

I fully understand, its not for everyone. And may only work with a brown-themed boat. But as far as painted engines go, , i'm satisfied with the results

I placed the covers and intake on and a couple bolts on the exhaust to mock-up...

thanks Joe! i'll heed that, and look out for that style of cover interference too. Glad you said so
I won't have near full travel on the rockers till i hit it with the preluber

Carb will be my correct list Holley 600, about 12-14 years old, and trouble-free
I suspect it could leave something on the table for cfm, but alls well for now.
I'm aiming the 34-36mph throttle compensation should improve , as at 36 was getting a little flat to inputs and likely close to transitioning to partial secondaries under load, which don't respond quick enough to throttle inputs like that.

I concur, could do well on everything but flat out big numbers.
The hull is low-lift much like a stars and stripe MC, so this wont be an impressive speed monkey, and that 4-blade oj is going to have rapidly increasing parasitics above 4500 rpm.
these three things together I suspect will keep top mph away. Like you said, not bad because the usage and hull, don't want to spend too much time fast anyway in that hull.
I have a 3-blade later issue federal for playing with too, the boat skis well with that too.

The carb is of the later vintage to have its own PVC port. The old spacer will produce vacuum leaks on the newer edelbrock manifolds as many encountered, Vic want people to use their carburetors i suspect
I bought a black plastic spacer hoping it was entire solid, but it has voids on the underside also. Haven't figured that out completely yet.

It is looking great.
Carter Carburetors had a Carb Selection chart printed for years. It states a 348-360 Cubic Inch engine will need 610 CFM at 6,000 RPM.
Same engine needs 560 CFM at 5500 RPM.
Your 600 should give you great performance unless you wish to twist it over 6,000.

The 351W with large main journals heats up your oil quickly when run over 5,000 for any extended period.   Large mains support the torque very well and help when running loaded all the time like a boat engine is always exposed to.   For High RPM running with these engines racers would install smaller diameter main journals to keep oil temps in check.
These same large mains have made the 351W a favorite for boat manufacturers because they last a long time while working hard.

Question - What do you recommend about blocking or leaving the heat crossover?
I'l leaning block, given the typical temps of operation. but i need to decide shortly.

Its too late for me to tap and plug the crossover port on the heads, i'll get chips down near the valve seat.
but its a 1/4 to 5/16 hole or so on each head. unlike the stock heads wide and irregular shape

My intake gaskets are fel pro 1250 , they match the head's port size well, but not blocked on the heat crossover.

Appears i have some work to do on the intake.. I can trim the tab on the intake gasket so it lines up decent to the 1.4x2.0" ports on the heads, but i'll need to remove about 0.20 in width and 0.30 on height on the intake ports for better matching. The performer runners are comparatively narrow to the head' port's. Moreso on the outer runners are necked down quite narrow.

Your intake gasket set did not come with the crossover blank off's or reducers?

GottaSki wrote: My intake gaskets are fel pro 1250

The set I bought a couple of years ago had them,maybe they were overlooked?

GottaSki wrote: Egad, yes, they are in the package. Just hogged out the intake. Think i just lowered the engine weight by another pound If trick flow had a low ride dual plane intake available, that would have saved a lot of work!

If you didn't do this





Then you still got off easy...