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View Full Version : Best intake for old's 455?



73maverickjet
08-23-2006, 04:16 PM
Hello everyone. I'd like to get some opinion's on the best intake for a mild built 455, jet boat engine of course. Any feedback would be great!! Thanx!!:confused:

northeastcat
08-23-2006, 05:58 PM
Many times we have run the Eldebrock with good results on the 455. The most recent 455 we built was for a 4spd car and the customer supplied the intake it was an old Offenhauser Port-O-Sonic and it worked damn good. Pulled like a frieght train and there seemed to be no end to the gear expect for the tach yelling at me to shift. I dont know if they even make this intake anymore but if they do I would definatly consider it.

73maverickjet
08-23-2006, 11:49 PM
Did it clear a hei distributer. I heard they have clearence problems with the hei. Thanx for the replie.

northeastcat
08-24-2006, 04:22 PM
Actually I'm not sure about that as he also suppllied an Accell Distributor too. The accell might have been a little taller but I dont remember it being much different looking then the regular HEI.

The Big Al
08-24-2006, 04:33 PM
This greatly depends on the rpm range you need.

I guess we want a lot of torque for the olds?

In regards to boat engine.

Al

The Big Al
08-24-2006, 04:38 PM
http://www.edelbrock.com/automotive_new/mc/manifolds/images/2730.jpg

Edlebrock #2730

This is a great intake from 2500-6500rpm.

Good intake for a boat, cruising in the 3k range.

Good thing about this intake is availabilty, and it will clear for HEI.

