454 Carburetor question?

[vinny p.]

You need to post all the specs on that cam. 590/610 doesnt tell much of the story. I can say, that lift is very high for your engine. I'll give you a for instance, I am running a pretty well worked 540. My lift is only 598/608. I need to see the rest of the #'s.

 

[happy]

not seeing a whole lot of figures adding up here.. gonna have to have some mo info.. if your going to spin 5600.. gonna need a lot more info.. right now the #s aint giving.. send some pics of that exhaust gils ususaly rot right under the riser.. the pipes are fine, normally, but bent for the cigarette.. not your boat.. so that may not be a good deal

get a list from your machine shop, and post it.. so we can see whats really going inside your engine..

 

[Big Red]

He needs to do more than a valve job on those heads if he's going to run a 610 lift cam. The stocks springs are useless and if they try to shim them to build the spring presure up he's going to get spring bind. When that happens at WOT you will be looking for the closest trash can to throw everything in.

Call Crane with the cam grind number get the recommended springs, retainers, and locks. Give them your new rocker ratio and get the right length pushrods. Once the valves and seats are ground thats going to change spring pressure and all that has to be miked out again and proper shims used. If your valves are tired I would also change them do to all that added spring pressure. It would be bad if you dropped a valve and wiped your bottom end out.

Investigate your heads good before fixing them. If you need all new Valves, seats, guides, springs, and hardware. You will be better off buying a set of aftermarket heads complete.


Big Red N.C.

 

[happy]

i agree, he needs to get with his machinist, and come up with some solid nrs, push rod height, if never done before, i'd leave it to the machinist.. i use the lunite checker.. for the first timer, it gets confusing, and the instructions with the checkers are at best vauge.. once youve done it with someone that knows what there doing, that would be all the training necessary.

 

[Siddhi]

Yes we are going with new springs and push rod. I am basically turning the heads over to the machinst and he is going to give me the heads, cam, and push rods for me to put in. He will probably also come over and help me install everything as he does this everyday. I am sure I am not giving all the information when I say things because my buddy talks so fast. And it is such second nature to him. I will try to get the grind number from the cam and post that. I have just been spending my evenings pulling the motor.

I do trust my machinist buddy as he builds a lot of race motors for cars, bog trucks and boats. He has a very large following here in our small town and has been building these motors for as long as I can remember. It is always nice to get multiple opinions because I obviously do not know what I should go with and you guys have steered me in the right direction in the past. So I will get the grind number and post that and hopefully make sure I get going in the right direction.

As far as the bend for the pipes I will check into it but he seems to think it will work because we both have TRS drives with transmissions. He said that if I had a bravo then I would not have a transmission and they would be different. But I will double check.

Well thanks for the advice and I will try to update this post very soon. I will know more by this weekend as I should have the motor out and can post the findings of the internals by then.

 

[vinny p.]

Yes we are going with new springs and push rod. I am basically turning the heads over to the machinst and he is going to give me the heads, cam, and push rods for me to put in.

Thats a real bad idea. You can not assume the push rod length. You have to check the length after the heads and cam are on the block. Post that cam # before you buy it.

 

[SneakyPete]

Have you gotten the motor apart yet? Please don't buy a cam yet, wait till you get everything else figured out. Decide what heads you will be using first. The cam really should be one of the last things to buy. Depending on how much work your heads need, you may be better off going to the aftermarket. Family and Performance boating built a stock bottom end 454 a few months ago, using a Comp cam, edelbrock heads, intake, and holley carb. Made great power, let me know if you are interested in the build and I will try and find the magazine.
One more piece of advice: Under no circumstances should you talk to Vinny on the phone. I had the same situation as you last year, 350 with water injestion. I wanted an easy fix, Vinny wanted a 383. Vinny got a 383. I wanted to spare $ where ever I could. Vinny wanted AFR heads with full roller valve train. Vinny got AFR heads with a full roller valve train.
All joking aside, you need to listen Vinny and Happy as far as the advice they give. You can skimp here and there, but there are things you can't skimp on, and where you take that boat 40 miles off shore, skimping in the wrong places could get you killed.
If you were injesting water, I would take a close look at the bearings to make sure that haven't been damaged due to water in the oil.

