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martini
12-16-2004, 03:04 PM
Has anyone considered, when carb replacement is required, using Edelbrock's marine carb? I'm mostly just curious because this was the route I chose to take when I had to make that decision. I have to say that I am very pleased with it and it's simplicity makes it even more attractive. I guess my question is, why don't we see more of this? Longevity argument aside(I have had no issues) why the bias to get the Holley 4160? The Edelbrock, with a tuning kit and extra gaskets, is still less expensive than the Holley. Just something I noticed with regards to carbs and our precious ski boats!

east tx skier
12-16-2004, 03:55 PM
I suppose it's because Holley was OEM on these boats and the 4160 was the more reliable and still available Holley carb. Second reason is probably that DIM stocks the Holley and they're a pretty popular source. I paid $419 for a new one last May (please disregard any previous posts in which I said $319 --- sorry).

martini
12-16-2004, 04:48 PM
That is probably true and I guess price is really not an issue for most people who own boats, but I paid about a $100 less w/the tuning kit and gaskets. It fit perfectly and once I dialed it in, has been rock solid since. Only time will tell if longevity is an issue. I guess we will see. If you are a do it your selfer, such as I am, this carb makes more sense and the instructions it came with were excellent. You also don't have to remove it or fuel bowls from the engine to make adjustments to float level and jets. It worked for me and I think it looks coooool on the engine!

east tx skier
12-16-2004, 05:19 PM
That's just it. I'm not that much of a do-it-yourselfer. The Holley I bought came pre-tuned for the 351W. The only thing I've done to it is adjust the idle.

As for longevity, I have information from an owner of a 4160 who went around 10 years before selling his boat and never required a rebuild. He just ran it about once a month during the winter (and, obviously, regularly during the summer). I've decided that it's not too much trouble for me to do the same (draining afterwards during the winter).

crdickey
12-16-2004, 05:37 PM
If you just installed an Edelbrock manifold you'll need to tune you carb to match the increase air flow of your new high performance manifold.

Changing one without adjusting the other doesn't give you the HP boost you are looking for.

Edelbrock sells performance packages which are dyno match components, intake, carb, cam and heads. This is the best way to breath life into an older motor.

I did this to a 1987 351W PCM motor and basically it was a bolt on 150HP increase. Cost me $1,500.00

All this is posted on Edelbrocks website. This link should take you to the correct page. http://www.edelbrock.com/automotive/ford_1g.html

The only think that needs to be marine is the carb, everything else is the same as the automotive.

martini
12-16-2004, 05:50 PM
EastTX,

Not that it will be a concern for you, since your Holley was tuned for your setup(High Output set up with the GT40 heads), but in general, more air flow into the engine will require more fuel as well. Like I said, the intake shouldn't shoot you off into dangerously lean. But, I wonder what other performance you could gain with a little carb tuning to your new set-up? If this was already addressed by your mechanic, I apologize for sounding any alarms. It probably really wouldn't matter, unless you run at WOT all the time. I know that when I initially installed the Edelbrock on my boat, it was set way too lean. It would get hot at moderate cruising speeds, miss on full throttle, and generally run crappy. I enriched it 2 stages at WOT and 1 stage in the cruise range and all was good. Just a little something for you to chew on.

martini
12-16-2004, 05:51 PM
crdickey beat me to the punch. However, on that link you would substitute carb number 1409 in place of the ones they have listed.

east tx skier
12-16-2004, 06:03 PM
Well, the boat's put up for now. When I have a chance to run it, I'll see what's what. Not alarmed, just glad to have good info.

My mechanic was of the opinion that Holley's tend to run a little rich anyway, and since the manifold wasn't a drastic change over stock that it would probably do alright. So the plan is to take it out, run it, and bring it back to rejet, retune, or whatever is necessary (if necessary) after we have a field test.

Sounds reasonable to me. Looking at the weather, Saturday is supposed to see the low 60s. :steering:

Storm861triple
12-16-2004, 07:32 PM
Edelbrock sells performance packages which are dyno match components, intake, carb, cam and heads. This is the best way to breath life into an older motor.

I did this to a 1987 351W PCM motor and basically it was a bolt on 150HP increase. Cost me $1,500.00

All this is posted on Edelbrocks website. This link should take you to the correct page. http://www.edelbrock.com/automotive/ford_1g.html

I'm sorry, but I'm going to have to raise the BS flag all the way to the top of the pole BS flag pole here.

No WAY on this planet did you get 150 more hp from a cam and intake. I don't know where you got that number from, but that figure belogs on planet Jupiter, not Earth. You MAY have gotten as much as 30-40 hp if you're lucky, but no way did you see 4-5 times that much.

Again, for all reading this thread, a cam and intake will net you maybe 30-40 horse at the most!

