SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: hallettman on January 27, 2010, 04:37:04 PM

Title: adding power to a 454
Post by: hallettman on January 27, 2010, 04:37:04 PM
 i have a stock 454 bbc. I want to give it some more horse power. what is the best way to do this? I have a weiand intake stock heads and cam ad a holley 715 cfm 4 barrel carb.  Iwas thinking about changing the cam but im not sure how much of a difference this will make.  I dont really have the budget to bore it out. I guess my main question is will a cam change make a noticable difference or am i just wasting my money?
Title: Re: adding power to a 454
Post by: Luckie Stiff on January 27, 2010, 04:54:28 PM
A cam, an 850 mechanical carb, good single plane intake and ignition system will be your best friends. All relatively affordable mods.
Title: Re: adding power to a 454
Post by: 88CARRERA on January 27, 2010, 05:45:29 PM
ah, you dont want that thing, just give it to me so i can finish my eliminator project, and i will put a video up on youtube so everyone can see it. then you can watch it and show your friends that you donated to a good cause! a broke scjb'r!  haha, what stiff said! good luck!
Title: Re: adding power to a 454
Post by: GlassCutter on January 27, 2010, 06:17:09 PM
If you R&R the cam do a ton of research on your purchase and your mechanic.    Cams are one of those things that it is critical to get right for peak performance and really easy to end up ruining a motor by improper break in or banging a valve on a piston because you were not precise on your measurements.
I'm just sayin' . . .


I know a real good mechanic that drives thru ST. George every month or so.  Lives in Roosevelt but comes to So Cal often.
Title: Re: adding power to a 454
Post by: hallettman on January 27, 2010, 06:35:28 PM
There is a machine shop down the street that rebuilt my father in laws 454. I will probably hit them up. =They did a good job on his engine.  Thanks for the advice!!!
Title: Re: adding power to a 454
Post by: GlassCutter on January 27, 2010, 07:20:27 PM
Make sure they understand that boats and cars require different tolerances.   If all you are doing is a cam you should be OK.   If they are going to do the break in even better.   Good luck.
Title: Re: adding power to a 454
Post by: IRRebel on January 27, 2010, 10:55:25 PM
I say Huff it!  >:D

No, really, Skips got you on the right track. You can literally toss a 20% or better HP increase just by the right cam/lifter/spring package with a good single plane, or really a good dual plane intake. Provided the bottom end is in good shape.

A lot depends on current compression ratio, load, IE, impeller and pump condition, etc.

Anything above a, say "260" cam, is probably going to respond better in a boat with a single plane. Barry, Dave or Paul will correct me here if I'm wrong, but I would be looking at something like a Comp Cams 292 Marine package and a Weiand Stealth or Victor intake. Going to require some work degreeing it in and making sure valve/piston clearances are ok, but a pretty potent package on ANY brand engine and some pretty damn good bang for the buck. But again, the 292 likes compression!  If lower, might want to step back to the smaller cams.

Dunno if this helps or not.

Ray
Title: Re: adding power to a 454
Post by: hallettman on January 28, 2010, 04:49:16 PM
My father-in-laws 454 went into his eliminator, and he ran it all last summer without any trouble. I know he put in a 300/300 cam and it brought his HP up to about 450,  so it seems that this shop knows what there doing. Thanks for all the advice I really appreciate it.
Title: Re: adding power to a 454
Post by: Nordie on January 28, 2010, 07:49:08 PM
i tried to post on this topid earlier but i guess my cell phone hate me! anyway if that is a mercruiser block and it is in good shape by all means try to keep it! the marine blocks are a good tool....they are known to have a more nickle/tin content, and work alot better in marine applications!
Title: Re: adding power to a 454
Post by: hallettman on February 04, 2010, 09:07:49 PM
drop the engine off at the machine shop.  He is giong to tear ita apart and see how it looks. He said from what he can tell its probably a 8 to 1 comp. engine.. He suggesated going from the flat piston to a dome piston to raise the compresion. He said the intake i have is a good  middle range dual plane and i probably wont notice much of a difference by switching to a single plane.  So right now it looks like new pistons and a cam/ lifters. I will keep you updated.
Title: Re: adding power to a 454
Post by: 76 Bonneville on February 04, 2010, 09:44:05 PM
When we built the motor in our cruiser, back in the mid 90's. We went with the performer RPM intake, performer RPM cam(565 lift), 750 carb, forged flat tops, Crane rockers and old school 97cc closed chambered heads to bump the comp. If it has the peanut port heads, you gotta replace those.
Title: Re: adding power to a 454
Post by: TJS Nordic on February 05, 2010, 05:33:45 AM
Put an blower on it. See my build up in my sig... ;D
Title: Re: adding power to a 454
Post by: maddogg20 on February 07, 2010, 10:54:01 PM
I had a stock 454 when I got the donor hull that i bought. I put some 1.7 ratio roller rockers on it, got some oval port heads, a clay smith cam,  one piece pushrods, an edelbrock victor 454 manifold, 750 4 barrel carb, 10 quart oil pan, high flow oil pump, and a few other goodies and shes happy :-)