 

[bigsbetter]

Weather you go for big power or just a mild version over stock, a VERY IMPORTANT thing to do is make sure the parts you use are matched to work well together! If you just put in a big huge cam, it will run like crap. You can do a fairly inexpensive rebuild and it can run excellent if the parts are matched to work with each other. Almost any cam will 'fit' in the block, and any aftermarket gigantic huge port big flowing head will 'fit' and bolt on your engine, but it won't run well if it's not thought out and the correct/best parts chosen. 'Best' doesn't mean expensive, but rather I'm referring to numbers as far as flow and compression and lift and duration and port size and valve size and runner size and intake design and exhaust set up and so forth. All you'll have are frustrations and a bunch of expensive parts that don't work well with each other. Just because Vinny has a pair of killer flowing heads on his BBC doesn't mean the same set will perform well on your engine with your set up. I think you need to sit down and design the engine on paper first, or have someone do it for you, before you go and buy parts. If you want to go cheap and mild, then go cheap and mild,but just make it match and it will run as well as it should.

 

[happy]

lets talk about exhaust... first off you have a checkmate, and your looking to buy pipes that were built for a cig.. noted you have a chance that cig, and checkmate put the holes in the transom in the exact same spot, or even close to the exaxt same spot.. its unlikely, and a bad buy unless you can fit the boat out before you purchase them.. the manifolds are cheap compared to the pipes.. and no 2 boats are the same. and i promise you if you call gill, stainless or cmi.. they are going to ask you for tail pipe measurments.. before they build them.. in all the boats over the years that i've tried to make pipes work from another boat, it didn't work.. or it worked for a bit..

here is the deal;; the two holes for the transom exhaust change with x dimension as well as other facters, you will fight to get a pipe on, then, you'll have a bend in the hose to your tip, then you'll burn a hose and spray exhaust and water all over...

do not use short pipes.. or risers as they call it.. even a stock 454 330hp may revert.. this is a well known fact.. notably stainless has pulled them from the market for quite a while now.. not worth buying..

 

[vinny p.]

Hey... Whats all this Vinny stuff!! You guys are just mad because I made you spend a few dollars. I know you guys are just messing around, or at least I hope so.. By now, you guys know that I am an anal pain in the a$$ and research things to death before buying anything. Remember, research twice and only pay once. Shoot from the hip, buy the first parts you find and you will find yourself buying parts again. Performance marine engines have a need and demand for the best parts you can get. Never skimp. If your budget doesnt allow you to get all your parts at one time, take your time and gather your parts a little at a time. Just dont assemble anything untill you have everything. I have seen assembled short blocks rust up while sitting in the garage waiting around.


Happy,

As usual, I agree with you. I cant emphasis enough the need for good exhaust. As you know, I have had enough of wet exhaust systems. Full dry is the only way to go. No more reversion for me.

 

[Big Red]

GOOD EXHAUST

COMPLETE MATCHED VALVE TRAIN springs, rockers, push rods, retainers, cam, lifters

STEEL CRANK AND GOOD RODS

FORGED PISTONS

YOUR HEADS NEED TO FLOW THE DEMAND OF YOUR CAM IF NOT PICK A SMALLER CAM OUT OR BUY BETTER HEADS

HUDGE CAM AND FLOWING HEADS NEEDs A BIG CARB AND GOOD INTAKE

What I am trying to say is becarful on how big of a cam you want unless you are willing to go all the way to make it perform properly. The bigger the cam the more your going to spend on the bottom end, heads, intake and carb. Alot of big lift cams like compression and that means high octane not just 93.

 

[Siddhi]

First off thanks for all the advice! I have not purchased anything as of yet. Everything my buddy has been talking to me about is just that, talk. I plan to have the motor out this weekend. Then my buddy plans to go through the motor with me. I understand completely about making sure things match and works for my situation. I am a motorcycle mechanic and most of my knowledge is in 2 stroke land. I have been racing 2 strokes for about 11 years. Even though they are a dying bread. I have built a ton a race bikes and I understand research and making the right choices the first time. That is why I am on this board. I really appreciate everyones help. I have also spoke with the boss (the wife) and told her that it seems that the motor rebuild will take more than I was hoping to spend. Her being the understanding woman and she loves the boat as much as me understands we will need to spend what we have to in order to do it right. Plus I told while I am there....... we can add some performance as well. So I got the nod to do whatever I need to. Plus she knows I take it offshore most of the time.

With that being said ultimately I want to make sure it will be reliable. That is why I have chosen to go ahead an tear it down now. I normally spend most of my time in the Gulf of Mexico and offshore. We love to just take it joy riding and I fishing as much as possible. The boat was running as normal as it has since I bought it but I never felt it was running competely right. We also spend at least 3 days a month during the summer on the river and skiing. Needless to say the boat gets used heavily.

