E85 500 HP 383 with a L31 truck intake

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Supercharged111

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Is it really a static percentage though? I thought it was closer to a constantish hp loss than a static percentage. I.E. if a 255 bhp truck makes 190whp stock, it might make something like 400 bhp/330whp modded. A 25% loss vs a 17.5% loss. I say this having not dyno'd a jillion different combos.
 

L31MaxExpress

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Is it really a static percentage though? I thought it was closer to a constantish hp loss than a static percentage. I.E. if a 255 bhp truck makes 190whp stock, it might make something like 400 bhp/330whp modded. A 25% loss vs a 17.5% loss. I say this having not dyno'd a jillion different combos.

Some of it is a fixed loss like a transmission pump. Trans pump is going to take X amout of power at Y rpm to make Z amount of pressure. Doesn't change regardless of what is powering it. However most of it is due to friction. Equal and opposite reaction. The more power you put through something the more force that tries to rip it apart and therefore the more loss into the bearings and gear faces. Its pretty much a static percentage loss. Doesn't matter if its a 2.2 or a prostock engine turning it. Also have to remember the inertia loss. More power made means it has to accelerate the drivetrain components and wheels/tires more quickly on an inertia dyno.

The loses are not fixed at any particular value either. The higher the rpm the more drag and friction. You don't lose as much through the driveline at lower rpm as you do at higher rpm. The faster you spin things the more drag it has to overcome, especially where rear end gears or transmission parts rotate in a fluid. You might lose 12% at 2,500 rpm input speed and 18% at 5,000 and 24% at 6,000. Windage drag increases with the square of rpm increase.

Automotive drivelines and marine drives are both percentage losses. I mess around with some prop shaft dyno stuff on Mercruiser Bravo drives. Doesn't matter if it is a 260 hp 305 or a supercharged 502 spinning it. It loses about 10% from crankshaft to propshaft.
 
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L31MaxExpress

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Pulled a muscle in my back and have not gotten around to dropping the 383 back in yet.

Just working on some small projects that are not too painful but preparing for the swap non the less.

Fitted the cooling fans to the shroud. I used the included zip ties to mount the fan to the shroud and then added 4 legs with cap screws, nuts and lock washers. Each fan is mounted at 8 points to the shroud now that I am finished. Waiting on the harness bits to finish the install. Also decided to go ahead and replace the knocking compressor and sticking rear expansion valve. Ordered a Sanden SD7H15 vortec replacement style compressor with the full a/c kit. While the a/c system is apart I am adding a GM A/C pressure sensor to the compressor discharge hose. Giving the PCM full control over the fans and more accurate torque mapping for the compressor at the same time. I will play with the on/off points in the tune when I get it up and running. Will have full control over the fans with both engine temperature and a/c pressure able to run the fans when needed. I added PCM control of the alternator a few years ago. Fans will be wired to run dual speed. Motors in series for 6V each on low and in parallel for 12V on high. Reduces the noise, the amperage draw and lets them live longer when maximum cooling is not needed. Wired in parallel with the radiator in front of the fans they draw 36 amps. Wired in series they draw 9 amps. On "low" speed they still move alot of air and with the full shroud there are zero dead spots of airflow into the radiator. Next task on my list is mounting the new transmission cooler. The top will mount directly to the oem bracket. The bottom is going to need some fabrication. Probably going to use a thin piece of bar stock rivited to the stock mounting legs and to the cooler.

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L31MaxExpress

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Forgot to mention that I also decided on a Flowkooler 1974 to cool this 383. Autozone stock replacement pump I put on it back in 2006 was seeping at the weep hole. $129.00 shipped ordering from Flowkoolers website.
 

L31MaxExpress

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Dang cheap Autozone parts, only lasting fourteen years! Take care of that back. God only gives you one.
It was not their cheap line, it was the premium line. Probably a $70 pump back in 2006. I definately got my use out of it. That being said Autozone lost most of my warranty file a few years ago on purchases made between 1994 and 2012 by myself, my brother and our late father. Their receipts of that era turn completely white over time even sitting in a filing cabinet drawer in my house. They will also swindle you out of you lifetime warranty parts if you do not watch them. Rather than swapping the item, they will return the old item and sell the new one, matching the price. Often times the new item is no longer lifetime warranty. Have to watch that crooked company like a hawk when I deal with them now.

Definately taking it easy on the back.
 

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Spent a few hours this morning putting new front brakes on the pig. Old rotors were worn and warped beyond repair. The front caliper pistons had been hanging up. New rotors, remanufactured calipers, new PFC carbon metallic pads. Also did the brake hoses and the wheel bearings. Replaced the beat up old dust caps as well. I used the front rotors for an 01-02 G3500 that are 39mm thick, like the dual rear wheel trucks and vans. The standard 1-ton rotors are 32mm thick. Also used the dual rear wheel pads and matching dual rear wheel calipers. Should stop even better with the larger front brakes. Still waiting on new coil springs and an OTC spring compressor to finish the front end and get it back on all 4. The old used 1-ton coil springs off a very high mileage van were sagging on the passenger side. Covid virus has had numerous things on backorder and some things with delayed shipping times for this project.

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On another positive progress note, my Flexalite OBS fan mounting kit showed up along with my new A/C Delco oil cooler lines. Waiting on my power steering cooler to finish out the core support changes. Engine install is tenatively planned for wednesday if I feel up to it. Coil springs and spring compressor should be here tomorrow and I am off Sunday to get it back on all 4, roll it outside and clean up the engine compartment. Still need to re-loom the harness and make the necessary changes to go back to a distributor and stock intake. Fun never stops. Should drive better than new when I am done though.

Once I get the engine into it, it is is a day or two away from driving again. Hopefully have it up and running by the first week of October. Get the engine tuned and new parts tested thoroughly and ready for a road trip this spring. Still need to get it aligned and inspected/registered again after it is running and tuned.
 
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L31MaxExpress

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Flexalite fan brackets look like they were almost made for the van. When I get the position set on them, going to have to drill a few more holes in it to allow me to reach the nutserts in the factory core support for the coolant bottle and some black paint should blend it in nicely.

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L31MaxExpress

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Calipers/pads??? ...or wheel cylinders/shoes? I wasn't aware of vans having rear discs.
Front pads and calipers are different for single vs dual rear wheel. The 01-02 van thick rotors use the dual rear wheel calipers and pads.

03+ vans have rear discs. Have considered a rear disc swap on it. I think swapping means an 03+ housing. Would have to swap my gears and locker into the 03+ housing or find an 03+ 4.56 geared rear with a factory locker.
 
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