1987 454 mag 330hp??
 

I have a 87 454 mag 330 hp and would like to have around 425hp. I am told that my heads are the main problem. Are these peanut heads? Is that true? The engine has around 400 hours. Money wise would it be better to get a new engine or work on this one. I just dont want to nickle and dime this engine when it seems I can get a new one for 5-7k. I was thinking new alum exhaust manifold/ marine alum perfomance heads and alum intake. Seems like around $2500 just for all the parts. Would this put me around 425 hp?? I have done alot of work on a top end of an engine, but I do not have any exp on a bottom end. HELP!!!

You would be better of starting with a hi performance engine. The 330 is kind of a low end station wagon type of engine with a 2 bolt main block, cast crank, cast pistons and 3/8 rod bolts in the connecting rods and yes, your heads are not great. If you could find a reasonable priced running 454 Magnum (365 HP) that would be a great start for a freshening and upgrades. The issue you may run into is your outdrive... if it is an Alpha One you will need to be nice to it with more HP. Good Luck.

Not true, my 1989 330 HP is a 4 bolt. Yes, it has peanut heads, an upgrade to the heads and an intake and Holley 850 Vacuum secondary marine carb would be good for the #'s you are looking for. Change the cam as well and you can get 600 HP without too much trouble. I am now running 500 cubic inch blown w/ Canfield aluminum heads and over 900 HP out of that same 330 HP block from 1989. It is a great 4 bolt base to work from. P.S., did I say that I have all that 600 HP stuff that I have replaced with the new blower set up? Right here in my garage? Lunati roller cam for a Gen 4 & lifters, Weiand Intake, World Products Grumpy Jenkins large oval port heads and an 850 Holley Vacuum secondry marine coast guard approved carb, Holley Marine Coast Guard approved high volume fuel pump, stainless monster flame arrestor. And, oh yeah, it made 600 HP. It's all here in So. Cal collecting dust my man.
949-701-0900 Greg.:ernaehrung004:

Thanks for the help.. Greg, I may be giving you a call in a couple months in you still have the parts. I am going to start a rebuild this winter. Thanks
Brent

large oval heads are the best for boating RPM's. Match that with an edelbrock RPM Air Gap and a 800 holley. Exhaust is ALWAYS a good purchase...

I had twin 1987 330 hp 454's. Installed a slightly more agressive cam, mild pop up pistons, MSD supplement to Thunderbolt ignition, epoxy coated Edlebrock RPM Performer intake, and marine Holley carb. Dyno #'s for both engines were very close and they read 424 hp & 509 ft/lb torque. The dyno was by Owens Racing in Houston and they were impressed by the little heads that could! The peanut port heads can produce some serious torque. Tommy

Dual plane manifold builds more velocity at 5200 than a single plane intake.
BOATING= TORQUE.... HP is RPM . Build engine for max torque between 4000 and 5500.
I dont care about HP I want to see what the engine can do,Torque wise, at 5000(5250).

Just my .02

No sweat Brent, It's a good block you have. I may be putting the stuff on E bay soon so if intertested, please let me know..

I read a post about Upgrading an HP 500 (carb)

1. Replace rect heads for large oval port 20 hp
2. Replace Single plane intake with Performer RPM Air Gap
10-20

Operating a WOT @5000 is Not High enough to effectively flow Large Heads and Hi rise single plane manifolds.

Did you also re-use the stock cast crank, 3/8" rods, and cast pistons while upgrading the HP to 425hp from the Merc 330 ??? Or did you swap to all forged internals? Do you happen to remember what RPM it made 425hp at?

About 5 years ago my cousin rebuilt his Merc 330's. He went to 461cid, retained the same stock cast cranks, 3/8" rods, and installed new cast pistons and 2-bolt main blocks. The only thing he did to upgrade the stock rods was had them shot peened, and replaced the stock rod bolts with ARP rod bolts and reconditioned, had the rotating assemblies completely balanced and the blocks align honed.

He used some old JUNK GM large oval port semi open chamber heads that he had JimV install 2.19" intake valves and 1.85" extaust valves and did some bowl/pocket port short side radius work on the heads. Funny, the 1.88" exhaust valves did not work/flow as well in that particular head because of the way the chamber was designed....the 1.88" valves actually were too large and did not flow as near as well as the smaller 1.85" exhaust valves...at least in this reference.

He used a hydraulic flat tappet cam of 218*/226* (at .050" lift) .515"/.515" lift on 110* lobes, dual plane intake manifold, Holley 830cfm carb, and had the cylinders in the blocks all "bore notched" to unshroud the valves for better flow, 8.6 comp ratio, 32* of timing, and they made 461hp @5100rpm and 510 lbs of torque at 3600rpm on Tom Earhart's dyno with car dyno tubular headers.

Torque stayed very flat up to 5000rpm. He could have used a cam with more duration, but we wanted to keep the RPM's at about 5000-5200rpm because of the cast pistons just to be safe.

