TUNING a 540 ***warning, boating content***

[rivermobster]

Going to be helping my friend with his Stoker this winter...

JMS will be turning his blue 502 into a 540.

What's the best option for this, tuning wise, to get the most out of this new build? New throttle body? New injectors? Send out the stock ECU? To who?

Thanks in advance for the suggestions.

 

[ChrisV]

picssssssss

 

[lbhsbz]

sell it and hang an outboard off the back... It's a Stoker.

 

[Gelcoater]

Going to be helping my friend with his Stoker this winter...

JMS will be turning his blue 502 into a 540.

What's the best option for this, tuning wise, to get the most out of this new build? New throttle body? New injectors? Send out the stock ECU? To who?

Thanks in advance for the suggestions.

Finally!
A thread someone isn’t complaining in.
Thanks Joe

Post up some pics.

 

[DaveH]

Going to be helping my friend with his Stoker this winter...

JMS will be turning his blue 502 into a 540.

What's the best option for this, tuning wise, to get the most out of this new build? New throttle body? New injectors? Send out the stock ECU? To who?

Thanks in advance for the suggestions.

IMO the BEST option on something like this....assuming you will be making significant power upgrades.....ditch the merc ECU and put an aftermarket live tune system on it. run any sensors, injectors, ignition you want, including wide band, and have easy access to logging and real time tuning.

 

[bonesfab]

put a holley Hp on it. Thats what I plan to run on mine when I do it. I just did two different boats for friends with them.

 

[bonesfab]

Sending it out for a can tune is never 100% right. Too many variables. Might need injectors depending on power level.

 

[Bigbore500r]

Going to be helping my friend with his Stoker this winter...

JMS will be turning his blue 502 into a 540.

What's the best option for this, tuning wise, to get the most out of this new build? New throttle body? New injectors? Send out the stock ECU? To who?

Thanks in advance for the suggestions.

Is it starting life as a 500efi?

If so - it has a decent intake on it already. Its similar to a 525efi but with iron heads.

The 502 EFI's run great swapping to edelbrock RPM marine heads and tuning. Hopefully you are including some good heads in the build, the stock GM rec port iron heads aren't that great, not worth rebuilding or modifying VS quality aluminum offerings

Not sure if anything needs to be done to the intake to maximize your added cubic inches though.....or your intended RPM range if its gonna sing past 5500. They make a bolt-on mono blade throttle body that will help it breath, the stock one has twin 58mm bores and gets restrictive. Id check that out.
Tyler Crockett has some good info on stock intake mods - might give them a call.

If its starting life as a 502 MAG (black efi motors) - those need major help in the intake and TB department - those run a GM 90's 7.4L truck intake basically and roll over and stop building power in the 4000rpm range. My friend had a 540 built out of his 502 mag. Had the stock intake "ported" and had it cammed. Imco powerflow manifolds / elbows. It definitely made more power in the midrange but that intake and TB choked it badly up top. So badly, that it couldn't swing a bigger prop past 4000, pretty much negating any speed gain......now thats DEPRESSING. Dont be that combo !



No Idea on tuning, Dustin @ Menace has a good resource I think. I can tell you there are alot of bad "tooners" out there....beware!
Since it's an older motor I think it runs a MEFI-4, which is old school but robust and easily tunable by pretty much anyone. They didn't go 555 Motorola till later, so I would stick with the MEFI unless you just wanna chuck more $$$ at the build

 

[River Runnin]

Just go Fooking Electric! All these other Morons are going that way!

 

[rivermobster]

sell it and hang an outboard off the back... It's a Stoker.

22, not a 20. He already had a wacker Stoker.

 

[rivermobster]

IMO the BEST option on something like this....assuming you will be making significant power upgrades.....ditch the merc ECU and put an aftermarket live tune system on it. run any sensors, injectors, ignition you want, including wide band, and have easy access to logging and real time tuning.

