To install a reliable and efficiant diesel engine into a lifted 4x4 Astro that is to be used as a daily driver. We want to go with something that is somewhat common, comparable in size and with enough power to provide acceptable performance on and off-road. Contact me here with any ideas.
Why?
BioDiesel is the main reason. We want to be able to run our van on home made fuel. You can run a diesel engine on WVO (waste vegtable oil) for free or produce your own environmentally sound BioDiesel fuel for a fraction of the cost of gasoline. Besides diesels sound cool and have lots of torque.
Findings:
In the early Astro vans a 2.5 inline four gas engine was standard that only had 95 HP and 134 pounds of torque. The latest Vortec 4.3 V6 has 190 HP and 250 pounds of torque. The 4 cylinder was considered underpowered and eventually phased out.
GM Diesels:GM has offered diesel engnes in the full size van but never for the Astro/Safari vans. Because space is at a premium in the Astro's engne compartment the GM 6.2 and 6.5 V8 engines would be a tight fit. The 6.5 Turbo Diesel would be even tighter. These engines are not known as steller examples in performance or longevity although there are changes you can make to them better in both regards.
VW Diesels:At the other end of the spectrum you have the reliable but small VW made diesels. Although VW put one of it's 1500cc diesels into it's relatively heavy Vanagon (circa 1982) it proved under powered. VW makes larger and turbo charged diesels that are very dependable and some have even been swapped into small SUVs. We were unable to find any info on fitting them to the GM tranny and our general feeling is they are still too small either.
Isuzu Diesels:Another possable swap is the Isuzu 3.9l diesel 4BD1T. It was used in Isuzu NPR series cab-forward trucks and I also believe it was used in the GM Forward 3000-4000 series trucks. It is a turbo charged four cylinder that produces 120 HP and 250+ lbs. of torque. It has been swapped into some SUVs and seems to do well. It has a SAE #3 flywheel cover and can be mated to a GM bellhousing via an adapter ring.
NOTICE
The products and vehicle modifications discussed and/or promoted by this site are for use at your own risk. Due to the nature of these products and their intended use Overland Vans and any parties associated with it will not be responsible for any claims against them. No collision studies have been performed pertaining to any of these products or the use of them on a vehicle. Off-road use of a vehicle can be dangerous. Lifting a vehicle raises it's center of gravity and therefore may be at higher risk of rollover. Caution should be used in driving any lifted vehicle. Use caution also in installing any products to your vehicle. Failure to properly support a vehicle while working on it could result in injury or death.
Dare to be Different!
022507 Gathering Data:
I contacted Cummins for more information on the 4BT and was told that many commercial customers and independent shops have used this Cummins engine. The 4BT 3.9 engine is rated at 120+ hp @ 2500 rpm with peak torque of 327 lb-ft @ 1700 rpm. The engine weighs 570 pounds (dry). The 4BT 3.9 engine dimensions are...:
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Total height: 30.6 inches
Total length: 30.1 inches
Total width: 22.9 inches
How does that compare with the stock GM 4.3 V6? It has 190 HP and 250 pounds of torque. It's dry weight is 492 pounds.
Total height: 26.7 inches
Total length: 26.0 inches
Total width: 22.0 inches
I'm not sure if that height refers to the oil pan also. I'll have to look into that. It may also include the intake tube that runs over the top of the engine. That could be rerouted. I also found out that some have a front sump (CPL 1839) oil pan while most have the rear sump. The rear sump appears to be the best choice for an Astro.
Cummins ISB 3.9
This site was an excellent sorce
for information on diesels.
GM Vortec 4300
Cummins 4BT 3.9
Taking measurements of the Astro's engine compartment showed it to be about 25 inches wide, 36 inches deep and a little over 30 inches in height. A subframe spacer kit could provide some additional inches there. All-n-all it looks like it's do-able without too much grief.
Finding our Cummins:
The next task is to line up an engine and the other parts needed for the swap. I have learned that there was a repower program that put Cummins 4BT engines into Step Vans that had tired 6.2 GM diesels. There are thousands of these out there and so it shouldn't be to difficult to find one. Besides the ones that replaced the 6.2 were bolted up to either a TH400 automatic or a SM 465 stick. This means adapting them to the Astro's 4L60 (700R4) shouldn't be too hard. Or we could go with the TH400 and a NP205 transfer case. Decisions, decisions.
030107: We are currently looking for a sponsor for our project. We have been communicating with someone who deals in thousands of these engines. If all goes well we will have our engine soon and the information on who to contact to obtain one for yourself.
032507: I came accross an interesting product on the web. A company called Phoenix Casting makes an adapter to fit diesel engines with SAE bellhousings to automotive transmissions. It looks like this may be the ticket to mount a Cummins engine to a GM tranny.
Stay tuned to this on-going projet.
Updated March 26, 2007
Cummins: After doing some research we think we have decided on
the way to go. The Cummins 4BT or ISB 3.9 liter turbo-charged four cylinder looks like a good fit. This engine can be found in some Ford
E350 cube vans, Chevy/GMC P30/P3500 step vans, and Case 580 Tractors. This ISB puts out 145-170 HP and 420 pounds of torque. That is 80 pounds more than the 6.0 Vortec V8. Unfortunately the ISB is so new the chance of getting one used is slim. Buying one new is a little too rich for our project so we decided the 4BT would be the one to look for.
