Other GM engines

[Atilla the Fun]

You all know I'm a die-hard Chevy V8 addict, but with curiousity, I spent time looking at Wikipedia's list of other GM engines. I started with the Cad 4.9, and I still think it has no place in any Fiero. It's not well suited to centrifugal supercharging, because of the stupid intake manifolds and iron heads. And for those of you not at high elevation, it has too much compression. On to the more modern V6s. Upon learning that the '08-'09 G8's 3.6L gives 248 ft-lbs at 2100 rpm, I'm willing to consider it might be able to equal a stock 4.3L V6-90, but the 4.3 can do it on 85 octane, where the 3.6L needs 94 octane. On the other hand, it does make power to 6300 rpm, and the best 4.3 isn't going there without a custom fabricated short-runner intake manifold and a bigger cam, and then it no longer makes the low rpm torque. So now I'm ready to take one of these for a test drive, but noone in Utah has a 3.6L Fiero. It being 10.3:1, with forged crank ( with rolled fillets ) and forged rods, and NOT direct injected, ( easier to go to bigger injectors ) means boost is very doable up here, but an L67 is still cheaper and simpler, especially the electronics.
The shortstar is rare, but should be much more durable under high boost than the Twin Dual Cam 3.4L. The 9.3:1 is begging for boost, at least up here. The LA3 is even more rare, but would be a great choice at higher elevations without boost, because of the 10.8:1. And with only 3.2L, should get amazing MPG. Lastly, the 3.9L. As near as I can tell from such limited research, it really is inferior to both the 3.6L and the 4.3L, and still more expensive and complicated to get running than the L67, though it should be lighter than all but the 3.6.
What I'm concluding is that when the laws finally get crazy stupid, and they will, it looks like I will be going to a heavily modified 3.6L. Hopefully by then GM will have taken advantage of this block's potential to go to 4.0L. The hot ticket looks to be a 4.0L short block under the G8 top end, but with aftermarket forged pistons, then add boost. That should be 550 real HP, and 500 ft-lbs from 2500-6000 rpm.
But still, not as low buck as doing it with a Chevy V8. Even if you figuer in the difference in mpg, which is more than offset by the purchase prices and the costs of all the electronics.

[jelly2m81]

The more I read and think about the cadillac 4.9, as much as I will never install one in one of my cars I do think dollar for dollar it's the best V8 Fiero swap compared to a SBC chevy.

It's a cheap motor and simple to install and wire. It is not fast, but honestly, 99% of SBC Fiero's aren't either. Why go through the hassle and cost of an adapter plate and the extra weight when it will underperform. Sure a SBC will be faster than your average 4.9L, but for what you spend dollarwise to have dissapoining performance, it makes no sense.

[Atilla the Fun]

First, a Pick N Pull Vortec 350 is not a penny more than a Pick N Pull 4.9, and while you are at PNP trying to choose, you can either go find a flywheel from a 305 pickup and bolt it to your 350 instead of the flexplate, ( to turn down like Fieroguru ) or you can yank the caddy's wiring harness and computer. With the 350, go grab an older QJet and an HEI dizzy, but take NO intake manifold. Pull the 350 damper off, and loosely bolt one from a 3.1L ( just like Fieroguru ). Now, when you go to pay, the Caddy is $50 more because of the harness and computer. Then, you have to come up with a flywheel for the Cad, since GM never produced any direct fits. So now the SBC is cheaper by $150-$250, depending on what you did for a Cad flywheel. To be fair to the Caddy, the 350 needs a starter, so spend $10 at PNP for a Nissan Maxima starter ( again, like Fieroguru ). With the cad, no adapter plate, but with the 350, you'll need a sheet of steel, 1/4" thick, 18" x 24", so figure $30 tops. The 350 is still cheaper. Now, you mentioned weight. I must concede that point, the 4.9 is an aluminum block. So, now you either have a Cad with 200 hp, or a Vortec 350 with 255 HP, assuming stock exhaust manifolds. Next, the Cad computer needs some programming so it doesn't stall at every stoplight. Assuming you can't DIY, this will cost more than an intake manifold for the Vortec heads. Now, both engines came with 2 exhaust manifolds, a water pump each, an alternator each, and the Cad came with a bracket for the Alt. But for the 350, the big center hole you cut out of the plate can be cut into an alt bracket.
In the end, the cost comes out virtually equal, with the Vortec 350 making more HP, revving way higher, and being a cam away from 300 horses. the cad won't get to 255 HP even with a cam swap. And even then, it still won't pull to 5500 rpm like the Vortec 350 will. The Cad is not a sporting engine, the Vortec 350 is THE very definition, a global legend. You can't even port the Cad heads to equal the unported Vortec 350 heads.
If you can't yet see the Chevy supremacy, then you deserve the losing Caddy.

