I have acquired the Hedmann headers for the 454, but I am having difficulty getting a response from the likes of Hedmann and Summit to complete the system with that Balance pipe.  I had planned to replace the exhaust with a more efficient system in order to improve the fuel consumption.....  HOWEVER...... I also....

After grounding out leaving a fuel station I have come to the conclusion that the LPG(propane) conversion for the engine, I had planned on, is a bit "iffy" to say the least when it comes to finding space for a reasonable size tank(s). The grounding really proves the point. I would hate to damage a Propane tank!  A lot of hump-back bridges and the like in the UK compounds the issue.

I have been offered the 6.5 Diesel V8 out of an Ambulance, complete with I think, a four or five speed auto box.

The questions on my mind are... Will the header fit the diesel? I assume, as it is the same engine maker(?) that they use the same/similar block and heads. Has any one done this conversion?

I worked it out that the LPG (Propane) conversion on the engine in the UK will POSSIBLY give a running cost equivalent to about 18MPG, where as the diesel I hope will return about 20-22 mpg.

Certainly the cost of the engine to me would be less on the install, with just some small modifications to the fuel lines and a tank clean.  It does mean that moving the levelling jacks and air receiver is not necessary to squeeze in the LPG tanks, that's a great bonus. I caried out a similar conversion from petrol 3.5 V8 in a Range Rover to a Nissan RD28 diesel engine, and that was well worth while.

Any comments would be gratefully received and acknowledged.

Chuck

Chuck,
I'm pretty sure the 6.5 is a small block casting so I don't think the headers are going to fit. Seems like you would not need them with a complete swap donor like an ambulance.

To be honest, I'm not sure about those mpg estimate either.  Have you connected with Chaplain Kent on ASF?  He has a diesel 280 and I don't think he sees those numbers.

Our diesel 345 doesn't get that kind of mileage either.  We get 12 to 16 mpg depending on towing and speed.  I like the power though.

Coop, thanks, I keep fogetting you have a diesel in your rig too. I can only dream of 12 - 16 mpg.

"MMMM" Now that's put the "Cat-amongst-the-pigeons!" - Small block.... low MPG... Mind you we are talking Imperial gallons... but then it will not make that much difference. I can get 12-14 on Petrol (Sorry - Gas) so perhaps it is possible on Diesel to get a little better.
I just returned from a 460 mile trip with a KarKaddy on the back with a Vauxhall Corsa on it. Up and down the mountains of wales and the South West of England and managed 10mpg or there-abouts.

Ah...an imperial gallon is 1.2 US gallons. (had to look that one up)

Cooperhawk gets roughly double the mileage I get in mine. Gas vs. Diesel...not to mention the torque and longevity of a diesel powerplant. When the time comes I hope to convert myself. I think using a donor would be the way to go.

UK Streamer, the 6.5 was GM's second try into the Diesel powered trucks after the failed 350 small block disaster!

The first was the 6.2 then the 6.5 turbo, and now the 6.6 Duramax. The 6.2 and 6.5 are a big block. If the engine you are looking at is not a turbo, don't bother. You will not have enough power to pull your rig. The 6.2 and 6.5 was designed as a diesel.

The headers you have, if it is not a turbo, I don't think will fit. GM did make some of the 6.5 without the turbo.

Take a look at this site, we are a bunch of diesel gear heads here and lots of great info on the GM diesels: www.thedieselplace.com

Good luck.

P.S. on your tank valve problems, I will reply to that post with some pic's of what I have done.

Chris,
There you are! Excellent post and thanks for the link. I've learned a lot already about the 6.5 from TDP. Got interested in these "cheap" GM engines after reading an article about rebuilding and adding a turbo kit to an older 6.5. Seems like a decent swap candidate.

from what I read the "stock" turbo 6.5 puts out 220 hp @ 2600 rpm and 450 ft-lbs @ 1800 rpm...with mpgs in the mid teens at 15,000 lbs.....sounds pretty good to me.

Chris , thanks for the site link - that will take some reading, and Steve thank you for your comments.

It is beginning to look a little more practical again, but there is a lot of reading and research to do before I take he plunge. I am hoping to view the diesel set up later his month. The Owner thinks it has a four or five speed Auto box and it is turbo plus inter-cooled - sounds promising.