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apollo74
05-15-2002, 10:47 PM
hi guys. i have a 18' apollo jet with 455 olds and berk JC with "A" impeller all oem pac-jet. runs 4900 rpm at 58 mph. just installed a top loader grate and manual place diverter, but haven't run yet due to weather here in MI. i'm thinking of upgrading engine with intake change( performer or torker??) and cam change(any suggestions?), also have some aluminum nicson logs(any better than cast iron stockers?). i have already converted ignition to electronic with petronix and msd and have timing at 35 total all in at 3000 rpm. would these changes get me into the 70's? what are the thoughts on rudder with the place diverter, any loss of mph?? any other ideas from the experts? would a "AA" impeller be better? also need new speedo, any body make a good one? whats the best gps to get for the least amount of $$ ? thanks for any help, i've been reading alot for a month or so, great board!!

hack job
05-16-2002, 08:00 AM
Originally posted by apollo74:
hi guys. i have a 18' apollo jet with 455 olds and berk JC with "A" impeller all oem pac-jet. runs 4900 rpm at 58 mph. just installed a top loader grate and manual place diverter, but haven't run yet due to weather here in MI. i'm thinking of upgrading engine with intake change( performer or torker??) and cam change(any suggestions?), also have some aluminum nicson logs(any better than cast iron stockers?). i have already converted ignition to electronic with petronix and msd and have timing at 35 total all in at 3000 rpm. would these changes get me into the 70's? what are the thoughts on rudder with the place diverter, any loss of mph?? any other ideas from the experts? would a "AA" impeller be better? also need new speedo, any body make a good one? whats the best gps to get for the least amount of $$ ? thanks for any help, i've been reading alot for a month or so, great board!!
so many ? well i wouldnt run the troker manifold they are crap if your going to run that kind it least get the performer rpm its bettr and broder power range, most speedo are inacurate . so dont go there spend your money on a gps the small hand held ones are aobut 100 bucks at best buy or something like that.i really dont know that changeing the intake would get you up there maybe 65 with the place and the intake but wouldnt hold my breath ! good luck and watch out for that 455 the parts are getting hard to find.
see you on the water!
Tyson www.plumbersassracing.com (http://www.plumbersassracing.com)
oh and welcome to the board!
[This message has been edited by hack job (edited May 16, 2002).]

apollo74
05-17-2002, 12:02 AM
thanks hack job-trying to keep stock internals-excellent compression and oil pressure` with loader, diverter, new intake, new cam, and logs instead of oem cast manifolds would i lose top end going to "AA" impeller?

hack job
05-17-2002, 11:58 AM
well thats good to hear , as fro the aa impellor you might drop some rpm and keep the same speed or a little faster, if the motor has the balls to pull it. its tough to guess if you dont have the torque cruve and what not. or a dyno sheet. but sounds like you got a plan and thats great thing a lot of people just throw cash in to there boats and have no plan. ( up untill like three weeks ago i was that way http://free.***boat.net/ubb/wink.gif )
what kind of cam are you going to run? i wouldmake sure it will work with your stock vavle train ( lift and what not). good luck and get a gps on ebay they are pretty cheep!
oh one more thing what type of oem manifolds are you talking about. if they are the mercrusier i would think that they would be better than the logs. my logic is that the exhuast exits are larger on the mercrusier ones!
email me a pic and ill let you know what i think or post a pic.
Tyson www.plumbersassracing.com (http://www.plumbersassracing.com)
[This message has been edited by hack job (edited May 17, 2002).]

