Plans for the project truck

"G_Body_Man: Sponsored by the number 3" (gbodyman)
09/03/2015 at 10:56 • Filed to: None

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I figure that even if I have to do some dremeling and grinding to make it all fit, it will still be worth it. 450 horses for a $2k overall investment? That’s NP all day, everyday. Plus, when I inevitability blow up the 4.8 I’m swapping in, I can always go back to stock, or rebuild the motor. I know of the risks involved, I just want to try it. Is that wrong?

DISCUSSION (38)

deprecated account > G_Body_Man: Sponsored by the number 3
09/03/2015 at 10:59

What truck and what 4.8?

RamblinRover Luxury-Yacht > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:00

It’s all fine, unless the car catches on fire and heats up to 10,000BC.

crowmolly > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:00

Link to kit plz

G_Body_Man: Sponsored by the number 3 > crowmolly
09/03/2015 at 11:00

I’ll link you to the bits and pieces, gimme one sec.

Snuze: Needs another Swede > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:05

No, not at all. Those 4.8’s are pretty bulletproof as well, just keep the boost moderate.

Smallbear wants a modern Syclone, local Maple Leafs spammer > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:06

Blow up a 4.8? nyet.

G_Body_Man: Sponsored by the number 3 > crowmolly
09/03/2015 at 11:06

http://m.ebay.ca/itm/LS1-LS6-LS…

Manifolds

CB > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:06

I thought you were supposed to put superchargers on those kinds of engines, not turbos.

G_Body_Man: Sponsored by the number 3 > crowmolly
09/03/2015 at 11:06

http://m.ebay.ca/itm/Brand-New-…

Turbo

G_Body_Man: Sponsored by the number 3 > crowmolly
09/03/2015 at 11:08

http://m.ebay.ca/itm/Brand-New-…

Flange

G_Body_Man: Sponsored by the number 3 > crowmolly
09/03/2015 at 11:09

http://m.ebay.ca/itm/CXRacing-I…

Intercooler

Smallbear wants a modern Syclone, local Maple Leafs spammer > Snuze: Needs another Swede
09/03/2015 at 11:09

No moderation needed.

http://www.hotrod.com/how-to/engine/…

G_Body_Man: Sponsored by the number 3 > crowmolly
09/03/2015 at 11:11

http://m.ebay.ca/itm/BLUE-WG38-…

Wastegate

G_Body_Man: Sponsored by the number 3 > crowmolly
09/03/2015 at 11:12

Downpipe, exhaust, and intercooler piping will be fabricated by yours truly.

G_Body_Man: Sponsored by the number 3 > deprecated account
09/03/2015 at 11:13

A GMT400 with a junkyard 4.8 with new rings to restore compression and reduce accelerated wear.

G_Body_Man: Sponsored by the number 3 > RamblinRover Luxury-Yacht
09/03/2015 at 11:14

As long as I don’t overcook the boost, I’ll be fine

G_Body_Man: Sponsored by the number 3 > CB
09/03/2015 at 11:14

Turbos are cheaper and more efficient.

Smallbear wants a modern Syclone, local Maple Leafs spammer > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:15

Widen the ring gap while you're at it. It'll handle the boost better.

crowmolly > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:15

I am a bit skeptical of these. Have other people run them with success? That’s balls cheap for a set of stainless headers on ANYTHING, let alone an app like this. Does the truck have an AIR pump or EGR to worry about? What do you do about the front O2 sensors?

The first thing I’d do is check the flanges for flatness, even before taking them into the garage.

deprecated account > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:17

Is a 4.8 a 283? Just not a common/well-known displacement (to me at least).

G_Body_Man: Sponsored by the number 3 > Smallbear wants a modern Syclone, local Maple Leafs spammer
09/03/2015 at 11:18

I really should. I might as well also run a methanol injection kit to reduce the chance of detonation.

BigBlock440 > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:19

No, it’s not wrong. I thought you didn’t have the money to fix your G-body though, how are you going to do turbos? And would it even pass the seemingly strict inspection that your other car wouldn’t?

Smallbear wants a modern Syclone, local Maple Leafs spammer > deprecated account
09/03/2015 at 11:19

Gen3/4 SBC. Basically a destroked 5.3L, the block and bore are identical.

G_Body_Man: Sponsored by the number 3 > crowmolly
09/03/2015 at 11:20

I’m skeptical too, but a couple of $2k challenge guys have run them without issue. As it will be an LS going into a GMT400, I’ll see if I can be one of rusEFI’s guinea pigs. I’ll be running a wideband, with an AF ratio gauge to assist tuning.

Smallbear wants a modern Syclone, local Maple Leafs spammer > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:21

Interesting link for you then.

http://www.alcoholinjectionsystems.com/a48/What-Type-…

deprecated account > Smallbear wants a modern Syclone, local Maple Leafs spammer
09/03/2015 at 11:22

Oh ok. GMT 400 is pretty sweet too.

G_Body_Man: Sponsored by the number 3 > BigBlock440
09/03/2015 at 11:22

I had the money, it just wasn’t worth it for me to fix it, when it costs more to fix and transport than the car was worth. The inspection plan is that it only needs an inspection on purchase. Everything after that is open game.