The engines were installed in a 1988 32' Baja and I think it would be fair to assume that the engines have lost about 25HP going from the dyno headers to a dry piped GIL exhaust manifold in the boat. He has only tried one set of props (went from a 21" 3-blade to a 25" 3-blade) and said he picked up 10mph in the midrange and on top.

I believe that a lot of people get all wrapped up about 4 bolt mains, and 7/16 rods and such. 425 HP is nothing for a 454 today. If you were to use ARP fasteners, Edlebrock intake, good carb and cam, some clean up of the heads, and a seasoned engine builder that has good attention to detail, you will have no problem reaching your goal.


Darrell.

That sounds like a hell of a cam. Which one did you use?

Fastenough, Those peanut heads have a ton of material in them. You can either buy the Merlin large oval ports( around $750 each fully assembled in JEGS catalog) or you can take those peanuts to a good engine builder and have him cut a ton of material out of the intake ports.

You can make pretty good power with those stock heads.

A freind of mine who has been building BBC for a long time put those peanut heads on a flow bench in stock configuration and found that they will flow all the way to about a .550 lift cam.

I have a couple sets of the merlin ovals myself and they work really well.

Thanks everyone for you help. I talked to a Performance shop here in OH that does race cars and some boats and they told me about the same recomendations as all of you. They said some head work, intake, and cam and 430hp very easy to achieve. They said they would check they bottom end and if it needed redone total would be around 3k. That seems like a good enough deal. I think I might go this route in a few months. Thanks again for all the good advice.
Brent:D

Still wondering about that cam ghitner used?

One more question for everyone
 

Do I really need the cooler for the oil and pwr steering?? Not sure how well the old system is working anyway. I use syn oil, just wonder if the oil will really get that hot under normal running condidtions.:readinghelp:

Yes. Oil coolers are a must.



Darrell.

Yes, you need the oil cooler with the extra power. I know this sounds screwy but I have that also. The company sent me two of the one I'm using because I thought I was going to a dual engine in the future. it is a P/s and Oill cooler like stock. I also have the custom pushrods for this setup that you will need for the Merlin heads. As far as the peanut ports? My opinon is throw them away. They will never make power in the range you are looking for. NEVER. Start with the GOOD basics. This combo took my boat from 46 MPH to 63 MPH Fact on GPS.

Lunati 612/ 612 lift, 112 Deg lobe center w/ no reversion issues...duration I can find for you, great cam with excellent dock etiquette. I would run this again for a non blown application. Do you need a part #????

Wow, that is a big cam. Is it roller or flat tappet?

Yeah, I'd like to have a part number.

Thanks.

WHat custom pushrods? You need custom bolts, but I have been using regular stock length pushrods and havn't had any issues.

Help me out here. My rollers are hitting the middle of the valve like they are supposed to also.

Just checking because I have not heard of this with the thickeer heads like merlins and darts etc.

Roller worked awesome. 50274 LUN

I allways measure pushrod length on any build and I had these made @ Herberts to optimize the valvetrain geometry.. If you want the lengths I can get then 4u...

ghittner, I had a question for you back on Post #11 (first paragraph) I was kind of curious about---don't know if you may have missed it. Thanks

I am curious too. What do you want for those dust collecting parts? I have a 454 mag 1989, stock.

That is a pretty big cam. I am going to try it on one of my 582's and see if it wakes them up.

Hey KAAMA, you can get away with using a lot of those stock parts out of the 330. We actually have a boat with a 10-71 blower and 100 NOS shot running 2 old short blocks off of a 330 merc. We did change the pistons, pins and bearing, but are still using stock crank and rods. We rarely break a rod or have a crank issue. We do break a lot of valves and cams that are supposed to be high end aftermarket. These engines have been to 7000. We started putting 6k limited from MSD on them. Not sure how much longer they will run, but they have 2 good seasons on them. Shouldn't be any problem fo you at all to make a 500hp motor with them.

My .02 contribution to the discusion.

Cast Crank, stock 4 bolt block, l think the pistons were stock or a stock type but 10:1.

Give me a call to discuss if you are interested. 949-701-0900. Greg

Thanks for your input. Okay, I just want to make sure I have this straight. You have conintued using a stock Merc 330hp shortblock i.e. cast crank, GM 3/8" rods, but you have swapped out the the stock cast pistons for some forged pistons while using a supercharger and NOS on top turning them to 7000rpm???? I would have to say that is a pretty interesting and guttsey test platform!

What Make/Length boat did you put these engines in? What Brand/Part No. of valves and cams are you breaking???

Are the cams a flat tappet or roller set-up...solid/mech or hydraulic???

Please keep us posted on this. I'd like to know anymore problems you have with these super duper mutant 330's you have on steroids. :D You kind of remind me of "Articfriends" aka Smitty----he's another good test platform guy who trys a ton of stuff to see how it works and then passes on the results to our bennefit. :)

Thanks for responding. So, besides the stock CAST crank, you're using the same stock GM 3/8" rods.......and you are still using "CAST" pistons only in 10:1 comp ratio to make 425hp....correct? What RPM were/are you turning?

to the top

These threads frustrate me. I wish some one would just post the recipie for different engines. I mean its jsut a matter of putting parts together to get the results we all want. There are tons of options out there but that doesnt mean we have to use all of those options.