apollo74
05-17-2002, 06:46 PM
Originally posted by hack job:
well thats good to hear , as fro the aa impellor you might drop some rpm and keep the same speed or a little faster, if the motor has the balls to pull it. its tough to guess if you dont have the torque cruve and what not. or a dyno sheet. but sounds like you got a plan and thats great thing a lot of people just throw cash in to there boats and have no plan. ( up untill like three weeks ago i was that way http://free.***boat.net/ubb/wink.gif )
what kind of cam are you going to run? i wouldmake sure it will work with your stock vavle train ( lift and what not). good luck and get a gps on ebay they are pretty cheep!
oh one more thing what type of oem manifolds are you talking about. if they are the mercrusier i would think that they would be better than the logs. my logic is that the exhuast exits are larger on the mercrusier ones!
email me a pic and ill let you know what i think or post a pic.
Tyson www.plumbersassracing.com (http://www.plumbersassracing.com)
[This message has been edited by hack job (edited May 17, 2002).]
the cam i plan to run is either a mondello jm 22-25-10 (duration is 230@.050 and lift is .512) or the olds w-30 cam(duration is 244@.050 and lift is .474) both 110 lobe seperation. i'll upgrade lifters pushrods and rockers and increase oil capacity with new oil pan. the exhaust is cast iron square not sure who made them, but the weight savings alone may justify going to the logs. i'll email you a pic of them this weekend as well as post more accurate speed as i got a gps today. thanks, hack job for your help.
[This message has been edited by apollo74 (edited May 17, 2002).]

Tbolt
05-17-2002, 06:57 PM
you might want to try an airgap from edelbrock and dont waste the money on a AA until you know how it responds with your new mods. do you have a deep oil pan? if not find one or fabricate one out of the old pan the more oil the better. stock pan 5qrts. 1 in the heads 1 in the valley 1 in the filter 1 in the engine(bearings,cam, lifters) it's self that leaves 1 in the pan. NOT GOOD!! the more oil in reserve the better cornering hole shots you know. good luck

squirt
05-17-2002, 07:22 PM
I'm not an Olds guy but have read enough post to know that the Olds has some oilling problems. They are a good motor for your boat but they do retain alot of oil above the heads. If you have a stock pan and don't plan on doing the mods, oil restrictors, restricted push rods and head to pan oil return lines , just keep an eye out on the pressure gauge and if it drops, back out of it. During Long cruising above 3500 rpm your motor will have a tendency to pump your pan dry and leave the oil up in the heads. All that being said there are a ton of 455's in jets living a happy life and ripping up the water! Have Fun! ROOSTERS AWAY

TE081
05-17-2002, 07:48 PM
dont rule out a b impeller! Originally posted by apollo74:
hi guys. i have a 18' apollo jet with 455 olds and berk JC with "A" impeller all oem pac-jet. runs 4900 rpm at 58 mph. just installed a top loader grate and manual place diverter, but haven't run yet due to weather here in MI. i'm thinking of upgrading engine with intake change( performer or torker??) and cam change(any suggestions?), also have some aluminum nicson logs(any better than cast iron stockers?). i have already converted ignition to electronic with petronix and msd and have timing at 35 total all in at 3000 rpm. would these changes get me into the 70's? what are the thoughts on rudder with the place diverter, any loss of mph?? any other ideas from the experts? would a "AA" impeller be better? also need new speedo, any body make a good one? whats the best gps to get for the least amount of $$ ? thanks for any help, i've been reading alot for a month or so, great board!!
[This message has been edited by TE081 (edited May 17, 2002).]

apollo74
05-17-2002, 07:48 PM
Originally posted by squirt:
I'm not an Olds guy but have read enough post to know that the Olds has some oilling problems. They are a good motor for your boat but they do retain alot of oil above the heads. If you have a stock pan and don't plan on doing the mods, oil restrictors, restricted push rods and head to pan oil return lines , just keep an eye out on the pressure gauge and if it drops, back out of it. During Long cruising above 3500 rpm your motor will have a tendency to pump your pan dry and leave the oil up in the heads. All that being said there are a ton of 455's in jets living a happy life and ripping up the water! Have Fun! ROOSTERS AWAY
definately planning on increasing the size of oil pan and adding the restricted pushrods, however i don't agree with restricting oil to the bearings as that is like treating the symptom instead of the sickness. from what i have researched is the olds likes to pump alot of oil to the heads and its slow to return, so restricting the flow to the heads via the pushrods makes sense, but the other restrictors became popular before the pushrods where available. so far in 100% stock setup the oil pressure has not waivered below 50 psi during extended 3500 rpm cruising or 30-60 sec blasts at 5000 rpm, but better safe than sorry. i'm also running mobil 1 and suspect that by its nature may drain back a little quicker. i'm hoping i end up with enough power to run the AA because i'd love to keep the rpm's as low as possible. i'll get some new data with the gps and the loader and diverter upgrade and keep you guys posted. thanks for all your help! damn this is alot of FUN!!!