So I would like to make sure whatever choices I make will have those thoughts in mind. As far as skiing the boat always did great pulling skiers, tubers, and wake boarders. Since I have chosen to go ahead and tear the motor all they way down my buddy also mentioned we could stroke it to a 496. What are your thoughts on that? He said it would give me mostly more torque and low end. He has a crankshaft balancer and he said it would not take long to balance a new crank and put in some new connecting rods and pistons while I was there. He is guessing that with my leaking risers that I do have water injestion and he said I will probably have to bore the cylinders anyway. These are all just thoughts and I plan to spend the money I need to in order to make it right. However with his connections and abilities I can save some money.

He is also aware that I want it to last and I do not want to have to redo this in a year or so. Like I have said before I trust him and I believe he has my best interests at heart. He has just been given me ideas for me to chew on. So I try to relay them here for everyone to comment on. However, in the end I want to do what is best for the conditions I use my boat.

As far as the exhaust is concerned I can easily test fit them before I buy them. If they work then great if not then I will cross taht bridge when I get to them. He did say that it does not mix the water in the exhaust until it is about a foot from the end. They are long pipes. If that makes sense.

 

[Siddhi]

Hey everyone,
I pulled the motor out today and I have it torn down. From what I see the cylinders all look very good and there is no pitting or rust or marks at all. So that is a good sign. The heads actually look pretty good also. That is just at frist glance. I plan to have my buddy come by tomorrow evening and tell me what he thinks about it. But I just wanted to update for now. I post when I know more.

 

[Siddhi]

How do you find the engine info? I found the serial number tag and was wondering if I could look it up somewhere. I went to www.mercurypartsexpress.com but it said my serial number was not found. So I am wondering if I put it in right. My tag had 7 digits D8xxxx and then on the next row in the middle it had an L. Do I add a 0 in front of the first 7? The number cam back as a LH bobtail. Just curious! Thanks!
-B

 

[Siddhi]

Well my buddy came by last night and took a look at everything. He said it had early signs of water ingestion but that I caught it before anything was hurt. He said the cylinders looked great. He said the Heads looked pretty good also. He did say that it looks like it was running fat. He recommended doing a vacuum test on the heads to see just how bad they were and then doing a valve job to refresh the heads. He said that it is the oval port heads and that we definitely should not go with the first cam I was talking about. He said that those heads do not flow that much and it would not be a good idea to go with a large cam like that. He said he would probably just put a very mild cam in it with some heavier springs to bring up the RPM some and stay with a flat tappet. Then just go back together like that. He said without spending a lot more money that might be the best choice. He told me that I could maybe pick up a few hundred more RPM safely that way without spending a ton of money. He said to do it right I would need at least new heads (rectangle port) and then I could think about putting a bigger cam in. Which in turn would probably mean new pistons because with the higher duration of a bigger cam the valves sometimes tend to touch the stock pistons before they are on their way back down. He said some people will grind the stock piston to make the valve indentions a little bit wider but he does not recommend that because it throws off your balance. Plus not to mention all the other parts like push rods, rocker arms, lifters, etc. He said we could still change it to a hydraulic roller but still go with a mild cam. He said the stock lift is about .460 / .480 and the stock duration is about 213 / 215 on a 114* Lobe Separation. So he was saying we should go with something in the .510 maybe up to a .550 lift range and a around a 223, 224ish duration range and a 115* Lobe Separation. He said that was about where the 454 mag is. These where just numbers off the top of his head and he would have to look up in his book what we would really go with. I am not really sure what all the numbers mean.

So here is what I plan to do. I plan to at least change the crank and cam bearings and re-ring it since I am pretty much there. I plan to change the Carb to something more fitting and do a valve job to get the heads back in shape. I also plan to change the exhaust as my manifolds and risers are in bad shape. I would like to add a little more top-end. I currently run 50gps and would like to get it around 60gps if I can without too much trouble. I guess my question is what do you guys think I should go with at this point? Is there any benefit to changing it over to a hydraulic roller? Can I get much gain from doing so? Should I spend the money and buy new heads and try to do everything I want to do now. And if I go that route what is the round about number I would spend? He told me that the Checkmates get hard to handle when you start running them around 70 mph or higher. He said they are great boats but do not like to go real fast. He said around the speed I am at is more ideal for them anyway. He said the boats tend to lift up and sort of float when you start to get them going real fast (remember I mostly spend my time in the Gulf of Mexico. The seas are normally 2 to 4 ft on average. He knows what type of water we have around here and that is where his experience with them is). Is that true? He said they like to chine walk, which makes them tough to control.

