Glastron CV19; re-engine.

[broompisces]

Hello all,
I have a Glastron CV19 that I started to refurbish some years ago then stopped the process for various reasons. I'm looking at starting the project again early next year. It has an Oldsmobile 403 cubic inch V8 (6.6 Litres!!) in it which has been stripped, re-bored, has many new parts and awaits re-assembly. I only ran the boat once before stripping it to start the refurb. During that run, the petrol consumption was very scary. So, I'm thinking of putting another engine in it for increased power (I'm told the Oldsmobile engine puts out 180hp) and better fuel economy. Any engine needs to mate directly to a Berkeley jet drive. Does anyone know of an engine that would be an ideal candidate to substitute for my current power plant? I'm not looking for a car engine that can be converted for marine use, I'm after a marine engine that can be dropped in and mate up with the jet drive and (hopefully) the engine mounting points on the hull. The link to the original refurb topic post is here; viewtopic.php?f=6&t=2230
Many thanks in anticipation of advise / help / inspiration.
Ian.

[solitaire]

Hi broompisces (from another Glastron CV owner) I can offer a few thoughts from previous experience
1st - 403 CID is a funny one for a GM block - the closest is 402 CID (perhaps the extra "1" is allowing for the re-bore!) if you pm me the casting number from the back of the block(8 or 9 digits above the flywheel) I will get back to you with the correct CID and date....
and only 180hp seems very low! - the small block 350 cube Mercruiser has been rated at 260hp in marine guise for decades - I would have though your .400 CID big block would be pushing close to 280/300hp.

Looking at your previous post it seems to have the correct carb for fuel economy - the Rochester Q jet is good for up to 400hp, many people have rushed out and bought big CFM Holley "double pumpers" (as I did) only to use much more fuel and have more induction noise

All of these GM based engines are ex car or truck engine and the quality of marinisation depend on how much research and money the marinising company spent.... Mercruiser engines are by far the best (in my opinion), they even worked with GM on the inlet manifolds to have them cast with a bronze water crossover passage!

- unfortunately these days, a good deal of so called GM "marine" engine sellers are offering crate engines that are built to car or truck spec. with the wrong pistons, camshaft, con rods and even cylinder heads for operation on the "propeller curve" - for example - take a regular 454 CID engine:- GM build their engines engines with 3 different types of piston material and 7 different piston heights! - cast alloy pistons for highway use that will not last more than a couple of hours at WOT in a boat - Hypereuctic pistons which are correct for marine use and for serious hp - Forged pistons are a must.

Sadly more HP = more fuel consumption especially with the older GM engines using a carburetor, (when fuel was well under $1.00 a gallon). From my own experience and hundreds of hours running a 454 CID 400hp Mercruiser, the fuel consumption at WOT is 25 gallons/hr. and that figure can be doubled if you constantly work the throttles , the accelerator pumps chuck fuel into the engine by the bucket load (and even bigger buckets with a Holley carb.

Carefully building a GM big block can certainly give you as much as a 30hp increase, the GM base engines are very crudely built - deck height is all important as is a nice 3 angle valve seat, and above all - the correct marine parts (as mentioned) - I tried a GM high performance tall inlet manifold once, and our 70 mph boat just gasped and could hardly get on the plane.

The later Vortec engines are much better on fuel economy and better still anything with fuel injection, personally, If that lovely CV19 was mine - I would keep the original Berkley Oldmobile, - build it nicely, make sure the timing is spot on, and the carb is correctly jetted, keep off the accelerator pumps and enjoy the noise the V8 makes.....

[broompisces]

Hello Solitaire,
Very many thanks for your comprehensive reply.
I won't be able to access the numbers your requested for a while as I can't get to the yard for some time yet. I attach a few pictures of the engine - not that you'll be able to tell anything from them - but mainly for interest. I got a rake of new parts some time ago from a supplier in Iowa - hugely knowledgeable about the Olds engines and sent me over pistons, cam, lifters etc, etc. I will be rebuilding the engine in January (everything being well). I know what you mean about sticking with the Oldsmobile and enjoying the rumble of the V8 and living with the fuel consumption. At least I know it all mates up to the jet drive correctly. All my online research tells me that the 403 only puts out 180hp. If I stick with it, I'm hopeful of maybe 210hp with the new "hot" cam and the overbore that has been carried out already.
Best wishes,
Ian.

