ATTN: SBC users

crzyone · Post by **crzyone** » Thu Aug 17, 2006 12:30 am

Aaron wrote:So find me a 302 that revs past my 383. If you do, fine. I'll find an even bigger motor that revs farther.

You can find a cam, heads, and intake to rev a large bore/stroke SBC to any RPM you want.

Also weird, I have a 2.8l in my 88GT. It has short stroke, so it must be a high revver. YAH. But my 3.4 DOHC in my other 88GT has long stroke, so it can't rev for shit.

Odd, I could have sworn I saw the tach nail 7100 this afternoon. My 2.8l can't do that.

You are a fucking idiot. It took me quite a while to see it, but you are. You think you know absolutly everything don't you?

Short stroke and large bore > Long stroke. 1 main reason- TORQUE!! A motor that can develop good hp and not have as much torque is what you want in a fiero which has a weak transmission. You do NOT want a motor that develops a ton of torque.

Get your head out of the clouds and THINK for once.

I would take a chevy 302 over a 383 any day of the week.
1- Its neat because they are rare.
2- It makes a ton of hp and revs to the moon
3- Less trani and axel snapping torque

:flipa:

Aaron · Post by **Aaron** » Thu Aug 17, 2006 8:44 am

Let's try to see this so you might understand. I KNOW the 302 can rev higher, I just don't see the point when you can get a 383 to rev to the moon (I've seen 10k a bunch of times).

Compare the 2.8 and 3.4 DOHC. The 3.4 has a longer stroke, which should imhibit revving. The 2.8 has a shorter stroke, which by all your definitions should rev higher. The difference is head flow. Our heads are much better, that allows us to make more horsepower and torque, and to rev higher. It is the same story with the SBC. If you want to rev high(er), put a bigger cam and better heads in.

The Dark Side of Will · Thu Aug 17, 2006 12:44 pm

My moderation policy is to remove inflamatory material, trolling, spam, etc.
As long as the topic sticks to technical material, I see no need to moderate.

If anyone thinks that Aaron is wrong, then pony up the tech data to show why.

In typical know-it-all fashion, Aaron isn't outright incorrect... he's just correct is his own little idealized world that isn't impacted by any practical considerations.

383 vs 302...
Calculate the rod stress for both engines and you'll find that a 302 can turn over 7500 RPM with the same rod stress as a 383 at 6000 RPM. This means that you can toss a 302 together on the cheap and still wind it out. You can't do this with a 383.

Yeah, a 383 makes a lot of torque... which doesn't get to the ground well when you rip all the teeth off 1st or 2nd gear...

The 383's torque band doesn't work well with short gears in a light car. Since our transmission choices are limited, we need to match the combination well however we can.

What did I miss?

Aaron · Post by **Aaron** » Thu Aug 17, 2006 12:59 pm

The Dark Side of Will wrote: 383 vs 302...
Calculate the rod stress for both engines and you'll find that a 302 can turn over 7500 RPM with the same rod stress as a 383 at 6000 RPM. This means that you can toss a 302 together on the cheap and still wind it out. You can't do this with a 383.

You are right, and I said that myself. Let me quote it...

Aaron wrote: There is no point to use small cubes in a SBC, unless you are limited by class or budget.

Obviously, and in typical Fiero fashion, he is restricted by budget. High RPM, high HP 383s don't come cheap.

Yeah, a 383 makes a lot of torque... which doesn't get to the ground well when you rip all the teeth off 1st or 2nd gear...

The 383's torque band doesn't work well with short gears in a light car. Since our transmission choices are limited, we need to match the combination well however we can.

What did I miss?

To say "The 383's torque band" is blatantly incorrect. A 383 can be built to have the same torque band as a 350 or 302, just more of it. Again, budget allowing. They do make a lot of torque, despite high end tuning, that's why they are so popular, and not so popular in Fieros.

So you are pretty much saying, that we need to build engines to not make a lot of power and torque, contrary to every other engine builder in the world. Go Fiero innovation, less power for the same price!

The Dark Side of Will · Thu Aug 17, 2006 1:57 pm

<sigh>

Aaron, stop pushing your viewpoint on everyone else.

The point is not that a 383 can make a lot of power.

nfswift · Post by **nfswift** » Thu Aug 17, 2006 2:34 pm

Oh crap. This thread turned into a giant debate, from which I have also learned what I needed to know.

Firstly just shoot me now, I need to learn more about the car before I start this swapping shit. Maybe I'll just find a TDC on the cheap and do the simplest swap before moving along to the shitstorm difficult ones...

Basically I'm either looking at a VERY expensive process of getting the V-8 tranny and the Fiero transaxle to play nice (and hoping the torque doesn't fuck it up), or breaking any other transmission after two launches, if I get it to mount to the engine properly that is.

I wish it was easier to mount it transverse-like so I could just use a different axle and the 12 bolt posi-traction diff out of the V-8 donor...

I think I'd rather do up a 3800II or a TDC in the meantime, something that I can get a manual tranny with. The L67 strikes my fancy, but sounds pricey and difficult... the TDC sounds dirt cheap and simple...

What's a guy to do, I just wanna go fast hah hah...

Edit: The 302 sounds neat as well, I'd just prefer not to have to mess with the bottom end at all... what's so different about the 302 than a Chevy 305 anyway?

The Dark Side of Will · Thu Aug 17, 2006 2:43 pm

The transmissions aren't made of tissue paper... Well... the GM Isuzus are, but the Getrag and the Muncie usually last a good while behind a V8.

