I have a completely stock 36hp prodrive and am very pleased. I live in an area where I have only seen 1 other SD drive engine in the past 3 years of hunting and only about 3 longtails so if I get stuck or break down there is not a lot of options in looking for help. Reliability is more important to me than a couple of MPH increase at the top end. I can always get up 15 minutes earlier and get there first and there are so few mud motors in my area that I usually have my spots to myself anyway.
However, who doesn't want to do faster?!. I am not a mechanic but understand that pushing an air cooled engine beyond it's standard operating range likely has consequences. I have read many of the posts here that describe the increased amount of maintenance that appears to go along with modifying the engines for increased horsepower as well as seen some pictures of catastrophic failures. At the same time, I see some of the engine manufactureres (mainly mudbuddy) with all these engines claiming 40-50 HP range that come with the same mods people are doing themselves. Are these factory upgraded engines any more reliable than what people are doing themselves. I was hoping to hear from people with more mechanical experience than myself. Maybe garage mechanics are just pushing their engines too far, but if mud buddy is betting the next generation of motors on that outboard looking lower unit thing they came up with stating it is a 50hp, and apparently selling all these MB 5000, 7000 models and I don't hear many people complaining- are their upgrades actually designed better and last longer. I am not a particular fan of mud buddy (I have one of their longtails and cringe every time I have to call customer service for a part 'cause I know they are probably going to send the wrong thing and I will have to send it back twice) but they do seem to be selling a lot of these out-of-the- box upgraded motors. So, my long winded question is- are these factory upgraded motors as reliable as stock 35 or 36hp motors? If they are so great, why doesn't gatortail or prodrive offer upgraded engines on their motors as well?

A stage 1 (heads, cam, exhaust) upgrade will actually increase your engine's reliability.

Pro-Drive doesn't mod engines because they don't have time to do it.

Gator Tail doesn't do it because they don't have the time needed either. However, the GT production manager mods engines in his spare time, but doesn't really sell parts for do-it-your-sellers.

The reason they sell so many is because guys that don't have the know-how or are willing to DIY buy it already hopped up.

^ what he said x 2

Stock engines leave the factory with several flaws.

1. Most engines (almost all) have leaky valves which rob the engine of power.
2. The stock valves are 2-piece and are prone to failure which will destroy the engine if and when they fail.
3. The stock mufflers also cause lots of damage after being banged around. Commonly...welding slag will break free and travel it's way into a cylinder which also causes serious and mostly catostrophinc damage.
4. The stock cam shafts commonly fail due to worn cam lobes.

Once the engine is modified with performance parts...all of the above possibilities are eliminated.

1. Valves are sealed correctly with a 3 or more angle valve job.
2. Junk 2-piece valves are replaced with a stainless steel or titanium 1-piece valve.
3. Aftermarket exhaust eliminates the possibility of slag breaking loose and causing internal engine damage.
4. Aftermarket cams are made of stronger metal preventing them from failing/rounding lobes.

Thanks man

Tapatalk 2

Most problems I see on a Pd is cracked blocks and leaking case gaskets with a hopped up motor.

But when you do heads and a cam on the prodrive your Rpm are to high with a stock prop. If I were you I get some head work done and a muffler of choice.

With my heads decked .030 and a evt muffler I can run 4200 rpm all day. With a cam it would put me at about 4600. I'd need the hi rev coils


Also it seems that once you turn up more than about 4400 that the life decreases.

Glad you posted that up T. I've never really thought about that end of it.

Tapatalk 2

Cracked blocks and leaking case gaskets are caused by the same problem (bad design) and just as likely to happen with stock motors. Keep an eye on your case bolts.

You don't have to run WOT all the time. Just because a cam would put you on the rev limiter doesn't mean it's not a good add on. The bottom end performance is well worth the money. I modded mine to step a load, not to win races.

Again, you don't have to run WOT all the time. Do you run wide open everywhere you go in your truck? Use some restraint if you think the magic number is 4400.

Or back off the throttle...Running wide open throttle and trimming down to lower rpms is making the engine work harder than Trimming up to optimium range then backing off the throttle.