Nothing significant. Mild cam, a bit more compression, and the topic of aluminum heads has been repeatedly discussed but not decided on yet. This will probably be a November build. Jury is still out.

Your thoughts on the heads??

put a holley Hp on it. Thats what I plan to run on mine when I do it. I just did two different boats for friends with them.

Wanna do another one in Nov/Dec?

 

[rivermobster]

Finally!
A thread someone isn’t complaining in.
Thanks Joe

Post up some pics.

You've seen the pics. Looks exactly like every stock blue merc 502 out there!

I think I'm gonna have Detail Dan do the R&R we discussed. He has an in house gel guy now he says...

 

[lbhsbz]

22, not a 20. He already had a wacker Stoker.

22s need a V8 OMC from Monte…

 

[rivermobster]

22s need a V8 OMC from Monte…

There used to be a red stoker back in the day, that had a wicked azz V8 on it. FUCKING FAST!!!!

He lined up with some guy with a flat, right at the dam, headed south, and smoked that flat from right off the line and the flat never caught up.

VERY impressive for sure.

 

[mjc]

Nothing significant. Mild cam, a bit more compression, and the topic of aluminum heads has been repeatedly discussed but not decided on yet. This will probably be a November build. Jury is still out.

Your thoughts on the heads??



Wanna do another one in Nov/Dec?

what ever you plan on using I would start ordering it now stuff seems to be hard to get some of those parts.

 

[rivermobster]

what ever you plan on using I would start ordering it now stuff seems to be hard to get some of those parts.

Already handled.

 

[sintax]

Nothing significant. Mild cam, a bit more compression, and the topic of aluminum heads has been repeatedly discussed but not decided on yet. This will probably be a November build. Jury is still out.

Your thoughts on the heads??



Wanna do another one in Nov/Dec?

Just do the Alum heads...

Whats going to happen is you're going to say "well that price sounds kind of expensive", so you end up trying to keep the GM irons, you put money into new valves, new hardware, new 5 angle valve job, they're bound to find a few cracks that need welding, then they say "so if you want, we can do a light fluff and buff on these ports and that sounds alright, and the next thing you know you have 2/3 the cost into the old iron that you would into a set of alum.

dont ask me how i know...

 

[SBMech]

If you're doing this for a big bump in power, do it right. Aluminum heads, port/polish with a plan for the injection/ignition going into it, that way you have a decent chance at a "Budget" .....spending 10k for 100hp when you wanted to spend 8k for 200+ is a tough reality sometimes that can be avoided with planning.

It's a boat so most likely you'll be 20k into it for 200+hp but at least you'll hit your goals....

Nothing worse than ending up with a frankenstein that you'd have been better off blowing the money on hookers and blow.....

 

[lbhsbz]

what ever you plan on using I would start ordering it now stuff seems to be hard to get some of those parts.

You seem surprised?

 

[mjc]

You seem surprised?

Not me rebuilding my 72 chevelle wagon, some stuff is easy other parts are a pain and realllllllly slow to get. Rubber door bumpers have so far been 3 months with no end in sight.

 

[bonesfab]

Not me rebuilding my 72 chevelle wagon, some stuff is easy other parts are a pain and realllllllly slow to get. Rubber door bumpers have so far been 3 months with no end in sight.

Welcome to my world times 10.

 

[lbhsbz]

Not me rebuilding my 72 chevelle wagon, some stuff is easy other parts are a pain and realllllllly slow to get. Rubber door bumpers have so far been 3 months with no end in sight.

I meant to quote him on the V8 whacker mopping up the flatty.

 

[DarkHorseRacing]

Aluminum heads all day long. Those cast iron heads don’t belong on a boat motor. Every performance builder will tell you that.

 

[mjc]

Welcome to my world times 10.

speaking of that where is my dash?

 

[rrrr]

Is it starting life as a 500efi?

