89k5350
1/2 ton status
ill have to find out soon the motor is at my dads house
CK5
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350 engine build
- Thread starter 89k5350
- Start date
Being a four bolt main block will do you absolutely zero good.
It will also not do you any harm.
Martin
It will also not do you any harm.
Martin
89k5350
1/2 ton status
also when I pulled intake and heads off I found that whoever worked on this motor had blocked off a couple coolant passages on the heads I believe. any reasoning for that??
That is pretty standard.
Martin
Martin
89k5350
1/2 ton status
with out knowing cast numbers why would you think this motor has the corner bolt valve cover heads with the tbi unit?
Because someone cobbled an engine together for it.
Martin
Martin
89k5350
1/2 ton status
well that part was kind of obvious... I mean is it likely to be an older block and heads with aftermarket intake manifold for tbi or is it a tbi motor with different heads and intake. id like to find this out so I can get an era.
Then check the casting date. We can't tell you anything from behind a computer screen unless we see a picture......
Martin
Martin
Tbi intakes will fit older heads and a 4 barrel intake will fit tbi heads. The center 4 bolts are at slightly different angles. A little grinding can open the holes up to make it work.
It's the vortecs that are a totally different breed.
It's the vortecs that are a totally different breed.
89k5350
1/2 ton status
ok that makes sense then.
1986 had a carburetor, and angled center intake bolts, not?
Martin
Martin
89k5350
1/2 ton status
well I looked up the cast number and they are 305 h.o heads 58cc lots of compression but no flow. could I put bigger valves in these heads and port the runners? or would I be waistin my time
How did it run before?
Depending on how that engine was originally put together, that could be pretty high compression with a tendency to detonate, not a good idea in general, but even with a tiny bit of pinging, power is reduced (through knock sensor timing retard). No idea what the 305 heads flow, probably no better or worse than 350 heads that era.
TBI heads are good for lower RPM motors, Vortecs are obviously good, but a flat top piston, .040" quench, and ~9:1 compression will have you running 87 octane and no knock, assuming fueling and timing are handled correctly.
Depending on how that engine was originally put together, that could be pretty high compression with a tendency to detonate, not a good idea in general, but even with a tiny bit of pinging, power is reduced (through knock sensor timing retard). No idea what the 305 heads flow, probably no better or worse than 350 heads that era.
TBI heads are good for lower RPM motors, Vortecs are obviously good, but a flat top piston, .040" quench, and ~9:1 compression will have you running 87 octane and no knock, assuming fueling and timing are handled correctly.
89k5350
1/2 ton status
it actually ran really good it never detonated when it was all together in my blazer It had adjustable fuel pressure regulator accel coil headers true duals she ran pretty dam good
If it ran good and did what you need it to do, put it back together the way it came apart, obviously after having everything refreshed. Really no reason to mess with success IMO.
89k5350
1/2 ton status
I definitely cant disagree with you on that. the motor ran great but it always did have a tick which gives me an excuse for bigger roller cam hopefully.
89k5350
1/2 ton status
ok so im actually reconsidering just having the 601 heads (305 ho) ported polished and the 2.02 1.60 valves put in. any inputs on this idea? or would you take the time and money for the vortec heads and intake.
Vortecs.
Martin
Martin
