60-degree V6?

[GTRS Fiero]

The short block, undressed?

[fiero4.3L]

Bare block. RWD blocks are 5 lbs heavier.

[GTXVette]

  Man,  we used the archie adapter on my bro's v-8 swap, I had forgotten it was the auto till just now, darn thing was at least 3-4 inch's wide to accommodate the Torque converter?.

 I think a solid 300hp would be about right in the Autocross,  but needs 100 more to be there in the drag portion, and of course nitrous would get that but I am anti juice,  the big v-6 and most v-8's can get that power but mucho Heavy, again too much for the autoX but ok for the drag race. since I'm shooting for next year at this point I may look back at the buick aluminum V-8, they are fairly limited on air flow through the heads though.  I think I could morf a chevy v-8 adapter to do a buick. 

I am not a fan of the lS engines but darn they can make some power, but really in the long run they are as heavy as the LTs and all the Fuel Injection and components are Very pricey,




 

[fiero4.3L]

I was talking about the adapter used for bolting an sbc to a bop transmission or a BOP engine to an sbc transmission.
The v6-60 adapter to one of these uses a pilot bushing to go with it but sbc-bop or bop-sbc just use washers.

I have the same adapter for my 4.3 manual as you used for your brothers 400 sbc auto. I think it is 1.5 inches thick if memory serves and had to be that thick for the crank shaft adapter and hardware to clear (has to be thicker than the heads of the crankshaft bolts plus a 1/4 inch or so under the heads) plus the way Archie mounted the starter. With a specially made flywheel instead of a crank adapter, the block adapter can be much thinner but then you are stuck with a custom flywheel as a wear item. I use a standard fiero flywheel with the 4.3l.

[GTRS Fiero]

So, the 4.3 is basically the SBC 350V8, as far as mounting?  I've had several S-10 Blazers with the 4.3.  Is this basically the same engine?

[fiero4.3L]

Yes.

My 85 4.3 is like the sbc from 1985 and older. Only the 85 4.3 is internally balanced so a stock fiero flywheel can work.
The 86-early 90s are like the 86 and newer sbc with balance weight on the flywheel, a smaller crank flange with one piece rear main seal, etc.

It is possible to make a crank adapter that incorporates the balance weight so that newer 4.3 and sbc could use the stock fiero flywheel but nobody has done that as far as I know of.

[GTRS Fiero]

The 4.3 Vortec was a solid engine in the Blazer, but I think it was a truck engine.

My brother had a light truck with a 5.2, and I had a (much heavier) Formula Firehawk with a 5.7.  He insisted his truck was faster, so we did a little run.  Trucks are light in the rear, so we started at 60MPH.  It wasn't much of a race.  I left mine in 6th, and left him.  I slowed back to 60, and he was still well over 100 when he caught me.  I downshifted to 3rd and punched it...and left my brother like he was sitting still.  So, he insisted his was faster from a stop, because it had lots of torque.  So, we tried from a stop.  I hit 60 in 4.2 seconds, his truck in 7.5 seconds.

I was told that a 5.7 truck engine is not the same as my LT1.  However, a friend of mine has a '79 Chevy truck with a custom 454 from somewhere.  We pulled out into tight highway traffic, one day, and I gave him a start, because I didn't want to overrun him.  We weren't racing; I just didn't want to start going, then have to slow down or worry about oncoming traffic.  Anyway, he was leading the way to the restaurant, so he picked the first gap in traffic, and I picked the next gap.  He truck moved.  That isn't the original engine, however.  He'd had that truck completely rebuilt a few years previously.  There is no way the 350 truck I had would move out like that.

So, is there a difference between a truck engine and a Corvette engine?  Is your 4.3 a truck engine?  How does the 4.3 run in a Fiero?

[GTXVette]

 thats kinda a yes and No answer,one year some would get something that the next year everyone had, I think truck's kept the cast Iron heads when vette's got aluminum heads and when they went to the 1 piece rear main seal one year may have the perimiter valve cover bolts and the next had centerbolt. there were two different Fuel injection set up's /throttle body and tuned port then reverse waterpump rotation and at least two different Ignition systems, Thankfully a lot of stuff could be cloned togeather but then the computers were different. Give me Points and a Carb. I can make that work, you keep the fuel milage.

then they started up the LS Series, where a Car, A truck, and the Vette only shared the long block assy. and everything that bolted to that was different.  I'm So Confused.

 the fiero should be a good learning experince as it's a 60 deg. V-6 (94 camero) aluminim Buick heads, Fuel Injected with a turbocharger,and does have a factory ECM but comes with a Megasquirt controler,  I know nothing about any of it. Lol

[fiero4.3L]

The 4.3 Vortec was a solid engine in the Blazer, but I think it was a truck engine.

