Off the shelf cam options for marine engines
02-15-2016, 05:18 AM
#141
Registered
The 55mm cam was $550. Which doesn't bother me at all. It's the $4200 on the AFR heads that I could shoot myself for buying. I personally never really cared for there heads. I think they are around 25-30 hp less than some other heads out there. I think they are a good casting but Brodix has it all over them in that department and Brodix offers a anti-corrosion coating that they warranty for 7 years. And I can tell you a whole summer of 900hp through a set of exhaust ports and the coating looks untouched.
02-15-2016, 05:42 AM
#142
Registered
02-15-2016, 07:56 AM
#143
Banned
Join Date: Feb 2016
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Thanks Scott, and thank you for contributing tech in TECH forums as well. I owe Chris Straub and you an apology for interactions we have had in the past on here. I was given misinformation about both of you that caused me to form an unfair opinion. Hopefully this place can get back to being about engines, and the free sharing of information. Cheers
02-15-2016, 08:14 AM
#145
Banned
Join Date: Feb 2016
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
this thread has been a good one with a lot of good information.lets not fuk it up and get it locked or removed.also,imo if you have 16 lifters in a engine and one fails[colapse]soon after startup i think the problem is that lifter,not the cam lobe.i had this happen on 3 different engines on the dyno,twice with 5w30 oil.all 3 had different cams.bck,throw all 16 of your old lifters in the trash.they can only cause you problems that you don,t need.jmo.
Our return rate on 4603 morels for inspection was a total of 4 sets last year. That represents .011% of the sales of that part number returned. When PAC racing springs wanted to sell lifter for LS engines. They bought a set from every mfg. All of the lifters went through extensive testing. PAC only puts Morel in their catalog. The LS, the BBC, the SBC all use the same body from Morel. The only difference is the tie bar. If I put all the returns of these 3 lifters together I am at .007% in returns for the year of 2015.
There is no wide spread issue with Morel. There is an issue that Morel does not have that many direct accounts and is not adding any BECAUSE they can not keep supplied the accounts that they do have currently.
02-15-2016, 08:23 AM
#146
Banned
Join Date: Feb 2016
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
With any engine build there are compromises, even more so with a marine engine. Budget, octane, sustainable rpm, maintenance intervals, wet exhaust, idle rpm and quality, etc. Given these are constants for most end users, and the basic architecture of the BBC, there isn't a lot of latitude when choosing valve events. If you look at cams that have proven to work well in this environment, you'll notice a trend. The cams that I have had failures with, and not all of them had issues, have ranged in size and application. Even mild custom cams with low lift have caused lifter tie bars to break off from wacky harmonics. This is most likely not a result of the actual valve events, but the overall shape of the lobe. There is some pretty serious math involved in designing a stable lobe. Duration in cams for these marine applications is fairly consistent, and its easy to get close to your target rpm based on the cubes, and quality of the cylinder heads. The biggest gains in power in the last seven or eight years has come from cylinder head design, not cams. When you try to add a bunch of lift to take advantage of potential airflow in these killer heads, but need the smaller duration to stay in your rpm window, it can be very hard on parts, can ultimately make less power do to instability, and will be difficult to tune..
To do the above one must use cylinder head cross sectional area best suited for maximum performance in the mid range. Large heads make HP, they do not make torque nor due the tend to make wide flat powerbands. The industry if very guilty of marketing "Bigger is Better". This naturally feeds the male ego, but in reality can lead to disappointment in the end.
I think it is key to build for average power.
02-15-2016, 08:32 AM
#147
Banned
Join Date: Feb 2016
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
MASS, a hyd roller is heavy. We went to recommending 7/16" pushrods for most BBC builds with hyd rollers with lobe lift .365" and greater when using the Morel 4603 lifter. On SBC and LS engines we recommend 3/8" stuff.
Rockers arms can be an issue also. I work with ATK's Performance division and they have found changing rocker mfg can get rid of a lot of valvetrain noise in some cases.
02-15-2016, 08:41 AM
#148
Banned
Join Date: Feb 2016
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
If a shelf master is use there is no up charge and there is normal turn around time. To have a completely new master generated runs from $100 to $200 per profile. So a cam with a new intake and exhaust would cost you $200 to $400 for engineering the the cost of camshaft. This would run around $800 to $1000 per camshaft for a BBC.
02-15-2016, 08:42 AM
#149
Registered
Join Date: Jan 2009
Location: Metamora MI
Posts: 720
Likes: 0
Received 0 Likes
on
0 Posts
I have a very similar build. My motor started as a 502 Mag. Had it rebuilt by Champion Performance last year. Now it is a 509 7 lbs. Boost Procharger with 525 cam. I remember when the builder recommended the cam. In the back of my mind I was thinking why not a custom cam? I went with the Builders recommendation as he obviously knows a lot more than me about motors. Glad I did.
Last edited by hadleycat; 02-15-2016 at 09:03 AM. Reason: spelling
Gold Member
