Chebby V8 conversion on a 90GT?
10-15-2013, 10:23 AM
#32
I was contemplating the same thing lately.
My 4.5L had to be pulled due to bad head gaskets and low compression. Turns out that the heads needed redone and had a broken oil ring in #8 cylinder.
Anyway, for about 5 minutes, I considered the swap due to cost, HP, etc. But I suddenly remembered and was reminded how much a PITA a V8 swap into a 240Z was a few years ago and the 928 swap is more complicated.
So I pulled the motor, rebuilt the heads, re-alusiled the bores, replaced the rings, all bearings, gaskets and one used piston. Presto, $2600 in parts and head work later and I have a new PORSCHE motor. I would have spent more on a swap with a bastardized engine.
BTW, if you need any Porsche head work done in Houston, try Scroggins Machine. Bobbie has expereince with these engine and his prices are extremly fair. You can even supply your own parts for additional cost savings.
IMHO, a Chevy swap in a Porsche is like viewing modern art. It qualifies for "art" and it may be worth some money to someone, but it still looks like shat to me.
My 4.5L had to be pulled due to bad head gaskets and low compression. Turns out that the heads needed redone and had a broken oil ring in #8 cylinder.
Anyway, for about 5 minutes, I considered the swap due to cost, HP, etc. But I suddenly remembered and was reminded how much a PITA a V8 swap into a 240Z was a few years ago and the 928 swap is more complicated.
So I pulled the motor, rebuilt the heads, re-alusiled the bores, replaced the rings, all bearings, gaskets and one used piston. Presto, $2600 in parts and head work later and I have a new PORSCHE motor. I would have spent more on a swap with a bastardized engine.
BTW, if you need any Porsche head work done in Houston, try Scroggins Machine. Bobbie has expereince with these engine and his prices are extremly fair. You can even supply your own parts for additional cost savings.
IMHO, a Chevy swap in a Porsche is like viewing modern art. It qualifies for "art" and it may be worth some money to someone, but it still looks like shat to me.
T
10-15-2013, 02:23 PM
#34
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10-15-2013, 02:58 PM
#35
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I'm not looking for more power, nor am I looking for a tracker. I just want a car I can enjoy for a few hours without spending the weekend tweaking and fiddling with stuff. It's been a constant hassle with the Porsche engine, and I've had Chebbys that will run for years without more than oil changes and some light simple mx.
As for the Renegade conversion, I haven't done one, and I could do all the bits myself, but that's what sounds like pulling the engine time, after time, after time. Once I get the clutch, bellhousing, and motor mounts sorted(like they have), all the rest can be done with the lump in the chassis. PS lines, AC lines, fuel delivery, water cooling can all be done with the engine in. The hard metal stuff is what I want the Renegade for. Also have to figure out the tach and the senders for the gauges but all that is doable with the engine in.
I might have to do one or two pulls, but if none of the acc are connected pulling the Chebby motor is pretty easy as long as the hood is off. Also have to worry about exhaust, but that can be done with the engine in most times. I can prolly start with the headers on and see if they fit. If not, lifting it up isn't a big issue. Still thinking about it, but leaning toward the swap.
As for the Renegade conversion, I haven't done one, and I could do all the bits myself, but that's what sounds like pulling the engine time, after time, after time. Once I get the clutch, bellhousing, and motor mounts sorted(like they have), all the rest can be done with the lump in the chassis. PS lines, AC lines, fuel delivery, water cooling can all be done with the engine in. The hard metal stuff is what I want the Renegade for. Also have to figure out the tach and the senders for the gauges but all that is doable with the engine in.
I might have to do one or two pulls, but if none of the acc are connected pulling the Chebby motor is pretty easy as long as the hood is off. Also have to worry about exhaust, but that can be done with the engine in most times. I can prolly start with the headers on and see if they fit. If not, lifting it up isn't a big issue. Still thinking about it, but leaning toward the swap.
The 928 engine is the most reliable, most bullet proof engine there is, out of all of those other Porsche engines...so I'm not sure why you have had such a poor experience with your GT engine. Some of the items you listed sound like "high mileage" or maintenance issues....while others sound very strange, to my ears. How many miles are there on this beast?
