Another Small Block Conversion Argument

[Herr-Kuhn]

The fact still remains that the 32V Porsche engine can be made to outperform a Chevy swap for less money and time.

Not to be rude, but to spend gobs of money pulling out a 320 HP 32V V8 and install a 420 HP small block simply makes no sense...specifically when you can just put a little pressure on the 32V Porsche and make WELL north of 500 HP. Best of all, the engine never leaves the chassis and you don't have to lose the AC, or the ECUs, or cut and re-run wiring, etc. 420 HP...nothing to sneeze at, but it's anemic compared to what the 32V 5.0 liter is capable of.

As for all motor vs. NA...who cares? The twin turbo makes tons of mid-range power with a very low boost threshold. We're not talking about an air cooled flat 6 930 here that doesn't come in until 4,500 RPM. There is no dreaded "turbo lag" with the modern ball bearing turbochargers on a well designed system. Torque is torque, the shaft doesn't know if it is all motor or turbocharged.

All this BS about the weight of the Porsche engine...I have yet to see a full side by side comparison on weight and I've had all the arguments with the Renegade guy to the point of his math stating that the Porsche engine would have to weigh nothing for his claims to be true. Look at the bottom end on a 928 engine and you'll then understand how they go 200,000+ miles and hold up. The 350s rotating assembly is tiny by comparison.

Porsche 928S4 Twin Turbo Conversion Part16 - YouTube (start at 6:00 for the pull)

Even with this car's e-boost 2 manifold pressure control unit, a turbo speed sensor, and a full hand built dual 3" 304 Stainless exhaust, it still costs far less than doing a Chevy conversion...even a 500 HP conversion. This car is the most proven and highest powered 5.0 liter 928 built to date. Car was documented to make 650+ wheel HP on less than 17 psig. E-mail me if you want the sheets.

The best part of that day was us blowing the torque and power numbers put down by a 570+ cubic inch 1969 Mopar GTX. Even better was watching the 928 idle when the GTX could hardly be civil enough to carry on a conversation in.

[Herr-Kuhn]

Professional looking installation


Hand Crafted Bliss


Twin Twins!

[rich]

That is a beautiful install on the twins. The cars still look like the executive flagship Porsche built. Even when you open the hood. There's elegent tubing and no big ugly coil packs sitting on tiny valve covers with a rats nest of butchered wires laying everyplace. Why would anyone want to drop a tiny little V8 engine into the 928 and loose all the status that goes with owning one of Porsches most expensive, well balanced and best handling executive V8 super cars. I kind of understand the yellow MN car. The cold weather and long winters do stranges things to us here. MN is a very big hot rod, street rod and american iron street machine state. If your into cars and want some recognition drop in a big ol chevy with a blower and your king. Nobody at the street machine nationals is going to know what a 928 is much less understand or show interest in the car without a big blower sticking out of the hood. That's cool. I respect that. But first not everyone can rebuild a 928 engine. Hell, there are very few machine shops that could figure out how to bore the block.

[MPDano]

Agreed. Now that's a Pro Mod of all Mods. It's almost Art

[rich]

Ya, but it's standard fair and an expected level of build quality for a super car. Whether it's a Ferrari, Lamborghini, or Mercedes. The level of build quality is expected. Drive quality is expected. The guy that drops off his super car for mods isn't going to appreciate a 500 hp build that looks like it we done by an 8th grade shop class. More importantly he is not going to want to open the hood, wiggle the wires, blow in the gas tank and wipe oil off the garage floor every Saturday before a golf outing. Then Arrive at the links on the back of a rollback after the AC quit and the engine just stalled and over heated a mile from home at a stop light.

[not_hans_stuck]

No doubt about it, that's great looking work. Of course, just because you install an LS1 doesn't mean you have to hack it up. It might be possible for somebody to do a good job. Just sayin'.

But, at the risk of starting another flame war, I gotta tell you, 600HP isn't really a very impressive number these days for a twin turbo V-8. I know a bunch of guys that have 1000+ HP V-8's that they drive on the street everyday. Everything from CTS-V's to Novitec F360's. They all show up at Houston Cars and Coffee and park in on the same row - called the 1000HP row.

If you're gonna play the forced induction card, then you gotta do it on the LS1 as well.

I guess I just see the world a little differently. Must be because I'm a System Engineer. There's a bunch of ways to rate efficiency. In my mind, I just believe that Chevy has greater package efficiency than anybody out there with that tiny little LSx motor. There may be engines that beat it on specific output - the 997 GT3 engine blows it away from that perspective - and in stock form.

