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Im testing the waters about upgrading my 86 from the stock 305cu to something larger like the 350cu or 386cu and I'm curious if the engine mounts will be the same? What are my options for a tranny and diff, as how big i should go with them to handle the extra power sent down the line. Or instead of doing an engine swap what  could i do to the 305 that would get me up there in HP but at the same time not hurt the wallet so much like a bigger camshaft, better intake/exhaust and definitely a better carb. Comment what you got in some of your rigs, what works well, what you wish you would have done exc.... Thx

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You should be able to drop a 350 in it without problem and as far as motor mounts go, everything should bolt right up.  Places like Summit and Jegs sell complete 350's ready to run quite reasonably priced, or as long blocks and all you generally need to supply are things like the intake, valve covers, distributor, carb and so on.  If it were me, I'd look for a 1996-2000 long block with the vortec heads (no, 305's of any year do not have vortec heads), but you would need to verify that the long block you buy has provisions for a mechanical fuel pump.  Why a 350 with vortec heads?  Arguably the vortec heads are the best out of the box iron heads GM ever produced, including those from the hot rod days of the 1960's and up to 1970.  Their only limitation without machine work is camshaft lift which is limited to about .450 lift, some say you can go a bit more, but for a truck you're looking for torque, not high RPM, so a high lift cam is not needed anyways and there are several aftermarket cams that will stay under the lift limitation and give you tons of low end torque and you'd make 300 HP pretty easy.  The other plus is if you go with the 1996-2000 engine you get the roller cam block, so no worries about breaking in a flat tappet cam shaft.  Summit and Jegs have cams they can recommend and would work nice.  I'd go with a dual plane intake designed for idle to 5500 RPM operation (the intake will have to be for vortec heads), a 600 CFM carb such as an Edelbrock performer and you could throw a set of headers on it (also from Summit or Jegs), a free flowing dual exhaust and you'd have a nice combo that would be fun to drive.  You'll be fine with the transmission you have and you really wouldn't want to throw much more power at it than the recipe I outline here.  One thing not mentioned in your question:  Is your truck computer controlled or is that part long gone?    

Edited by ifixedit
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