You just have to remember that you're dealing with a transmission designed for 200 ftlbs of torque and putting 300+ through it. Solid mounting is bad. Slicks are bad. Clutch drops are bad.
You're going to have the same problems with high power no matter which engine you chose... just chose the engine you like.

I would advise picking whichever limited slip device you can afford:
www.phantomgrip.com
www.gr8grip.com
www.engineered.net

donk_316 · Post by **donk_316** » Thu Aug 17, 2006 2:51 pm

fast and easy? go 3.4L pushrod with fiero V6 injection... go vroom with H272 cam and exhaust.

I did one and it was very cool. I then swapped to a TDC to go turbo... now the car belongs to "mrsleeve" on this board.

The Dark Side of Will · Thu Aug 17, 2006 2:53 pm

well... easy at least.

Oh... you meant that the swap was fast, not that the car was fast afterward.

donk_316 · Post by **donk_316** » Thu Aug 17, 2006 2:57 pm

when it was carbd the car pulled a 13.7... not bad for a "shitty" 3.4L pushrod.

When i swapped to EFI... the car GAINED midrange but lost torque off the line and was rev limited by the intake... Still a fun car @ 200hp!

Come back to reality! not every fiero NEEDS 300hp to be FUN!

The Dark Side of Will · Thu Aug 17, 2006 2:59 pm

I understand, but it's difficult to compare a well-done 3.4 to a well done 5.7...

Now a well done 3.4 does compare favorably to a poorly done 5.7...

nfswift · Post by **nfswift** » Thu Aug 17, 2006 3:54 pm

The 350 sounds like a bit of a piglet to get working in a hurry, so the TDC looks like a better choice at this point.

The 94-97 LQ1 made 215 hp with it's sequential fuel injection... that doesn't sound like much of a slouch to me. Do you lose a bit of that power using the Fiero fuel injection?

The L67 still sounds better, but a lot pricier I'm sure for a series II, and more difficult to get working with the harness and fuel delivery.

donk_316 · Post by **donk_316** » Thu Aug 17, 2006 4:04 pm

Im talking 3.4L PUSHROD from a Camaro.

NOT 3.4L DOHC

crzyone · Post by **crzyone** » Thu Aug 17, 2006 4:22 pm

I've been in a SBC fiero, it was the fastest car I've ever been in. It was a 406ci built engine with a Holley Stealth Ram FI system. It put me back in the seat violently and could powerslide well into 3rd gear with absolutly no problem. This was also bolted to the fiero getrag transmission.

The owner of this car said his car dynod at around 380hp, and I can imagine it probibly had over 450lb/ft of torque. It was an insane ride.

If you want to build a sbc fiero, then do it first. If you buy Archies kit then you basically only need to follow the directions on his install tape, I imagine its fairly straight forward. You can start with a mild 350 and then if you want more power, its an easy motor to upgrade.

whipped · Post by **whipped** » Thu Aug 17, 2006 4:27 pm

crzyone wrote: The owner of this car said his car dynod at around 380hp, and I can imagine it probibly had over 450lb/ft of torque. It was an insane ride.

Nice! hehehe

The Dark Side of Will · Thu Aug 17, 2006 4:37 pm

crzyone wrote:If you buy Archies kit then you basically only need to follow the directions on his install tape, I imagine its fairly straight forward.

Except that he solid mounts the engine and soft mounts the transmission, which is even worse for transmission longevity than solid mounting everything.

The Dark Side of Will · Thu Aug 17, 2006 4:40 pm

crzyone wrote:I've been in a SBC fiero, it was the fastest car I've ever been in. It was a 406ci built engine with a Holley Stealth Ram FI system. It put me back in the seat violently and could powerslide well into 3rd gear with absolutly no problem.

And you're taking a Skyline over that?

MNFatz · Post by **MNFatz** » Thu Aug 17, 2006 6:20 pm

The Dark Side of Will wrote:
crzyone wrote:If you buy Archies kit then you basically only need to follow the directions on his install tape, I imagine its fairly straight forward.
Except that he solid mounts the engine and soft mounts the transmission, which is even worse for transmission longevity than solid mounting everything.

No, he solid mounts everything done in his shop. He does list the rubber trans mounts/solid motor mount in the instructions though. I can't believe anyone would actually do it.

The answer I got on the solid mounting was drivetrain deflection (don't shoot the messenger). He experienced more trans failures when everything was mounted on poly; the thought being the torque load shifting directions caused more final drive failures than the solid mounting.

nfswift--welcome to the forum by the way. You've already met the forum idiot--just ignore him; he doesn't know what he's talking about.

The Dark Side of Will · Thu Aug 17, 2006 6:23 pm

If he's seeing more failures on poly, that just means his mount system has too much FLEX and not enough COMPLIANCE.

Meaning that his stuff can flop around, while a decent mount setup allows the engine to move but creates a restoring force proportional to the deflection. Thus the mounting serves as a cushion against shock load without allowing the powertrain to build any angular momentum that would damage the transmission.

S8n · Post by **S8n** » Thu Aug 17, 2006 7:07 pm

The Dark Side of Will wrote: Solid mounting is bad. Slicks are bad. Clutch drops are bad.

You're just out to ruin my fun, aren't you Will? My engine/trans is solid mounted, might upgrade to delrin depending on a few things, FYI.