[jelly2m81]

If you can't yet see the Chevy supremacy, then you deserve the losing Caddy.

Welcome to 5 years ago, the results are in, SBC's Fiero's perform sub-par.

4.9 method : Cheap junkyard engine, easy install. Result. Slow car

Your method: parts from 6 different engines / cars. Old worn out carburator. Extra work mashing that shit together. By an adapter plate or still spend money having one correctly made. Result: cobbled together slow car.


So, both cars are slow and shit boxes, difference is one is easier and cheaper.


Wow! carburator?

[Blue Shift]

Stock for stock, the 3.6 DOHC VVT will kick seven shades of shit out of any other GM V6 ever made, even the almighty GNX 3.8L and Sy/Ty 4.3L (they didn't make 300+HP in stock form, either). When it comes to parts and modding, that's another matter though with the wide availability in a popular performance car now (Camaro), it's a matter of time until a variety of performance parts become available. Saab also offered a turbocharged, conventional port injected version of 2.8L displacement as well, and mated to the F40 6 speed transaxle - could make for a kick ass drop in drivetrain, and a possible swap out to a 3.6L longblock for more cubes. I'm positive that I read an article on GM Racing's website at one point, where they claimed 1750HP in FWD drag form with the STOCK block, crank, and head castings... Crazy shit.

Anyways yeah, the 4.9 is an epic POS. I bet the higher compression is to try to fight the lack of good cylinder fill from those tiny ports! If somebody is going to halfass a 200HP V8 Fiero, at least you don't need an adaptor plate, a kit, or cutting a hole in the wheel well if you go the V8A route... And still get that V8 wow, sound, and MPG... Also in CA, you have a factory engineered drivetrain w/transmission that'll pass BAR recertification if you do it right. Good luck getting anything with an adaptor plate through!

[The Dark Side of Will]

The DI Turbo Ecotec has shown that the direct injectors can supply over 75 HP each. I'm not sure what their limits actually are. In a V6 that's obviously at least 450 HP.

Also note that all of GM's DI engines also have port injected variants, so the port injection manifold can be bolted to a DI engine for dual injection if the fuel needs are high enough. Engine management won't be cheap, though.

I have a couple of other things to get done when I get back, but my first choice for a new powertrain to play with will be the DI Turbo Ecotec with the hybrid accessory drive and battery pack from a Saturn. After that I want to mess with 3.6 DI + 6 speed. Then I'd like to convert a VVT Northstar to DI.

[Atilla the Fun]

If you can't yet see the Chevy supremacy, then you deserve the losing Caddy.

Welcome to 5 years ago, the results are in, SBC's Fiero's perform sub-par.

Welcome to now: other people's SBC Fieros are still performing sub-par. I've been angry about this for a while now, and I am started on proving it's the fault of the stupid apes who put the combos together poorly then drive them wrong, not the SBC itself. And even when I'm done, there will still be only one SBC Fiero not below par, but it's enough to prove the point, and it'll be fun to drive.
You both have missed the primary and secondary points of this thread. As to the Cad being the inferior engine design to the SBC, the fact of it not needing an adapter plate or a custom alt bracket or reworked crank pulley or starter situation can never offset it's inferiority to the Vortec 350. And as I just illustrated, there is no build cost advantage to it. The 350 really is worth the little extra labor. If you disagree, bring your 4.9 Fiero and all your receipts to Rocky Mountain Raceway this November.
You can't make a valid argument against the torque of the SBC when so many boosted Fieros are successfully running over 500 rwtq with 282s.
Now, could we please stay on topic?