http://www.socaljetboats.com/projects/new-to-forum-new-project/

thats my project build thread.
Title: Re: adding power to a 454
Post by: hallettman on February 11, 2010, 04:47:55 PM
stop by the machine shop today. Block is completely disassembeled. machinist said i probably had about 300 HP. will be around 425 to 450 when he is done. cant wait for summer.
Title: Re: adding power to a 454
Post by: lilrick on February 11, 2010, 08:15:18 PM
To answer the original question about noticing the difference in a cam change, my answer would be no. There are three basic elements to making horsepower: compression,caming, and runner volume. If you match and balance all three of these things- you will have a noticable increase in power.
Title: Re: adding power to a 454
Post by: GT Jets on February 11, 2010, 08:23:55 PM
To answer the original question about noticing the difference in a cam change, my answer would be no. There are three basic elements to making horsepower: compression,caming, and runner volume. If you match and balance all three of these things- you will have a noticable increase in power.

I will respectfully disagree... :thumbdown:       ;)

Sometimes a cam change will make a world of difference, especially if it is under cammed to start with...Just my personal opinion.

The right camshaft can increase the dynamic compression by leaps and bounds, we found this out running our marathon motor on a dyno with three different setups, the largest carburetor did not necessarily make the most HP, but really effected the max torque and the camshaft change really made things interesting...

What was more interesting to me (didn't really surprise our machinist) was cam timing, 3* was worth 15 HP not to mention about 70 RPM, had I not seen it for myself, I would be a non believer... :screwy:
Title: Re: adding power to a 454
Post by: lilrick on February 11, 2010, 09:40:11 PM
I will respectfully disagree... :thumbdown:       ;)

Sometimes a cam change will make a world of difference, especially if it is under cammed to start with...Just my personal opinion.

The right camshaft can increase the dynamic compression by leaps and bounds, we found this out running our marathon motor on a dyno with three different setups, the largest carburetor did not necessarily make the most HP, but really effected the max torque and the camshaft change really made things interesting...

What was more interesting to me (didn't really surprise our machinist) was cam timing, 3* was worth 15 HP not to mention about 70 RPM, had I not seen it for myself, I would be a non believer... :screwy:
Makes sense. But, this guy has or had a bone stock 454. They are typically 8:1 motors. I think it would be silly to throw a new cam in a stock motor to go faster. I think Hallettman is doing the right thing by upgrading the ENTIRE package. It is money well spent. lilrick
Title: Re: adding power to a 454
Post by: GT Jets on February 11, 2010, 10:46:26 PM
Makes sense. But, this guy has or had a bone stock 454. They are typically 8:1 motors. I think it would be silly to throw a new cam in a stock motor to go faster. I think Hallettman is doing the right thing by upgrading the ENTIRE package. It is money well spent. lilrick

Couldn't agree more about going all the way, you just have to understand the way my brain works.... :screwy:

Total build, machine work, bearings, rings, cam, lifters, pistons, gaskets, freeze plugs, and so on....$2000-$3500 (depends on quality and upgrades and how much you DIY).    HP when done, 400-450 (open for +/-)

This is if you don't have to replace any major components (Dave is flipping out right now  ;D)

Cam kit with necessary gaskets...$500.. :thumbup:   HP when done, probably 375 (same+/-)

So for $1500-$3000, you get an additional 25-75 HP  :sly:

See what I mean?

He still totally went the right way IMHO, but I am a broke ass boater who just wants an opportunity to break some stuff...:thumbup:

And who says 8:1 is a bad thing?, that says small turbo, or water injection (prefer methanol) all day long...again, I'm cheap.

GT
Title: Re: adding power to a 454
Post by: IRRebel on February 11, 2010, 11:34:20 PM
I'm with you Glenn on this. He went the right way, and lord knows going to probably more than happy with the results and durability of the thing.

But my thinking is not unlike yours, growing up building hot rods, out of anything from Nova's and Chevelles to even a Ford Granada!(Nowadays they have their own class, "Rat Rods" Little did we know back then we were offending the guys with money!)

But I recall thinking every time, what's an easy, INEXPENSIVE, way to make some good HP? Doesn't have to be easy, necessarily, but cheap, OH YEAH! These are my HS days and still sticks with me, even though, as I grow older, where durability and quality are paramount, I'm still looking for that shortcut. Just inbred in our generation, nothing more, and I look out for that in myself these days. (Miss catching it most of the time).

