Weissach

'87-'95 model year cars have held their value very well for the past 5 years. They haven't lost their value at all, this is incredible. The GTS models have even gone up in value! With these elevated prices(espcially the GTS models), they are "worth" maintaining.

docmirror

A lot of interesting reading. I have not installed a SBC in a Porsche so I have only a laymans opinion of the whole thing. I wouldn't be against it, provided the work were done well and the rest of the car was maintained to proper standards. One of the hallmarks of this chassis is it's remarkable handling and ride(GT's a bit harsh). The SBC engine has undergone some amazing changes in the last 30 years. What was a doggy limp lump in the mid-70s, is now much more state-of-practice in terms of port flow, reduction of mass and friction, and improved materials.

The poor chap that blows a GT or GTS engine is in a bit of a pickle. Particularly if he/she isn't a DIY kind of person. Having the engine exchanged like-in-kind on a GT/GTS is a big money loosing proposition. There are limits to everything, and at some point everyone has to justify the expense for a $80,000 supercar that is now worht less than half of that, and often less than 1/4 of that(GT). Knock wood I never find myself in that position, or I would seriously consider the SBC.

However, unlike many of the crate/over counter types. I would start with a good late 80s bare block, get my own Alum heads(Trick Flow), source the lower end from a race builder and go to Electromotive for the fuel spark control. This gives a lot of flexability and I can get just the torque curve, and power ratings I want to suit the trans/diff and chassis. The Electromotive TEC-3 is alrady setup for the basic SBC,a nd allows maximum flexability for tuning. It isn't a cheap way to go, but it's clean and reliable.

We have a poor dude on the Vintage Lambo list that has a SBC in a Lamborghini Espada. We harass him from time to time, but still provide support and encouragement. I would postulate that exchanging the Lambo V12 for a Chebby is much, much more sacreligious than the 928 to SBC swap. The value of his car is about 2/3 that of the rest of the fleet, even if he could find a buyer.

Doc, op-ed only today!

m21sniper

"The SBC engine has undergone some amazing changes in the last 30 years. What was a doggy limp lump in the mid-70s, is now much more state-of-practice in terms of port flow, reduction of mass and friction, and improved materials."

The earlier(73 and older) SBCs were a whole different animal wrt the smog motors too.

The 12:1CR 8000rpm rev potential Z28 302cid/5.0Liter is still an engineering masterpiece, even 36 years after it was introduced.
Similarly, the 70-73 LT-1 350cid/5.7liter motors are rightfully regarded as legendy performers.

Coming stock with 4 bolt main 'hi nickel' NASCAR block, steel crank, forged pistons, "pink" rods, 11:1CR, solid lifters, and 2.02int/1.60 angled plug double hump heads the original LT-1s were almost indestructible even when regularly run up to their 7000rpm redline.

docmirror

Yeah, good times. My brother had a 70-ish El Camino with one of the Z28 clone engines. Unfortunately, the smog era hit in 1973 and changed the whole landscape. Nothing wrong with the exchange from the 928, but it'll still be a 'modified'. I wonder about the valuation on a 928 GTS with a SBC in it. The earlier cars, it's probably near a wash on value, but the GTS might be quite a hit in the wallet.

Doc

FBIII

In high school a good friends mother had a 69 Z28 with an M21, 4.10's and manual steering. She used to race sedans in SCCA in the late 60's. Two lasting memories: her son missing the 1st to 2nd shift @ 7000 RPM's repeatedly one evening and watching the 7,000 RPM tach bury decisively. I don't even want to guess how high the engine revved at this point. And second having told his mother that the car was running lousy, her reply was that it was running fine up to 120. Those engines were absolutely bulletproof.

m21sniper

"I wonder about the valuation on a 928 GTS with a SBC in it. The earlier cars, it's probably near a wash on value, but the GTS might be quite a hit in the wallet."

Any engine swap would no doubt kill the value of a GTS.

I can tell you this much, if i ever blow the motor in my 928S i'm going to VERY seriously look into swapping in a Buick 3.8SFI V-6 turbo.

Save me about 300lbs(The Buick V-6 is almost 200lbs lighter than a cast iron SBC) while at the same time giving me a motor with tremendous aftermarket support, and one that can make 500hp almost literally by accident. I also have a good bit of wrenching experience on them(though i do have more on SBCs). With a Buick V-6 a full race prepped 928 could see an empty weight as low as 2200lbs!!!(Just imagine a 2200lb 928 with 600hp, OMFG).

Anyone that would would talk smack about a drivers seat tunable 400-600hp Buick V-6SFI turbo powered 928S would be welcome to meet me on the track of their choice in their P-car powered V-8 for a lesson in humility(except Anderson and Kibbort, lol).

sublimate

Jegs has them now:
http://www.jegs.com/webapp/wcs/store...0763&langId=-1

Blows my mind that you can buy a 500+ horsepower, 7000rpm, aluminum, dry-sumped motor w/ titanium rods and valves that's 150+ lbs lighter than ours for under $13k.

tammons

You dont have to do much to get 350 hp out of 350 CI.

As far as longevity, I doubt it would last as long as a meticulously maintained 928 engine, but you hear different stories.

I would say to start a 4 bolt main, forged crank, pink or forged rods, forged pistons, definatley a double roller timing chain, roller cam and roller rockers, HD oil pump, FI, and a perfect balance job, all should be a good start.

It would probably be better just to buy a new crate motor.

FBIII

That engine in the Corvette finished 5th at Le Mans this year only 20 laps behind the Audi's. It was also the first production bodied car to finish. Boy how times have changed. With Porsche not emphasizing this form of racing any longer, their top finishing car was a 911 RSR that placed about 10th.

Malibu310

My experience with the SBC in our 928s have been good overall... I've got now 4,000 miles on my race engine and so far it's been very dependable, however lousy on fuel consumption mostly due to the "race" part of the engine and the fact I decided eary on to use a race carb instead of fuel injection.

Overall the car does not feel as fast and quick as my AMG SLK, even though I have about 25% more power with the SBC vs. the supercharged Mercedes at about the same weight... mostly due to the gearing (I think).

I've ordered a new fuel injection system that will preserve the look of the carb system and (they claim) will produce at least 50% better fuel economy and better power overall. Mostly I'm hoping the injected conversion with the refinement will get the engine just a bit more responsive and take away roughness when the engine is cold.

Our blower setup so far (after the fourth engine rebuild replacing EVERY part with the best ones available) has been very dependable so far with about 3,000 miles on that engine. Since we are only going to drive the car about 3,000 miles a year it should last a decade between overhauls.

Tony

Anyone snag a picture of the hot rod at Sharktoberfest?
Chevy block with 928 heads!

Evil Patrick

Giggidy, gig, giggidy!


http://www.jegs.com/webapp/wcs/store...0763&langId=-1


-Evil Patrick
79 (THE original "bastard")
82
84 (for sale, cheap! make offer!)

Nasty 928

How about you Buy a Vette instead.

DFWX

I think you would be unhappy with a Chevy motor in a Porsche.
Rather, why not buy something like a 1986 Camero or 1983 Silverado pickup truck that comes with an SBC? Put glass packs on it and it will sound really fast.
Mark
DFWX

SharkSkin

Nabbed a few.... It was hard to get a good angle.... The guy made some wiseass comment about how he had used the only good parts from a 928, I told him that he was lucky because that's one part Ford and Chevy never made worth a damn...