back cut exh as well as in. valves?

chad

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Machinist is finally gettin to the 250. Just in time I got the '79 Fairmont head from A1A in Lakeland.
He'll back cut the valves but when he asked about the exhaust I said I didn't know. Cost more? He said "no, & I'll do so unless U telephone me and let me know not to."
Again, all mods are to make this inta a lill tq monster.
1) What should I tell him about the exhaust valves?

He ordered a Comp Cam: 260, 440 lift, 110 lobe separation.
Will deck the block,
probably boar .030 (will be a 254 ci engine),
Moly top ring,
Re-grind crank,
lill machining to place vinton seals for valves (not umbrella),
"average out the comb. chambers" w/a machine (no hand smoothing of the bowls),
& all name brand internals (oil pump, bearings, gaskets, pistons),
the head will be ready to place on block when done.

2) Should anything be done differently for the '79 head? Weld up any taps, fittings, etc?
Thank you -
 
OK, thanx, dude.
I C U at other forums/sites too - good egg, helpin out!

all mods are to make this inta a lill tq monster

"...a good build…"
I thought the LC should be a higher number (112)?

Anybody got other ideas to increase tq not HP?
(will advance cam)

Still tryin to get an RBS (gunna have hood clearence issues) the 1v & 215 cfm seem right for the low rev tq…
I think (don't know) the carb will B alright on the gradiants (off camber when on hills creates fuel starvation to carb).
 
be a bit careful with lobe separation angle. if you are building a low compression engine, you can trick the engine into thinking it has a higher compression ratio than it really does by widening the lobe angles. however onve you start raising the compression ratio, you want to narrow the lobe centers up to avoid going too high with the dynamic compression ratio. i think for your build the 110 cam is just fine.
 
shootin for 9:1, 9.1:1, I think he said it might go as high as 9.2:1.
also: 1) "chambers will not be w/in 5 cc of each other" - he'll machine the head (rather than a hand burr)
for 2) comb. chamber smoothing, just "averaging" the CCs (I guess that means not bringing them all to the sz of the biggest?).

The Carter RBS - will that get into a fuel loss situation if tipped off camber? I'll continue @ about 70% off rd, 30% on rd use.

Thanks again!

Back when it's assembly time (or less)…
:cool:
 
i just realized, you said you were looking for a carer rbs? if so then PM me, i have at least one, and i think two.
 
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