As machining costs have gone DOWN over the last 30 years, comparatively, taking inflation into account,  for most of us old schoolers, "machine shop" was the LAST thing we wanted to hear. Engine Doctor, Lakesonly and Obnoxious1 can probably concurr, that was BIG BUCKS in those days! We wanted to NOT pull a good running engine, but toss in a hotter cam, intake, carb and ignition and GO. Good 4 Bolt Chebbies, 340 Mopars, 421 and 428 Pontiacs and the good 'ol 390 and 428 Fords (noone had really "discovered" the 429/460 as a hot street engine yet, it was a "smogger" engine to us then) were a dime a dozen back then. Porting and polishing??? Forget it! That was for the mega rich!

Throwing myself back into all this on these boats has made me happier than a fat woman, alone, on Tim McGraw's tour bus. But New School is a LOT different, and better! Found this out on Moo's engine build, big time. But still, trying to adjust dollar value into it, it cost me probably half what it woulda cost me back in my HS days. The current Blower motor, well noone I know of would have even given second thought to it, that was Hot Rod Magazine stuff. Now I've got one (I'm not allowed to put in what it was inended for) and a couple more to build, and they're everywhere.

Just some food for thought. Sorry for the thread jack and rant, but thought it might be relevant. Prolly not, but I certainly feel better!

Ray
Title: Re: adding power to a 454
Post by: hallettman on February 12, 2010, 07:23:10 PM
origianlly i wanted to gain as much power as possible for the cheapest price.  I figured a cam cahnge would do the trick. after talking to the machinist he said there is no more power to gain from a 8 to 1 comp engine. if you want to increase power you have to raise the compression. the only way to do that is through the heads or pistons and changing pistons is the cheaper way to go.. I didnt want to spend that much but if i have the engine out and apart im going to do it right and not have to worry about it again. He said he is going to bore it out replace and balance pistons, new cam and lifters and rebuild the heads for about $2000. will add about 125 to 150 HP. He also said the water passages in the lower half of my engine were completely blocked with hard sand. he has to clean it out with a coat hanger. He said if i hadnt pulled the motor out to be rebuilt i would have had problems this year with the engine overheating
Title: Re: adding power to a 454
Post by: lilrick on February 12, 2010, 09:19:17 PM
origianlly i wanted to gain as much power as possible for the cheapest price.  I figured a cam cahnge would do the trick. after talking to the machinist he said there is no more power to gain from a 8 to 1 comp engine. if you want to increase power you have to raise the compression. the only way to do that is through the heads or pistons and changing pistons is the cheaper way to go.. I didnt want to spend that much but if i have the engine out and apart im going to do it right and not have to worry about it again. He said he is going to bore it out replace and balance pistons, new cam and lifters and rebuild the heads for about $2000. will add about 125 to 150 HP. He also said the water passages in the lower half of my engine were completely blocked with hard sand. he has to clean it out with a coat hanger. He said if i hadnt pulled the motor out to be rebuilt i would have had problems this year with the engine overheating
Hmmmmmm....I think I've heard this somewhere before. I completely agree with your machinest. Sounds like he put you on the right path. Again, not much to gain from the 8:1 motors from just a cam change. What cylinder heads are on the core engine?? Getting back to the basics, Since You are going to bump your compression and are going to purchase a new cam, Now make sure your cylinder heads are worth rebuilding. The optimal cylinder head made by GM for YOUR SPECIFIC applicationwill be the 049 or 781 casting. Throw the big stainless valves in and you will have a very nice engine that will last many years!!!!
Title: Re: adding power to a 454
Post by: Luckie Stiff on February 13, 2010, 07:52:33 AM
Listen to lilrick on this, he's pointing you in the right direction
Title: Re: adding power to a 454
Post by: lilrick on February 13, 2010, 02:54:39 PM
these are pretty reasonable

(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi182.photobucket.com%2Falbums%2Fx151%2Fcnationalteach%2FIMG_1070.jpg&hash=3d520932bcbe02a7f6fce78b2fcd8c135b4f6a3f)
Title: Re: adding power to a 454
Post by: hallettman on February 13, 2010, 09:21:05 PM
not sure what the casting was on them but i know the machinist said they looked good and should work fine with the engine. He hadnt had a chance to tear then apart yet buy he is planning on rebuilding them.
Title: Re: adding power to a 454
Post by: GT Jets on February 13, 2010, 10:19:51 PM
not sure what the casting was on them but i know the machinist said they looked good and should work fine with the engine. He hadnt had a chance to tear then apart yet buy he is planning on rebuilding them.


OK, hold the phone.....

How were pistons ordered if the cylinder head specs aren't known?