10-15-2013, 03:03 PM
#36
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Don't expect a low mileage 928 that did not have the coolant changed, every 2 years, to not have a head gasket/cylinder head deterioration problem. As long as the block is not "eaten up" don't hesitate to buy one....but put the cost of removing and repairing the heads into the cost of the car....
It's reality. None of those low mileage "garage queens" are going to be exempt from this, at this point in time.
10-15-2013, 03:24 PM
#37
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Don't expect a low mileage 928 that did not have the coolant changed, every 2 years, to not have a head gasket/cylinder head deterioration problem. As long as the block is not "eaten up" don't hesitate to buy one....but put the cost of removing and repairing the heads into the cost of the car.....
475hp/460lb.ft
10-15-2013, 03:40 PM
#39
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10-15-2013, 04:13 PM
#40
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I have yet to see a Porsche 928 engine into Corvette or Camaro conversion kit offered in the market. Maybe there is one. Now I'm finding there are at least three different Corvette/Chebby engine into 928 kits. In fact, I've never heard of a 928 engine into an anything-else kit. I know that one or two were put into boats way back but as I recall they were pretty sketchy.
But -- the 928 is the most reliable engine ever.
But -- the 928 is the most reliable engine ever.
10-15-2013, 04:17 PM
#41
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And on another of those 'reliable' data points, I've had several contacts recently asking about the status of the engine should I proceed. Along with some partially tongue-in-cheek comments in this thread.
It's not that something can't be made reliable, or isn't reliable in general, it's a function of the amount of time and money to maintain reliability. In the Chebby world that ratio is much, much by a factor of 5 or more lower than the ratio of the 928 engine.
It's not that something can't be made reliable, or isn't reliable in general, it's a function of the amount of time and money to maintain reliability. In the Chebby world that ratio is much, much by a factor of 5 or more lower than the ratio of the 928 engine.
10-15-2013, 04:30 PM
#42
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And on another of those 'reliable' data points, I've had several contacts recently asking about the status of the engine should I proceed. Along with some partially tongue-in-cheek comments in this thread.
It's not that something can't be made reliable, or isn't reliable in general, it's a function of the amount of time and money to maintain reliability. In the Chebby world that ratio is much, much by a factor of 5 or more lower than the ratio of the 928 engine.
It's not that something can't be made reliable, or isn't reliable in general, it's a function of the amount of time and money to maintain reliability. In the Chebby world that ratio is much, much by a factor of 5 or more lower than the ratio of the 928 engine.
But for some of us the Porsche engine holds a special mystique that gets a hold of your soul. It is a work of art. I actually like working on it, but I have been accused of being masochistic at times....lol
10-15-2013, 04:57 PM
#44
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Doc for the benefit of those playing along here what exactly was the reason for the demise of your GT engine?.
What about letting someone else repair this engine and then you swap it in.
You should have a good support group around.
Or maybe send the engine to GB and let him work some magic.
Sell off the American iron to pay for the fresh GT stroker engine.
just a few thoughts.
Then your car will be more of an investment with the Porsche engine installed,
as opposed to butcher bird ( not meant as a derogatory remark )
This will also have to depend on the condition of the GT chassis your working on, if the paint is old the interior worn the, chassis parts worn,
then it may be approaching parts car status anyway,
and without a huge influx of cash it could be a why bother question.
Tony is putting American iron into his car along with a 6 speed and it looks very well done,
BUT his approach is from a bare bones chassis restore,
What would your ideas be here just an engine swap with no other mods?
What about letting someone else repair this engine and then you swap it in.
You should have a good support group around.
Or maybe send the engine to GB and let him work some magic.
Sell off the American iron to pay for the fresh GT stroker engine.
just a few thoughts.
Then your car will be more of an investment with the Porsche engine installed,
as opposed to butcher bird ( not meant as a derogatory remark )
This will also have to depend on the condition of the GT chassis your working on, if the paint is old the interior worn the, chassis parts worn,
then it may be approaching parts car status anyway,
and without a huge influx of cash it could be a why bother question.
Tony is putting American iron into his car along with a 6 speed and it looks very well done,
BUT his approach is from a bare bones chassis restore,
What would your ideas be here just an engine swap with no other mods?
10-15-2013, 05:00 PM
#45
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Interesting turn to this thread. To the casual observer or 928 naive sounds like the motors make better boat anchors. Could not disagree more. It's all in the maintenance and use. And by use I mean it needs to be used.