engine and gearbox choice for hotrod truck

[rockcrawler31]

I've now purchased a 46 chev truck, it's nearly 3 tonne tare and about 8 tonne gross. I'll be using it (once restored) to haul my truck around the country as it gets more and more unroadworthy and also to just cruise and get away from it all.

Now i'm looking at engine options and i have to toss up whether to go large capacity V8 petrol, medium to large capacity jap diesel six (5-7 litre), GM two stroke diesel or a late model GM V8 diesel.
So i'm looking at people opinions on what is going to be most appropriate taking into account fuel usage, ability to actually pull that kind of weight without having to continually slow down on the hills on the highway, sheer fun factor, cost and longevity of the motor with that kind of load

So

Petrol V8 - I'm thinking 6 litre late model holden motor or larger perhaps. How will it go pulling 8 tonne? Just how thirsty is it likely to be? Will i save much by going straight gas and putting two dirty great tanks on it and what kind of mileage can i expect from gas? I've been told of an acquaintance who has bought a 6L crate motor for 4k from holden and is just sourcing prices for the accessories.

Jap diesel six from a hino or similar - Expensive initially (over 6 grand for a recoed old model motor up to whatever you want to pay for a later one), definately able to pull the truck and turboed should be able to stay on or close to 100 on the highway even loaded. Probably not so much yee hah factor or horn sounding, fuel usage? is it going to be that much better than a V8? Any brand suggestions to use or stay away from?

GM two stroke Diesel - Sounds horny as hell, probably a little thirstier than a diesel six, loves to be flogged mercilessly and gets good HP. But doesn't like to be just putted about and is a very heavy motor.

Late model GM diesel V8 - Great HP but lots of electrickery and $$$

So what are people thoughts

Also on gearboxes.

If i got a GM or jap motor with an SAE bellhousing then i could use a roadranger eaton box. Would i regret using a proper commercial box as i continually go up and down double clutching gears or is it not that bad, a question for the truckies out there.

I'd prefer to not have an auto box as i'll probably still be running drum brakes on the front and i want some engine braking ability.

[chimpboy]

Jap diesel imho.

Forget the petrol engines there is no hope of fuel economy with any of them for what you're planning.

Why not grab the engine and gearbox together from something?

[Matt_85Lux]

The jap diesel will give the best fuel economy and the only other I would consider is the Chev duramax (but will be thirstier than the jap diesel) as the petrols will be thirsty towing that sort of wieght.

The Chev we have at work (08 with the 6.6 duramax) gets about 22L/100km towing a 4.5 tonne van on the highway

[Eddy]

I have a 1978 4.4 Leyland Terrier (petrol) in the same weight range.
Unloaded I get about 14 mpg, with a best of 17mpg.
Full loaded (7.8 t) about 6mpg, & up to 9 on a good road.
Have spoken to a bloke with the same jigger on gas and he gets about the same figures, - petrol or gas.

I'd be looking for a diesel ... V8 for preference but Isuzu turbo six will give you plenty satisfaction.

MUCH help can be found here ... >> http://www.hcvc.com.au/forum/YaBB.pl

[bogged]

straight 8 something from the era...

[rockcrawler31]

cheers all

I've been to HCVC.com and it's a great site. I will ask there too but they don't seem to like rodders much

Bogged, if i could get a packard straight 8 into it i might but by christ it'd be thirsty

Has anyone ever heard a large jap diesel with a straight thru exhaust after the turbo? Do they sound less, well, truckish and more like a warmed over diesel like landcruiser and patrol diesels do?

[Eddy]

I've been to HCVC.com and it's a great site. I will ask there too but they don't seem to like rodders much

We DO like trucks tho...

[jaztaz]

Caterpillar 3208 (N/A 175hp, turbo 210-250hp) & 6spd Spicer or 9 spd Road Ranger, although IMO an Allison 6spd auto would be great.

[-Nemesis-]

Milo's truck is going to look so sweet, it already looks awesome as is! It's styling NEEDS big block gassed V8 goodness IMO, but might be exxy to run!


