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djbartu
08-17-2005, 03:41 PM
Well, as summer nears it's end, dreams of next year's season already fill my head. This winter while my '86 tri star (351w/1:1 velvet drive) is put up for the winter, I plan to do a bit of an overhaul.

First of all, the interior will be reupholstered - any recommendations on the best types of vinyl to use? I haven't talked to the upholsterer yet as I wanted to get more info from all of you first. The carpet is in good shape, so that will stay.

Secondly, the boat itself looks OK, just a little dull in the finish but that should buff out. How would you shine it up?

Finally, and most importantly, performance upgrades - the boat already runs excellent, but who wouldn't want a few extra HP ... right? A few years ago I upgraded to Pertronix and that worked out great. Now I'm thinking new intake manifold and possibly carb. How about exhaust improvements? The boat has just over 540 hrs so I don't plan to pull the engine for a complete rebuild, just bolt on stuff. Reverse is gone in the tranny, so that will be rebuilt or replaced. What are the most "bang for the buck" performance improvements?

I've owned the boat for over 12 years and really never invested much into it. So I think it's time.

phecksel
08-18-2005, 11:33 AM
Well, as summer nears it's end, dreams of next year's season already fill my head. This winter while my '86 tri star (351w/1:1 velvet drive) is put up for the winter, I plan to do a bit of an overhaul.

First of all, the interior will be reupholstered - any recommendations on the best types of vinyl to use? I haven't talked to the upholsterer yet as I wanted to get more info from all of you first. The carpet is in good shape, so that will stay.

Secondly, the boat itself looks OK, just a little dull in the finish but that should buff out. How would you shine it up?

Finally, and most importantly, performance upgrades - the boat already runs excellent, but who wouldn't want a few extra HP ... right? A few years ago I upgraded to Pertronix and that worked out great. Now I'm thinking new intake manifold and possibly carb. How about exhaust improvements? The boat has just over 540 hrs so I don't plan to pull the engine for a complete rebuild, just bolt on stuff. Reverse is gone in the tranny, so that will be rebuilt or replaced. What are the most "bang for the buck" performance improvements?

I've owned the boat for over 12 years and really never invested much into it. So I think it's time.

Electronic ignition and CNC prop. Do you have the rocking fish killing stereo?

martini
08-18-2005, 12:05 PM
The intake upgrade is nice, a new carb wouldn't really help you unless yours needs to be rebuilt/replaced. One thing that you can do is install GT40 heads, that alone will wake that 351 up the most. The exhaust, unless you plan on spending lots of $$, is not really a viable option either. The exhaust on these boats is pretty open and unrestricted anyway. Heads are the way to go with these engines. They make the biggest difference.

djbartu
08-18-2005, 12:15 PM
Electronic ignition and CNC prop. Do you have the rocking fish killing stereo?

The stereo also needs to be replaced, but to tell you the truth, I never used it that much. Therefore, I would rather put the money into the "power to pull" department. I'll probably just get something basic for the amount I plan to use it.

erkoehler
08-18-2005, 12:22 PM
I got a sony head unit, and 4 speakers from Meijer CHEAP!!!! Check it out, I think it was under 250.00

MP3 head unit also.

east tx skier
08-18-2005, 03:24 PM
Get the CNC'd prop first. I did the intake upgrade and was very happy with it. But I already had the GT40 heads. Those three things would make a big difference in the low end torque.

Storm861triple
08-23-2005, 07:11 PM
What are the most "bang for the buck" performance improvements?

If you're doing the work yourself, a CAM is by far the biggest BFTB. For around $100, you can pick up 30+ horsepower.

If you're paying to have the work done, INTAKE is the best BFTB. Minimal labor, and about 10-15hp, and torque across the RPM band.

Heads are the biggest N/A BANG, period. The power is in the heads, and changing them with modern and efficient heads will give you the biggest results, hands down.

Read the specs, torque and power curves on the first three engines. And these are just little 302's....

http://www.airflowresearch.com/dyno/ford_dyno.htm

Ric
08-23-2005, 07:16 PM
steriods seem to be the enhancement of choice ;)

Workin' 4 Toys
08-23-2005, 09:32 PM
I would like to see a turbo or supercharger installed. Not necessarily because I recommend it, but mearly because I would like to see it done. I have yet to see anyone do it to a MC, and it would be awesome.

And there is always Nitrous. That's a cheap install. But the refilling the tanks and blown engine is not.

rektek
08-31-2005, 09:07 AM
"the boat already runs excellent"
prop, ulphostery, audio upgrade go for it, but if my boat was running excellent I wouldn't touch it ! and I'm auto technician by trade. belts, hoses, oil + filter, oil leaks sure... why tear into a good thing. save your money for rising fuel costs.

H20skeefreek
08-31-2005, 09:26 AM
I agree with rectek, you usually just end up messing something else up when you do unneccesary modifications, at least I do. Upgrade the prop and leave the other things alone (except for that tranny rebuild of course, can't imagine not having reverse)

BriEOD
08-31-2005, 10:00 AM
After conversing with JimN and VInce at Discount Inboard Marine at the begining of this season I replaced my intake manifold with an Edelbrock Performer 351 intake (199$ from DIM). It's a pretty easy install and I did it myself. You can unbolt the manifold and lift it straight up without having to remove the exhaust manifold/risers or the distributor. You'll have to unbolt the carb and change that over as well as your temp gauge, throttle cable, coil holder, PCV valve, fuel line and that's about it. Reassemble all the parts and pieces on the new one with new gaskets, set it down and tighten IAW the torque sequence. DIM will even fax/mail you the sequence and the PSI.

The only thing I would say that can be of a concern is that it's aluminum. So if you ski in salt/brackish water (I do not) that aluminum is going to wear down a lot quicker than the stock cast one.