And is a non-EGR intake

The Big Al
08-24-2006, 04:42 PM
<TABLE height=129 cellSpacing=0 cellPadding=2 width=745 border=1><TBODY><TR><TD width=316 height=98>
http://www.mondellotwister.com/dual-carb_air-cl.gif
</TD><TD vAlign=top width=415 height=98>
Dual Carb/Air Filter w/throttle linkage!
Offenhauser is the only manufacturer of Dual Quad intake manifolds for Oldsmobiles. Accepts two four barrel carburetors. Ideal for street rods and an impressive engine compartment, especially when they are highly polished. The low profile manifold allows this setup to fit under your stock hood. Dual air filters allow easy access to your individual carburetors. Call us today to order yours!
</TD></TR></TBODY></TABLE>Intake Manifolds
<TABLE cellSpacing=0 cellPadding=0 width=744 border=0><TBODY><TR><TD width=742>Porting options are available on most manifolds.</TD></TR></TBODY></TABLE><TABLE height=931 cellSpacing=0 width=746 border=1><TBODY><TR><TD vAlign=center align=middle width=91 height=129>http://www.mondellotwister.com/Man6109_small.gif (http://www.mondellotwister.com/Man6109.gif)</TD><TD vAlign=top width=479 height=129>4150 Mondello Posiflow
This all aluminum intake manifold for the 400-425-455 Olds engines has an open plenum large runner and is designed for high performance needs. Carburetor base fits a square bore Holley 850 cfm carb. Effective power range from 3000 to 6500 RPM. Can be used with stock or HEI distributors (some minor modification may be required). </TD><TD vAlign=top align=middle width=162 height=129>
<!--webbot bot="jacpur" startspan CLIENTSIDE PREVIEW="<img border=0 src=""&quot;C:\WINNT\jacpurchase.gif&quot;>" --><FORM action=http://www.justaddcommerce.net/o/order.dll method=post><INPUT type=hidden name=merchantname> <INPUT type=hidden value=0001-4187-0322-5631 name=merchant><INPUT type=image src="http://www.mondellotwister.com/buybutton.gif" value="Add to Shopping Cart" name=additem><INPUT type=hidden value=4150 name=sku><INPUT type=hidden value=$399 name=price><INPUT type=hidden value="Posiflow Manifold" name=description><INPUT type=hidden value=25 name=weight><INPUT type=hidden value=no name=ship_free><INPUT type=hidden value=no name=jac_minimumquantity><INPUT type=hidden value=yes name=taxable><INPUT type=hidden value=no name=jac_no_shopping_cart><INPUT type=hidden value=yes name=jac_disallowfractionalquantity> <TABLE name="OptionTable"><TBODY><TR><TD><INPUT type=radio value=0;Standard;1 name=jac_prodoptions0 rname="manifold">Standard </TD><TD>$399.00</TD></TR><TR><TD><INPUT type=radio value=+200;Stuffer;2 name=jac_prodoptions0 rname="manifold">Stuffer </TD><TD>$599.00</TD></TR><TR><TD><INPUT type=radio value=+200;Ported;3 name=jac_prodoptions0 rname="manifold">Ported </TD><TD>$599.00</TD></TR><TR><TD><INPUT type=radio value="+400;Ported w/Stuffer;4" name=jac_prodoptions0 rname="manifold">Ported <TD>$799.00</TD></TR><TR><TD> w/Stuffer</TD></TD></TR></TBODY></TABLE></FORM><!--webbot bot="jacpur" i-CheckSum="51495" endspan -->
</TD></TR><TR><TD vAlign=center align=middle width=91 height=92>http://www.mondellotwister.com/Man6108_small.gif (http://www.mondellotwister.com/Man4500Cone.gif)</TD><TD vAlign=top width=479 height=92>4500 Mondello Posiflow This all aluminum intake manifold for the 400-425-455 has an open plenum large runner and is recommended for competition use only. The improvements to this manifold include the use of 4 paravanes at the bottom of the plenum to direct the gas/air mixture through the runners in an even distribution pattern with a minimum turbulence factor. Can be used with stock or HEI distributors (some minor modification may be required). </TD><TD vAlign=top align=middle width=162 height=92>
<!--webbot bot="jacpur" startspan CLIENTSIDE PREVIEW="<img border=0 src=""&quot;C:\WINNT\jacpurchase.gif&quot;>" --><FORM action=http://www.justaddcommerce.net/o/order.dll method=post><INPUT type=hidden name=merchantname> <INPUT type=hidden value=0001-4187-0322-5631 name=merchant><INPUT type=image src="http://www.mondellotwister.com/buybutton.gif" value="Add to Shopping Cart" name=additem><INPUT type=hidden value=4500 name=sku><INPUT type=hidden value=$399 name=price><INPUT type=hidden value="Posiflow Manifold" name=description><INPUT type=hidden value=25 name=weight><INPUT type=hidden value=no name=ship_free><INPUT type=hidden value=no name=jac_minimumquantity><INPUT type=hidden value=yes name=taxable><INPUT type=hidden value=no name=jac_no_shopping_cart><INPUT type=hidden value=yes name=jac_disallowfractionalquantity> <TABLE name="OptionTable"><TBODY><TR><TR><TD><INPUT type=radio value=0;Standard;1 name=jac_prodoptions0 rname="manifold">Standard </TD><TD>$399.00</TD></TR><TR><TD><INPUT type=radio value=+200;Stuffer;2 name=jac_prodoptions0 rname="manifold">Stuffer </TD><TD>$599.00</TD></TR><TR><TD><INPUT type=radio value=+200;Ported;3 name=jac_prodoptions0 rname="manifold">Ported </TD><TD>$599.00</TD></TR><TR><TD><INPUT type=radio value="+400;Ported w/Stuffer;4" name=jac_prodoptions0 rname="manifold">Ported <TD>$799.00</TD></TR><TR><TD> w/Stuffer</TD></TD></TR></TBODY></TABLE></FORM><!--webbot bot="jacpur" i-CheckSum="40463" endspan -->
