Being a 2002 your van already has the good air intake setup, the 0411 PCM and a few other improvements.

I pull a 6,000 lbs Jayco travel trailer and it has no trouble pulling it 70-75 mph down the interstate.




Some mod pics

Marine Intake/454 Vortec TB


Marine cam swap


And yes I actually did run this thing with the carb and the Vortec electronics. It was a test to see if I could use the 0411 as an ignition/trans controller on a carb LS swap and it worked beautifully!!! The LS setup has since been built and also runs GREAT on it. The little Marine cam with a spreadbore vortec dual plane intake and 650cfm mechanical secondary q-jet replacement double pumper had AMAZING punch and surprising fuel economy. Staying out of the secondaries I was getting 14 mpg city/20 highway on the somewhat lean jetting I was running. It got 1/3 those numbers when I discovered I could change out the metering blocks, fatten up the jetting, then with how torquey it was I started kicking in the secondaries out of every stoplight!!! I already owned everything to make the swap happen and just tried it out to gain knowledge. I mounted a TBI TPS to the choke housing and linked it to the carb primary shaft. Used a 5.9 Jeep air intake bonnet that went right on the carb and hooked up to the stock MAF and air box. The PCM only needs, crank, cam, TPS, MAP and ECT to properly run the trans and the ignition. Almost all engine DTCs can be disabled and the applicable tables Zero'd out. Honestly I probably could have snuck it through smog as well hidden as the carb is and the fact with most DTCs disabled the PCM shows ready nearly immediately.


0411 swap


Hydroboost with the 0411 peaking out.



4L85E swap


Thorley Tri-Y Express Van headers


Where the headers contacted even with energy motor mounts


Exhaust








200a AD-244 Alternator, charges 4 batteries


Duramax Fan/TBSS Fan Clutch


I have a G3500 454/8.1 radiator and upgraded to the factory oil cooler setup.



I ran Tahoe E-fans on it but would not recomeend them for towing. Could not keep the 350 cool going uphill.





As this HP Tuners screen shot can attest, had ZERO issues in the power department even with the little Marine cam.



This was actually one of the first things I did when it was stock. It had a drop-in K&N and I had added a 70mm bored CFM Tech throttle body. 1.6:1 full roller rockers from Jegs and a March Underdrive 3-piece pulley set. Those 4 things were a nice shot in the arm on an otherwise stock engine.

 

It is not an easy swap at all. The doghouse opening was changed on the factory LS vans as was the frame section up front. The LS based engine is a very tight fit and serviceability is very poor when stuffed into the 96-02 350 opening. I tried to wedge an 8.1 in a frame donor I was tearing apart for mine and short of cutting the firewall and floor for the larger 8.1 dog house, using the 8.1 mounts that offset the engine 6" back and 4" to the right, it was not going to happen.

Factory LS Van


Factory 350 van stuffed with LS.





This van was later fitted with a Magnacharger.

 

So I happen to have a 1987 G20 that fell into my hands with 104K miles on it. My brother and I are building it for him to travel across the country and to Alaska. We were going to mess with the 305 TBI, reseal it and put a RV cam and headers on it and reseal the 3L80 (TH400 with 350 output shaft or TH375). However looking at the list of parts to buy decided to go with the 2006 6.0L I picked up a while back for $350. Probably sticking with the 3L80 in it since the Van has 3.08 gears and will only turn 2,500 rpm at 70 mph anyway.

Stock 305 coming out.




I am actually planning on going DBW with this swap. Accidentally used a Hemi Ram pedal I had laying around for mockup. After discovering it was a Dodge pedal I pulled the wiring diagrams for both the 2006 Ram and 2006 GM trucks. Did some testing of both pedals with my Fluke. The resistance values seem spot on with the GM and I believe it will work with some repinning of the connector.

 

Fast355, start a build thread.. I will subscribe. I will be following it. My Van will be started next year after I finish refreshing the engine in my 84' Z28..

 

Fast355.. start a build thread.. I'll be following it. My VAN is next in line after I finish refreshing the engine in my 84' Z28 and finish a few other small projects.. hopefully next year I'll start collecting parts.

BC

 

MY 1983 G20 is in line after this one and tuning my 1997 Express post head/cam swap.

The 1983 is getting a 2001 8.1 with the 502 HO cam. The 8.1 is already sitting in it backed to a 9" tail TH400. I just have alot of other issues to address after sitting for 4 years and not having been driven on the street in 10.

 

Dido... Do many projects and not enough time..

 

My current van has 195K miles, my towing trips to the Gulf of Mexico just over 230 miles one way Concerns me.

I've decided the easiest way for me is to just buy a 03+ conversion (the 5 door/30 gallon fuel tank will be very handey)w/ at least a 5.3LM7
preferable a 6.0. (I think both came w/ 4L80?) then just install mild cam would like some LTs/duals tune then have a decent tow vehical / sleeper.

Crunching #s the 5.7 vortec is no slougch 255hp 330ft. lbs weight 7100lb
The 03+ stock 5.3LM7 285hp 330ft. lbs weight 8100lb will
Probabley be less powerfull because of the extra 1K in weight?
The 02 an older is a sleeker looking body.

I’ve read the 5.7 vortec heads have excellent flow #s and folks use them on older 350 builds, so rebuilding is a possibility.

Fast355 the marine cam/intake/carb is interesting, very nice of you to post about it what are the cam specs.I like a mild cam. From you’r advice my 02 won’t need intake/carb just cam will my LS1 crane valve spring tool Work on the vortec springs/what length push rods?

Edit: I’m thinking you have at least 600lb of tongue weight on the trailer? Will you brothers van tow a big trailer from TX to AK.

Fast355 you van doesn’t squat low like mine what type of rear springs/load levelers are using?

I looked and looked could find a raditater drain plug is there one?
Thanks Guys for advice

 

bump van thread
will the LY6 be a direct boltin on a 03 express 1500 w/5.3 I think LM7? like wiring is LM7 and LY6 of which error will direct swap?

I may have a deal on a 03 1500. but need minium 400hp.