540 BBC
 

I just ordered 2 new Dart Big M 4.500" bore, 9.800" deck blocks, and 2 pair of Brodix BB-2 Plus aluminum cylinder heads. With the 119cc combustion chamber and JE forged pistons it will work out to 9.0:1 compression.

Has anyone used the Brodix BB-2 Plus heads in a marine application? Is it necessary to hard anodize the heads in a freshwater (Lake Michigan) application?

With a 234/244, .527"/.544", 112 LSA hyd. roller cam, anyone think I would have reversion issues with Stainless Marine exhaust?

DD2000 predicts this:

RPM......HP......TQ
2000....245.....643
2500....314.....660
3000....374.....654
3500....430.....645
4000....480.....630
4500....513.....598
5000....523.....549
5500....503.....481
6000....462.....404

You can contact KAAMA. as he's had extensive experience with many different 540 variations.

Sutphen30,

I got the flow numbers from the the Brodix website. I've used Dart heads in the past with good results as well, I've got Dart 18* CNC heads on my Vette's twin turbo engine. However, the machinist I use, Fast Times Motorworks, recommended the Brodix over the Darts for smaller port BBC heads.

I'm not set on the cam spacs yet, that was just one that I was using for modeling. In any case, it will still be relatively mild. I'll sacrifice a few hp in return for increased reliability and lower maintenance.

Okay, I checked out the AFR 305's and at least according to their claims, they do have better intake and exhaust flow across the lift range. I'll have them order those instead.

Do you think Copper Beryllium valve seats are a good idea?

With the Crane 741 and AFR 305's, DD2000 predicts:

RPM........HP........TQ
2000......247.......647
2500......317.......666
3000......380.......665
3500......441.......661
4000......497.......653
4500......546.......637
5000......573.......602
5500......577.......551
6000......551.......482


Is this too much for Dollar Offshore prepped TRS and Borg-Warner Velvet Drives, assuming I'm easy on the throttles out of the hole?

According to the speed calculator on go-fast.com, assuming 8500lbs, these would be good enough for 82 mph peak at 5000 rpm, and 72mph cruising at 3500 rpm.

Could one of you computer guys run the same combination with Dart Pro-1 325's and Crane 651 cam on your DD. Cam specs. are 244,256 @ .050, .632/.632 lift. 114 sep. Thanks.

Here's the dyno sheets from my short deck naturally aspirated 540's on Tom Earharts dyno. Holley HP950's, Dart single plane intake manifolds, Dart Pro-1 aluminum 310cc heads fully ported by JimV with 2.30" intake valves and 1.88" exhaust valves, Crower hyd roller 236*/244* on 114* lobe seps, 9.6 comp ratio, 32* timing, full length tubular dry headers, MSD billet distributors, MSD Crank Triggers with Crane Hi-6M ignition boxes.

RPM TQ HP
1500 507 145
2000 545 207
2500 539 257
3000 614 351
3500 598 399
4000 662 504
4500 692 593
5000 684 651
5250 658 658
5400 655 673
5500 651 682
5750 639 699

Just got off the phone with Mark ( KAAMA )
Although the engines produce HP all the way up at 5750 RPM he doesn't run it above 5500 - 5600 MAX.
That is what JIM V. heads will get you.

Just think what these engines would produce at 10.5 to 1 compression and a more agressive cam.

And it would still run on pump gas.

Those are some startling numbers from a small set of heads. I'll have to call Jim V. this winter.

Monty, I have a 555 with the BB2 Plus heads with a bowl port. It has a mild cam (232/240 at 114 LSA) and MPI. Running 9.4 compression it made a little over 600 HP on the dyno. I now have over 200 hrs. on it with nothing but oil changes. I only turn it to a max of 5400 RPM.

Monty, if you don't mind, who did you buy the shortblocks from ? and how much were they ?

Monty, if you're currently running stock BW Velvet Drive transmissions you're going to need to upgrade to something like the Huber version as the stock BW units aren't built to handle the kinds of horsepower numbers you're looking at.

ttt

Good Gosh those are some tq monsters....666 ft lbs at 2500...yeouch. N/A and pretty conservative build up......Nice motors!!

Thanks for the information. Looks like there are severaln other healthy example already out there as well. Sounds like my expectations are in line with what you other guys have.

dlbCheckmate, I ordered the blocks and heads through Fast Times Motorworks in Morton Grove, IL. That's where I have been getting my machine work done for the past 5-6 years. They're mostly known for NMCA/NSCA and NMRA racing engines, but they do quite a few custom boat engines as well. I can usually get the same prices through them that you can get through Jeg's or Summit. $1999 for each block.

Woof, nice figures out of these motors. Any idea what Stainless Marine manifolds would do to these numbers??

Scott B

I'm hoping the Stainless Marine manifolds and risers won't hurt too much. If so, I'd guess moreso towards the upper rpm range so maybe the impact won't be within the normal operating range. As you can tell, I'm emphasizing midrange torque over upper end hp since it's a pretty heavy (8000#+) non-stepped hull.