:twocents:

east tx skier
08-31-2005, 10:08 AM
rektek has a good point there. Although I'm happy with my intake now, and even though I had it professionally installed, I dealth with unanticipated throttle cable mounting issues for a while before we got it figured out. In the end, it was worth it, but I missed having my boat around in April.

tph
08-31-2005, 10:30 AM
Isn't the Edelbrock Manifold taller? Does it fit under the stock engine cover ok?

BriEOD
08-31-2005, 10:32 AM
The intake isn't taller, you need a special mounting plate to go in the between the carburetor and manifold which in turn raises the carburetor a few inches. However, I haven't had any problems with the engine cover closing properly.

Storm861triple
08-31-2005, 12:39 PM
I'm auto technician by trade...why tear into a good thing. save your money for rising fuel costs.

I am too. So to answer your question, for the fun and satisfaction of it, and to get what everyone wants; MO-AH POWAH! (-That's my old Boston accent)

Also, modern heads w/a modern combustion chamber will improve fuel economy (though it will take a looooooooooong time to balance the initial mod-costs)

I want AFR heads on my motor. It runs perfect now too, but at 7000' elevation, I would surely appreciate more punch.

Storm861triple
08-31-2005, 01:32 PM
you need a special mounting plate to go in the between the carburetor and manifold
Why did you need a special spacer? It should bolt directly on to a Perfomer intake.

-Tom

east tx skier
08-31-2005, 02:07 PM
The mounting plate is for Holley to edelbrock. As far as I know, the edelbrock is taller than the stock. The mounting plate is not thick at all. But when I was done, my engine box was an inch or two off the carpet resting on the flame arrestor.

Should fit under a 1990 or older engine box fine. 91 and up, it's not going to fit (or it'll be real tight). I had to remove foam and go with a lower profile flame arrestor on my 93 (but my foam was thicker than stock).

Storm861triple
08-31-2005, 04:49 PM
The mounting plate is for Holley to edelbrock. As far as I know, the edelbrock is taller than the stock.

The Edelbrock intake should have the same square-bore flange as a Holley carb. That's why I'm confused here. I recently removed an Edelbrock carb from the Edelbrock Performer RPM intake on my Camaro, and bolted on a Holley 700 CFM 4150. It was the same.

I agree that a Performer intake is a bit taller than the stock iron intake.

east tx skier
08-31-2005, 04:57 PM
Thomas, the mechanic who installed it for me would agree with you. But since I'd already spent my $12, I decided I wanted it on there. Supposedly, it prevents vacuum leaks, but I'll agree they both look like squares to me. :)

Ski Dim's Adaptor Plate for 4160 to Edelbrock Performer Intake (http://skidim.com/prodinfo.asp?number=EDL-2732)

Back when the mechanic questioned the need for it, I called skidim and asked (don't know if it was Vince or not). Whomever I spoke to said it was necessary. My knowledge of this stuff doesn't put me in much of a position to argue about it. If you call them and get any more info on it, don't hesitate to post it.

Storm861triple
08-31-2005, 05:05 PM
...but I'll agree they both look like squares to me. :)
LOL! That was funny.

It looks like basically another "gasket" to me.

east tx skier
08-31-2005, 05:06 PM
Thomas, call 'em and post what you find out here. I may need to call and get my $12 back. :)

djbartu
09-01-2005, 09:37 AM
What about a phenolic spacer between the intake and carb? (Of course I'd have to check clearances first, but on the '86 there seems to be room for it?) If one is made for this Holly/Edelbrock application, would keeping the carb a little cooler be worth doing?

Storm861triple
09-01-2005, 11:57 AM
What about a phenolic spacer....would keeping the carb a little cooler be worth doing?
Only if you're having boiling issues, which is not common w/Holley 4150 or 4160 carbs. You could gain more power by fabbing up a "cold air intake" and a bonnet on the carb. That would be far more effective than insulating the carb from a ~160* intake, that's sitting in and sucking ~160* air.

Still even a CAI wouldn't help much. Probably not even noticable.

-Tom

east tx skier
09-01-2005, 12:00 PM
I think I had one of those spacers stock, too. About 1.5" tall, right?

east tx skier
09-01-2005, 12:01 PM
Well, I guess I can't see it in that picture afterall. Anyway, there's the low-profile flame arrestor if anyone wanted to see what that looked like.

Ought to be room for the whole shebang undere an 86 motorbox. They got lower in 91.

DooSPX
09-01-2005, 04:16 PM
east... what is the box with the control knob on it?? :confused:

6ballsisall
09-01-2005, 04:18 PM
Perfect Pass

etduc
09-01-2005, 06:10 PM
Just thought I'd help a fellow Tristar out. This is what I'm running.

I HAD to replace my heads last year. (Burnt valve) I bought two complete remanufactured regular heads (remanufactuered GT40 weren't in stock, but are available) for $320.00, local auto parts store. Did my own exhaust porting job. Now the boat sports a Edelbrock carb an orginal intake. Using an Acme 3 blade CNC, boat runs 45mph WOT, and has a whole bunch more bottom end.

east tx skier
09-01-2005, 09:49 PM
Etduc, that wouldn't happen to be your tristar at Ski 'N' Sport would it?

Remind me where you are again if you don't mind.

etduc
09-02-2005, 11:37 AM
Etduc, that wouldn't happen to be your tristar at Ski 'N' Sport would it?

Remind me where you are again if you don't mind.

Nope, but it's for sale. Lookin' fer a '92-95 205.

Live in Longview.

east tx skier
09-02-2005, 12:25 PM
That's right. I know I've asked before. We really should go skiing at some point. I'll keep my eyes peeled for that 205.