Last post on Jan 10, 2009 at 7:25 PM
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Chevrolet Chevy Van, Van
#5 of 9 Re: Unusual conversion van project. [scvanman]
Jan 17, 2008 (7:18 pm)
After a year in my car port I just pulled my 1985 g20 out. I have swapped in a 1998
fuel injected vortec 350 4l60E Trans and a 33 gallon fuel tank. I will let you know what my fuel mileage is when I get it all the way on the road. I was getting 10mpg with the last engine but I had put a cam and aftermarket carb on it. It never ran the way I wanted. It has 4.10 gears and a limited slip rear end which does not help mpg any,but with the overdrive trans it puts the rear ratio around 3.73.
good luck on yours
#6 of 9 Re: Unusual conversion van project. [scvanman]
Feb 21, 2008 (2:44 pm)
Any updates? (Nevermind my old questions. The rear AC units are way more trouble than they're worth and come out quickly, btw). Been researching engine builds, and it seems like a shame to replace your middle-aged 305. I have the same drivertrain and adding an OT gear and a light rebuild seems like the best option. Intakes have the most impact by far, followed by compression, cams (RV?), bigger wheels... Exhaust upgrades and weight reduction are especially worthless for highway. The idea is to bump up efficiency enough to both gear it a bit taller (3.10...) and run lower (2000?) rpm at choice speed, no? Do we know the rpm's for the factory stall converters? Most truck forums are posting better mileage with 350's, but I'm sure that's just because they're geared more efficiently; there's less compromise between towing capacity and higher gearing.
At any rate, once you start messing with pistons and heads and pull the engine, why not put a 350 back in while you're at it? Heck, why not a turbodiesel like the 2.7's out of the Sprinter (27 MPG!)? Point is, 305s are cheap, especially if you're the kind of guy that gets a van for $1, and working in that doghouse is a PITA. If anyone has 305 setups geared for highway cruising that info would be amazing...
#7 of 9 Re: Unusual conversion van project. [scvanman]
Apr 23, 2008 (8:57 am)
I have an 85 G20 van with the 305, auto,ac the works. Like yourself, I haven't been able to find who did the conversion. When I bought it ($600) 3 years ago, It ran fine (minus one water pump replacement) it also had the Cruise Control which still worked! Had 155,000 on the original eng. Got 13-15 MPG. After having it for about 3 months (Daily Driver) it blew the head gasket. A lot of carbon build up in the intake. I've since replace the motor, then got the same GPM. After that the Tranny went, I replaced that,and the Emissions letter came. Brought it to a place and it failed miserably. I ran out of money at the time to fix. I'm Just about to replace to Carb. I'll let you know what happens..
Mine came original with the 34 Gallon Tank. There is one problem with this tank, is that you can't take of the rear Differential cover off without taking the tank down.
I might have the same AC/Heater unit that you have, my AC was disconnected before I got it. So I have no Idea what's working or not. The Heater part works fine since I live in NE. But the Summers are less than Ideal. If I find any info on the case I'll let you know.
This is the first site that I've found that even remotely resembles the problems that I'm having. If you have any info that you would like to share send it along..
Thanks, I hope that I helped a bit...
#8 of 9 Re: Unusual conversion van project. [scvanman]
Jan 10, 2009 (7:25 pm)
i know that you can swap conversion van springs and spindles to a caprice and they will bolt right up and keep the same bolt pattern. so i would think that you could do the reverse to the van and it would lower the front. when it's done to the 91-96 caprices it gives them around a 3" lift in the front, so there for in a sense it should lower the front of the van around the same.