My understanding is the SSM's do falter above 5200. Like you, I am building a low rpm torquey motor , so I hope we are right! :)

Scott B

Monty,
I had a buddy that used to work for Fastimes. He then moved to Sterling, then Katech, and now I think he is still at Earnhart enterprises (I forgot the real name, not much of a Nascar guy)
Man they have some seriously fast small tired street cars. I remember years ago a 64-65 El camino with a big dent in the quarter panel that ran 9:50's, it was a total sleeper.

Monty are you going to the C.O.P.S. run this weekend ? I'll show you mine if you show me yours ! Mistress that is.

I'd love to, but being as I took the engine's and tranny's out of the boat last weekend, I won't be able to make it this year.

I would love to check out your boat sometime, and if you're ever in the Michigan City/New Buffalo area, let me know. We can take a ride out to the warehouse where I store mine and you can see mine.

Keep an eye on the thread about the C.O.P.S. run over to Michigan City saturday and come over and meet us for lunch. The more the merrier. I find it pretty interesting what all you are doing to your boat. Been there done that. I'm running 540's and TRS. Rebuilt or replaced everything and I mean everything on the boat. If you want my cell # 765-506-0672 call me anytime. If you think you might meet us for lunch call me around noon saturday to see if plans changed because of water conditions. Catch you later. Doug

Doug,

Thanks for the offers. I'll keep it in mind, I've got some family and volunteer obligations this weekend so my schedule is kinda' tight.

Sounds like I'm heading down a path you've already traveled. I'd definitely like to get together sometime and talk boats.

540BBC + 3.3L Whipple
 

What would a 540 with 41 cam and AFR heads
8:1 cr and a 3.3L whipple at 5-6 psi do?
Any one done one?

^^And what would it do with 15 lbs of boost from twin turbochargers?

I ordered the remainder of the bottom end today. A pair of Lunati Pro-series 4340NT 4.25" cranks, Crower 6.386" 4340 billet rods, and JE pistons which will yield almost exactly 9.0:1 static compression ratio with the AFR's 119cc chambers.

The next issue is the intake manifold and carbs. There isn't much clearance between the top of the flame arrestors and the inside of the engine hatches as it is with the ultra-short cast iron intake manifolds, so even an Edelbrock Performer (Victors are what AFR recommends with these heads, not a chance they'll fit)will probably require me to remove some of the ribbing/bracing on the underside of the hatch covers, although I may be able to mill it down a bit. I know my wife wouldn't be too keen on doing away with the sun pad and adding scoops, so I may have to deal with choking the engines with the stock manifolds - worst case. Any ideas?

Last about 8 seconds at WOT before you need a shovel to clean the bildge. :D

^^ hmmmm, I have been runing a pair of 510 ci BBC with twin turbos at around 15 lbs all summer and only this past weekend did I damage an engine, and that was because of a dropped valve in my starboard engine.

Most of the innards of the engine were basically stock with some porting of the heads. I was running cp12 fuel at a 1:4 mix with 93 octane gas. Normally aspirated compression was about 7:1.

Got to believe with a beefier engine it would sing like a newly released canary. :)

Here they be:

Gayle Banks Turbo Engines

I have a 1987 38kv Scarab that will top out at around 77 mph with these engines.

I want to be in the 90s by next spring. A pair of beefed up 540s standard deck is what I am looking at, while still using the turbos, intake, top end.

Are my expectations too high? Is 95 mph a fantasy dream?

I also plan on upgrading the outdrives to a set of #5s or #6s unless someone convinces me the IIIa will work.
I would love to be able to spray a semi rooster tail with this thing, but I still want to be able to come out of the hole in a decent manner. External hydraulic steering gets added on also.

And of course something reliable (if that is even possible) would be nice! :D

I think someone said that they knew a guy who had a pair of 1000s and #5s on their 38kv and it was pusing 96mph on the GPS.

Don't mean to highjack the thread Monty. I am following your progress with great interest. At least trying to keep this topic punted to the top of the forum list!

Anyone out there with the experience to be able to steer me in the right direction as far as engine internals are concerned?

I've pretty much accumulated all the parts for my 540's, the only thing left is the camshaft.

I'm looking at two cams and the sfollowing is predicted by DD2000. Assuming an 8500# non-step with TRS/ BW drives (reliability is a concern and priority over top speed), which would you choose? Redline will be ~5000rpm.

................731.......................741
RPM.......HP.....TQ..............HP.....TQ
2000....255....670............245....644
2500....323....679............315....661
3000....386....675............377....660
3500....442....663............438....651
4000....496....651............496....651
4500....537....626............547....638
5000....557....585............581....610
5500....554....529............587....560

AVG......444....635............448....635

I'm leaning towards the 731, it's the smaller of the two, although both are relatively mild hydraulic rollers. The performance derived using either cam is very similar and the difference in boat speed would only be 1-2 mph which isn't that important to me. Obviously the smaller cam would have better throttle response, less chance of water reversion, etc but I wonder if it has too much low rpm torque for the TRS drives. The 741 cam is only advantageous during the last 1000 rpm or so of the operating range, worth maybe 2 mph top speed, estimated to be 80 mph vs. 82 mph on the go-fast.com speed calculator.

