RePowering 311 SRI to Diesel
 

Just to set the scene gasonline in the UK $1.50 per liter marine Diesel in the UK $0.50. liter.

Ok so i need to convert my current twin chevy 502's w/6.71 blowers to diesel units.

I want to run at 70mph as with gas but not sure which diesel engines are compact and cost efficent enough to do that. The boat must be able to run at least 55mph. Any slower it will detract from its re sale value.

didn't want to spend anymore than $4k per engine for recon/second hand units

Can anyone suggest what engines to use.

GMC 6.5 V8 - not much horse power masses of torque what will this translate into all out speed?

Volvo KAD43 - 260hp straight 6 may be too big to fit it.

has anyone tried this converstion?

Re: RePowering 311 SRI to Diesel
 

Neat idea :cool: . But I can't imagine finding a decent diesel for $4000 (america) much less 2 of them :eek: .

Re: RePowering 311 SRI to Diesel
 

You won't get them diesels fro that kind of money--but check out Yanmar--they have some really well engineered outdrive packages and design is simple and elegant

Re: RePowering 311 SRI to Diesel
 

Chine Walker--
Just curious if you ever figured out the gas fume issue on your 311? You posted earlier this summer but never did catch the outcome. Diesels would be cool but much more pricey than 4g a side. Good Luck
PM

Re: RePowering 311 SRI to Diesel
 

Diesel power is expensive more like $25K per side and anything that makes the kind of power your looking for (GM8v92, etc.) will be quite large in size, weight, etc. not really a practical package for 311 if you want 55+. Better to sell and buy something already diesel powered???

Re: RePowering 311 SRI to Diesel
 

i can get two turbo charged 225 hp 400 ft t 6.5 re enginered GM engines for £6k a piece around $10k.

The plan was to put these onto Volvo DPX duo props which are $7k a pair for year 2000 ones

plus fitting etc

Not sure what speed this would translate into.

Apparently getting any more than 250hp from these motors becomes expensive aftercoolers, propane injection etc

Re: RePowering 311 SRI to Diesel
 

Not to bash your idea but,,,,,,,,,, it doesn't seem viable to me. All said and done, you'll be sitting on an expensive white elephant. :(

Re: RePowering 311 SRI to Diesel
 

You said the RESALE word. If resale means anything to you at all, then leave it alone. If you're doing this for your own kicks, then have at it.

Diesel costs .50 versus 1.50.
Fast cruise with gas costs 35 gallons per hour (135 liters per hour). That's $200 per hour.
The diesel will burn 20gph (75 lph) that's $38 per hour.
So you save $162 per hour at 45mph?

The $20,000 you'll end up spending will result in a 55mph boat that takes 190 hours to "break even". It's worth the thought, but you shoudl only tackle it if you are ready to absorb costs in excess of what is expected. Plus a hit on resale.