apollo74
05-17-2002, 07:58 PM
Originally posted by Tbolt:
you might want to try an airgap from edelbrock and dont waste the money on a AA until you know how it responds with your new mods. do you have a deep oil pan? if not find one or fabricate one out of the old pan the more oil the better. stock pan 5qrts. 1 in the heads 1 in the valley 1 in the filter 1 in the engine(bearings,cam, lifters) it's self that leaves 1 in the pan. NOT GOOD!! the more oil in reserve the better cornering hole shots you know. good luck
wasn't aware that they made an air gap for the olds, but got a good deal on a performer from one of the guys on the board here as well as larger pan and some valve covers. got a " out of the box, lost the instructions deal on a new Garmin gps for $60 at best today, so pretty happy with that-came home and downloaded a manual off Garmin's website for free and we are in like flynn-yipee! thanks for the tip-we are going to have to watch it until i can pull the motor to install the pan. how many HP to turn a AA 4500 to 4900 rpm? if my setup ends up turning the A i've got over 5000 and the punp is tight, then would i want to go to a AA?

Old Guy
05-17-2002, 08:00 PM
Welcome apollo74. I have been running a 455 olds for about 10 years. Learned lots the hard way. I would recommend the AA impeller. I have been running a AA impeller at about 4800 rpm pushing a '74 18' Sidewinder in the high 70's mph. It takes close to 500 hp to do that. You either got a strong motor or a worn pump. If you're not sure about the pump, I would stay with an A impeller. The olds has a habit of pumping all the oil up to the top of the heads if you rev it very high. If you search this forum for "olds", you will find lots of comments about "oil problems". The motor doesn't have "oil problems". It just wasn't designed to run at high rpm. You can make it plenty strong and stay under 5000 rpm. The Olds Guru seems to be Mondello. If you're willing to spend the money, they can help you get your olds to 6000+ rpm. Personally, I wouldn't go there (6000). I have spent quite a bit with Mondello and I can recommend them as the best source I have heard of for olds info. They have a tech manual that is very good. Where in Michigan are you? I also live in MI. Nice weather huh!
old

apollo74
05-17-2002, 08:09 PM
Originally posted by TE081:
dont rule out a b impeller!
[This message has been edited by TE081 (edited May 17, 2002).]
hey te081 whats your theory behind a B impellor? wouldn't that go against the theory of keeping the rpms on an olds below 5000. just curious. thanks!

apollo74
05-17-2002, 08:20 PM
Originally posted by Old Guy:
Welcome apollo74. I have been running a 455 olds for about 10 years. Learned lots the hard way. I would recommend the AA impeller. I have been running a AA impeller at about 4800 rpm pushing a '74 18' Sidewinder in the high 70's mph. It takes close to 500 hp to do that. You either got a strong motor or a worn pump. If you're not sure about the pump, I would stay with an A impeller. The olds has a habit of pumping all the oil up to the top of the heads if you rev it very high. If you search this forum for "olds", you will find lots of comments about "oil problems". The motor doesn't have "oil problems". It just wasn't designed to run at high rpm. You can make it plenty strong and stay under 5000 rpm. The Olds Guru seems to be Mondello. If you're willing to spend the money, they can help you get your olds to 6000+ rpm. Personally, I wouldn't go there (6000). I have spent quite a bit with Mondello and I can recommend them as the best source I have heard of for olds info. They have a tech manual that is very good. Where in Michigan are you? I also live in MI. Nice weather huh!
old
hey old guy,
i live outside of grand rapids, how about you? the weather here has not exactly been conducive to boating thats for sure. more like march than may. if it doesn't change pretty quick, i may have to pull the motor and pump and go thru the whole thing!( not till fall-too much fun to be had this summer, when it gets here!) your sidewinder should be pretty close to my apollo as far as weight, so what did you do to your motor to get the 500 ponies? i agree that going much over 5000rpm is both costly and risky, so i don't want to go there. i'll get some gps readings this weekend, but i'm starting to suspect the pump is loose although it seems real fast. do you have a diverter on yours? are you running any type of loader grate? i'm trying to figure out where i'm at so when i have the pump done i'll know what impellor to use, but this seems to be much less than an exacting science! any ideas would be great! thanks
[This message has been edited by apollo74 (edited May 17, 2002).]
[This message has been edited by apollo74 (edited May 17, 2002).]

