Help me understand 5.0 disparities

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Bextreme04

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Also, if we're talking apples to apples in either 80s or 90s spec, neither of them had great heads (speak in Mustang vs Camaro, not truck) but the 305 FLAT. RAN. OUT. OF. BREATH. at 4500. Carb'd, TPI, TBI, they all were done at 4500, nothing but noise (or windowing the block :anitoof:) after that. The Mustang would rev to 6-6200 and made power well past 5.
The biggest problem is the small bore of the 305. It greatly limits the valve size you can run and therefore artificially limits the amount of flow you can get from the heads. You end up with the worst of both worlds for making power. It does OK for torque at low RPM, but even that is not great compared to an engine that can get decent heads and valves on it(350, 400, etc..). That's why the 327 is such a great racing motor. Same bore as the 350, but a much shorter stroke. This lets it wind up fast while being able to have all the same airflow potential as a 350 or 400. Airflow is power.
 

Number 6

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I asked this question before, but this tread seems to be a good fit for my project square body 1987.
I'm calling a classic restoration place here in Mexico City who probably has a rebuilt 305 with a 2 barrel steel intake manifold for sale with a Motorcraft carb adaptation. Jeep guys like that carb since the float works better on angles and steep inclines and decent.

HOWEVER, I've bought a new Weber 38/38 Outlaw to swap into my '87 "utility" Suburban which currently has a totally shot 350 with a Q-Jet. My intension is to make an adaptor plate in order to use the 2 port intake manifold with the Weber 2 barrel.
Do any of you know the diameter of the GMC 2 port intake manifolds that came with the 305?
In the US '87 started using TBI. Here in Mexico TBI was sold from '90 through '97.
I do not need to be concerned with any smog requirements, the transmission is a 4 speed manual and I don't plan to run it over 4k RPM.
Why a Weber? Once you get the jetting dialed in, it really doesn't need to be messed with. I should also point out that I've had great success with 2 barrel down draft Webers in the past and also say this truck will primarily driven between 5000 and 6000 feet of elevation.
Any opinions and suggestions are appreciated since this is kind of an odd ball plan.

Thanks.
 

Turbo4whl

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The replacement for displacement is RPM(actually it's boost... but you get the idea:)).
This ^^^^

I liked my little 305 a lot! Ran very well for 80,000 miles until I burn a hole through one piston.

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squaredeal91

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I wonder why it had a hole??^^^^lol I bet she screamed till then!!
 

Turbo4whl

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I wonder why it had a hole??^^^^lol I bet she screamed till then!!
Yes it did!

Well here is why, the cylinder right under the turbo ran rich, #2 and the opposite cylinder #7 was lean. The rest all looked good. When I would get a misfire #2 plug would be fouled and not firing while #7 still firing, would have some of the plug negative burnt away.

So it was only a matter of time, yes burnt a hole in #7 piston. That is when I shoehorned in a BB and never looked back.
 

Matt69olds

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This ^^^^

I liked my little 305 a lot! Ran very well for 80,000 miles until I burn a hole through one piston.

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That’s how you fix the lousy valve shrouding from the small bore. You carry your own atmosphere!!
 

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