Can you make a 305 stroker with 350 crank and rods?

[bucket]

For a while (maybe still), there was a company that sold a stroker kit for the 305. It wound up being 334 ci I think. Speed-O-Motive maybe was the vendor?

 

[greyghost]

Wel technically you could make one. If ya bought a 383 stroker kit for a 350, and just put the longer connecting rods on the smaller pistons. And then have the crank balanced for the lighter assembly.
Its doable, but as you stated, would be a waste of time. I agree 350 is a way better starting point for "hopping up".

I disagree on the LS note. Cant stand the stupid things in anything other than what they came in from the factory.
They are great engines. They make good power, reliable, good mileage, easy to hop up, and nowadays with all the swap kits probabaly be pretty easy to swap, no disagreement there, but they're not for me. I want nothing to do with them personally. I'm old school, dont like computerized crap.

ah no, by changing rods , you need diff pistons with rod hole up higher or closer to rings, I'm pretty sure nobody makes them. just like 383, by changing crank in 350 , pistons wud come up outta cylinder 1/4" . head wud never bolt on, but since chevy performance made a crate 383, most top line piston manufacturers started making them, As far as I know only available in forged aluminum, wrist pin is open to oil ring thats how high up rod goes for flush head surface, but lotsa diff tops from flat to hemi shape, very lil skirt as piston comes down crank counterweights wud clip bottom, some blocks need modified for rod clearance on oil pan surface n some around camshaft area.Also cylinder bored out .030 over to get 383 cu. chevy performance block 383 has 3.80 stroke as they only sell new blocks, hence 4.00 bore x 3.80 =383 cu. 4.030 x 3.75 = 383cu. Totally understand the SB and LS thing. I was planning on a SB in '81 SWB , but just chance came across '04 silverado 5.3 ...4x4 w/toasted tranny, cancer everywhere, long story short, got whole truck for less than5 bills. Guy said it still runs , but i never heard it. even if it dont. great starting point still. good luck finding what your looking for...short block 350 w 4bolt main, your best n cheapest , cleanup 305 heads , take mini grinder, or dotco. open up intake ports to new gasket hole, same with exhaust ports, use finer stone to polish smooth, new springs, increase valve size if you have cash or just regrind by hand for new seal, lotsa great books on rebuilding SBC for a diy. n low budget be careful with having anything resurfaced, it changes intake angle surfaces n possible vacuum leaks around ports..

 

[Bennyt]

ah no, by changing rods , you need diff pistons with rod hole up higher or closer to rings, I'm pretty sure nobody makes them. just like 383, by changing crank in 350 , pistons wud come up outta cylinder 1/4" . head wud never bolt on, but since chevy performance made a crate 383, most top line piston manufacturers started making them, As far as I know only available in forged aluminum, wrist pin is open to oil ring thats how high up rod goes for flush head surface, but lotsa diff tops from flat to hemi shape, very lil skirt as piston comes down crank counterweights wud clip bottom, some blocks need modified for rod clearance on oil pan surface n some around camshaft area.Also cylinder bored out .030 over to get 383 cu. chevy performance block 383 has 3.80 stroke as they only sell new blocks, hence 4.00 bore x 3.80 =383 cu. 4.030 x 3.75 = 383cu. Totally understand the SB and LS thing. I was planning on a SB in '81 SWB , but just chance came across '04 silverado 5.3 ...4x4 w/toasted tranny, cancer everywhere, long story short, got whole truck for less than5 bills. Guy said it still runs , but i never heard it. even if it dont. great starting point still. good luck finding what your looking for...short block 350 w 4bolt main, your best n cheapest , cleanup 305 heads , take mini grinder, or dotco. open up intake ports to new gasket hole, same with exhaust ports, use finer stone to polish smooth, new springs, increase valve size if you have cash or just regrind by hand for new seal, lotsa great books on rebuilding SBC for a diy. n low budget be careful with having anything resurfaced, it changes intake angle surfaces n possible vacuum leaks around ports..

