A buffalo’s first bowtie

The hill I have to climb is getting less and less steep! Thanks again for the ongoing tips. The crank was not as smooth as you described before I unbolted it, but it wasn't bad either. I put up a pic of the lifters since they were mentioned...though I'm sold on the roller system...and none of the grooves in the crank are enough to grab a fingernail. I'm guessing a polish will be enough.

eric lavine wrote: i do not know if you can use a standard left hand cam, im on the fence but i would think they designed that gear set to accomadate the normal rotation cam just for that reason.

That would make sense. The cam definitely spins in the same direction as in a standard rotation motor. It still seems like the firing order would be different, but Im not familiar with the set up.

If you cant use a standard automotive cam, Im pretty sure you can forget about the roller conversion. If theyre like the Fords, having a reverse rotation roller blank made will cost big bucks ($700+). Nothing wrong with a flat tappet though- just use the right oil (both during and after break in) and you'll be fine.

TRBenj wrote: If you cant use a standard automotive cam, Im pretty sure you can forget about the roller conversion. If theyre like the Fords, having a reverse rotation roller blank made will cost big bucks ($700+)

The conversion makes sense to me for several reasons, so I'll probably do it for a few hundred extra. I mean to keep this boat for a long time!

Summit has some retro-fit cam and lifter kits that are similar to the crane 139001 that I liked the description of earlier in this post. I don't know if they'll work and maybe we'll hear more here when everyone's home from the holiday, but I'm going to split a half day tomorrow between the machine shop and phone.
Wish me luck!    

Crane cams recommended the 139001. $1200-$1300 for the cam and lifters(roller) and another $200-$300 for rockers. The prices on Summit looked better, but I don't know if I'm comparing apples to apples.
The guy I talked to didn't want to say that any cam made for this motor would work but said this one would. He also said the motor would be more efficient if I raised the compression to 9.25-9.5:1

TRBenj wrote: Wow, thats some serious money for a cam!

My thoughts exactly when the summit kits are in the mid $700's. He did give me a bunch of reasons why the roller is so much better for the big blocks, but he has a part to sell as well!

I also found out that a friend of a friend is the service mgr at the local marina so I'll get some input from him...and I found the machine shop that does the marina's work and will take mine there.

2 points for 79! LOL

87BFN owner wrote: Buffalo Me and the boat doc have already had this conversation about the 454 a regular cam can be used. That info came from woody at SECC. So I believe nutty to be wrong on that one. If you find a roller cam conversion kit let me know. I am looking for one as well. Nutty If you can think of a reason on why woody is wrong about the cam let me know.

Okay, here's my thinking on this. The standard rotation firing order of a Chevy 454 is 1-8-4-3-6-5-7-2. The firing order of his RH engine is 1-2-7-5-6-3-4-8 (as he has already verified). The gear setup is of course going to rotate the cam opposite of the crank (which will be in the same direction as a standard cam). No one is arguing this against this point. The problem is that after the #1 cylinder fires, the crankshaft is going to rotate backwards and set up the #2 cylinder to fire (remember this is the firing order of this engine as indicated on his tag). But the cam (being standard and rotating in the standard rotation) has the #8 cylinder set up to fire. In other words the crankshaft and the cam will be grossly out of phase with each other. The valves will be opening and closing at the wrong times. At best you'll have an engine that won't run. At worst may bend some valves by hitting them with the pistons.

I think people are forgetting that you have to take into account the way the rod journals are positioned on the crankshaft. The firing order is somewhat limited by this aspect. The exception is that opposing cylinders can be swapped. Opposing cylinders (for those who don't know) are cylinders that are in the same position and moving in the same direction, only they are on opposite strokes. Two opposing cylinders on this engine are: 1 and 6. When cylinder 1 is at TDC compression cylinder 6 is at TDC exhaust. These 2 cylinders can be swapped in firing order, but it's not just by changing plug wires. The cam has to be ground with this firing order. An example of this very thing is the SBF camshafts. The 289 and older 302s use a different firing order that the newer 302s and 351s. However, only opposing cylinders were swapped to make this happen.

I've done my best to convince you guys why the standard cam won't work for his engine. If you are still in doubt of what I'm saying, that's okay. But prove it to yourself first. Take your used cam to a engine builder. Ask to see a used cam from a standard rotating engine (454 of course). Line the cams up together and rotate them so that #1 cyl lobes point in the same direction. Now compare the rest of the lobes. I'll bet any amount of money they are different. Also, call one of the major cam companies and check with them. Call Crane or Comp Cams. I'm sure they have dealt with this before. Don't just take someone's word on it! I'd hate to see you ruin your newly built engine by installing the wrong cam.