My brother had a light truck with a 5.2, and I had a (much heavier) Formula Firehawk with a 5.7.  He insisted his truck was faster, so we did a little run.  Trucks are light in the rear, so we started at 60MPH.  It wasn't much of a race.  I left mine in 6th, and left him.  I slowed back to 60, and he was still well over 100 when he caught me.  I downshifted to 3rd and punched it...and left my brother like he was sitting still.  So, he insisted his was faster from a stop, because it had lots of torque.  So, we tried from a stop.  I hit 60 in 4.2 seconds, his truck in 7.5 seconds.

I was told that a 5.7 truck engine is not the same as my LT1.  However, a friend of mine has a '79 Chevy truck with a custom 454 from somewhere.  We pulled out into tight highway traffic, one day, and I gave him a start, because I didn't want to overrun him.  We weren't racing; I just didn't want to start going, then have to slow down or worry about oncoming traffic.  Anyway, he was leading the way to the restaurant, so he picked the first gap in traffic, and I picked the next gap.  He truck moved.  That isn't the original engine, however.  He'd had that truck completely rebuilt a few years previously.  There is no way the 350 truck I had would move out like that.

So, is there a difference between a truck engine and a Corvette engine?  Is your 4.3 a truck engine?  How does the 4.3 run in a Fiero?

For comparision, here is a test of an LT1 firehawk that puts the 0-60 at 5-6 secs:
http://www.motortrend.com/news/1995-pontiac-firebird-slpfirehawk/
Here is a test of a stock 4wd truck with a 4.3l v6 and a factory turbo that puts the 0-60 at 5-6 secs:
http://www.roadandtrack.com/car-culture/classic-cars/a26217/1992-gmc-typhoon-first-drive-flashback/

It depends on the year model as to what the differences are and how much swaps directly over. An LT1 is drastically different from the traditional sbc.

All 4.3l v6s are truck/van/commercial engines except for a diesel car version in the early 80s.

There have been a handful of 4.3l v6 fieros. The fellow in Alabama with the front engined fiero also shows a 4.3l fiero they built that runs 12s in the qtr. I think fieroguru ran 12s in his also. I don't race. Acceleration is quiet (iron manifolds) and effortless with a lot of short shifting and simple (my engine needs one wire). Economy is 20-30 mpg depending on how I drive. That is what I wanted.

I expect a sorted out 2.8 or 3.8 with a turbo could be much faster.

[GTRS Fiero]

My Firehawk was a '97, but didn't have the decals or ground effects.  Rather than being a TransAm, it was a Formula.  I don't know the torque, but it had 487HP.  The 4.2 seconds was Gateway's time from their test and tune session.  My Formula was very throttle sensitive, so I usually kept traction control on.  To all appearances, my Formula looked like any other.  I got some paperwork with it on the blueprinting and so forth on the engine, as well as some computer stuff, and there were some parts differences.  I know I could break the rear end loose via the throttle at will.  The top speed was well over 182, and the handling was awesome--unless you were making an off-camber turn, in which case it was hell.

But it was no V6.  Somehow, that motor was crammed into the engine compartment.  Sure, there are faster vehicles, but this one was a handful.

[fiero4.3L]

I should elaborate/expand my statement above:

As far as your question about truck and corvette sbc interchange, it depends on the year model as to what the differences are and how much swaps directly over. An LT1 is drastically different from the traditional sbc.

The only thing that MIGHT swap between a 4.3v6 and an lt1 are the oil pump and pickup tube, lifters, pushrods, cam and main bearings, rear main seal, flywheel, harmonic dampener, timing set, pistons, rings, rods, valve springs, retainers, valves, rocker arms and hardware depending on which 4.3 we are talking about.

If memory serves there was also a 4.3L v8 LT1 that came in full size cars around the same time.

[GTRS Fiero]

That's a lot of items that might swap between a 4.3V6 and an LT1.  Wouldn't the list of non-swapping items be shorter?

The Blazer had a 2.8 in it, for some years, and was underpowered.  My Blazers had the 4.3, and were fine.  I had an Impala with a 3.8, and it was peppy, but not a patch on the Impala with the supercharged 3.8 or the Impala SS with the 5.7.  I think the 4.3 is a slower engine than the 3.8, because the Blazer was slow with a 4.3, compared to the Impala with a 3.8.

I guess a 4.3 V8 would have more power strokes per RPM, and some of the Caprices were quick, but I'd prefer the 5.7.  The 5.3 V8 is noticeably slower than the 5.7 Tahoe.

[GTRS Fiero]

I'm just curious of the benefit of the 4.3 in a Fiero.  Not dissing your build, but if the block is heavier, and you're going for MPG, and you don't want performance, couldn't you get better MPG, good performance, and a lighter car with a 3.4 and a good transmission?  I would guess that f85gtron can get 30 MPG.

[GTXVette]

 just to help me decipher this .....was your 3.8 Impala a fwd or rwd ?

[GTRS Fiero]

FWD