Any new BIG turbo diesel should suit, but cost to set up, it's a hard one. I saw a brand new F550 (yes, only one in Aus I think, it was 2 weeks old with full RHD conversion) over christmas. It was towing a full tri-axle trailer (about the size of a semi taught liner) camperhome, the combination should easily be over the weight range you are talking about. It took off like it was empty when he left, the big powerstroke twin turbo in it was so quiet too....

[chunks]

2 stroke diesel would sound farken horn!!

[fester2au]

I fthe money stretches I'd be looking at the 8 litre turbo diesel V8 GM plus matching Allison auto box, think same era and lineage as Duramax but not sure if the 8 litre is classed as a Duramax. Think it comes in the same age trucks but the big 3500's.

Or the 6 litre Dodge Cummins turbo diesel only because they seem to out out big power in the states but not sure of what it takes to make that power or how reliable they are at that power.

If you went petrol I'd think the 6 litre versions would be marginal, you'd have to go 500 ci big block either GM or Mopar. 500ci with supercharger would be sweet if you could keep gas up to it.

[mud_runner_GQ]

id say a ford 460ci big block running on gas, have 2 100l tanks in the back.
the old f250 tow trucks ran em.

[chunks]

With a dirty big garrett turbo strapped to the side Tom

[RED60]

Straight 8, 2 stroke birdfrightner..... come on gentlemen... stop playin' with it.... Isuzu or similar straight turbo 6 with the gearbox that comes with them as a unit...also if you want to impress get it from a 4wd truck and swap the lot... you WILL have to go to discs unless you want your widow/kids to get the vehicle when you die, how do you think some drums that were flatout pulling up the original load will go with twice that, so probably the square of the load on them, wake up....... if you want more HP, up the boost and fuel.... it will do the job easily and relatively economically....

[killalux]

I would say duramax, they are pricey, but endless performance upgrades available.
Don't worry about the electrics, I will soon have available a standalone harness to suit that will make it very simple.

Petrol V8 i think will be very hard on fuel pulling that weight.

Steve

[Harb]

Milo's truck is going to look so sweet, it already looks awesome as is! It's styling NEEDS big block gassed V8 goodness IMO, but might be exxy to run!


Any new BIG turbo diesel should suit, but cost to set up, it's a hard one. I saw a brand new F550 (yes, only one in Aus I think, it was 2 weeks old with full RHD conversion) over christmas. It was towing a full tri-axle trailer (about the size of a semi taught liner) camperhome, the combination should easily be over the weight range you are talking about. It took off like it was empty when he left, the big powerstroke twin turbo in it was so quiet too....

I saw that same truck going through Grafton when I was there......



I recon go with a Jap diesel and gearbox combo out of a wreck.
Isuzu or Hino..... I like the Hino's better these days but either are unbeatable

[fester2au]

I would say duramax, they are pricey, but endless performance upgrades available.
Don't worry about the electrics, I will soon have available a standalone harness to suit that will make it very simple.
Petrol V8 i think will be very hard on fuel pulling that weight.

Steve

What a coincidence Nice self generating recommendation there, although I do agree with you.

[rockcrawler31]

Straight 8, 2 stroke birdfrightner..... come on gentlemen... stop playin' with it.... Isuzu or similar straight turbo 6 with the gearbox that comes with them as a unit...also if you want to impress get it from a 4wd truck and swap the lot... you WILL have to go to discs unless you want your widow/kids to get the vehicle when you die, how do you think some drums that were flatout pulling up the original load will go with twice that, so probably the square of the load on them, wake up....... if you want more HP, up the boost and fuel.... it will do the job easily and relatively economically....

These are the drums that came with the truck designed to pull up 8 tonne. Drums are actually fine and pull up plenty of weight but suffer fade due to heat build up over PROLONGED braking. So therefore not so good in a race car but fine in a truck where it's pretty likely you'll have engine braking for prolonged descents. I don't mind the idea of discs, but if you can find a donor with a solid I beam axle with the same width, stub drop, and spring pad width and bolt pattern as the original 46 jelly bean rims then by all means let me know. I've driven air over hydraulic drum brakes that will put you through the windscreen, and there's still plenty of larger commercial vehicles still running drums.