Brian

Nutty
I planned on doing my homework before I build my 454. I was mearly piping in my two cents worth based on conversations with the boat doc, who inturn had conversations about this motor with woody at SECC. I remember stating in my post if you had a specific reason on why you thought a normal cam would not work that I was all ears.

Buffalo
What came did crane recommend you use then. Could they supply you with one or would it be a special order cam at a pretty penny.

Tr, i was refering to some high hp increases such as 12 to 1's, aluminum heads and so on and with what i think Greg was more looking for is a reliable turn key engine, hes attacking at it from a reliabilty stand point, sure bump up the compression ratio to a useable ratio such as 9.5 or even close to 10:1 anything after that your beating a dead horse. you get up over 450 on these big blocks and your always tweeking something
If i had 2 grand to spend on this motor i would first go after the cam, after the machine work is done, it would be a roller close to the stock lift and duration, i would spend money on the stock heads, if pistons were needed i would go to 9.5' or in the general area, then intake and carb. BBC's are diamonds in the rough they have the power hidden and you have to find it. this boat stock with the BBC will rip your arms off as it is so power isnt an issue, thats why i was leaning more towards reliability, you can run a hotter motor but along with it comes the problem and lets face it this boat aint easy on the gas and the hotter you build it the more fuel your gonna use, Jacking up the HP on this boat has no advantadgs IMO, but i think the fuel economy and reliabilty does

eric lavine wrote: this boat stock with the BBC will rip your arms off as it is so power isnt an issue, thats why i was leaning more towards reliability, you can run a hotter motor but along with it comes the problem and lets face it this boat aint easy on the gas and the hotter you build it the more fuel your gonna use, Jacking up the HP on this boat has no advantadgs IMO, but i think the fuel economy and reliabilty does

I still disagree, as I havent been overly impressed with the stock 330hp 454 in Nautiques. Bumping compression to 9.5 or 10:1, and improving airflow through the motor (heads, intake, cam) should improve efficiency AND power. Of course, you have to use the right parts and assemble them properly- that goes without saying- but there should be absolutely no tradeoff in reliability.

If it were me, a full rebuild would be a perfect time to go with a mild stroker. Id invest in a quality set of iron heads that boosted compression to ~9.5:1, and get an intake and FT cam to match. Id use high quality gaskets, seals and bearings. That would make for a rock solid 400-450 hp motor that would last another 2500 hrs. Different strokes for different folks

87BFN owner wrote: How could he recommend a cam with out talking about firing order? If he said a normal cam will not work. Does that mean they carry a cam for our application, or would they have to make it.

First note that he wasn't in a good mood and probably not in the mood to deal with an amateur. I explained the gear drive and RR crank and that's the part # he gave me. It's an off-the-shelf item they have for LH motors. When I told Comp that it was RR, he said hold on a minute! I'm waiting for a call back from him(comp)...he's looking to see if they have a core. I'm also waiting for LSM to call back. I think it was Nautiquematt who recommended them and I think Tull went by there. LSM's home page says they do counter rotation cams, etc.

Eric, that's exactly my plan. Gas will only get higher, so my goal is to efficiently burn the gas I'm putting in it anyway. I'm completely enjoying doing this work, but I don't want to do it all the time(not the same motor)! Turn key like you said.
I don't know yet what it'll cost to port and polish these heads, but I am going to have it balanced for $250.

TRBenj wrote: Different strokes for different folks

The cylinders are badly scored...it'll at least get a little bigger!

reading the service manual it states both firing orders, with the HO version it used the automotive order. I think if you realy look at the crank relative to the firing orders there might not be an issue.

eric lavine wrote: Edit, basically you need that cam, it is a special cam thru pcm, its not available in a roller it retails for $280.00 or there is other options such as the one you were looking into, but a lefty wont work

Would it be an option to switch from a gear drive to a chain, and use a RH cam?

Anyone know where the part # is supposed to be on the old cam? And yea I know, look at it; but I don't see it. Most all of the other parts say GM and a #, but I don't see that here. On the back end it has hand tooled #'s that say 8899. There is a casting mark behind the 3rd lobe, 349...and I don't have the puller for the gear, so I hope it isn't under there?!!? LOL