76 maverick 250 new cam

sorry? I thought this wuz a cam selection thread?
 
no hard'n fast - I'm just a lill confused (some 1 who doesn't multitask either, well, sorry - its me not U).
I'll step back into the shadows now, left U w/alot of....stuff....in #4,7,16,19 w/o return. :rolflmao:
 
Maholmes76":2aqfpdcc said:
Was lapping the valves today and noticed small Annular groves as I did them. I am using the lapping hand tool. And permatex valve grinding compound. Is this going to be ok. Not sure this is the first time I have lapped valves
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After you lap the valves in. Take the intakes to a machine shop & have them do a 30 degree back-cut close the the outer lapin line.
Its worth about 10 HP due to better intake flow.
Don't forget the distributor, it will wake up your engine. Bill
 
Chad

Sorry for the lack of response. Not real good at this forum stuff. I have been taking your advise. And getting my ducks in a row. Can’t find a way to respond to just you if you even can. Still learning.

Wsa111

Thanks for the advise. So to be clear you are telling me to have the intake valves cut back correct?

Now that I am getting my stuff together I will post all my info on the car cam ect and we can figure out the carb and Distributor
 
Maholmes76":2mpk7npa said:
Chad

Sorry for the lack of response. Not real good at this forum stuff. I have been taking your advise. And getting my ducks in a row. Can’t find a way to respond to just you if you even can. Still learning.

Wsa111

Thanks for the advise. So to be clear you are telling me to have the intake valves cut back correct?

Now that I am getting my stuff together I will post all my info on the car cam ect and we can figure out the carb and Distributor
Click to expand...
A 30 Degrees back-cut will gain you 10 HP.
Just give a shout when ready. Remember my HEI will increase in cost after Jan 1.
 
Howdy back All:

Happy New Year. I'm in the midst of my wife's B-day celebration so this will be short. When changing cam on a '73 and later 250 engine be sure to order a timing gear set for an early, before '72 250. Refer to page 46 in the Handbook. FoMoCo advance on the 250 cam timing set for better emissions numbers--- But less power on later 250s. For best cam performance use the 250 timing set from '69 - '71.

I ordered from NAPA. S414 for the cam gear, S415 for crank gear and 9-363 for the chain. I placed that order about 15 years ago so here's hoping that they are still good numbers. Good Luck.

Sorry to by-pass you Bill. I'm short on time and figured that this may be useful info to all 250 builders on the site.

Adios, David
 
Maholmes76":2khlzqxl said:
Ok it’s the 250. I ordered a comp cam for the 240-300 and thought I had messed up but come to find out the cam I ordered will fit all 10 inch deck height straight sixes.
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Yes he would be right that the deck height of a 240 / 300 six would be 10.00 inches centerline of the crankshaft to top of the block deck! Yet a 250 Six deck height is at 9.469 inches which is only .531 less then the 10.00 inches deck height of the big six blocks which is also close. Depending on how you were measureing this in the car it could be possible to be off by as much as a 1/2 inch. Glad you got it all figured out now, lots of good suggestions for your 250 build up good luck. (y) :nod:
 
Thank guys for the information! Y’all have been great! I will share this with you! Comp Cams has their wires crossed with their information. They show the 250 having a deck height of 7.88 inches and they have the wrong timing chain setup for the 250. I will order the timing set for a 70 Maverick that way the timing marks will not be advanced. Thanks again!
 
Maholmes76":3eqqgt19 said:
...that way the timing marks will not be advanced. Thanks again!
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the marks are to B ignored.
As per Bronk above - degree each'n every cam ever installed.
As per David above get the 'early' timing set (see his book we've been quotin for back cut to valves & he cited above 4 this).
Good Luck~
(y)
 
Great news. Chad, just shoot me a PM when you are ready.
David-CZLN6 thanks for confirming my findings on the difference between the early 250's gear & the later 250 camshaft gear.
It would be expensive, but an offset ground crankshaft from a 200 using a 1.88 Honda rod & custom piston might yield 220+ cubic inches.
You might give away a little torque, but treating the 220+ with proper bolt ons would give a 250" a run for its money.
The plus is a decent full roller timing chain plus many other gains.??
 
These 1.88" honda rods - what model / engine are they from? And what's the c-c distance?.
Tried a search here. - but 1.88" is too small for the search function
 
gb500":5rdz8g5m said:
These 1.88" honda rods - what model / engine are they from? And what's the c-c distance?.
Tried a search here. - but 1.88" is too small for the search function
Click to expand...

anyone know the model /engine type for thse rods ?
 
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