</TD></TR><TR><TD vAlign=center align=middle width=91 height=156>http://www.mondellotwister.com/Man2151_small.gif (http://www.mondellotwister.com/Man2151.gif)</TD><TD vAlign=top width=479 height=156>2151 Edelbrock Performer
Dual plane aluminum intake manifold for 400-425-455 Oldsmobile street and high performance applications operating in the idle-5500 rpm range. Our VT-581 Aluminum Valley Tray and IG-505 Intake Gaskets are recommended for this manifold. For marine and off-road applications, use HR-350 Heat Riser Block Off Plugs or HR-351 S/S Heat Riser Block Off Plates. Will work with HEI distributors. Will not fit Toronado or 4-4-2 Ram-Air scoop without hood modifications. Center divider can be cut for an additional charge. Use #2732 Carb Plate for square flange Holley Carburetors. </TD><TD vAlign=top align=middle width=162 height=156>
<!--webbot bot="jacpur" startspan CLIENTSIDE PREVIEW="<img border=0 src=""&quot;C:\WINNT\jacpurchase.gif&quot;>" --><FORM action=http://www.justaddcommerce.net/o/order.dll method=post><INPUT type=hidden name=merchantname> <INPUT type=hidden value=0001-4187-0322-5631 name=merchant><INPUT type=image src="http://www.mondellotwister.com/buybutton.gif" value="Add to Shopping Cart" name=additem><INPUT type=hidden value=2151 name=sku><INPUT type=hidden value=$259 name=price><INPUT type=hidden value="Edelbrock Performer" name=description><INPUT type=hidden value=25 name=weight><INPUT type=hidden value=no name=ship_free><INPUT type=hidden value=no name=jac_minimumquantity><INPUT type=hidden value=yes name=taxable><INPUT type=hidden value=no name=jac_no_shopping_cart><INPUT type=hidden value=yes name=jac_disallowfractionalquantity> <TABLE name="OptionTable"><TBODY><TR><TR><TD><INPUT type=radio value=0;Standard;1 name=jac_prodoptions0 rname="manifold">Standard </TD><TD>$259.00</TD></TR><TR><TD><INPUT type=radio value="+50;Cut Divider2" name=jac_prodoptions0 rname="manifold">Cut Divider</TD><TD>$309.00</TD></TR><TR><TD><INPUT type=radio value=+200;Ported;3 name=jac_prodoptions0 rname="manifold">Ported </TD><TD>$459.00</TD></TR><TR><TD><INPUT type=radio value="+240;Ported/Cut Divider;4" name=jac_prodoptions0 rname="manifold">Ported/ <TD>$499.00</TD></TR><TR><TD> Cut Divider</TD></TD></TR></TBODY></TABLE></FORM><!--webbot bot="jacpur" i-CheckSum="30445" endspan -->
</TD></TR><TR><TD vAlign=center align=middle width=91 height=155>http://www.mondellotwister.com/Man2730_small.gif (http://www.mondellotwister.com/Man2730Cone.gif)</TD><TD vAlign=top width=479 height=155>2730 Edelbrock Torker Open plenum aluminum intake manifold for 400-425-455 Oldsmobile high performance, drag racing and competition applications operating in the 2500-6500 rpm range. 2732 Adaptor Plate is required for square bore Holley. Our VT-581 Aluminum Valley Tray and IG-505 Intake Gaskets are recommended for this manifold. Will work with HEI distributors. Will not fit Toronado or 4-4-2 Ram-Air scoop without hood modifications. Cone installation and porting options are available. </TD><TD vAlign=top align=middle width=162 height=156>
<!--webbot bot="jacpur" startspan CLIENTSIDE PREVIEW="<img border=0 src=""&quot;C:\WINNT\jacpurchase.gif&quot;>" --><FORM action=http://www.justaddcommerce.net/o/order.dll method=post><INPUT type=hidden name=merchantname> <INPUT type=hidden value=0001-4187-0322-5631 name=merchant><INPUT type=image src="http://www.mondellotwister.com/buybutton.gif" value="Add to Shopping Cart" name=additem><INPUT type=hidden value=2730 name=sku><INPUT type=hidden value=$259 name=price><INPUT type=hidden value="Edelbrock Torker" name=description><INPUT type=hidden value=25 name=weight><INPUT type=hidden value=no name=ship_free><INPUT type=hidden value=no name=jac_minimumquantity><INPUT type=hidden value=yes name=taxable><INPUT type=hidden value=no name=jac_no_shopping_cart><INPUT type=hidden value=yes name=jac_disallowfractionalquantity> <TABLE name="OptionTable"><TBODY><TR><TR><TD><INPUT type=radio value=0;Standard;1 name=jac_prodoptions0 rname="manifold">Standard </TD><TD>$259.00</TD></TR><TR><TD><INPUT type=radio value=+200;Stuffer;2 name=jac_prodoptions0 rname="manifold">Stuffer </TD><TD>$459.00</TD></TR><TR><TD><INPUT type=radio value=+200;Ported;3 name=jac_prodoptions0 rname="manifold">Ported </TD><TD>$459.00</TD></TR><TR><TD><INPUT type=radio value="+400;Ported w/Stuffer;4" name=jac_prodoptions0 rname="manifold">Ported <TD>$659.00</TD></TR><TR><TD> w/Stuffer</TD></TD></TR></TBODY></TABLE></FORM><!--webbot bot="jacpur" i-CheckSum="27325" endspan -->
