Messages

1

General Fiero Discussion / Re: Another F23 5 spd conversion

« on: December 21, 2017, 06:08:45 am »

Thanks. For the form, I used thin fanfold insulation hot glued together and waxed. I setup a few layers on the outside, removed the form, added a couple layers to the inside, trimmed to fit the decklid, then glassed it into the deck. It is just rustoleum aerosol spray paint that matched really well.


I removed the firewall wiring bushings to get rid of all the extra wiring I didn't need. A pot of hot water to soften the sealant helps.

2

General Fiero Discussion / Re: Another F23 5 spd conversion

« on: December 19, 2017, 05:57:54 pm »

The distributor cover is an aftermarket ignition coil that sits in the cap.
Those are the shifter cables with "fire sleeve" to protect them from exhaust heat. I have sleeving on the oil lines too.
I forgot a pic of the decklid bump.

3

General Fiero Discussion / Re: Another F23 5 spd conversion

« on: December 18, 2017, 06:21:40 pm »

Welded a tab to the alt brkt so I could attach a rain guard/heat shield. The shield also picks up a third bolt on the block and is not attached to the alternator so there is an air gap and it does not affect belt adjustment.


Fabbed adjustable throttle bracket to work with the fiero's long exposed cable end that normally wraps around a throttle body quadrant. This pic was before I found I needed to boxed the top where the cable boss fits through.

Installed pic.

Clearance notch I spoke about before. Eventually i will repair the inner well.


Moved tank for better access. Also replaced lines that were severely corroded/split from being under the battery.

This piece goes between the shifter and the front attachment points on the arm rest. I needed a repair and did not want to rebuild the whole center console. I probably will eventually.

I made a deck lid prop also but didn't take any pics. My deck lid springs broke long ago.

4

General Fiero Discussion / Re: Another F23 5 spd conversion

« on: December 18, 2017, 05:41:52 pm »

I put it back together, added a speedo calibrator, new brake hoses, made a middle section of the center console skeleton out of metal since mine was a mess, cut off the rear deck lid bump and made another, rebuilt the alternator, and moved the fuel tank vapor separator from the passenger side fender well to under the left rear deck grate. I then had a wiring issue that I didn't have time to resolve before working on other things and have not been back to it, but I will eventually. That was around the end of October. I'll put together some pics.

5

General Fiero Discussion / Re: Another F23 5 spd conversion

« on: August 28, 2017, 02:49:00 pm »

Vacuum bled the htob and cleaned up the frame rail to remove the left over pieces of trans mount brackets and beveled the corner for more clearance. Compare to previous photo of rail.

6

General Fiero Discussion / Re: Another F23 5 spd conversion

« on: August 28, 2017, 11:48:29 am »

The thick black spacer between the engine and the f23 is the adapter that doubles as the starter mount. The original 4.3 starter location interferes with the passenger side axle.

The relocation interferes with the oil filter and sometimes the exhaust depending on the manifold used.
I’ve had 3 oil filter adapters, 3 different manifolds, and 2 different starters over the years. No failures, just continuing improvement.

The 4.3 is also a common marine engine and another source for carbureted intake manifolds.

The ecm provided the timing curve to the electronic distributor instead of advance weights and vacuum advance. The distributor I have is a basic sbc hei type with weights and vacuum but a six point pickup instead of the 8 point pickup for an sbc. It has one spade terminal for the ignition power and one for the tachometer output.


The adjustable engine support worked great. Just a few turns set it to where I needed it to pull the trans.

While I have it out, there is an area on the subframe that I would like more clearance from. It isn’t necessary but since it is easy to get to….

HTOB/HRB MEASUREMENTS

A few posts back, I mentioned that I tested the clutch system and found 0.480-490” of travel at the HTOB with one full stroke of the fiero master. This is the minimum that the HTOB must be compressed from the end of its travel to ensure it cannot over extend (To compress more than this can result in reduced clutch life, since the pp fingers move toward the trans as the clutch wears and can unload the clutch if shimmed too much).

One way to do this is to make sure the engine side protrudes far enough at the pp fingers to compress the HTOB this far. For tolerances, I chose to use 0.500” as the minimum cushion.

Fully extended, I measured 1.890”. 1.890+0.500 = 2.390” as the minimum distance from the bell mating flange to the HTOB.

For the engine side the pp finger height needs to be a minimum of 2.390” from the bell mating surface with a new clutch.

Here is a comparison of a replacement pp and clutch for a 2002 cavalier and the standard fiero pp used in most applications through the 90s and the aftermarket ceramic clutch I’m using.


The ceramic clutch is 0.320” thick at the facings as is the cavalier clutch with the marcel spring squeezed.

Installed, the standard fiero pp puts the fingers at 2.300“ from the bell housing mating surface on the block adapter and would require a $5 0.89” crank shim if the clutch is new which is slightly less than my cushion minimum of 0.500 but greater than the actual measurements of 0.480-490”. It should be fine.

The cavalier pp puts the fingers at 0.135” further (than the standard fiero pp) from the block adapter at 2.435”, no shimming required.

So now I just need to bench bleed the HTOB and put it back together.

7

General Fiero Discussion / Re: 60-degree V6?

« on: August 28, 2017, 06:59:38 am »

How long did the swap originally take you?

I guess my memories are wordy.  My point was that I remember the advent of the internet, and the change from before to after, as well as the changes in computers and how they have impacted our lives.

