Tahiti Restoration Project

[Coded-Dude]

Hello All,
This is my first post, so I'll tell you a little bit about myself:
Owner of a 78 Tahiti Jet Boat - 460 Ford, Berkeley Pump.
I bought this boat from a guy who had never previously used it. He bought it from a police auction - from what I understand it was left on the side of the highway(idiots).
Anywho, he needed the money and thus was selling it. I tried to haggle with the price, since the boat wouldn't even start, but was only successful in knocking a few
hundred off the $2k price tag. Took the boat home, yanked the carb off and put known good one on and what do you know......the damn thing fired right up. :D
(the guy apparently knew more about renting equipment than rebuilding carburetors)
After a little work, and a little more money the boat was sea-worthy.........Its been a blast to own, especially since I have spent little to no money on it at all. (except gas!!!!!!!)
This year, things are changing. The boat is getting restored.
I ripped out the seats, motor, and pump. Sanded the body down, which is basically ready for paint, and started "prettying" up the motor. So far, everything I've put on has
been asthetic: chrome valve covers, stainless steel oil pan, chrome breather, new wires/wiring harness, etc. In fact, the only things I plan to add to the boat that will
impact Performace are: Impeller(probably stainless steel), Intake Manifold(Edelbrock Performer RPM), Mallory Marine Distributor, Larger Fuel Pump(Summit Chrome),
and possibly a Place Diverter. I'll post some digital pics once I get them. I have a few hard copies I can scan/post as well.
Anywho, here is my concern/question to you.
The boat probably barely did 50 in its previous condition, and while I am adding some performance to the thing, I don't expect a lot from what I am doing this year
(15mph is an especially generous estimate). Next year will be the move to substantially more performance. My buddy is telling me I need to take my new
oil pan back, because its a stock street oil pan(much like the one I just replaced). There are no baffles, windage trays, or special pick-ups to speak of, but its been running
with this configuration since I have owned it.
So.......Should I take my NEW $50 stainless steel Oil Pan back to Tognotti's and order a $350 Oil Pan with a custom $75 Pick-Up?
Am I pushing my luck with what I am currently using, even though I have used this setup for the last 3-4 years(with a slightly less powerful configuration).
Your opinions on this matter will be greatly appreciated!
(I'll come back with some pics very soon)

[jetboat]

i'll offer the advice given to me,redoing the first 460 bbf motor sounds a lot like what you said,differernt man'fld,750 carb,blaster,wiring,new dist.STOCK oil pan with baffles,all nwe paint,seats,wiring etc.etc etc.the final speed run with gps!52mph.and never much more.the boat is a avenger 18' with also a jg stock pump. and now ride plate.now to the second boat,a 18 taylor also with a 460 but punched .30 over,ported,rpm man'fld,830 dbl pump.580 plus cam,rocker rollers,msd,ott rewarder headers,many additional engine mods,it almost 500hp.now has a diverter with extended ride plate,the est speed now is high 70's and next year nitrus.theres a lot of helpfull people on this suite,and some have become personal friends.we all have a common like,boats,rv's,atv's jet skis,and the wifes always find a mall to shop!welcome and ask away.

[Oldsquirt]

In fact, the only things I plan to add to the boat that will
impact Performace are: Impeller(probably stainless steel), Intake Manifold(Edelbrock Performer RPM), Mallory Marine Distributor, Larger Fuel Pump(Summit Chrome),
and possibly a Place Diverter. I'll post some digital pics once I get them. I have a few hard copies I can scan/post as well.
.....Next year will be the move to substantially more performance. My buddy is telling me I need to take my new
oil pan back, because its a stock street oil pan(much like the one I just replaced). There are no baffles, windage trays, or special pick-ups to speak of, but its been running
with this configuration since I have owned it.
Let me suggest a change in priorities.
First, the best bang for the buck will be a Diverter.
Second would be the manifold change.
Ignition upgrade would be third.
You don't need a "bigger" fuel pump, but if you are going to buy one, get a brand name not the chrome Summit "house" brand(unless you can confirm it is made by one of the "brand name" companies).
If you plan on a serious power upgrade in the near future, the Jet boat specific oil pan and pickup would carry over, but aren't really "needed" at this time. Plenty of jets running stock pans.
The stainless impeller is not a "performance upgrade". It will not provide increased performance by being stainless. Stainless is stronger and will hold up to much higher power levels or abuse (such as jumping wakes/waves, etc, which causes very high loads on the impeller when the pump goes dry and then reloads). This is why you see them in high-performance jets.
Hate to say it, but a 15 mph gain is probably wishful thinking with out a fairly big power increase or finding that the pump is worn out. BTW, was speed measured with GPS, radar or just the stock speedo?
One more thing.....What RPM were you turning at max boat speed?