</TD></TR><TR><TD vAlign=center align=middle width=91 height=1>http://www.mondellotwister.com/Man2810_small.gif (http://www.mondellotwister.com/Man2810.gif)</TD><TD vAlign=top width=479 height=1>2810 Edelbrock Olds Victor Manifold
Designed for the ultimate Pro-Street/Drag Race/Marine applications. This new Victor Manifold bolts right on the Edelbrock Performer RPM aluminum cylinder heads or stock cast iron heads for the 400-455 Oldsmobile engines. Uses a standard flange for an 850 cfm carburetor. We can modify this manifold to fit under stock hoods. (Will not fit without modification.) </TD><TD vAlign=top align=middle width=162 height=1>
<!--webbot bot="jacpur" startspan CLIENTSIDE PREVIEW="<img border=0 src=""&quot;C:\WINNT\jacpurchase.gif&quot;>" --><FORM action=http://www.justaddcommerce.net/o/order.dll method=post><INPUT type=hidden name=merchantname> <INPUT type=hidden value=0001-4187-0322-5631 name=merchant><INPUT type=image src="http://www.mondellotwister.com/buybutton.gif" value="Add to Shopping Cart" name=additem><INPUT type=hidden value=2810 name=sku><INPUT type=hidden value=$399 name=price><INPUT type=hidden value="Edelbrock Olds Victor Manifold" name=description><INPUT type=hidden value=25 name=weight><INPUT type=hidden value=no name=ship_free><INPUT type=hidden value=no name=jac_minimumquantity><INPUT type=hidden value=yes name=taxable><INPUT type=hidden value=no name=jac_no_shopping_cart><INPUT type=hidden value=yes name=jac_disallowfractionalquantity> <TABLE name="OptionTable"><TBODY><TR><TR><TD><INPUT type=radio value=0;Standard;1 name=jac_prodoptions0 rname="manifold">Standard </TD><TD>$399.00</TD></TR><TR><TD><INPUT type=radio value=+300;Ported;2 name=jac_prodoptions0 rname="manifold">Ported </TD><TD>$699.00</TD></TR><TR><TD><INPUT type=radio value="+149;Hood Mach;3" name=jac_prodoptions0 rname="manifold">Hood Mach </TD><TD>$548.00</TD></TR><TR><TD><INPUT type=radio value=+449;Ported/Mach;4 name=jac_prodoptions0 rname="manifold">Ported/ <TD>$828.00</TD></TR><TR><TD> Hood Mach</TD></TD></TR></TBODY></TABLE></FORM><!--webbot bot="jacpur" i-CheckSum="36625" endspan -->
</TD></TR><TR><TD vAlign=center align=middle width=91 height=63>http://www.mondellotwister.com/Man2811_small.gif (http://www.mondellotwister.com/Man2811.gif)</TD><TD vAlign=top width=479 height=63>2811 Edelbrock Olds Victor Manifold
Designed for the ultimate Pro-Street/Drag Race/Marine applications. This new Victor Manifold bolts right on the Edelbrock Performer RPM aluminum cylinder heads or stock cast iron heads for the 400-455 Oldsmobile engines. Uses an enlarged flange for a 4500 series carburetor. We can modify this manifold to fit under stock hoods. (Will not fit without modification.) </TD><TD vAlign=top align=middle width=162 height=64>
<!--webbot bot="jacpur" startspan CLIENTSIDE PREVIEW="<img border=0 src=""&quot;C:\WINNT\jacpurchase.gif&quot;>" --><FORM action=http://www.justaddcommerce.net/o/order.dll method=post><INPUT type=hidden name=merchantname> <INPUT type=hidden value=0001-4187-0322-5631 name=merchant><INPUT type=image src="http://www.mondellotwister.com/buybutton.gif" value="Add to Shopping Cart" name=additem><INPUT type=hidden value=2811 name=sku><INPUT type=hidden value=$399 name=price><INPUT type=hidden value="Edelbrock Olds Victor Manifold" name=description><INPUT type=hidden value=25 name=weight><INPUT type=hidden value=no name=ship_free><INPUT type=hidden value=no name=jac_minimumquantity><INPUT type=hidden value=yes name=taxable><INPUT type=hidden value=no name=jac_no_shopping_cart><INPUT type=hidden value=yes name=jac_disallowfractionalquantity> <TABLE name="OptionTable"><TBODY><TR><TR><TD><INPUT type=radio value=0;Standard;1 name=jac_prodoptions0 rname="manifold">Standard </TD><TD>$399.00</TD></TR><TR><TD><INPUT type=radio value=+300;Ported;2 name=jac_prodoptions0 rname="manifold">Ported </TD><TD>$699.00</TD></TR><TR><TD><INPUT type=radio value="+149;Hood Mach;3" name=jac_prodoptions0 rname="manifold">Hood Mach </TD><TD>$548.00</TD></TR><TR><TD><INPUT type=radio value=+449;Ported/Mach;4 name=jac_prodoptions0 rname="manifold">Ported/ <TD>$828.00</TD></TR><TR><TD> Hood Mach</TD></TR></TBODY></TABLE></FORM>
</TD></TR></TBODY></TABLE>