Storm861triple
12-16-2004, 07:50 PM
As for the whole Edelbrock vs Holley debate, the holley is a better carb. I do agree that the Edlebrock has SOME FEATURES that are nice and well thought out, but it also has some terribly engineered and very cheap features as well. Examples are the goofy "flapper door" thing that Edelbrock calls vacuum secondaries. Another is the terrible veturi design (the secondaries don't even have a concentric shape!). Another is the fact that the throttle shafts are loose in their bores right from the factory! Built in vacuum leak! Lastly, the float bowl design lends itself toward fuel slosh and flooding during hard cornering and off angle operation (I thought this was a PERFORMANCE carb??)

I just went through all this crap on my 420 hp Camaro, and ended up resolving all the above mentioned issues with a Holley 4150, 700 CFM mechanical secondary carb. Much, much better, even if I do spill a little fuel when jetting it. (something you should only have to do once).

I personally prefer the 4150 over the 4160 because the 50 has a metering block for the secondaries which allows you to jet the secondary A/F ratio. The 4160 has a metering PLATE which is no longer available in diferent orfice sizes so tuning of the secondary A/F ratio is not an option.

Having said that, and a word about reliability, I still have the original 4160 on my engine, 12 years old w/500 hours and it still works absolutely flawlessly. All carbs are reliable if you just keep them clean and maintained.

east tx skier
12-16-2004, 09:16 PM
Hi Thomas, I was just reading some of your comments on skiboathelp.com about the performer versus the performer rpm versus the performer air gap, etc. Since which one I went with is a done deal, do you have any predictions as to what adjustments, if any, will need to be made to the carb?

Storm861triple
12-16-2004, 11:56 PM
I doubt you're going to have to change much if anything. Honestly, thie thing would probably be just fine if you just go use it. BUT if you want to KNOW that it really is perfect, there's only one way to tell, and that's to go out and do some "jet runs". You'll need a vacuum gauge and a plug wrench.

To do this job thoroughly you're going to need to run the engine for at least a minute at several different throttle positions.

The first thing you need to do is find out what power valve you have. The number will tell you at what manifold vacuum level the power valve opens and enrichens the A/F ratio.

Then hook your vacuum gauge to manifold vacuum.

Run the boat on an open stretch of water a speed well above idle but that yeilds a vacuum reading higher than the rating on the power valve. Also you don't want to apply enough throttle as to start opening the secondaries; You might want to have someone watch the carb as you drive. Run it like this for at least one minute, at that same throttle position, and then w/o changing the throttle position, turn the key off. When the boat comes to rest, pull the plugs and read the color, etc. If they are lean, you need to increase primary main jet size. If they are rich, decrease.

Next you want to run at a throttle position that results in a vacuum reading below that rating on the power valve. Again, for at least one minute, the cut it of clean again, and pull plugs and read them. The color indications at this point will tell you if your power valve is coming on too soon; if it's too rich.

Last, you want to run at WOT for at least a minute and again cut it off clean. Read the plugs again. Since you have a 4160, if you need to adjust the A/F ratio now, you can TRY to find a different metering plate, or you can try to "cover" the problem by changing the primary main jets and power valve as a compromise. Remember that at WOT it's drawing fuel from 4 main jets simultainiously; the two primary main jets, and the two secondary main jets(or in the 4160's case, the metering plate). So you will affect the overall A/F ratio by changing the primaries. You just then need to figure out how to change what that does to the part throttle A/F ratio when you are only operating on the primaries only (cruising).

Is this clear? Or is it mostly mumbo-jumbo for ya? :)

martini
12-17-2004, 01:47 AM
The 1409 I have has mechanical secondaries not vaccuum. Yeah, I would be skeptical about the above mentioned upgrades as far as real world numbers are concerned. With regards to fuel slosh, I haven't experienced any such issues with flooding or otherwise. The Holley I originally had gave me no more top speed or acceleration than my current set up. In fact, I feel this carb is more linear in it's accelaration compared to the Holley. I do however agree with you about maintenance. It definitely has a lot due with longevity of engines, marine or otherwise.

east tx skier
12-17-2004, 10:31 AM
Thomas, thanks a bunch for the info. It's not mumbo-jumbo, but maybe not something I'd undertake myself. Good info to have if I need it though. Vince at skidim just told me that, as you mentioned, it will probably be fine as is, or perhaps, might need to be slightly adjusted to run richer. I'm going to try to run it tomorrow since we're expecting sunshine and 60 degrees. I'll update when I have something to report..

H20skeefreek
12-17-2004, 05:17 PM
my question is, does anyone know any really good resources for how to rebuild a Holley? The mechanic i've been trying to reach won't call be back, and I'm planning on skiiing on new years day. I've got the carb off and in a box. So, I need to just rebuild this thing myself.

east tx skier
12-17-2004, 05:25 PM
Here ya go.

How to rebuild a Holley Carb (http://www.chevyhiperformance.com/howto/45798/)