Old Guy
05-17-2002, 08:37 PM
I'm about 20 mi south of Grand Rapids. To get the ponies I got from Mondello....
Rotating assy
Mondello/Edelbrock heads
Edelbrock intake
10 qt. oil pan
good starter
Holley 850 dble pmpr carb
HDM ignition
You might not want to go that far. If you do, I can give you all the details.
No loader grate, just a sharp edge stainless one I made to help with weeds.
Right now I'm puting the olds in a 20' Sleek Craft tunnel I got last fall.
Glad to help any way I can.
old

1HOTGMCJET
05-18-2002, 07:42 AM
Michigander here too, fellas - (NW of Detroit) - if I ever get my boat back together (J/K - I WILL), we're gonna have to have a little "fun run" during our 2 weeks of summer - lol http://free.***boat.net/ubb/tongue.gif

apollo74
05-18-2002, 07:56 AM
Originally posted by 1HOTGMCJET:
Michigander here too, fellas - (NW of Detroit) - if I ever get my boat back together (J/K - I WILL), we're gonna have to have a little "fun run" during our 2 weeks of summer - lol http://free.***boat.net/ubb/tongue.gif
since when did they increase our summer from 1 to 2 whole weeks!?!? j/k . your right, us michigan guys need to have a get together some weekend-email me if your interested and i'd be happy to organize. i'm sure we'll have 1 sunny weekend(maybe?).

hack job
05-18-2002, 07:56 AM
Originally posted by apollo74:
wasn't aware that they made an air gap for the olds, but got a good deal on a performer from one of the guys on the board here as well as larger pan and some valve covers. got a " out of the box, lost the instructions deal on a new Garmin gps for $60 at best today, so pretty happy with that-came home and downloaded a manual off Garmin's website for free and we are in like flynn-yipee! thanks for the tip-we are going to have to watch it until i can pull the motor to install the pan. how many HP to turn a AA 4500 to 4900 rpm? if my setup ends up turning the A i've got over 5000 and the punp is tight, then would i want to go to a AA?
well i know that edlebrock dosent make the air gap for the olds motors the only motors its made for is chevy and small block ford for now any way. it is tought to make that with the runner going to the out side it would become a victor or some thing like that. good luck with all of that! and once again welcome to the fun ( spending loads of cash on a boat!) have fun
Tyson www.plumbersassracing.com (http://www.plumbersassracing.com)

bobz
05-18-2002, 04:29 PM
the oil retrictors keep oil in the mains were you need the oil. it restricts the oil in the top of the motor, they are 20 bucks i think well worth the money if you have adjustable valve train go with the 512 lift and advance the cam 4 degrees it will lower you power curve by 500 rpm. thats 50 free horsepower at the rpm you need it.

apollo74
05-19-2002, 07:00 AM
Originally posted by bobz:
the oil retrictors keep oil in the mains were you need the oil. it restricts the oil in the top of the motor, they are 20 bucks i think well worth the money if you have adjustable valve train go with the 512 lift and advance the cam 4 degrees it will lower you power curve by 500 rpm. thats 50 free horsepower at the rpm you need it.
i was trying to avoid pulling down a perfectly good motor, so i was going to install the restricted pushrods first. i also came across a device called masterlube, that is designed to be an accumulator as well as a pre-luber for the engine. i thought this might be a good safety until i pull the motor and do it right. has anybody ever used one of these? they make them for marine applications. pics of my boat on www.teshio.com (http://www.teshio.com) . thanks for all your help guys!