The Big Al
08-24-2006, 04:47 PM
Just take the part numbers, shop around with

Doug Herbert Performance http://www.dougherbert.com/
1-877-497-2787

Summit 1-800-230-3030

Jegs 1-800-345-4545

northeastcat
08-24-2006, 05:35 PM
Al,
Copy'n and past'n is nice but... I really think he was looking for some input from someone who actually had used a performance intake on a 455 and what by comparison would they know would work best for his application. As far as torque goes there will be an excess of that, it is a 455 Olds engine, the only thing in question will be where it comes in and when it peaks.

OldSleekOlds
08-24-2006, 05:42 PM
This is really interesting. You guys are making all kinds of suggestions......based on what? Your experience with a car engine....somebody else's experience that you heard about. If you were talking about an intake for a car, would you care if the car had a factory, stock exhaust system? Would that in any way influence your recommendation? Do you think a car will make the same power no matter what exhaust system is used?

You guys gotta be way smarter than that.

The exhaust system on a boat has more influence on performance than the exhaust system on a car. Your experience with car engines is helpful when working with a Marine engine, however you will NOT get the same result with the Marine engine that you got with a car engine.

For example, last Fall I replaced my Edelbrock Performer intake with a Victor. Good move, right. WRONG!! We made cam changes, valve timing changes, ignition timing changes, carb jet changes, it was on the Dyno for 2 weeks. My friend has a Dyno and we were determined to get 500 hp. We got 470 hp. The reason? We did it all with the complete boat exhaust system on the motor.

Oh yeah, the (port matched) Victor intake LOST 8 hp. We ended up with the Performer that we started with. We did pick up about 40 hp with a cam change.

I'm sure that more power can be gained/lost with Marine exhaust systems than is possible with any single carb intake change on a boat.

I'm still waiting for somebody to ask about the exhaust system on this motor.

northeastcat
08-24-2006, 06:03 PM
If any of that post was directed towards me I think you need to reread my first post, I said consider... I did not say, you HAVE to use this intake. I dont have experience with a 455 in a marine application and I did not state that I did. I know all to well what the exhaust can do for a marine engine, for that matter a bigger carb on a stock intake will yeild quite impressive results versed against some aftermarket intakes on certain marine applications, this I know and I have experienced it myself, yet again not with a 455 Olds. The reason I -suggested- the intake that I did was because it seemed to make a very impressive amount of useable torque and I felt that it might make a good intake on a marine engine.

OldSleekOlds
08-24-2006, 06:46 PM
The post is NOT directed at anybody. My intent is to get you ALL to think BEFORE you post.

Unless the person asking for help declares his degree of expertise on the subject, you should consider that he has none. If your suggestions are conditional, then you should state the conditions that will influence the situation.

I have NO interest in taking shots at anyone.

I think that when you suggest someone make a change on the basis of your experience with a car engine, you should make it clear that the same thing might not work for a Marine application. You might even say why....if you know.

Just trying to avoid misleading folks.

northeastcat
08-24-2006, 07:00 PM
One more time, I did not mislead anyone and I take it as a shot as you stating so. I said 'I would consider it'. I choose my wording carefully as to not mislead anyone.
It seems your the one with all the experience...:rolleyes:

The Big Al
08-25-2006, 11:03 AM
I'm speeking to the person who ask for advice.

RPM range of your engine has a great deal to do with your selection.

You should prefer a non-EGR intake.

That is why I posted the Edelbrock on first.