I'm just hard pressed to think of a smaller engine that makes as much horsepower - of course, the Mazda rotary is capable of big numbers but it's virtually torque free.

I see why you 928 guys are so finicky about the cars. Seems like almost every one of them I look at is totally clapped out. Seems like only last year GTS' have any value. Wonder why that is? Maybe just all the good one's are owned by guys that aren't selling them - ever.

H

[not_hans_stuck]

Originally Posted by SolReaver

OH no, Finish up what you have for sure. It will be interesting.

Forgive my ranting, it is just when i was looking around for a project 928 I saw soo many wrecks that some fool thought they could transplant an American mill into. It ALWAYS ended poorly.

Keep up the good work and drive carefully when yo get her going. That kind of engine has a tendency to get out from under you a bit too quickly.

Thanks! If those cars looked like the current crop of cars for sale right now, I think they may have started out as wrecks.

And don't think this phenomenon is exclusive to 928 swaps. I have a friend that has 3 perfect pristine classic Corvette's that he and his dad restored. One of them scored high at an NCRS show. And he owns one of the largest fleet service shops in Houston. His 96 Corvette with an LS1 swap is complete except for the wiring. The wiring loom is spread out all over the car and totally disconnected. He can't figure it out and because he put a cage in it already, none of the other shops in town will touch it because they can't get on the floorboard to see anything. It's been that way for 6 years. Everyone can get in over their head.

H

[Normy]

Originally Posted by SolReaver

Normy: What is your point?

That a long time ago, in a land far, far away, there was one 928 chevy conversion that didn't suck?

Yea, I heard that one. Even saw pictures of it. Where is it today? No, REALLY? where IS this mythical creature? Why didn't Renegade or anyone else duplicate it? Yes, a good aircraft engineer / mechanic did it once. Or so the story goes....

IS it going to show up and face my challenge? Ummmmm....No. Does Renegade have a car that will meet my challenge? NO. Does ANYONE have a chevy powered 928 that will meet the challenge?

NO....NO....NO.

Are YOU going to step up to the plate? NO

All I ask for is PROOF. ONE, living, tangible car that will DARE to go toe to toe with my plain, vanilla, stock car. Hec, I will make it easy....I will use my 924S "half engine" For Gods sake I could Face off with a YUGO and still win because THERE IS NO COMPETITION.

They are all non-street legal projects and 99 and 44/100 Percent of them are POS.

Don't debate me! Talk is CHEAP. PUT UP or shut up.

-I don't know why you posted that challenge to me when I stated off the bat that I'm a 928 purist, and would only consider a chevy conversion as a temporary measure in order to keep my car on the road while I rebuilt the M28 in my garage.

DUDE; If someone mounts some supercharged LS7 or some other crazy pushrod garbage in their car, it is going to destroy your stock 928! But what does that mean? It means nothing! You can make a chevette or a Yugo faster than any 928 if you throw enough money at it. So what's the point?

chevy conversions are stupid. They work, but they destroy the value of the car. BUT....if it keeps a 928 on the road versus a junkyard? It is a positive for the hobby.

N!

[Normy]

Originally Posted by Herr-Kuhn

Professional looking installation


Hand Crafted Bliss


Twin Twins!

OMG! I've got a boner!

N!

[Danglerb]

I'm only a practical purist. After a few years of messing with cars and especially with 928's I've learned that most changes from stock have unforeseen issues.

I like hotrods, and given spare money and time the two cars that top my list for an engine change are the 928 and the Pantera.

Twitchy, basically the 928 suspension does not seem to handle a lot of torque well, and has serious traction issues over about 450 rwhp.

At least 100 or more 928 motor swaps have been done, and that isn't including swaps from other model years. I've got some links if your curious.

Putting a Chevy motor into a 928 makes it MORE expensive to own. The factory motor and accessories aren't cheap, but they aren't the most costly parts of a 928 or the most troublesome in the normal course of ownership. That award goes to the electrical system, which gets a total diddling via conversion changes and splicing.

[harborman]

I would not put a "GM Bail out Motor Works" in my car, a Ford possibly.

[tmpusfugit]

Ford Racing Coyote 5.0 4V 412HP OHC Crate Engine sounds like a place to start....

[not_hans_stuck]

Originally Posted by tmpusfugit

Ford Racing Coyote 5.0 4V 412HP OHC Crate Engine sounds like a place to start....

Any idea how much it weighs? Those arent nearly as compact as an LS but it might fit. The 928 is a pretty big motor. I dont think it would fit in an old 911. Rufs v8 for the R8GT looks to be the same size so it might work in a 996. Interesting.

