FormulaBoat

iTrader: (1)

Hi all, been a while since I've been here. Doing a 6.2L build for my boat, but the LS engine knowledgebase on this auto forum is immense, so thanks for the help.

What is the current perception of stroker kit longevity? Have read a lot that when they first came out, piston skirts were short lived, but that has since been resolved with revised piston architecture? Picking up one of the $1350 LSA warranty yanked blowers this afternoon from the classifieds on this forum (guy is local to me, hopefully it is OK), and considering to run E85 fuel exclusively. Have the entire lake to suck heat from the lid brick.

Would enjoy hearing opinions and advice on the subject, especially from anybody that is or has been daily driving a stroker setup for years. I use my boat every weekend in MI summers, for about 7 hours per. Don't want to have excessive oil consumption by the end of the first season or be putting pistons in it every 1-3 years because the skirts are getting skinny.

Thanks.

G Atsma

Since you are using a blower, why not rely upon it for the extra needed power rather than more cubes? Want more power? Adjust pulley sizes. That simple.

99 Black Bird T/A

iTrader: (4)

I'd skip the stroker kit if going Forced Induction. Just bump up the boost slightly to make up for extra cubes. Ultimately theoretical longevity will be higher with less wear, tear & strain plus you'll be able to spin more rpm if desired etc.

I have two 4 inch strokers a NA 383 LS1 in a 91 RS Camaro & a NA 416 LSA in a 99 Trans Am, both are trouble and issue free. Either can be used as a daily driver and sometimes the 383 LS1 is for a while. Key is correct piston selection and a high quality engine builder vs a monkey slapping parts together.

Durability with good maintenance and regular oil changes - its reasonable to expect 50,000 to 60,000 miles from an NA stroker with moderately hard use before a refresh is needed. Some engines go much longer - example one LS1Tech member had a sleeved stroker that went ~170,000+ miles back in the day.

old motorhead

iTrader: (10)

As mentioned above, leave the stroke stock. You can have a 500 cubic inches and not make a whole lot more power vs a 376. Torque will come in earlier but that's about it. You have a 1.9L blower and that's the limiting factor. As long as you don't over cam it, torque will be there in spades just past idle even with a smaller engine. The thing should jump out of the water. You can even get a fat boy on ski's out of the water easily....unless you jerk his arms off...

LLLosingit

iTrader: (4)

Boats work an engine harder than any other form of motorsports, Constant load and sustained RPM, Hell just your 7hr excursion probably put more wear on the engine then most see in weeks of daily driving. Honestly I would do some reading on the boat forums and see what they have experienced.

wretched73

This is the biggest point and should be OP's biggest concern

FormulaBoat

iTrader: (1)

Thanks for the input. The "LS" engines are somewhat rare in boats, and even more rare to find them modified in such, hence my asking here where they are toyed with in quantity, and every combination tried 100's of times over again. The knowledgebase here is immense. It seems the general consensus of the 4 responses so far is that an LS stroker kit is likely not going to possess the same longevity as a stock stroke LS engine. Given that, I'm on the same page as dialing in the required power level via boost vs cubes. Quality calibration, quality parts, detonation resistant E85, and should be stout for the long run.

Yes, marine engine load is similar to a vehicle going uphill continuously. The mildly built SBC I previously assembled for it ran a solid 15 years in the boat with only oil changes, etc. It is finally now getting tired and showing oil consumption and blow-by, but she has provided thousands of hours of reliable high performance pleasure in my 16.5' Formula, MerCruiser sterndrive. 52mph stock 4.3L 4 barrel, 67mph with the cam'd 350 Vortec I swapped in long ago. Now shooting for 70mph with the replacement 6.2L.

The LSA blower I looked at did not pan out, going to view another today on lunch. Request for stroker longevity advice was due in part to the desire to purchase a forged crank and pistons for a reliable blower build, then upon doing so is not much of a cost up to increase displacement via stroke change. If I can't find a decent used LSA supercharger locally, this engine may just as well end up as a carb or injected NA with a 226 duration cam or less (as advised by the exhaust manifold makers to prevent "reversion" which is sucking of exhaust cooling water backward into the ports @ idle). But even that should out-power the now tired SBC which is in it currently.

Thanks for all of your comments, they are valuable via your experience. Still an open ear for any high mileage stock-sleeve stroker builds.

FormulaBoat

iTrader: (1)

wretched: Correct, it is. Basically planning a build similar to driving a car uphill continuously for 150,000 miles with rock solid reliability. Fun and interesting challenge. Add as much performance as you reasonably can, without taking away from the longevity goals. I did hit it with the SBC build I did previously for it, just wanting to repeat that now again with a 6.2L. I target things like inconel exhaust and stainless intake vales, steel roller rocker arms (LS ones are fine), etc.... No aluminum rocker arms or hollow stem valves kind of thing. Needs to go the distance. Build it like it is going to the moon, or like you are never allowed to open the hood again after install.

FormulaBoat

iTrader: (1)

Update, picked up a decent used LSA blower today, so the squeeze is on. Will stay stock stroke unless somebody can convince me otherwise. Thanks.

wretched73

The longevity of your SBC is very impressive

I think you are going to be very happy with stock stroke and the LSA blower. When you, inevitably, max out the LSA blower more fun can be had with just a bigger blower or a turbo and stock stroke

G Atsma

Let's hope it puts you under the right kind of pressure.....

LLLosingit

iTrader: (4)

I run a stock stroke 6.0 with LSA supercharger on E85, Power wise you'll be way ahead of the cammed 350 Vortec and at a much lower RPM, They are torque monsters.

old motorhead

iTrader: (10)

Now, once you get your engine combo all dialed in, one more variable to sort through. Proper prop with just the right amount of jump out of the water along with a good top end. Maybe you can find someone with a similar setup. Chasing just the right prop can be a bitch sometimes. As I was about to drive off with my "new" bay boat, the previous owner warned me not to try to try a different prop.....as he'd tried 6 of them to get it right. It was a 22' Pathfinder with a 200 Yami HPDI. It got on plane easily and did 55mph with a light load. He did get it right.

psicko

If it were me, I would have the stock crank snout machined for double keyways 180 apart, and do the same for the balancer.