Now, yes there are several factors in your intake selection.
But being a Olds engine, and a monster torque engine, you will notice most all the intakes have same runners. Mostly changing the intake will save weight, reduce heat. A carb spacer 1' or greater will be a great benifit.

I do not see you below 2000 rpm or above 6000 rpm.

Al

The Big Al
08-25-2006, 11:07 AM
Al,
Copy'n and past'n is nice but... I really think he was looking for some input from someone who actually had used a performance intake on a 455 and what by comparison would they know would work best for his application. As far as torque goes there will be an excess of that, it is a 455 Olds engine, the only thing in question will be where it comes in and when it peaks.

I think you should check to see if that person has or has not used, built, or be around Olds engines.

But your a great automotive Machinest! So that makes you a performance expert.

What do I know???

northeastcat
08-25-2006, 11:16 AM
I think you should check to see if that person has or has not used, built, or be around Olds engines.

But your a great automotive Machinest! So that makes you a performance expert.

What do I know???

No Al, I'm not an expert just not a post whore.

The Big Al
08-26-2006, 12:05 AM
No Al, I'm not an expert just not a post whore.

I not one, a Whore gets paid!

73maverickjet
08-26-2006, 11:10 PM
Thanks for the replys? Just for the record I am running nicson aluminum wet threw hull manifolds, with stock intake and 750 rochester carb. Engine seems to be mostly stock. (for now) It does have big valve Ka heads with some big exhaust ports. Which past owner said he could never find gaskets that where big enough for the ports. Might have a little cam. Beside that the past owner and I dont know what else the engine has in it. It Spins a AA @ 4000-4200 rpm and I can get 60 with no weight. Seems to run pretty good. Hope this helps some of you who now what your talking about.... Thanx ;):D

OldSleekOlds
08-27-2006, 07:23 AM
The Berkley Pump Manual indicates that you are making 250 - 275 hp. You exhaust system is comparable to mine. I would recommend an Edelbrock Performer intake. The exhaust system restricts the flow through the engine and limits the effectives of the intake side of the engine. I also think a larger carb would help get more power for you.

It would seem that switching to an "A" impeller would allow the engine to make more power at higher rpm. HOWEVER, without knowing if any "oiling mods" have been done to the engine, the rpm range you have now is the safest place to be. A Performer intake and bigger carb should get more rpm. with the impeller you have.

The speed you're getting may be just right. You didn't mention anything about the boat (hull size, type, weight, etc.).

bdhr
08-27-2006, 08:48 PM
well now,, seems everyone's all excited over the big torque'ster.

i may be deficient in my current berkly problem, but i have vast

455 expierience,,and forcing that momma past 5000 r's is a waste of time.

i don't care what anyone has done to it downstairs. make it breath in and

out. if the out isn't better that the in,,more waste of time.

that's my humble input... now.. does anyone have gobs of knowledge for my dilema??
todd

73maverickjet
08-27-2006, 11:16 PM
Thanks old sleek olds. The hull is 19ft and its a 73 wriedt maverick. Dont know the weight, but it would seem to be in the middle class for this style. Its Low, wide and looks like most of the other boats on here that dont have winshields. Like your picture. Working on posting pics but need new scanner:( I thought it was making at least 300 hp but I guess maybe not:( Must have stock cam. It does have stock oil pan:( But if things are goin ok this winter she be getting pulled apart. Big pan, restricted push rods, cam, and a few other mods for safe 5000 rpm running. I would like to get 70 out of it:D The last owner didnt remember what impellar he put in. He is getting kinda old. But the AA is what hiperformance recommends and that is what he did remember. He bought it there and said he got the one they recommended. So im pretty sure it is AA and when I called hiper they said that sounded right also. Any other tips or tricks would also be great. I also have short drop snoot place diverter and fin on pump and it also looks like different loader grate installed:) Thanks again:)

OldSleekOlds
08-27-2006, 11:41 PM
I think you're right on track with your plan.

I've tinkered with a few jet boats and sometimes a good idea turns out to be a bad idea. For example, I had a 72 Sidewinder (18' - 455 Olds - Berkley Pump) and started right out by spinning a bearing. After fixing the motor, replacing the floor and transom (dry rot), I was sure good times were just around the corner. I bought a new Place Diverter and Droop Snoot. As soon as the parts arrived, I installed them and went boating. About a year later I wondered about the Droop Snoot. I started hearing that all boats didn't necessarily like them. I took the Droop off. WOW!! What a difference. The boat was faster, felt better to drive, what a lesson. The Place Diverter was a great improvement. The Droop was not.