Hallett19
05-19-2002, 10:07 AM
EVER HEARD THE OLD ADAGE "IF IT AINT BROKE, DON'T FIX IT!!!" Shit man, if you have a stock Olds that still runs good, don't **** with it, and when it goes, lay into that thing, but untill then, enjoy boating. If my stock motor hadnt gone bad last year, I would have never done shit to it, the minute you start screwing with these things, you start running into problems. Now a oil pan, I would recomend for that boat, but don't start tearing apart a motor that runs just fine, please.

Q-ball
05-19-2002, 12:30 PM
Good point hallet, what a pain in the ass my project has been, not to mention if I put it in the water this year and it's not as reliable as last year , momma will never let me hear the end of it!!!

apollo74
05-19-2002, 02:56 PM
Originally posted by Hallett19:
EVER HEARD THE OLD ADAGE "IF IT AINT BROKE, DON'T FIX IT!!!" Shit man, if you have a stock Olds that still runs good, don't **** with it, and when it goes, lay into that thing, but untill then, enjoy boating. If my stock motor hadnt gone bad last year, I would have never done shit to it, the minute you start screwing with these things, you start running into problems. Now a oil pan, I would recomend for that boat, but don't start tearing apart a motor that runs just fine, please.
that was exactly my point, i was trying to get as much speed as i could without messing with the motor. it runs real good and fire s right up and the oil pressures holds good thru all rpm's including WOT. i thought the accumulater might be a good safety valve for the olds oiling issues. also what do you think about the intake and cam change- bad idea? maybe i should just have the pump gone thru and be happy with what i got. finally gps'd her today- 57 mph at 5100 rpm. looks to me that the pump could use some attention- what do you guys think?

wsm9808
05-19-2002, 06:44 PM
Mine runs just a tad over 70 at 5200 rpm with an A impeller, but with 5 people and gear(beer) on board it drops to the low 60s at 5200. So the weight and wetted area on the hull will make a big differance when compairing speed on differant boats.

apollo74
05-19-2002, 07:11 PM
Originally posted by wsm9808:
Mine runs just a tad over 70 at 5200 rpm with an A impeller, but with 5 people and gear(beer) on board it drops to the low 60s at 5200. So the weight and wetted area on the hull will make a big differance when compairing speed on differant boats.
mine was full of gas(bow tank-20 gal) and 500 lbs. of riders/gear. best speed was 2 notches from full up on manual plce diverter, any more and speed fell off. do i not have enough HP to keep the front up at speed or just the pump throwing to much water in the air. any body know what the power curve of the stock 330hp olds 455(pac jet-2)? any ideas?

cncer691
05-19-2002, 07:27 PM
Yeah apollo74, I thuink your pump might need to be gone through. I get about 4100 rpm @ 59 mph w/ my 12JC running an A impeller. I think my motor was pulled from a Delta 88. I did the usual bolt-ons just to make it reliable not so automobile like, but have yet to see any performance gains.

apollo74
05-19-2002, 08:26 PM
Originally posted by cncer691:
Yeah apollo74, I thuink your pump might need to be gone through. I get about 4100 rpm @ 59 mph w/ my 12JC running an A impeller. I think my motor was pulled from a Delta 88. I did the usual bolt-ons just to make it reliable not so automobile like, but have yet to see any performance gains.
hey cncer691
what kind of boat do you have that olds pushing? does your motor max out at 4100?
who did your pump? basic rebuild or blueprint?

