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Anyone have some reccomendations for a twin stern drive setup staying with iron heads. looking for cam intake and carb sugestions
 

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Pretty easy:
Holley 600/650 or Edelbrock 600
Performer RPM or RPM Air Gap (GM Bowtie if you want cast iron)
Comp XM262H hydraulic or XM270HR if hydraulic roller

Wallah.

Note: if you have twins, there is a slight chance your motors already have the highrise GM bowtie intake which is just as good as the Performer RPM intakes.

What years are your engines ? They may have blocks ready for HR cams making the switch over easy. If they are new enough, they may have Vortec heads and HR cams already.
 

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89 with bravos i think the intakes are iron though going to tear down next weekend have about 600 hrs on them wanted to warm them up a little what kind of H.P. with combo you think?
 

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Would it help to use a carb spacer with that manifold or modify by lowering that divider between the 2 plenum,s
 

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Usually the Bravo equipped small blocks came with the Bowtie High Rise Cast iron intake. Look for the Bowtie cast into just behind the carb, up on the carb pad. This intake kicks ass - no reason to change unless looking to save weight (aluminum) or they are rotted out.

Look for 310-320 or so hp with parts I've mentioned. You'd need better heads to up the power from there.

When you tear down the engine check to see if your block is set-up for accepting factory hydraulic roller cams. If it is, I'd go this route. Pretty cheap to go HR if yoou use the factory parts - lifters, spider and dog bones, cam retaining plate, etc.
 

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A pair of 383's would wake the engine compartment up.
 

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Thanks cfm looking to tear down in the next 2 weeks i will see if i can get more info then thanks for the replys
 

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Chris i hear you are the man of cams any input on a na 350?
Bang for the buck I would add CID to the boat. 2 383's even with OEM heads are better recipes for a boat as you let the CID make the power, not rpms and in doing so keep the rpms low which long term makes for less maintenance.

Pair a couple of rotating kits with a mild hyd roller and some bowl hog work and 202/1.6 valves in the OEM heads you would have a nice pair of 375HP engines and be knocking on 400#/ft of torque.
 

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Anyone have some reccomendations for a twin stern drive setup staying with iron heads. looking for cam intake and carb sugestions
A pair of 383's would wake the engine compartment up.
Chris i hear you are the man of cams any input on a na 350?
Bang for the buck I would add CID to the boat. 2 383's even with OEM heads are better recipes for a boat as you let the CID make the power, not rpms and in doing so keep the rpms low which long term makes for less maintenance.

Pair a couple of rotating kits with a mild hyd roller and some bowl hog work and 202/1.6 valves in the OEM heads you would have a nice pair of 375HP engines and be knocking on 400#/ft of torque.
What carbs, intakes, and cams would you use on his 350's ?
 

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and some bowl hog work and 202/1.6 valves in the OEM heads you would have a nice pair of 375HP engines and be knocking on 400#/ft of torque.
What would be the cost difference of refreshing his heads, adding larger valves, springs, etc, etc vs just buying say a set of Vortec's with a better spring/stud package installed ?
 

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What would be the cost difference of refreshing his heads, adding larger valves, springs, etc, etc vs just buying say a set of Vortec's with a better spring/stud package installed ?

Labor and parts around $450 to "freshen" heads.

Go to Vortec's you need manifolds also.

Stroker kits with a cast crank, coated cast pistons, are pretty resonable these days. Keep the rpm below 5200 and build some torque monsters.
 

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Does that include the larger valves and the bowl work ?
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I'd really like to know the thread posters budget in this 'performance' rebuild. 383's can be done cheaply, but it really depends on what you call cheap and it also really depends on what power you are looking for because your stock 350's can remain the same size if your components are in good shape plus you can really wake them up, without resorting to all new motors.

Remember, it's very easy for someone to say 'this is the best bang for the buck' when it's not their wallet.

The actual, real bang for the buck, is getting rid of the OEM cams and upgrading your heads to accept the performance replacements. Next, is getting better intakes if you don't already have the Bowtie intakes on your motors, which you may. The next bang for your buck is replacement performance cast iron cylinder heads.
Then followed by increasing cid.

If you need new rotating assemblies, then yes, this changes things and you should contemplate 383 assemblies for they are not much more, if anything, expensive than 350 assemblies now a days.
 

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does anyone have experience with the dart SHP sbc block.

I would like to have someone put a 3.85" crank in one with a 4.155 bore, but i dont know about the cam clearance with that crank. Rather small hydraulic roller, max lift at the cam about .367.

They are already clearanced for a 3.75 but a small base circle cam is required there (something like a .900 core cam is recommended, whatever that is).

at 10:1 or so i expect 515hp at 5700 rpm, and then a hundred shot on that to about 6100.

These calculations are based on the present 377cid engine...same bore/stroke ratio, and better heads.
 

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there are a couple of ways to "383" your 350, the Budget way- have the
mains turned down on a stock crank,(400 crank) use the stock 5.535 400
rods, and an off the shelf 350 piston. although, nowdays it's prob. cheaper to buy a cast steel stroker crank from scat than to spend $ on
machining the inferior stock piece! and as far as using the cylinder scrubbing 5.535 rod, I don't really like them either! so where am I going
with this? like Cstraub said, buy the rotating assembly w/ cast steel crk,
5.7 rod, and shorty piston, NOTHING IS CHEAP THESE DAYS! lucky you don't have to go thru 2 502's! small block stuff IS cheap, when you look
at it that way!











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