ach1992880

Saw this for sale on CL... with a very low price.

had this custom built by harold jenks,403 standard block, bored .040 over, trw 8.5 to 1 pistons, chrome molley rings, new harmonic balancer, new crank, new fly wheel, all rotating assymbly has been balanced, lunati voodo cam, .520 / .555 hydrolic, anti pumpup racing lifters,cyl have been o ringed 455 heads all new parts wth 1.6 roller rockers, ported & polished,hei distrib, alumin highrise, wth headers,starter,water pump, needs carb $4200.00 invested, 1500 miles

I'm a bit puzzled by this build personally... .040 over on a 403 is more than I've heard suggested, 8.5:1 pistons plus big block heads? I'd think this would end up as a very low compression setup and then to have what sounds like quite a bit of cam could make this thing a complete dog. It seems like a lot of money was thrown at parts that don't add up to a cohesive whole. I've sent the seller an email asking more about the combo, but am open to any of your (more well informed) input.

s i 442

I wouldn't buy the crank busting the block apart engine in the first place!

olds 307 and 403

Those big block heads will have slightly smaller chambers than the factory 83+cc 403 heads. If it is 0 decked and any milling was done to the heads, it may have more than 8.5 to 1. If the heads only have a clean up mill and the pistons were left way in the hole, it may be very low. KB pistons which come in .040" and balancing might be all that motor needs to make use of those heads. The 403 can take decent abuse, if built right.

ach1992880

I know there are strong opinions on these blocks one way or the other, I'm looking for something that would spend 0 time above 5k RPM, basically if the foundation of this thing comes out sounding good it will receive a fairly mild cam for a street driven car. I'm in search of more torque and midrange than i'm getting from my stock '71 350. In his reply, he admits that it's over cammed right now, runs at 185 with a 4 core radiator in his car currently, and is available to hear it run. I'm likely to take the time to go check it out anyway, we'll see what it turns out to be.

oldcutlass

How much does he want for it? The 403 is not a bad engine and can take some abuse.

ach1992880

800

oldcutlass

If it's a good running engine I'd be all over it.

cutlassefi

I sincerely doubt it has a new crank.
Never seen anyone O-ring a 403 block, not enough room between the cylinders.
Lift numbers are wrong on the cam and if it's either a 60804 or 60805 then neither one is good for a 8.5:1 403.

This guy might be talking out of his butt but I guess if the price is right it's worth a shot.

Octania

Price sounds good but upon passing inspection.
Pay the 800
Remove the heads and oil pan before leaving the premises
If bores and pistons and bearings all look right, then go home and change the cam and/or pistons to a reasonable combination.

If things are seriously imperfect, execute the money back plan.