Scroll down to the 540 part number 8m0113304 Merc reman guide and parts guide. that 540 is listed at 450 hp and rpms range is 4600 - 5000 rpms and max rpms is 5000 It is a brand new partial engine almost complete

Also all T bolt V modules rev limited 100 rpms over max rpms

Like I said that company whom is posted that miracle 80 hp gain and rev limits at 4600 is a sweet marketing talk.

10 hp increase at WOT 5000 rpms per Merc listing - 8M0113304 and I can buy all these engines thru Merc / Merc reman. Just saying link of the engines

The 540 with 440 hp and WOT is 4600 part number is 8m008599 is what you have from your post. remaned engine

https://embed.widencdn.net/pdf/plus/...n.pdf?u=orhjei

here is the specs thru Merc -- 540 brand NEW 450 hp 4600 thru 5000 rpms max brand new block and heads. Cast iron heads I almost sure thru Dart. This engine build is fairly new thru them within a year if I recall.

https://p.widencdn.net/koh7wg/540-Br...e-Engine-450HP

I realize its not exactly the same but there is many parts that is shared here.

The 450 hp --- 4600 - 5000 rpms engine has a New block - new Dart heads - roller rockers and so on and its only netting 10 more hp was basically my point to show that 540 inwhich carries 400 more RPMS . 4600 - 5000 rpms .

Also you can get the 440hp remaned in a longblock form as well.

Also for the record the 440 hp reman and the 450 hp new and the 440 hp longblock are listed under Mercury Racing as replacements for hp 500 and hp 540 REPOWERS

how much? $18k each?

The 440 hp reman drop complete retails for 19,306 . I had to look it up because I forgot and I seen Michigan Motors whom always wants people to think they are giving out great deals lists it at almost 22 K retail but selling for almost 19 K.

Common on their part to make all think wow what a great deal they are giving out online. Laughable when full retail is 19 306. Plus they have great support as well. Right if you believe that one to. Never drank their koolaide

And for the the ones selling this engine at 16 K good luck for them because they are NOT making anything from doing so, not one dime. The heros in the industry. Seems like there is many of them around. Not good for the industry period because after the sale you are completely on your own period.

https://www.michiganmotorz.com/mercr...hp-p-4324.html

Sorry to bump an old thread. I am interested in additional experiences with the merc 540 carb plus engines. Part # 8M0085999. I have them in my new to me Formula 370ss. They were installed by the former owner after hurting the 525EFI's. I repropped the boat and have it running pretty well but I'm trying to find some HP without sacrificing dependability. I looked into exhaust but was told I wouldn't gain much by EMI. The carbs were setup horribly wrong from MerCruiser so i rejetted them for last season and now have them getting wetflow tuned. It seems like getting 4-600rpm should be easy swapping the ignition but maybe the valve train should be improved first? roller rockers and heavier springs could be done in the boat? TIA

I have no experience on these engines, but I think it’s pretty safe to say that the valvetrain can handle another 4-600 rpm. The 502 MPIs could run 5k rpm all day long with stamped rockers and tiling springs (the cam though was really small for a bbc). I’d say run it with the higher rev limit before tearing into the top end.

I know it's an older thread but any body who had these motors, what did you think of them?