View attachment 1150635

Not sure if anything needs to be done to the intake to maximize your added cubic inches though.....or your intended RPM range if its gonna sing past 5500. They make a bolt-on mono blade throttle body that will help it breath, the stock one has twin 58mm bores and gets restrictive. Id check that out.
Tyler Crockett has some good info on stock intake mods - might give them a call.

No Idea on tuning, Dustin @ Menace has a good resource I think. I can tell you there are alot of bad "tooners" out there....beware! Since it's an older motor I think it runs a MEFI-4, which is old school but robust and easily tunable by pretty much anyone. They didn't go 555 Motorola till later, so I would stick with the MEFI unless you just wanna chuck more $$$ at the build

I had a 540 that pulled 680 HP on the dyno. The builder had a source that cut an Arizona Speed and Marine intake apart, did the internal modifications, and rewelded it.

The engine ran on a MEFI 4, and as you said, tuning it wasn't difficult. This was my first experience with an EFI engine in a boat, and it was a good one. It didn't matter if the engine was hot, cold, had been thrashed hard, or sat for a month or two, it fired up with a twist of the key and ran perfectly.

 

[caribbean20]

I ran Dart aluminum heads on my last 502 build. Was very pleased.

 

[Mcintyrelocal]

Going to be helping my friend with his Stoker this winter...

JMS will be turning his blue 502 into a 540.

What's the best option for this, tuning wise, to get the most out of this new build? New throttle body? New injectors? Send out the stock ECU? To who?

Thanks in advance for the suggestions.

I would call Ben at EFI University in Havasu. He can help you through the whole process of using what efi you have or what changes you should make, and also has A dyno and can help tune it for you guys.

 

[rivermobster]

I ran Dart aluminum heads on my last 502 build. Was very pleased.

There are only a couple of options for heads where the exhaust ports are Not relocated.

They Have to stay in the stock positions for this build.

 

[port austin pirate]

brodeck, edelbrock or dart all good

 

[rivermobster]

brodeck, edelbrock or dart all good

I knew about the first two. Didn't know Dart had the option as well.

 

[Flying_Lavey]

brodeck, edelbrock or dart all good

I knew about the first two. Didn't know Dart had the option as well.

Kinda related, but what do you guys feel about AFR's?

 

[mattyc]

Kinda related, but what do you guys feel about AFR's?

Compile a list of head options, sounds like you dont want the raised exhaust port, look at available port size and flow rates and choose the best option that fits the budget. Are you concerned about exhaust alignment if you were to use heads with a raised exhaust port?
@rivermobster

 

[Runs2rch]

There are only a couple of options for heads where the exhaust ports are Not relocated.

They Have to stay in the stock positions for this build.

Brodix. Barry just did that write up with them.

 

[rivermobster]

Compile a list of head options, sounds like you dont want the raised exhaust port, look at available port size and flow rates and choose the best option that fits the budget. Are you concerned about exhaust alignment if you were to use heads with a raised exhaust port?
@rivermobster

Exactly.

Brodix. Barry just did that write up with them.

Those are the first choice being discussed.

 

[Bigbore500r]

I had a 540 that pulled 680 HP on the dyno. The builder had a source that cut an Arizona Speed and Marine intake apart, did the internal modifications, and rewelded it.

The engine ran on a MEFI 4, and as you said, tuning it wasn't difficult. This was my first experience with an EFI engine in a boat, and it was a good one. It didn't matter if the engine was hot, cold, had been thrashed hard, or sat for a month or two, it fired up with a twist of the key and ran perfectly.

I believe the AZ Speed and Marine intake is basically the Merc 525 intake.
My bastard child Volvo 415DPX has that style intake stock from Volvo, and the part number is an AZ Speed & Marine #

 

[Bigbore500r]

@rivermobster

Here's the pisser.....