Snuze: Needs another Swede > Smallbear wants a modern Syclone, local Maple Leafs spammer
09/03/2015 at 11:23

I’ve seen that before, and it’s completely insane. But I question how long it would live at those power levels under real world abuse. Note they did their testing with 118 octane racing fuel. I think 27 psi would be tough on pump 93 octane.

I’ve done a fair amount of investigation into boosted LS motors for a project my dad and I are working on, though I’ve been more interested in the 6.0L motors. That said, I think this combo with a moderate amount of boost (around 14-15 psi) would be very doable safely and cheaply. At 15psi they hit over 900HP but consider they also had ported heads, intake, cam, etc. I think on a completely stock motor you’d be more like 700-750. But that’s also still COMPLETELY INSANE for daily use.

G_Body_Man: Sponsored by the number 3 > Smallbear wants a modern Syclone, local Maple Leafs spammer
09/03/2015 at 11:23

Thanks!

Dogapult > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:28

Don’t buy a random ebay turbo. or if you do. get a genuine rebuild kit and rebuild it before sticking it on your vehicle.

BigBlock440 > G_Body_Man: Sponsored by the number 3
09/03/2015 at 11:29

Sounds like a plan then. As long as you don’t have to rely on it as a DD, should be a fun project.

G_Body_Man: Sponsored by the number 3 > Dogapult
09/03/2015 at 11:30

EBay turbos are fine. A bit weak in the power department, but fine for my application. Its the manifolds that will be the big gamble. But I can get in there and clean them up so that debris won’t end up in the turbo.

G_Body_Man: Sponsored by the number 3 > BigBlock440
09/03/2015 at 11:31

I may daily it, but at first I won’t rely on it as a daily.

Smallbear wants a modern Syclone, local Maple Leafs spammer > Snuze: Needs another Swede
09/03/2015 at 11:36

Yeah, there’s no way you could run those numbers on 93, at least not without a good bit of octane booster.

I personally think the 4.8 is a great motor for boost, since it’s just a destroked 5.3L. I’m in agreement on the stock motor part. Another point though—you’ll notice that they also increased the ring gap. Without pushing the rings too far, you could probably have a reliable 550-600hp, but even that's lots. And if you were going to change the rings, which it looks like he's doing, you might as well do the rest as well while you're in there, imo.

Snuze: Needs another Swede > Smallbear wants a modern Syclone, local Maple Leafs spammer
09/03/2015 at 12:45

I agree with you 100%. You definitely have to do the fuel injectors, no 2 ways about that. I don’t have links or anything handy but if I recall, the factory injectors are almost maxed at 80% duty cycle as it is.

If it were me, I’d also do MLS head gaskets and head studs. Some cheap insurance that’s easy to do while you have the thing apart anyways.

Also, I’m not an LS head expert, but you could probably hand port and pick up a few ponies. When I was in FSAE we ran a CRF450 dirt bike engine, and I was able to pick up about 5% more power on the dyno just by spending about 2 hours with a die grinder and dremel tool, cleaning up casting flashing and radiusing parts of the port. Really, really mild job but it was a consistent 5% boost for free. (5% on that engine was like 3 HP)

Also, I don’t know what style 4.8 heads are, cathedral or square port, but they only came with truck intakes. I’d probably snatch up either an LS1/LS6 or LS3 intake as I’ve heard they flow much, much better.

Smallbear wants a modern Syclone, local Maple Leafs spammer > Snuze: Needs another Swede
09/03/2015 at 13:02

Agreed.

I believe the truck heads have a lot of room to play around (as in, they really aren’t made for much performance), you probably wouldn’t hurt anything doing a hand job (hehe).

All 5.3’s and 4.8’s are cathedral iirc. Personally I’d take the same route and put on one of those intakes while I had it apart.

All subject to budget of course.

Snuze: Needs another Swede > Smallbear wants a modern Syclone, local Maple Leafs spammer
09/03/2015 at 13:32

My dad and I are looking at doing something very similar to this. He’s even using a GMT 400 chassis (Tahoe). But we’re probably going to take it in 2 stages. I’d love to just go for broke but it’s his project so it’s his decision.

First do a mild all motor LY6 build. They already have great LS3 style heads, so we’re going to swap on the LS3 intake, headers, and a cam. With the right cam and good tuning you can make over 500HP at the crank and have excellent drivability.

After he gets bored with that, we will probably redo it for a “mild” turbo setup. We will do head gaskets and studs (if we don’t do that in phase I), maybe even pistons and rings. And we’ll go to a less aggressive, more turbo friendly cam, maybe the LS9 cam since they are pretty cheap. Shooting for 800HP on pump gas, maybe 1,000HP on E85.

Oh, this also reminded me. Despite Hot Rods success, one thing I’ve heard is that the LS rod bolts aren’t great and will stretch after repeated hammering with boost. Apparently ARP rod bolts are, good, cheap insurance.

Smallbear wants a modern Syclone, local Maple Leafs spammer > Snuze: Needs another Swede
09/03/2015 at 13:48

For $150 it's not worth taking the chance, really.