I know someone is willing to share different engine building recipies. Meaning block crank pistons, heads, cam intake, carb etc...

Do it for 454 block 502 and 540's. It cant be that hard its just not my area of expertice or I would do it for everyone. A thread like " how to build a stong marine engine."

From what I have learned on 454 we would want forged crank and pistons, rect port heads, roller cam(specs?) roller rockers, edelbrock dual plane intake, carb? oh and dont forget high perf exhaust.

I am not trying to get 9000 hp out of a block but 450 would be good.

Someone who I respect once gave me this to work with. I can 64 now and would like to hit 70.

1. Edelbrock Air gap intake #EDL-7561
2. Holley 800 Carb #HLY-0-9022
3. Holley electric fuel pump #HLY-12-801-1
4. Crane cam #134561
5. Crane hydraulic lifters #99277-16
6. Crane push rods #13634-16
7. Crane timing chain #13975-1
8. Comp cams roller tip rockers #CCA-1411-16
9. MSD distributor #msd-8560
10. MSD brain box #MSD-6460

This should put you into the low 70's if you get a 23 Mirage plus prop. The 21 is too small. If this doesnt make you go as fast as you want to go...I have a motor in the corner that will.

4 bolt block, forged merc crank is fine, GM Dimple rods (7/16), Forged piston, (any SRP, diamond, etc will work) Clevite H Bearings, build comp ratio to your comfort level. I suggest 9.5:1+- 87, but recomend 93 always.

For the top it is more complicated, as this is where the budgets come into play.

Super cheap: GM square port heads, Flat tappet hydralic cam, Mid range roller rocker, Good comp, crane spring out of the catalog, have your machine shop order from the supply house. Use a good quality stainless valve. The old 420 merc dual plane manifold is great if you can find one that is not rotten, Edelbrock 454-R is a good single plane choice. 850 holley double pumper and a 130 mech fuel pump and you are on your way.

Cam specs will depend on your exhaust.

You can build that engine for less than 5K if you shop the parts right and don't get into a hurry.

With a CMI type header, your cam can be more aggresive and you can see 500+- HP out of it.

That is the most sane way of building a 454, since it realy doesn't make a lot of sense to over build one.

I have gotten a little crazier and used a solid lifter flat tappet nad made more power.

Putting the high doller roller cams and springs and spending all that money won't NET you a big enough return on your investment IMO.

If you can afford the fuel, up the comp. a little and you will see a better gain.

With the prices of blocks, cranks, rodes etc coming way down and the general knowledge becoming more readily available, If you are going spend a lot of money, you might as well go to 540CI+ so you can see a bigger net return.

I have one of these almost ready to go sitting here. THere are some variations. My 27' Magnum ran in the low 70's with this engine on oval port heads, Now it has square ports and a much better carb.

PM or call if interested. Jeff 832.439.5304

Send me all of your old bolt ons and I will clean them up and get them painted and run on the test stand and send it to ya.

Price is right. I have engines stacked up in this shop.

My stuff is coming off a mkIV block that a cylinder craked. SO I have an edelbrock performer intake, Quadrajet carb, thunderbolt ignition, what other stuff can I rob and put onto a new longblock? My heads are oval port so I am not sure I should use them.

If htye are 330 heads, then they are peanuts. Throw them away.

Dump the quadrajunk carb also.

Ignition and intake are good though. Use the block and oil pan, rebuild the oil pump, but a new one is less than $100. See what rods are in it? Might be 7/16".

Send me your block and Ill build you a good one, or I'll send you one of the ones that I all ready have here.

Its at a machine shop now. They told me its a 2 bolt main with cast pistons and crank that is now seized and the block that is crakced is a sleeved cylinder so I am not real keen on reusing it. They daid I have oval port heads not peanut port.
I found a long block here in mi that has a roller cam dualplane intake iconell valves rect prot heads rebuilt 30 over has forged crank and pistons(cant remember who made those but I have heard of them before) 4 bolt main.
I have heard that about the quadrajunk but it has not failed me, why is it junk? I have heard the holley carbs can be finiky.

Wouldnt you need the water pump etc...

No water pump if you convert to a crossover type. 1 less thing to worry about. Quardrajunk because they don't flow worth a chit and no HP. Decent on a car, but nt enough to work with on a boat.

If you have a deal over there use it. The big ovel chevy's are great up to a certain level, but they are especially great in the mid range. Just depends on how much cam you are putting into it. Go with the 750-800 style holley and be done with it. I have a shelf full of stuff I can sell you if you want to do something with the engine you have.

I can send you a ready to bolt on 750 for $300 shipped. it has been freshened. You will have to play with the jets a little after you bolt it on. If you trust where that long block is coming from and the price is right, I say jump on it. Make sure you know your comp ratio and your cam specs though on the way in as those are the only 2 issues I see. Otherwise, that engine will be a night and day difference from what you are pulling out.