Monty, desk top dyno is not very accurate on the torque numbers below about 3500 RPM. Seems like I remember reading that it can't calculate in that range so it just plugs in numbers. I've found it to be very accurate at higher RPM. I've simulated several engines that were actually dynoed and pretty much confirmed the lower RPM torque numbers are way off. The 731 will definitely give you a lot of torque though. I would expect peak HP to be right around 5000 RPM in a 540 with a dual plane intake.

That seems to be true from my experience as well. I used DD2000 to "mock" up the last few engine's I've built and then subsequently dynoed them on Fast Times Motorworks' Superflow and the actual results were within 5hp/tq across the board, but unfortunately, most of these were relatively high performance engine's and the dyno would "grab" below 4000 rpm or so. As a result, I can't say for sure how accurate DD2000 is at low rpms either.

hey budah the spec sheet that came with my cam said 130lbs for my 139741 should i change i have the heads at the machine shop so now would be a good time to change

Monty,

You need to go back to my first post within this thread and read what a REAL DYNO TEST did with my 540's and the cams I used that are identical almost to the "T" compared to the 741 cam and fully ported aluminum heads with a Dart intake. In a heavy boat like a Cigarette I would definately use a good dual plane intake manifold. You are being wise and I respect you that you are at least considering the smaller cam---- it seems everyone always wants to install the largest cam they can get away with in an engine when they don't need it. I like the way you are really thinking taking into consideration of all your engine components---especially the cam! Your mindset is that you want reliability and dependability, good idling and drivability around the docks FIRST---not just speed and horsepower----although I will say that a 741 cam is still considered a somewhat mild cam for a 540 inch engine.

I have seen many guys who put really BIG NASTY cams in their engines that require high idles, fouling out plugs and can't even shift without the engine dying and they have ONE HECK OF A TIME when trying to manuver around the docks, boat traffic, wind and river currents. They suddenly don't look so cool anymore because they operate their boat with panic mode movements and over compensate...i.e. while trying to shift into reverse the engine dies and the boat is still moving forward towards another boat, seawall or other object that they are trying to avoid hitting. With the cams in my 540's (identical to the Crane 741 on 114* lobes) will idle at 800rpm in nuetral and what is really nice is that they will idle at 600-650rpm in gear for long periods without dying. :)

Hey Mark,
My big ol nasty cam idles at 700 in gear with no problems !:D

Now getting lifters to live is a whole other story !;)

Kaama,

Thanks for the reply. I'm new to boats, but I've been hot rodding for several years. I know I'll never be the fastest guy on the lake with the Mistress, I just want to be able to have decent performance reliably without all the headaches. To be honest, I'm wondering if I woulda' been better off just building a pair of decent 454's since even my mild 540's will probably push the limits of the TRS's. I'm even considering using the stock cast iron intake manifolds to intentionally detune(choke) the engine, as well as ensure it all fits under the stock hatches. If I am able to fit an aftermarke tintake, it'll definitely be a dual plane (although a pair of custom Hogan's sheetmetals would be trick - got one on the Vette). I've already got a pair of Performers that Too Old gave me.

One of the reasons I'm leaning towards the 371 is that the boat came with Stainless Marine manifolds and risers and I'd like to be able to use them for now. SM recommends cams with less than 230* duration in order to prevent water reversion. I haven't called them yet, that's just what they have in their FAQ's. I'll probably call them and see if they have an overlap recommendation rather than just duration. Their recommendation is probably based on a 110 or 112 LSA. A 114 LSA would generally provide a relatively broader and flatter torque curve while allowing a little more duration with less overlap compared to a narrower LSA cam.

BTW, I looked back over your first post as you suggested and noticed you've got a "hole" in your torque and hp curve at 3500rpm - at 3000 it is 614tq, 3500 is 598, then 4000 is 662, and your hp makes a 105hp jump from 3500 to 4000 rpm. Was that a typo or just tuning? The math works out, (598 x 3500)/5252 =398.5, so I was just wondering. Big mechanical secondaries coming on, or just eh dyno starting to grab?

Chuck,

I am mainly speaking about guys I would see back in the 1980's who didn't know better back then or who were ignorant about cams durations for marine use and just wanted to go fast. You on the other hand have done your home work and know better.----Besides, if your cam is idling at 700rpm then I think most would agree it really isn't too big and you have made a good selection for your engine! :D

Mark,
Thanks for the complements. And I thought I just got lucky !

Hopefully with Budah's help and a new camshaft I can get the valvetrain a little more reliable. As I've learned snowmobiling and now finally it's sinking in on the boat , RELIABLITY is the key word.

Monty,

NO---that was not a typo! Actually/honestly, I was going to go with a smaller hydraulic roller cam too---BUT Crower accidently sent me the wrong (larger) cams! I originally ordered a pair of 232*/240* cams from Crower, but they sent me the 236*/244* cams by mistake and my engine project was WAY BEHIND so I knew they would still work well,------I almost sent them back because I was a little HOT :hothead: about it, but I decided to installed them anyway.

BTW Monty,

I think if I would have had a dual plane intake on my engines instead of the Dart single plane that hole in the torque would have not even showed up!