The big lesson was one I learned many years ago (and forgot). Change ONE thing at a time so that you know which changes help and which changes hurt performance.

Good Luck :)

OldSleekOlds
08-27-2006, 11:43 PM
well now,, seems everyone's all excited over the big torque'ster.

i may be deficient in my current berkly problem, but i have vast

455 expierience,,and forcing that momma past 5000 r's is a waste of time.

i don't care what anyone has done to it downstairs. make it breath in and

out. if the out isn't better that the in,,more waste of time.

that's my humble input... now.. does anyone have gobs of knowledge for my dilema??
todd

I missed it. What is your dilema?

73maverickjet
08-28-2006, 08:23 PM
Thanks oldsleekolds. Well my dilema was what intake to replace my stock one with but it looks like a few people got off track. Basically I just got this boat mid summer and was looking to do a few smaller cheaper upgrades for more speed:cool: Like I wrote, the past owner didnt know much about the engine. He did put the snoot, diverter, and fin on though. And rebuild the pump. But after a few weeks on forums looks like I have a all stock motor:( But atleast it seems I got a good set of heads, which leads me to another ? Ever have any problems finding big enough gaskets to fit the exhaust ports. Seems to be a problem the last owner said he had. Couldnt find any big enough. They are stock style Ka which are suppose to be good heads. It does seem to be stock and have a stock oiling system.:( Havent got to take apart yet. But it does run 30-40 lbs idle and 50-60 at wot which is only at 4200 rpm max. On that note what is your recommendation for cam and other mods for high power @ 5000 rpm max jet engine for this boat when its rebuild time, and I would like to get some over the transom bad boys some day If I dont put bbc in it. With that what power increase could I exspect when replacing stock carb and intake? Would it be worth it when it is stock or what for rebuild and go with bigger and better componets. Sorry for all the questions but you seem to have exsperiance with 455 jets;) Thanks for looking and repling to my ???s Thanks again:D

OldSleekOlds
08-29-2006, 10:35 PM
As for your exhaust gasket problem, it's a new one for me. Never heard of that problem before. As far as I know, just about everybody running "log type" exhaust manifolds on a 455 in a boat has exhaust leak problems. About a month ago, a guy told me that "CAT" (folks who make bulldozers) have an exhaust sealer the works on an Olds. He said it's a paste that you use in place of a gasket. He said he used it and has zero leaks. He also said the stuff is $$$$. I have Edelbrock heads....not wanna screw them up. I've tried about every kind of gasket, including solid copper. The high temp silicone stuff worked better than them all. That's what I use.

I have no idea what you could expect with an intake and carb upgrade. I will say that if you include an exhaust system change to OT headers system, you will have a very significant improvement in performance.

Here's my motor:
455 .....030 over = 462
Balanced rotating assy
Forged pistons 10.25:1
Edelbrock heads
Harlandsharp rockers
Performer intake
Holly 930 cfm Marine carb
10 qt. oil pan
Restrictors including push rods
Outside oil returns from rear of heads to pan
MSD ignition w/billet dist

Hardin log exhaust system really kills it.

On the Dyno w/Victor intake (lost 8 hp)
http://files.triton.net/old1/dyno_victor.jpg

Here's the cam I ended up with
http://files.triton.net/old1/final_cam1.jpg

And the final Dyno sheet
http://files.triton.net/old1/455_final.jpg

I am sure that a good set of headers and the Victor intake would get me at least 50 more hp.

That's about it.