While there is much better combo's out there...I've been part of building 1 or 2 stroker 305's way back in the day. If I recall you can use an off the shelf low compression 305 piston with a 5.565 rod. I don't remember if we had to cut the skirts or notch the pistons for valve clearance but I don't remember it being that big of a deal. Being a small bore with potentially thick walls, it would probably be a good candidate to squeeze on.

Yes, you would have to rebalance and while 400 cranks are externally balanced, it doesn't have to stay that way. It was regular practice for street racers to build 383's and use an internal balance torsional vibration dampener so that you couldn't feel the weight when checking the competition. Most still used the external balanced flexplate as it was easier and nobody was going to pull the bellhousing and look.

While a 305 stroker can be done, just no real reason. The point is there is lots of combinations you can make using off the shelf parts and mismatching. Mopar 360 rods in Ford 351w as part of a 427 stroker, 454 crank in a 409w motor, etc. TRW2252 w/ short rod in a 383 stroker to keep costs down. I used to know a bunch, but it's been many years.

 

[greyghost]

While there is much better combo's out there...I've been part of building 1 or 2 stroker 305's way back in the day. If I recall you can use an off the shelf low compression 305 piston with a 5.565 rod. I don't remember if we had to cut the skirts or notch the pistons for valve clearance but I don't remember it being that big of a deal. Being a small bore with potentially thick walls, it would probably be a good candidate to squeeze on.

Yes, you would have to rebalance and while 400 cranks are externally balanced, it doesn't have to stay that way. It was regular practice for street racers to build 383's and use an internal balance torsional vibration dampener so that you couldn't feel the weight when checking the competition. Most still used the external balanced flexplate as it was easier and nobody was going to pull the bellhousing and look.

While a 305 stroker can be done, just no real reason. The point is there is lots of combinations you can make using off the shelf parts and mismatching. Mopar 360 rods in Ford 351w as part of a 427 stroker, 454 crank in a 409w motor, etc. TRW2252 w/ short rod in a 383 stroker to keep costs down. I used to know a bunch, but it's been many years.

I'm not sure what rod you used 3.48 is stock rod length. from center point wrist pin to flat surface of block can not change or lowering compression cause you cannot increase piston height without head interference. I dont know rod length in an OPAL , but I do know a friend who used 350 pistons in I4 opal engine, no idea what rods or crank in OPAL, had no idea it wud work, he said chevy pistons were better and cheaper than oem OPAL. other than that thats where my engine knowledge stops, strictly SBCmechanic, nothing bout vortec or LS designs. I'm hoping to change that in next 12 months.

 

[Bennyt]

I'm not sure what rod you used 3.48 is stock rod length. from center point wrist pin to flat surface of block can not change or lowering compression cause you cannot increase piston height without head interference. I dont know rod length in an OPAL , but I do know a friend who used 350 pistons in I4 opal engine, no idea what rods or crank in OPAL, had no idea it wud work, he said chevy pistons were better and cheaper than oem OPAL. other than that thats where my engine knowledge stops, strictly SBCmechanic, nothing bout vortec or LS designs. I'm hoping to change that in next 12 months.

I think you are mixing up the stroke and rod length.
350 stroke is 3.48, and all SBC's other than 400 are 5.7 rod length.

400 stroke is 3.75 and rod length is 5.565

A 0.27 increase in stroke, and a 0.135 decrease in rod length allows for a stock style piston to be used in a stroker. When I worked for PAW, we probably sold 25 stroker kits a week like this, probably 10-25,000 over the years, making it very popular kit.

You can use a 5.7 rod for street use to decrease side load, but requires custom, but very common piston.

You can even go to a 6.0 rod on a longer stroke for a race motor, but the wrist pin will be up in the oil ring land and a very short skirt so it's going to be noisy.

 

[Ricko1966]

I just had to pull this back from the grave.In response to the O.Ps post if you put a 350 crank in a 305,you get a 305 with a heavier crank and probably a balance problem. 350+305 are the same stroke

 

[AyWoSch Motors]

I just had to pull this back from the grave.In response to the O.Ps post if you put a 350 crank in a 305,you get a 305 with a heavier crank and probably a balance problem. 350+305 are the same stroke

Yeah, i found that out. Differnt bore.