I don’t recall how long it took, but I was in no hurry and enjoy problem solving. The initial installation to driveable wasn’t long but it took much longer to sort out the issues of exhaust to starter clearance, starter to oil filter adapter clearance, rain and water corroding the alternator internally due to its location, air cleaner clearance, coolant routing, access for maintenance, and a solution for controlling the torque reaction of the engine. Some of these issues were unique to the v6 so the sbc swappers didn’t have them when using the kit but they had solid mounting and chassis cutting requirements for the longer engine.

I found some weights I’d measured with the 4.3 at 380 lbs, a v6-60 at 345 lbs and a 4.9 about the same as the v6-60. Sbcs are around 500 lbs. 
Thanks Raydar. I’d forgotten about those other engines and completely missed GTX’s post.

8

General Fiero Discussion / Re: 60-degree V6?

« on: August 27, 2017, 06:55:41 pm »

You remember a lot!

The intake is a stock 1985 astrovan iron intake for a quadrajet 4 barrel carburetor. As you can see it is very tall.


Here is the intake I described before that will be going on eventually.

Here is some more info on the engine and a basic build up:
http://www.superchevy.com/how-to/113_0208_chevy_43l_262ci_v6_engine_build/

9

General Fiero Discussion / Re: Another F23 5 spd conversion

« on: August 27, 2017, 03:12:19 pm »

Ok, my process is to use my wheel chocks on both front wheels, jack the rear center of the subframe and install jackstand under the corners, then install the lift bracket, move the jack stands to the lift, install the trolley and engine support tube then and drop the subframe, lift the lift to full height which is about 40 inches from the ground to the bottom of the trunk, and roll the trolley out. Plenty of room. Another benefit is the engine cover can be closed fully. 




 






My $19 jack stands came in. I added 20 inches to the height. Now I just need to finish this one and build it's twin, then i can get back to the f23 thing.

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General Fiero Discussion / Re: 60-degree V6?

« on: August 27, 2017, 02:56:34 pm »

well that raises another question,  90Deg. OR 60deg. and will that bolt in the same as a 3.4 from a camero ? and do any FWD  GM Engines just bolt in with maybe a starter re location.  O K 3 questions.

Only the 90 degree 4.9 v8 and 3.8 v6 have the metric v6-60 pattern as far as I know. The fiero is a fwd drivetrain from a chevy citation and most any gm fwd v6 up to the mid-90s I believe will swap. On a related note, S10 transmissions and bellhousings are often used to convert the fwd v6s to rwd for use in MGs and Triumphs.

For a manual, unless you want a custom flywheel, I'd stick with a v6-60 such as a 3400 from a mid 90s fwd van or just rebuild the 2.8 with 3.1 parts for more displacement but I don't remember all the details but can look it up if you are interested.

11

General Fiero Discussion / Re: 60-degree V6?

« on: August 27, 2017, 02:44:14 pm »

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.

It isn't that simple. Engines have an rpm range where BSFC is lowest. This is typically around the torque peak rpm. Operation outside this area burns more fuel. If the engine is modified to improve power at higher rpms, this can increase the BSFC at the torque peak.

Forced induction engines have a higher bsfc than normally aspirated and diesels have a lower bsfc than na.

The point is, for a specific power and torque output, it is best to use an engine that provides close to that in a stock form if minimum bsfc is desired. There are a lot of ways to reach a number like 30 mpg and I'm sure F85gtron could do that. It is all a compromise.

Having said all that, remember this was nearly 20 years ago. Back then, there wasn't much information online for car guys. The basic browser and search engine was only a few years old. Before that you had to find boards. When broswer came out I thought, great, now everybody is going to be online . My point is it was not common knowledge that the 3800 and 4.9 would swap. Had I known, I would have just used one of those and saved a lot of money so here I am, making the most of it.

12

General Fiero Discussion / Re: 60-degree V6?

« on: August 27, 2017, 02:28:27 pm »

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.

Power to weight ratio and torque multiplication through gearing are major factors in what makes a vehicle seem fast or slow. Trucks usually have a wide variety of axle ratios to choose from that make a night and day difference in performance and mpg.

13

General Fiero Discussion / Re: 60-degree V6?

« on: August 27, 2017, 06:54:43 am »

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.

14

General Fiero Discussion / Re: 60-degree V6?

« on: August 26, 2017, 03:23:15 pm »

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.

15

General Fiero Discussion / Re: Delivered 2 me, 2-day

« on: August 26, 2017, 08:54:42 am »

That is a plate bracket made for something else, modified to work on the fiero.

I found some photos of the original bracket. The originals were unique being very deep to reach the back edge of the opening and a cup center made to fit the fiero curvature. The bracket you bought, modified to work is unusual also since most brackets available these days are not made that deep. Not perfect but at least it is being offered.

I’m guessing your bracket came with large washers to go behind the abs strips so they don’t crack and nylock nuts so it doesn’t have to be very tight yet won’t come loose. If not, you might want to go to the hardware store and buy some nylocks and fender washers or replace the abs. Nobody is going to see it isn't perfect and the holes are not so close to the edge to be a problem.

I doubt there are enough aero nose fiero owners that live where front plates are required or simply want a front plate to justify a production run on original style brackets.

One way to make these is to use 1/8x1 steel strip with a scroll bender to follow the perimeter around, then use a standard plastic tag bracket on the front and drill two holes with no welding required. You'd need an aero nose or an original bracket to get it right.