3900 versions and configurations for swap use

[Will'sFiero]

The Shaun inspired me with this: http://www.realfierotech.com/viewtop...156968#p156968

So I looked up the PN for the OE engine mount bracket that goes with the LZ4/LZ9 (and LX9?) oil pan.
Here it is:





It *LOOKS LIKE* it might just drop onto the stock Fiero mount with little to no modification. I don't know if it would place the engine higher or lower than the original Fiero bracket/location, though. I guess I'll have to quick jaw jacking and find out.

I did a little more follow up on the mount bracket.

The Buick Rendezvous was available with both the High Value and High Feature V6's in the same year. Both engines used the same rubber mount. The 10216970 bracket shown before is for the pushrod, but there are two different versions of the bracket for the 3.6: 10334474 & 10331334. I have one of each on the way for investigation. Depending on how difficult these are to adapt to the Fiero cradle, this could be a nearly bolt-in swap for a high feature V6.

10216970 2005-2007 3.4/3.5
10334474 2005-2006 AWD 3.6
10331334 2004 AWD 3.6

[Will'sFiero]

The Shaun inspired me with this: http://www.realfierotech.com/viewtop...156968#p156968

So I looked up the PN for the OE engine mount bracket that goes with the LZ4/LZ9 (and LX9?) oil pan.
Here it is:





It *LOOKS LIKE* it might just drop onto the stock Fiero mount with little to no modification. I don't know if it would place the engine higher or lower than the original Fiero bracket/location, though. I guess I'll have to quick jaw jacking and find out.

[Will'sFiero]

Awesome. Thanks!

The holes in the other side of the block are in a different location than the gen1 2.8. IIRC two of the holes are the right location but the bolt bosses are actually taller, putting that mounting point farther out from the center line.

You'll probably be better off making a new bracket, or utilizing the gen3+ mount that attaches to the oil pan.

[Will'sFiero]

Cool. Thanks!

If the hole in the front of the block is present, but not in quite the same place, I can modify the bracket to work. If the hole on the side of the block is gone, I'll have to think of another way to stabilize the bracket. The '88 brackets are thinner than the early brackets and already occasionally have problems cracking.

I saw from Joseph Upson's thread that the holes on the opposite side of the block are still there, so that's good.

It may make more sense just to fab a bracket that connects the mount holes on the pan to the Fiero engine mount.

Have any pics?

I have an LZ4 at the shop, which I'll try to remember to take a picture of, I just remembered I have that one. LOL My LZ9 is at the machine shop currently, so I can't get any pictures of it right now, but they are the same block.

the 3100/3400 used a mount bolted directly to the bottom of the cast aluminum oil pan, im sure the 3900 is similar.

The 3900 is similar in that regard to the 3100/3400, but does not have the same on block provisions that the Fiero mount pictured uses.

[Will'sFiero]

Have any pics?

[sharkey]

the 3100/3400 used a mount bolted directly to the bottom of the cast aluminum oil pan, im sure the 3900 is similar.

That area of the 3900 is very different, in fact starting with the 3100 and up it's different. However the one bolt that is used there is in the same location on the 3100 and 3400. The 3500 and newer do not have those lower holes in the block above the pan rail. Also the bolt through the front of the block is in a different location on the 3500 and newer.

[Will'sFiero]

Dam, has it been 2015 since I posted in this thread?

Does anyone have a corresponding photo of a 3900 or LZ4 3500 block?



This is the 2.hate from a 1988 Fiero. The '88 Fiero uses a different mount bracket than the '84-'87 cars. I've read that the '84-'87 bracket bolts up to the 3900. The '88's is more like a saddle. It uses the same bolts on the rear/right side of the block as the '84-'87 bracket, but also uses some bolts on the front/left side of the block. Are those bolt holes still present on a 3900?

[Will'sFiero]

2500 at 60 mph.
Another guy did a 80's Buick 3.8 into an automatic legacy and can get 600 Kmh per tank. Same 2500 at 60 mph. I'm struggling to get 400 per tank

For reference, cars with the 282 five speed turn ~2000 RPM at 55.

How big is the tank?

Getting 200miles to 55 liters at around 0F.
2500 rpm cruise

Is 55 liters your whole tank?

Do you think the "other guy" is A) Truthful and B) sufficiently concerned with details to *ACCURATELY* measure fuel consumption?

[robertisaar]

Mars is running a 3 speed and I think a pretty high ratio, and he's still knocking down decent MPG numbers, even with an ~11 second f-body(memory, FWIW).

[farmerz24]

2500 at 60 mph.
Another guy did a 80's Buick 3.8 into an automatic legacy and can get 600 Kmh per tank. Same 2500 at 60 mph. I'm struggling to get 400 per tank

[caffeine]

Agreed the gearing is probably killing MPGs

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