[Atilla the Fun]

Stock for stock, the 3.6 DOHC VVT will kick seven shades of shit out of any other GM V6 ever made, even the almighty GNX 3.8L and Sy/Ty 4.3L (they didn't make 300+HP in stock form, either). When it comes to parts and modding, that's another matter though with the wide availability in a popular performance car now (Camaro), it's a matter of time until a variety of performance parts become available. Saab also offered a turbocharged, conventional port injected version of 2.8L displacement as well, and mated to the F40 6 speed transaxle - could make for a kick ass drop in drivetrain, and a possible swap out to a 3.6L longblock for more cubes. I'm positive that I read an article on GM Racing's website at one point, where they claimed 1750HP in FWD drag form with the STOCK block, crank, and head castings... Crazy shit.

Anyways yeah, the 4.9 is an epic POS. I bet the higher compression is to try to fight the lack of good cylinder fill from those tiny ports! If somebody is going to halfass a 200HP V8 Fiero, at least you don't need an adaptor plate, a kit, or cutting a hole in the wheel well if you go the V8A route... And still get that V8 wow, sound, and MPG... Also in CA, you have a factory engineered drivetrain w/transmission that'll pass BAR recertification if you do it right. Good luck getting anything with an adaptor plate through!

Most 3.6s aren't the 304 hp version, most are under 265 HP. the Sy/Ty had 280 hp and 360 tq, and alot more average HP due to the high TQ. I would bet my money on a Sy/Ty-engined Fiero over a comparable 3.6-engined Fiero.
Passing adapted combos has been done successfully. The 350 was used with a QJet in a passenger car application as late as 1988, albeit with an automatic trans. It was the Police Caprice. Thank you for staying on topic.

[Atilla the Fun]

The DI Turbo Ecotec has shown that the direct injectors can supply over 75 HP each. I'm not sure what their limits actually are. In a V6 that's obviously at least 450 HP.

Also note that all of GM's DI engines also have port injected variants, so the port injection manifold can be bolted to a DI engine for dual injection if the fuel needs are high enough. Engine management won't be cheap, though.

I have a couple of other things to get done when I get back, but my first choice for a new powertrain to play with will be the DI Turbo Ecotec with the hybrid accessory drive and battery pack from a Saturn. After that I want to mess with 3.6 DI + 6 speed. Then I'd like to convert a VVT Northstar to DI.

I did not know that. Thank you for the info.

[The Dark Side of Will]

You can't make a valid argument against the torque of the SBC when so many boosted Fieros are successfully running over 500 rwtq with 282s.
Now, could we please stay on topic?

Exactly how many boosted Fieros are running over 500 rwtq through a 282?

That's a common thing to hear from V8 nutswingers... They talk about the huge number of V8 Fieros built... I'd be surprised if that number were more than 2000. There are more new Ferraris on the road each year than existing V8 Fieros.

[Atilla the Fun]

I'm very sure I've heard of at least 3 of them. One of which is a white pace car with a centrifugal-blown SBC, one of which is a turbo 3800, and one I think being a turbo Twin Dual Cam 3.4

[Emc209i]

Also note that all of GM's DI engines also have port injected variants, so the port injection manifold can be bolted to a DI engine for dual injection if the fuel needs are high enough. Engine management won't be cheap, though.

Sounds like a recipe for pre detonation, given the incredibly high compression ration of the direct injected engines (with pump gas in mind). A secondary fuel pump would also be required to supply the manifold injectors with a lesser pressure suitable for their operation.

[jelly2m81]

Idiot, I do not have a 4.9 Fiero and I will never have. I believe it's as pointless a swap as a SBC.

Unlike you, I am not a dreamer, I have already built several SBC Fiero's.

[Atilla the Fun]

Also note that all of GM's DI engines also have port injected variants, so the port injection manifold can be bolted to a DI engine for dual injection if the fuel needs are high enough. Engine management won't be cheap, though.

Sounds like a recipe for pre detonation, given the incredibly high compression ration of the direct injected engines (with pump gas in mind). A secondary fuel pump would also be required to supply the manifold injectors with a lesser pressure suitable for their operation.