The cylinder head to piston relationship is what determines the final compression ratio, nothing else except deck height and gasket thickness can alter this number.

In your original post you stated that you did not have the coin to do a rebuild...Yet here we are.

For the record, if the heads are some 120+cc chambered heads and the engine had flat tops (I'll assume cast) then I would agree on the 8.0-8.3:1 ratio, that being said, if you "bolted on" a set of 90 cc heads with the right gaskets, your looking at a 9.0-9.5:1 deal, throw in the correct bumpstick and a good tune, you're off and running, with an estimated 375 to 400 HP, this all is assuming you had a descent condition bottom end...

I was all excited when I read the opening post that we were talking budget build, most of you had great input, with the exception of TJS Nordic (that guy has issues   :screwy:    ;D )...

I guess my point is, I am glad you have the opportunity to do it from the bottom up, but that was not the original intent from what I gathered and wanted to say that I think it is OK to go half way if that is what you have the means to do.  :thumbup:

If you get the head numbers I would be interested to know, if you feel like it that is....

This is not a blast at anyone, it just seemed that you were being discouraged to build a low compression BBC and I have spent a lot of time and money lowering the compression of the last three BBC's I have (of course one of them was at 13.5:1  :screwy: ).

FWIW, the 9.5:1 runs the hardest and I run a blend of 50% Rocket 106 and 92 pump gas, the timing likes to be at 37*BTDC, it goes to 5200 RPM and hits a virtual wall..... :sly:

From one broke ass boater to another, I hope she exceeds all expectations  :thumbup: 8)

GT

Title: Re: adding power to a 454
Post by: hallettman on February 14, 2010, 01:25:59 PM
no parts have been ordered yet. the engine is still being torn apart and cleaned up. originally i wanted to do this as cheap as possible and gain as much power as possible.  After talking to everyone on here and the machinist i decided that cheapest isnt always best. i woulkd rather spend the money now when the engine is apart than have to do it again later. i didnt really ahve the budget to do it all right now but i worked ouat a deal with the machinist. I told him i dont need the engine foar a few months and that there is no hurry.  this will give me time to save some money and he can work on high priority jobs in the meantime. all in all i think rebuilding the whole engine is the better way to go.
Title: Re: adding power to a 454
Post by: GT Jets on February 14, 2010, 01:32:26 PM
no parts have been ordered yet. the engine is still being torn apart and cleaned up. originally i wanted to do this as cheap as possible and gain as much power as possible.  After talking to everyone on here and the machinist i decided that cheapest isnt always best. i woulkd rather spend the money now when the engine is apart than have to do it again later. i didnt really ahve the budget to do it all right now but i worked ouat a deal with the machinist. I told him i dont need the engine foar a few months and that there is no hurry.  this will give me time to save some money and he can work on high priority jobs in the meantime. all in all i think rebuilding the whole engine is the better way to go.

Sounds like a smart way to go, sort of a lay a way for engines... :thumbup:

The cylinder head choice should be at the top of the wish list as far as performance capabilities, the wrong heads for the application can make or break a package...They also need to be matched to the rest of the components as far as optimum torque/hp rpm numbers....

Start shopping for boat specific parts now, there are some unbelievable deals out there right now...

GT
Title: Re: adding power to a 454
Post by: IRRebel on February 14, 2010, 05:19:54 PM
Start shopping for boat specific parts now, there are some unbelievable deals out there right now...

GT

You ain't kidding.

http://phoenix.craigslist.org/cph/pts/1587786625.html

Ray
Title: Re: adding power to a 454
Post by: GlassCutter on February 14, 2010, 05:43:32 PM
Ray step away from the computer.      Put down the credit card.    You really need to let this one go  LOL
Title: Re: adding power to a 454
Post by: IRRebel on February 14, 2010, 05:47:31 PM
Awwww, c'mon, just what he needs!!!! >:D

Ray
Title: Re: adding power to a 454
Post by: beerjet on February 14, 2010, 07:15:46 PM
Ray step away from the computer.      Put down the credit card.    You really need to let this one go  LOL
Parastic drag , what every motor needs 
 :thumbdown:

-beerjet-
Title: Re: adding power to a 454
Post by: GlassCutter on February 14, 2010, 09:34:17 PM
I just noticed that since Beerjet has started to hang out with the band he has started to look a lot like Ron Jeremy.   Maybe its just me but I dunno . . .
Title: Re: adding power to a 454
Post by: beerjet on February 15, 2010, 09:02:51 AM
I just noticed that since Beerjet has started to hang out with the band he has started to look a lot like Ron Jeremy.   Maybe its just me but I dunno . . .
Thats cuz woman love hairy chests and mustaches .
Right John  ;)
Oh, and Lilrick knows his way around a Cheverolet.

-beerjet-
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