Good, honest advice wanted.
11-05-2002, 09:03 AM
#31
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I`ve been doing a little research on all of this, asking several different resources of their opinion. Of course, I`ve received several different answers. I don`t want to throw money at this and see what happens. I would like to see good results on first try. I know this has cast pistons and crank, so I want to keep it at 5000 rpm or less. I also don`t want to invest a ton of money or else I would just step up to a Procharger or a 502. I feel like I have outlined a pretty good plan. I am still reluctant on 2 items: The camshaft and carb choice. As far as cam, I wanted to run this 502/502 cam mainly because I thought it was in the ballpark of what this engine would like and the fact that I can get a crate motor "pull-out" camshaft for $100. Do you guys have a particular cam that you would recommend? What are the specs? The Edelbrock 750 Marine carb was recommended to me because of it`s low price (compared to Holleys) and it`s reliability. I was also told it would get better gas mileage as compared to a Holley. I am familiar with the AFB design and know how to tune them. I am also quite familiar with Holleys. If not Edelbrock, what would you run? Is the Merc distributor a good choice or should I just get a Mallory or MSD? HEI? I kmow where I can get an ignition from a `97 7.4 Carb engine. Would that be OK?
THANKS FOR ALL THE ADVICE GUYS!!!!
THANKS FOR ALL THE ADVICE GUYS!!!!
11-05-2002, 09:24 AM
#32
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If I were you I would stick with a 800 holeey then when your ready to upgrade you already have the carb......I run a MSD but the thunder bolt works fine....cams????
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If your boat has a sail do you ride a horse to the ramp?
If your boat has a sail do you ride a horse to the ramp?
11-05-2002, 09:49 AM
#33
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this is a gm stocker engine...with stock merc parts that surround it. meaning your gimbal and transom ass...my guess is you do not have offshore engine mounts, nor external steering?
you have not listed what application this is for yet? or have not made mention of any testing? Who will build this engine?...Who will dial it in? what are you going to do for an ignition system? the distributor is only one of the parts you will need. what ignition curve will you use.
as i told Jay prior to his 330 mods....your on a budget. you do not have the first hand knowledge of how to get this done. this may just return to bite you in the ass...i guess you really have to look at if enjoy boating more or working on the boat? have you assessed the bottom of the boat??? measured your X-dimension?
read this about how jay 330 project went down! LOL
http://www.offshoreonly.com/forum/sh...ghlight=jayl13
you have not listed what application this is for yet? or have not made mention of any testing? Who will build this engine?...Who will dial it in? what are you going to do for an ignition system? the distributor is only one of the parts you will need. what ignition curve will you use.
as i told Jay prior to his 330 mods....your on a budget. you do not have the first hand knowledge of how to get this done. this may just return to bite you in the ass...i guess you really have to look at if enjoy boating more or working on the boat? have you assessed the bottom of the boat??? measured your X-dimension?
read this about how jay 330 project went down! LOL
http://www.offshoreonly.com/forum/sh...ghlight=jayl13
11-05-2002, 10:19 AM
#36
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Comp cams makes a couple in their extreme marine series that would work well. I think they are XR-264-HR or XR-270-HR. Going to a larger cam won't make any more power at 5000 RPM and under. The Edelbrock carb is fine. If that Merc distributor is a Thunderbolt V it will have a rev limiter and you may have to change the module out to get 5000 RPM unless it's from a magnum. If it's a Thunderbolt IV it will work fine.
11-05-2002, 10:27 AM
#37
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Madmaxx, you're are correct in that the larger valves are tight. You can, however get them in just fine by doing a little grinding in the chamber. They are more shrouded than an open chamber head for sure, though. You can lay the chamber back some and get them opened up. You give up a little compression, but the air flow increase more than offsets it. You also must replace the exhaust seats for the larger valves.
11-05-2002, 10:49 AM
#38
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Originally posted by audacity
...my guess is you do not have offshore engine mounts, nor external steering?
you have not listed what application this is for yet? made mention Who will build this engine?...Who will dial it in?
....your on a budget. you do not have the first hand knowledge of how to get this done.
[
...my guess is you do not have offshore engine mounts, nor external steering?
you have not listed what application this is for yet? made mention Who will build this engine?...Who will dial it in?
....your on a budget. you do not have the first hand knowledge of how to get this done.
[
You don`t know what my budget is and you have no freakin idea of my mechanical abilities. So how can you tell me I have no knowledge of how to get this done? You don`t know me....
I never said I was rebuilding this engine. It has very low hours on it now. For the record, I honestly can`t tell you how many engines I have built over the past 20 years, more than enough to get this job done with no sweat! I was merely on this forum to get opinions/ideas. You come on and make me out to be some uneducated moron. I`m not building a race boat or a race engine and will never pretend to be doing so. So lighten up a bit please.
11-05-2002, 11:27 AM
#39
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sorry if i'm coming off the wrong way...
"So how can you tell me I have no knowledge of how to get this done? You don`t know me.... "...just from what you have actually posted...you never answered the question(s) what application is this going to be it?...what were your #'s from your pre mods and after...why is it you have spent $$ and time and seen zero results?...what do the #'s tell you? ...you say... "I don`t want to throw money at this and see what happens. I would like to see good results on first try."...so why didn't you apply this theory to your first mods?
I NEVER questioned your mechanical abilities WHATSOEVER...knowledge of how a system works in a real world marine enviorment and mechanical abilities are very different.
really...HONESTLY.... i'm not trying to be a dickhead....i'm just trying (maybe verbalizing the wrong way) to save ya the time and $$$...
think about this.....if there was a race class for your exact boat configuration....what would you be wlling to bet that the racers would get better numbers out of it that the mods your willing to try? all at zero compromise to the engines integrity.
ps...i'm in houston TX all the time! maybe i'll see ya out there??!!! have fun!
"So how can you tell me I have no knowledge of how to get this done? You don`t know me.... "...just from what you have actually posted...you never answered the question(s) what application is this going to be it?...what were your #'s from your pre mods and after...why is it you have spent $$ and time and seen zero results?...what do the #'s tell you? ...you say... "I don`t want to throw money at this and see what happens. I would like to see good results on first try."...so why didn't you apply this theory to your first mods?
I NEVER questioned your mechanical abilities WHATSOEVER...knowledge of how a system works in a real world marine enviorment and mechanical abilities are very different.
really...HONESTLY.... i'm not trying to be a dickhead....i'm just trying (maybe verbalizing the wrong way) to save ya the time and $$$...
think about this.....if there was a race class for your exact boat configuration....what would you be wlling to bet that the racers would get better numbers out of it that the mods your willing to try? all at zero compromise to the engines integrity.
ps...i'm in houston TX all the time! maybe i'll see ya out there??!!! have fun!