[not_hans_stuck]

Originally Posted by harborman

I would not put a "GM Bail out Motor Works" in my car, a Ford possibly.

Why not? You're part owner!

[tmpusfugit]

Originally Posted by not_hans_stuck

Any idea how much it weighs? Those arent nearly as compact as an LS but it might fit. The 928 is a pretty big motor. I dont think it would fit in an old 911. Rufs v8 for the R8GT looks to be the same size so it might work in a 996. Interesting.

Ford Racing 5.0L 4V Mustang Crate Engine Stats:
Ford Racing’s new all-aluminum 5.0L Mustang crate engine is a modern 5.0L 32-valve DOHC V-8 that uses advanced features like Twin Independent Variable Camshaft Timing (Ti-VCT) to deliver 412+ horsepower @ 6500 rpm and 390 ft.-lb.+ of torque @ 4250 rpm (with premium fuel)
•11.0:1 Compression ratio
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•Piston-cooling jets, optimized oil drainback and windage control improve high-rpm performance
•Deep sump oil pan with 8qt capacity
•Tuned composite intake manifold provides efficient air delivery and weight savings
•80 mm single bore “drive by wire” throttlebody
•Four-valve-per-cylinder aluminum heads with roller-finger followers reduce friction
•Includes manual transmission engine harness and flywheel
•Vehicle harness and PCM not included
•Use our NEW wiring, PCM and installation kit M-6017-A504V designed for street rod/project car installation.
•Does not include alternator, for alternator kit see M-8600-M50ALT
•Engine mount bosses and bellhousing mount pattern common to 4.6L modular engines.
•Direct replacement for 2011 Mustangs with engine code BG-397-AA
•Photo and specs may vary. These features apply for engine code BG-397-AA. Engines are this build code or newer while supplies last.
•Engine weight: 444 lbs

[Jon B.]

Doesn't ASP_killer on RL have a STUPIDLY fast and expensive LS7 in his car? It is a race car though, so, not really worth mentioning.

Oh, there was (is) also a guy in the Austin area that has a 400+ci sbc in his '79. It is a complete monster that he drives regularly I believe. There was also another guy that DAILY drove a GM v6 conversion in his 928. Got better mileage and was cheap. He was (is) a machinist though, so he made all the bits himself.

I think the '79 is on RL. Look up EVILpatrick. Think that's his handle. This car has been around forever.

[fb111]

Originally Posted by Jon B.

Doesn't ASP_killer on RL have a STUPIDLY fast and expensive LS7 in his car? It is a race car though, so, not really worth mentioning.

Oh, there was (is) also a guy in the Austin area that has a 400+ci sbc in his '79. It is a complete monster that he drives regularly I believe. There was also another guy that DAILY drove a GM v6 conversion in his 928. Got better mileage and was cheap. He was (is) a machinist though, so he made all the bits himself.

I think the '79 is on RL. Look up EVILpatrick. Think that's his handle. This car has been around forever.

I'd say it worth mentioning. Its the most technically advanced 928 with some incredible engineering feats. Ultimately I wouldn't be surprised if it ends up becoming the fastest 928 track car.

[Jon B.]

I want his rear suspension and trans adaptation on my car. I'd love a T56.

[Danglerb]

You might be amazed at what the right amount of money can put into anything. Years ago a customer came into Greg Brown's shop with a blown up motor in his 911 turbo and said I don't care what it costs, make it faster and more reliable. Greg put a 9.0L Donovan motor in it, and it was freaking amazing, a total monster, but still a daily driver as long as your right foot was sensible. 914's have had likewise crazy fast cars made around them, but most are in the traditional "hot rod" vein, stripped out race cars with simplified electrics.

I'd love to see a Ford mod motor in a 928. Its almost a logical progression since Ford studied the 928 motor to make the mod, and something like the one mentioned sounds like it would be FUN, right as what I see as a "magic" 400 ish rwhp.

Key measurements are width between the shock towers which I am pretty sure is OK, and top to bottom measured from the center of the crank when matched to the torque tube.

I think Asp_killer's car was on the track this weekend getting some sorting out with a new sequential transmission, but its more of a race car with a 928 body at this point.

[Normy]

Originally Posted by harborman

I would not put a "GM Bail out Motor Works" in my car, a Ford possibly.

You obviously believe that workers should work for the lowest possible price. I would like to ask you to please move to China, where your type work 12 hour days for $1.25-

Buy a Porsche on those wages buddy-

N!