I had thought of 4wd driving the front end but really, i'm not using it for that and it's extra unsprung weight, cost and complexity. What's wrong with jimmy diesels by the way? sound absolutely farking horn. But you're right, for parts availability and ease i think the jap option is the way to go.

But from what i've seen i'll be paying minimum 10 grand for a second hand runner donk/box combo of unknown quality.

[rockcrawler31]

Caterpillar 3208 (N/A 175hp, turbo 210-250hp) & 6spd Spicer or 9 spd Road Ranger, although IMO an Allison 6spd auto would be great.

I've been told to stay away from cat due to running and servicing costs. Can anyone here elaborate?

What do people think of a cummins 6BT intercooled?

We've got a vote for isuzu or HINO, What do people think of Mitsubishi or UD engines?

[rockcrawler31]

well, when i make the final payment this week sometime it'll be all mine. This is the beasty in question. Just long enough to fit a cut down troopy ute and carry it to 4wd parks and comps.

[v840]

I've got nothing to add other than AWESOME!!!!!

[265grunter]

392 v 8 and allison auto out of a 1982 international fire truck. pick up a truck for $5500 with only 180000 ks from caboolture,qld.stick it on impco gas gear and get 5ks per litre on gas at approx 55 c per litre.shitloads of torque up to 4000 rpm.when they designed and tested these motors they ran them at full rpm for 1000 hours......smooth as.

[rockcrawler31]

I've got nothing to add other than AWESOME!!!!!

Thanks dude. I seriously can't wait to get stuck into this thing. It actually drives still and just needs the front brakes fixed.

[rockcrawler31]

392 v 8 and allison auto out of a 1982 international fire truck. pick up a truck for $5500 with only 180000 ks from caboolture,qld.stick it on impco gas gear and get 5ks per litre on gas at approx 55 c per litre.shitloads of torque up to 4000 rpm.when they designed and tested these motors they ran them at full rpm for 1000 hours......smooth as.

Who made the 392's, how hard are they to get parts for and what size rad would it need to keep it cool?

http://www.youtube.com/watch?v=7368eCCw ... re=related

got wood?

[Loanrangie]

Isuzu 6BD1T or similar .

[Loanrangie]

392 v 8 and allison auto out of a 1982 international fire truck. pick up a truck for $5500 with only 180000 ks from caboolture,qld.stick it on impco gas gear and get 5ks per litre on gas at approx 55 c per litre.shitloads of torque up to 4000 rpm.when they designed and tested these motors they ran them at full rpm for 1000 hours......smooth as.

Who made the 392's, how hard are they to get parts for and what size rad would it need to keep it cool?

http://www.youtube.com/watch?v=7368eCCw ... re=related

got wood?

Inter made the 392's and a 345 V8.

[rockcrawler31]

Isuzu 6BD1T or similar .

I remember they 4BD1's in the army rovers, very torquey and bulletproof, but gutless as hell. I would hope the 6BD's are better per litre.

[chimpboy]

Isuzu 6BD1T or similar .

I remember they 4BD1's in the army rovers, very torquey and bulletproof, but gutless as hell. I would hope the 6BD's are better per litre.

Don't forget the T on the end. A 4BD1T has 50% more kw than a 4BD1.

6HK1 would be nice but not sure how common or cheap they are but if you could find a damaged isuzu truck you'd be right.

Make this guy an offer: http://cgi.ebay.com.au/Isuzu-6HK1_W0QQitemZ220553379395

AFAIK this motor can be tuned for anything from 200 to 300 hp and over 800 lb/ft.

[-Nemesis-]

Matte black and whitewalls FTW !!!!

[rockcrawler31]

Matte black and whitewalls FTW !!!!

At least it'll be cheap. chalk board paint and a house paint roller, whassat? about 100 bucks?