I have the motor out. The wife said we should do whatever at this point. I would be interested in spending around $2,000 – $2,500. Can I do anything worth wild with that amount of money? Or should I just go back with pretty much stock and live with what I have? I hope I have made enough sense at this point to get some good advice. If you need anything else from me just ask. Other than that I hope I covered everything enough.
Thanks for the help!

 

[vinny p.]

He told me that the Checkmates get hard to handle when you start running them around 70 mph or higher. He said they are great boats but do not like to go real fast.
I have the motor out. The wife said we should do whatever at this point. I would be interested in spending around $2,000 – $2,500.

You need a new mechanic!! What the hell is he talking about? I personally know of 3 Checkmates that run over 100 mph regularly with no handling issues. Mine runs in the mid 80's and handles the ocean with no problems. Now dont get me wrong , they are rigged to do this. No boat should run those speeds without full hydraulic steering, good tabs, etc.. I am not a believer in that ridiculous cable steering system that comes on most boats. That system is good for a slow cruiser, not for speed.

I dont want to burst your bubble, but with that budget, you cant expect to get any kind of a decent rebuild, let alone a new exhaust system. A set of inexensive manifolds and risers will cost you that much alone.

 

[SneakyPete]

He is generalizing on the handling of Checkmates, assuming they all have similar hull designs... very bad. As far as speed goes, roughly figure on 15-20hp per mph increase in speed. I picked up 16 mph after about 220hp increase. I found that magazine, they used Edelbrock heads, Air gap intake, and a Comp Roller. I will get you the specifics later. That maybe the cheapest way to go.

 

[Siddhi]

Vinny,
Well it is obvious that at this point any money I plan to spend is not enough for you. I have asked for suggestions and all I get from you is no spend more money you cannot do it for that. This will cost that alone or you need a new mechanic! SUGGESTIONS???? If I have to spend more money then that is what I will do! However I do want to keep it as cheap as I can. Because who goes out and says "I want the most expensive parts no matter what" No one! I have not heard anything from you about if I should use my current heads, what type of intake to look for, what type of exhaust for that matter, What type of cam (if any), or a suggestion to just go back to stock, or a budget I should prepare for! All I have heard is you downing my friend the mechanic, you telling me that no matter what money I have "would like to stay within if I can" just simply is never going to be enough. Bottom line! I want to put my motor back together and try to gain something if it is possible. If it is not then tell me that or give me a ball park price that I know what I need to spend (I am still just as blind about how much this will cost me as I was when I started this job) I want it reliable over all. I have posted all my findings and I have done what was asked of me to this point. Now that I am ready to move forward you simply have nothing proactive to say. I know there are ways to find good parts without paying an outragous price for it.

I was over at my buddy's shop yesterday and he was building an engine for a Pro-Stock race car. I know and trust his judgement and at least he tries to help. I do not know anything about you or what you do. So from here on out I do not need ANYMORE help from you! Oh and does the boats you talk about run on a lake or river or are they on the ocean? I would bet in a lake! Personally I would like to see you run 100mph in the gulf in our seas in a 25' convincor. You would have more balls than anyone I know! And don't tell me that Lake Ontario gets as big as the Gulf down here. Anyone that has truely run on our waters will tell you there is no comparison. That is what MY BUDDY IS TALKING ABOUT. Which I did mention!

Anyway I thank everyone that HAS TRIED to help me and I am sorry that I had to vent. I am not some young punk that will take Vinny's disrespectfulness any longer. In fact this post is probably not allowed so I will remove myself from this board and take care of my engine problems myself. I know very much how to do reseach and you can bet your bottom dollar it will be right and I will spend whatever is needed. Which Vinny has overlooked me saying several times.

Oh and Vinny don't waste your typing skills on a response as I will not longer be coming to this board! But I am sure you will type something useless!

Goodbye all sorry you have such a jackass on this board with you!

 

[bigsbetter]

Wow... I don't know what to say...or even if I should. Vinny is a very respected member here, but I also see where this guy is comming from.

 

[Chris E]

Wow... I don't know what to say...or even if I should. Vinny is a very respected member here, but I also see where this guy is comming from.

Really? i don't understand where he is coming from at all. the fella is quick enough to bend our ears but when he doesn't like the answer he gets pissy. Vinny's point is simple - do it right once. It is cheaper in the long run. but that's his choice, if he is going to be cheap and expects a 10 mph increase in speed for 2500 he's on something.

It's simple really, if you can't do it right don't do it at all especially if you are playing on the ocean. sell the boat and go golfing, its cheaper. In the meantime, Vinny is owed an apology and so is everyone else for that matter!