 

[Flying_Lavey]

Compile a list of head options, sounds like you dont want the raised exhaust port, look at available port size and flow rates and choose the best option that fits the budget. Are you concerned about exhaust alignment if you were to use heads with a raised exhaust port?
@rivermobster

I have no idea if I'm going to be in the market anytime soon at all, I'm just more curious about the opinions on quality from those that are far more well versed than I in the subject.

 

[mjc]

Edelbrock does has the best aluminum foundry in hemet for making cylinder heads. They actually make most of the aftermarket heads for other manufactures. They make the GM aluminum heads there.

 

[DarkHorseRacing]

AFR are good. Teague uses AFR almost exclusively on his top end motors. His lower engine packages make do with Brodix.

We ran Brodix heads for years and the only issue we ever had was bad gas popped a valve seat. But that wasn’t a Brodix problem.

Both Teague engines we have now are AFR and they are rock solid.

 

[rivermobster]

@rivermobster

Here's the pisser.....

Yeah not really. The engine is tired and needs to be rebuilt anyways. And then adding a ProCharger on top of that??

Plus it won't fit. Not happening.

The boat was built to have a Whipple added later. We did a Ton of homework on going that way, but eventually decided against it.

I've driven Mike's stroker engines in multiple builds. He Knows how to make Dependable power with them.

This boat should go Another 20 years, maintenance free, with the 540.

 

[Bigbore500r]

Yeah not really. The engine is tired and needs to be rebuilt anyways. And then adding a ProCharger on top of that??

Plus it won't fit. Not happening.

The boat was built to have a Whipple added later. We did a Ton of homework on going that way, but eventually decided against it.

I've driven Mike's stroker engines in multiple builds. He Knows how to make Dependable power with them.

This boat should go Another 20 years, maintenance free, with the 540.

I didn't say run the tired motor...

A boosted 502 will net you bigger gains than running an N/A 540 in marine trim.

 

[rivermobster]

I didn't say run the tired motor...

A boosted 502 will net you bigger gains than running an N/A 540 in marine trim.

I've installed the ProCharger on a Raptor for a customer.

It was beyond unreal when it was all done.

 

[Bigbore500r]

I've installed the ProCharger on a Raptor for a customer.

It was beyond unreal when it was all done.

Did you take it off any sweet jumps?

 

[rivermobster]

Did you take it off any sweet jumps?

Negative ghost rider. Not many jumps in El Monte!

 

[NeedlesRat]

Can we please get pics of the Stoker??

 

[rivermobster]

Can we please get pics of the Stoker??

Don't have any on my phone. Sorry.

 

[port austin pirate]

arf are good, just for the record the Merc 525 alum heads are edlebrock though as i said before merc had them put a non gm stock bolt pattern on the exhaust so a standard chevy bolt pattern header wont line up

 

[Teague_JR]

just use the edelbrock marine 310's... if you are keeping the stock intake going bigger or more expensive on heads wont do much with the stock intake runner length. Use a monoblade 525 style throttle body like the AZ Speed one.

I also vote holley EFI rather than messing with the MEFI 3

 

[UltraLucky]

Going to be helping my friend with his Stoker this winter...

JMS will be turning his blue 502 into a 540.

What's the best option for this, tuning wise, to get the most out of this new build? New throttle body? New injectors? Send out the stock ECU? To who?

Thanks in advance for the suggestions.

Mike at JMS refreshed an old LS6 Mark IV for me and swapped in a hydraulic roller cam recently. Added my Holley HP EFI and had Brian at EFI Store/ Horsepower Connection tune the setup on the water. Great people to work with and the Holley setup when tuned right is hard to beat.

 

[rivermobster]

Mike at JMS refreshed an old LS6 Mark IV for me and swapped in a hydraulic roller cam recently. Added my Holley HP EFI and had Brian at EFI Store/ Horsepower Connection tune the setup on the water. Great people to work with and the Holley setup when tuned right is hard to beat.

I worked there for five years and I've known Mike way longer than that. They definitely build some good stuff!