Since you'd need forged pistons anyway, may as well order them with enough dish to get the compression ratio down.

[Atilla the Fun]

Idiot, I do not have a 4.9 Fiero and I will never have. I believe it's as pointless a swap as a SBC.

Unlike you, I am not a dreamer, I have already built several SBC Fiero's.

You start by claiming that SBC Fieros perform sub-par, and now you say you built several? Look at what you're saying about yourself. It says you build sub-par -performing SBC Fieros.
Unlike you, I am a real racer, I know what any given SBC WILL do in a 3000 pound car, wherever the transmission is located. I'm not required to drop everything else in my life and immediately devote ALL my time and money into having my SBC Fiero build done by the time the local dragstrip opens for the summer. I can take what time I need to prove my point. Ten second time slips are coming. I don't much care if it's this August, or next July. I didn't rush to get my 355-powered '88 IROC-Z into the tens, at 3500 pounds, no less, and I'm not gonna rush this.
You are allowed to believe differently from me, you are allowed to say I'm mistaken. But you'll never prove something that isn't so. You just prove it's you who is the dreamer. You also prove you're petty and closed minded. Now, stop taking my thread off topic. If you want to start your own "Cad vs SBC" thread, go for it. Besides, claiming you've never done the cad and never will, but you've done several SBCs, proves you did believe the same as me, so why argue to the contrary? Don't answer that here, just go away, since you can't stay on topic.

[Jinxmutt]

You start by claiming that SBC Fieros perform sub-par, and now you say you built several? Look at what you're saying about yourself. It says you build sub-par -performing SBC Fieros.

When a customer offers to hand you a check to build him a fiero, you put whatever damn engine in it he wants...

[The Dark Side of Will]

Also note that all of GM's DI engines also have port injected variants, so the port injection manifold can be bolted to a DI engine for dual injection if the fuel needs are high enough. Engine management won't be cheap, though.

Sounds like a recipe for pre detonation, given the incredibly high compression ration of the direct injected engines (with pump gas in mind). A secondary fuel pump would also be required to supply the manifold injectors with a lesser pressure suitable for their operation.

Since you'd need forged pistons anyway, may as well order them with enough dish to get the compression ratio down.

The boosted Ecotec runs 9:1 compression. The N/A applications run 11.3-11.7 on 87 octane. GM doesn't have any premium fuel only DI engines. The Audi FSi engines run 12.9:1 on premium fuel.

The shape of the piston crown is extremely important in a DI engine. Just going with a dished piston won't cut the mustard.

http://www.hotrod.com/techarticles/engi ... index.html
http://www.hotrod.com/techarticles/engi ... to_07.html

[befarrer]

Basically the same as a diesel, combustion chambers are in the pistons, not the head.

[The Dark Side of Will]

Not really... GDI engines need the piston shape because they can function in either stratified charge or homogeneous charge mode. Mixture motion is very important.

http://autospeed.com/cms/title_Direct-P ... ticle.html

Also, the only reason that a dual injection intake tract would be required is to have enough fuel for extremely high boost. If you're running extremely high boost, you won't be running 11+ compression.

[Blue Shift]

My next Atilla-esque engine swap project is going to be a 2.3L Q4 HO/282 drivetrain I have sitting around. Compared to my DOHC car, I kinda wanted to build something smaller, lighter, and more nimble. 2 more MPG and double the crank HP of the duke are welcome outcomes as well. I know they're not the shit anyore, and an Ecotec would be awesome, but the extra complexity, cost, and CA BAR recert requirements don't interest me. Plus, with the stock "2M4" decal on the decklid, and an obvious 4 cylinder exhaust note, it'd be really humiliating to be beaten by!

On the side, I'll probably build up a long block out of a later year block (possibly even a 2.4 block), with custom pistons, Eagle 4340 H beams, and maaaayyybe a forged crank if I can find one. Bryson did 400 HP on what looked like modded stock rods with ARP bolts that later appeared to be defective. 300 HP would be fine, 400 would be as far as I would logically want to go. It might also be a good candidate for that Holset HE351VE... I could easily run it at higher pressure than I could have boosted the DOHC to, and be deeper into the max efficiency island of the compressor.

Anyways, but yeah.