[pspeed]

Drove one of these years ago, it belonged to a friend (mint metalflake blue one) what a piece of kit!

I agree with the above, I would re-fit the Olds engine and forget about the cost of fuel, also it will keep the value in the boat.

The Olds engine is a dedicated lump (according to their wikipedia page they didn't start using the standard GM lump until the 1990s) and not sure if the GM bell-housing would marry up with the pump, and to be honest you wouldn't be any better off fuel wise, its still a 350ci V8 and Jet drives aren't that efficient anyway.

Here's the wiki page on the engines and there's a few US sites doing various adaptor plates, but I'd stick with it.

https://en.wikipedia.org/wiki/Oldsmobile_V8_engine#403

P

[eastcoast]

Solitaire, sorry to hijack the thread but I'm interested in your comment of std car V8's not been capable of sustained wot.
I have a Boesch 510 which was fitted with a crusader 260hp v8 but sadly the previous owner left the block to freeze and crack.
I was going to replace with a new crate engine from roadcraft but was not aware of the cast piston issue?
I kept the original crusader crank & pistons which I assumed to be std GM ones.

Any advice appreciated

Regards Paul

[solitaire]

Paul - PM sent - but here is an extract from the big bock tuning manual
In summary:
Cast Pistons
Standard automotive piston for decades, cheap and easy to produce,good grain structure, under normal use, good for 10's of thousands of miles however - they have limited speed, thermal and detonation resistance - only used in moderate performance engines where speed is limited and detonation strictly avoided

Hypereutecticf Pistons
Castings have nearly 2.1/2 times silicon vs standard cast, increased hardness and greater resistance to high temperatures and cylinder pressures, engines can be built with smaller clearances leading better sealing and blow-by control - well suited to High Performance, but not to be used with high Nitrous Oxide loads, high pressure turbo or supercharged applications.
As far as I know - Mercruiser use this type of piston for pleasure boat engines (but not the 4 cylinder post office van 140/3.0l engine)

Forged Pistons
Top Choice for Racing, Turbocharged, Supercharged and Nitrous Oxide injected engines - Used by Mercruiser/ Chief and others for big HP Race engines

[solitaire]

re Olds v GM engines - I stand corrected on that one, I had thought Olds were using GM blocks much earlier.

Slightly off topic but of interest, - - I should have know as we were running 4 test beds with 455 CID Olds engines in the UK in the 70's - running API and US Mil Spec rust tests 34 hours at 1500rpm very light load and refrigerated coolant in the jacketed sump and rocker covers, (sump oil level increases almost an inch with water from condensation) then 2 hours at 4500rpm maximum load and maximum temperatures to boil off the water and bake the rust onto the engine components.
The push rods and hydraulic liftes had to be removed within 1/2hr of the engine stopping to evaluate how good the test lubricant was at dealing with rust - the rest of the engine was dumped!!! 4 engines every 2 days

The engines we used were from the Oldsmobile Toronado - 455CID but with a weedy twin choke carb

[Rapier]

Great posts!

[pspeed]

Poor old engines, that was torture, all in the name of oil eh.

However, on fuel economy, here's a thought- a friend of mine runs a hotrod with a BBC in it but he's just converted it to TBI with a kit from the US and is hoping to save a load on fuel, he says you can go in and play around with it and set it up for whatever use.

Might be worth a thought.

Found this link, not sure if you'd get an adaptor for yours though, you'd have to ask http://news.pickuptrucks.com/2013/04/qu ... ickup.html

[Alacrity]

Cast Pistons
Standard automotive piston for decades, cheap and easy to produce,good grain structure, under normal use, good for 10's of thousands of miles however - they have limited speed, thermal and detonation resistance - only used in moderate performance engines where speed is limited and detonation strictly avoided

So if you have a small block in say a Boesch or a Riva Junior for example, which would generally be running around at about 2 - 2.4k with perhaps the odd blast, a simple twin choke carb (Junior) or poss a simple 4 choke on the Boesch, would these cast pistons be an issue? Or is it just if you are racing & pushing it hard? I know of three people who have bought crate engines & have them, or are about to put them in, this type of boat.

As Rapier says, great thread this one.