[Coded-Dude]

Let me suggest a change in priorities.
First, the best bang for the buck will be a Diverter.
It's definitely planned, but not a high priority to get the boat back in the water.
Of course, once the is boat sea-worthy again, this should be a fairly painless install......
Second would be the manifold change.
Should arrive today!
*Next year may be tunnel ram with dual 750's*
Ignition upgrade would be third.
Well, I'm looking at the MSD "ready-to-go" Marine distributor with the built in Ignition Module
Or the Mallory Marine distributor(which would probably require an ignition box upgrade)
The Mallory has a black cap, which matches our Black/Chrome Engine scheme, other than that I am leaning towards the MSD "ready-to-go" dist.
You don't need a "bigger" fuel pump, but if you are going to buy one, get a brand name not the chrome Summit "house" brand(unless you can confirm it is made by one of the "brand name" companies).
Well, its too late for that.....although this was only a $40 purchase and is re-buildable.
Its also much better than the stock pump we had on there.
If you plan on a serious power upgrade in the near future, the Jet boat specific oil pan and pickup would carry over, but aren't really "needed" at this time. Plenty of jets running stock pans.
Thanks to both of you for your input on this subject! ;)
The stainless impeller is not a "performance upgrade". It will not provide increased performance by being stainless. Stainless is stronger and will hold up to much higher power levels or abuse (such as jumping wakes/waves, etc, which causes very high loads on the impeller when the pump goes dry and then reloads). This is why you see them in high-performance jets.
Correct.....this is also why I want to do this now:
The pump is out and going to be rebuilt, the old aluminum impeller is a little "rough."
Considering this, and the fact that I want to increase HP next year; I might as well do it now while the pump is out.
Although, I may just get a performance aluminum one this year, seeing as how the price difference is pretty drastic.
Hate to say it, but a 15 mph gain is probably wishful thinking with out a fairly big power increase or finding that the pump is worn out. BTW, was speed measured with GPS, radar or just the stock speedo?
Yeah, thats why I said especially generous, but even 5 mph would be a nice addition, for mostly aesthetical work. Speed was never measured, only a best guesstimate.
One more thing.....What RPM were you turning at max boat speed?
Lol, your might shake your head for this one but......the only working gauge I had was a mechanical oil pressure gauge. This boat was highly negelected(by its previous owners), and I only spent enough money to keep it running, but all that is about to change.

[Oldsquirt]

Save the money you would spend on the stainless impeller and put it towards the Place diverter. It is a far better investment at this point!!!!! You will likely see an increase in speed with the diverter as well as having the ability to trim for varying water conditions.When you get to the serious engine upgrade, THEN look into an impeller upgrade to match(mag-bronze or stainless). With a stock pump install(using the Berkeley transom adapter) an impeller swap takes about an hour.

[Jetaholic]

Sounds a lot like my 78 Marlin Project! lol Exept all but the speedo gauge worked.
The motor was a 455 Olds that was pulled straight out of a car and installed in this thing.
The pump intake was not set in correctly (was portruding the bottom by about 3/8" instead of being flush).
The pump was tired and had a rope stuck in it.
The carb was only a 650 spreadbore Holley and the ignition was a stock HEI distributor.
Had a bow gas tank, which increases drag at the front of the boat and makes it harder to lift off of the water if the thing had a diverter.
And the pump did not have a diverter on it.
Thru-transom exhaust
List of things that have been done to it:
Added a diverter
Self adjusting cooling system (water bypass pressure regulator valve and a thermostat)
Motor change from 455 Olds to a BBC 454
Motor has been marine built for 500HP
Eliminated thru-transom exhaust and will be installing Bassett OT Headers
Pump rebuild with all new internal components and the rope seal was changed to a neoprene seal
Added a Jet-A-Way to the pump
9qt marine oil pan
Holley 750DP marine carb
MSD Marine ignition w/ready-to-run distributor
Marine starter and alternator
Removed bow tank and installing saddle tanks
All new cables
All the sub floor and stringers were replaced, bottom was semi-blueprinted and cracks in deck were fixed, along with all new gelcoat
All new wiring, switches and gauges, including the addition of a GPS Speedometer
Hoping to see about 65mph out of this one.