The Big Al
08-29-2006, 11:08 PM
<TABLE id=table1 cellSpacing=0 cellPadding=5 width="100%" border=0><TBODY><TR><TD><TABLE id=table2 cellSpacing=0 cellPadding=5 width="100%" border=0><TBODY><TR><TD vAlign=top width=250><TABLE cellSpacing=0 cellPadding=0 border=0><TBODY><TR><TD style="BORDER-RIGHT: #cccccc 1px solid; PADDING-RIGHT: 5px; PADDING-LEFT: 5px; PADDING-BOTTOM: 5px; BORDER-LEFT: #cccccc 1px solid; PADDING-TOP: 5px" vAlign=top>http://www.permatex.com/images/DisplayImage.asp?210|/images/ProductPhotos/29132.jpg</TD></TR><TR><TD vAlign=top><TABLE cellSpacing=0 cellPadding=0 width="100%" border=0><TBODY><TR><TD vAlign=top bgColor=#cccccc>http://www.permatex.com/images/spacer.gif</TD><TD vAlign=top width=10>http://www.permatex.com/images/img_botright.gif</TD></TR></TBODY></TABLE></TD></TR></TBODY></TABLE></TD><TD vAlign=top width="100%">MotoSealŪ 1 Ultimate Gasket Maker Grey
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Suggested Applications: Transmission case halves, cylinder head top covers, center & end covers (transmissions), crank case halves, cam covers, exhaust manifold seals, timing chain cases, side covers, clutch housings


</TD></TR></TBODY></TABLE></TD></TR><TR><TD><TABLE class=product-table cellSpacing=2 cellPadding=4 width="100%"><TBODY><TR class=table-head><TD vAlign=top align=middle width=78>Item #</TD><TD vAlign=top align=middle width=220>Container Size</TD><TD vAlign=top align=middle width=66>Pack</TD><TD vAlign=top align=middle width=87>Part #</TD><TD vAlign=top align=middle width=62>MSDS</TD><TD vAlign=top align=middle width=62>TDS</TD></TR><TR class=table-row><TD vAlign=top align=middle>29132</TD><TD vAlign=top align=middle>2.7 oz. tube, carded</TD><TD vAlign=top align=middle>6</TD><TD vAlign=top align=middle>29132</TD></TR></TBODY></TABLE>

They call it at case and Volvo, Motoseal,, same name from Permatex, they are the maker for the manufacture.

</TD></TR></TBODY></TABLE>

73maverickjet
08-29-2006, 11:40 PM
Thanks oldsleekolds and big al for the info. I'll have to try the gasket maker stuff because it does have the exhaust leak also. But like I was saying maybe the exhaust ports are ported because the last owner had to cut gaskets to make them fit head ports. I'll have to take a close look at the ports when I try the gasket sealant. Tried high temp permatex but it only lasted short time. But I do enjoy wrenching and tinkering. (Most of the time!) So I'll also have to try taking the drop off and see what happens, and the fin which someone said would make for more speed? I sure have cought the jet boat bug already, if I only had $$$$$$$$$. Oh well in time she'll be bad a*#, for now she still bad and makes 250ft rooster which everyone loves and is awsome. Thanks again guys this forum has been great and informative.:D Till next time.:cool:

J Lamb
09-09-2006, 07:08 PM
In response to your original question. I would go with the Edlbrock or if you can find one a Holley street dominator but they stopped making them years ago. I don't believe the HEI will clear the Offy intake. Keep the carb aorund 750 cfm, any more is just overkill. It ain't a BB chevy, it doesn't need a lot of rpms, I would stay under 5400. Turn it up more and it will surely die. Good luck on sealing exhaust manifolds for long on an Olds. There has to be a trick, I just never knew it when I had mine.

fatboy0054
09-14-2006, 10:30 AM
The Olds Man Is Rite ! Ported Elenbrock Preformer ! If You Going To Try To Run Over 5000 You Are Trying To Hard ! The Pump Should Keep You Under 5500 , If Not ,the Clearence On Your Wear Ring Should Be Check And Hope You Got A Good Oil Return To Your Pan And A Ten Quart Pan To Put It In ! They Dont Like Them Rpms For Very Long ! I Had Five Olds Motors And Change To 500 Cadillacs WITH OLDS RODS !Got One In My 21 Footer One In My Air Boat ! And One In My Boat Puller ! Nothing Wrong With The Olds Just My Deal !I HEAR YALL TALKING ABOUT BBC CRATE MOTORS THEY SUCK ! BUILD IT YOURSELF !THEY DONT COME CLOSE TO OLDS AND CAD AT UNDER 5000 !SEEN ELEVEN BLOWN FIRST SIX MONTHS ! YOU NEED WALLET FOR OVER 5000 RPMS !MR OLDS -GOOD SET UP WISH YOU WOOD THROW AWAY THEM LOGS AWAY BUT I KNOW ! SEEMS LIKE YALL ARE TRYING THE RITE WAY ! COOL DEAL !THANKS