cncer691
05-20-2002, 02:25 AM
Apollo, I have a 16 foot Tahiti. http://www.teshio.com/JetBoat/tahiti.htm.
I am using a marine Tach for all typed of motors, so I don't know how accurate, but according to it tops out at about 4100 rpm. I had Don's Pump Service rebuild my pump, a basic rebuild w/ cavitation reducer. He wantee to go AA, but since my motor isn't that strong, I felt the AA would put me well below peak HP. I haven't put it in the boat yet. I'll know by Saturday.

cncer691
05-20-2002, 02:27 AM
http://www.teshio.com/JetBoat/tahiti.htm
It is the one on top.

apollo74
05-20-2002, 06:52 AM
Originally posted by cncer691:
Apollo, I have a 16 foot Tahiti. http://www.teshio.com/JetBoat/tahiti.htm.
I am using a marine Tach for all typed of motors, so I don't know how accurate, but according to it tops out at about 4100 rpm. I had Don's Pump Service rebuild my pump, a basic rebuild w/ cavitation reducer. He wantee to go AA, but since my motor isn't that strong, I felt the AA would put me well below peak HP. I haven't put it in the boat yet. I'll know by Saturday.
well i can see that you you are definately lighter than my boat, so that would explain the lower rpm at about the same speed. did you say your pump is rebuilt with cavitation reducer at that rpm and speed or that you just had that done and haven't tested it yet? was the speed gps'd or speedo? thanks for the input.
[This message has been edited by apollo74 (edited May 20, 2002).]

wsm9808
05-20-2002, 11:09 AM
I'm not trying to start anything here, but a Berkley A impeller in a pump at stock specs should pull 4600 to 4700 rpms with 330 hp, it should not matter if the boat weighs 2000# or 4000# or is tied up to the dock. A lighter boat will usually have a higher top speed due to less drag

cncer691
05-20-2002, 11:37 AM
I don't know if my tach reads low, or if I just have a weak motor. It was pulled straight from about a 1974 car. All I did was put on a Performer intake and a holley 850, and upgraded the ignition. About the cavitation reducer...I haven't tested it yet. I never had a cavitation problem before, but either Don is a good salesman, or i am an easy sale, because I was like "sure!"

apollo74
05-20-2002, 04:53 PM
Originally posted by wsm9808:
I'm not trying to start anything here, but a Berkley A impeller in a pump at stock specs should pull 4600 to 4700 rpms with 330 hp, it should not matter if the boat weighs 2000# or 4000# or is tied up to the dock. A lighter boat will usually have a higher top speed due to less drag
ok, so what your saying is that assuming a tight pump the rpm basically will tell you the horsepower of the engine irrelevant of weight or size of boat? so if one knows the horsepower he has or is planning on modding to, then he can select impellor size from that? then how do you explain all the confusion there seems to be over which impeller to run? if its that simple why not just pull motor, get it dynoed and order the appropriate impellor? or is all the guessing because we are trying to avoid dynoing the motor? thanks for all the help with my stupid questions!

wsm9808
05-20-2002, 08:07 PM
From the imformation I have been able to gather, if you have your dyno numbers you can use the charts to match your impeller and get it right for your power curve. But, again, that is a stock pump set at original specs. That all goes out the window when you alter clearances, change brands of impeller or modify the impeller and start tinkering with you engine combo and changing the power band. And all pump/engine combos where not originaly set up for top speed. Many came stock with bigger impellers to be able to cruise at a moderate speed with out turning the engine at high rpm.

apollo74
05-20-2002, 09:05 PM
Originally posted by wsm9808:
From the imformation I have been able to gather, if you have your dyno numbers you can use the charts to match your impeller and get it right for your power curve. But, again, that is a stock pump set at original specs. That all goes out the window when you alter clearances, change brands of impeller or modify the impeller and start tinkering with you engine combo and changing the power band. And all pump/engine combos where not originaly set up for top speed. Many came stock with bigger impellers to be able to cruise at a moderate speed with out turning the engine at high rpm.
good point- i guess if it was easy we wouldn't have anything to talk about. does any one publish gpm #'s on their pumps at a given rpm? so we could compare gpm at any given rpm for any impeller and then look at hp and rpm charts and pick our set-up from there? seems like that would be helpful.