[dumbandyoung]

my grandpa had a 76... it was passed down to me when i was 17 then i traded for an omega..
post some pics of your boat!
http://img528.imageshack.us/img528/9462/img0006bj9.jpg

[Coded-Dude]

@ Oldsquirt - Thanks, I wasn't sure how easy it was to replace the impeller, but you have persuaded me to wait.
As stated I have a few hard copy pics I will scan and post, but need to take some digital ones soon.
I may try and get some on here tommorrow though.
Thanks again for all the input thus far, its helped get me more excited about this project and cleared up some major concerns I was starting to have.

[jetboat]

on any jet boat the faster you want to go,the more youl spend.so get a budget for the go fast things and for the fancy things,then triple the go fast and if its not broke and can be redone nicely,leave it.at this point you have seen supper cool boats and read there mail,remember,its your first i think?we have been at this for a while .take your time and only get what you really need vs really want.o ya!i'am also from california (orange county,huntington beach).

[DBR]

Dude,
You need to put a supercharger on it, and it'll do 100mph easy. My does 90+ with just one carb on the 455 olds. Tahiti's are the badest race boats on the water.

[Coded-Dude]

lol......duly noted.
I was gonna post some pics today, but I didn't have a digital camera yesterday and the pics I took didn't turn out.
*well.....a few did, and I'll post em, but they are of the intakes*
Also had an issue with the scanner today, not wanting to email me my hard copy pics.
Suffice it to say the motor is complete(except for a distributor). I have decided on the MSD Marine Ready-To-Run one, but am hoping I can use MSD's NEW BLACK CAPS! (http://www.msdignition.com/2007/marine.html)
Now we have to finish the body work(the bottom), paint it, and rebuild the pump.
May is our projected finish month.

[raisinL]

Dude,
You need to put a supercharger on it, and it'll do 100mph easy. My does 90+ with just one carb on the 455 olds. Tahiti's are the badest race boats on the water.
Or just buy a ebay jet most of them will do 100 MPH.

[RiverRacer]

So.......Should I take my NEW $50 stainless steel Oil Pan back to Tognotti's and order a $350 Oil Pan with a custom $75 Pick-Up?
Am I pushing my luck with what I am currently using, even though I have used this setup for the last 3-4 years(with a slightly less powerful configuration).
Your opinions on this matter will be greatly appreciated!
YES! Opt for a Jet Boat specific Hi Capacity Pan, P/U and Windage Tray and a good Pump. Without a steady supply of lubricant, the rest of the engine will be dust. The more power it puts out, the quicker it will die without Oil Pressure and Volume.
By the way, my son's Tahiti is like yours. 1978 18' with a 460, JG Pump, Droop and Diverter. Good luck with your project. RR

[jetboat]

you have a 455 that runs 90!?''.what work has been done,bet theres alot of olds guysthat would like to know.

[Jetaholic]

you have a 455 that runs 90!?''.what work has been done,bet theres alot of olds guysthat would like to know.
I think that's the eBay speed.

[Coded-Dude]

Here's my baby:
Me at Lake Trinity.
http://img261.imageshack.us/img261/583/strinitykc5.jpg
My Brother giving the horns whilst we mob across the lake!
http://img267.imageshack.us/img267/7382/sbillwc7.jpg
The bow and dash.
http://img390.imageshack.us/img390/1108/sdashboardtj6.jpg
The empty insides.
http://img267.imageshack.us/img267/3253/sgutskg3.jpg
The transom
http://img267.imageshack.us/img267/2180/stransomvd4.jpg
Why one doesn't go fast when beaching his/her boat...
http://img264.imageshack.us/img264/1001/sparkingpx3.jpg
(i still give my buddy a hard time about that parking job)
The motor!
(these pics are not very good, but I'll come back with better ones soon)
http://img462.imageshack.us/img462/8130/stooshinyoi0.jpg
http://img364.imageshack.us/img364/1764/soilpankq7.jpg
Chrome fuel pump, chrome valve covers/breather, polished aluminum intake, stainless steel oil pan,
and polished aluminum mounting hardware. Not all of those parts are visible in these two pics(obviously), but you get the idea.