Glad to have a V8

[the]

What I'd also love to have is a big HP Chevy V8 928!

How much HP is your colorful engine putting out? If I had that car, I'd yank that and put in a 500-600 HP SBC.

Vrrroooom!

[Jim Smolka]

Why put in a SBC into a 928 when a big block fits in there so nice???

[m21sniper]

Originally posted by the
I like the 928 too. And a 928 engine is great in a 928, uber-cool replacing an 80 hp VW engine in a 914 (gawd, I'd love to have an S4 powered 914!!), but why in a 911?

All that work, plumbing, weight, cutting, etc. etc. etc. to get what, 300 costly hp?

All the work of the Chebby, but none of the benefit (i.e. a cheap 400-500 hp). Just throw a stock 300 hp 911 Turbo engine in for less money.

Supercharged 928 motors regularly put out 450+ RWHP.

I mean if you gotta have an 8 in a 911, why not a Porsche 8?

That's how i'd do it.(not that i would)

[m21sniper]

Originally posted by the
What I'd also love to have is a big HP Chevy V8 928!

How much HP is your colorful engine putting out? If I had that car, I'd yank that and put in a 500-600 HP SBC.

Vrrroooom!

About 325rwhp at 2900lbs. Mid 13 second quarter miles- naturally aspirated.

And you're not going to get a 7000rpm American V-8 that'll actually last for any kind of reasonable money, let alone one that sounds like this. Video:



The initial acceleration in that vid is a 5mph to 70mph run in an elapsed video counter time of under six seconds. Now put that motor in a 2500lb 911. Then supercharge it.....vrroooooom.


4.7 liter 'alusil' OHC fuel injected V-8. Note factory stock main/head studs and full main girdle.

PS, i bought my 928 for less than the price of a bone stock LS-1 crate motor(and have been driving it for 4 years and 31k miles so far).


You're damned right there's no substitute!!!

[m21sniper]

For the record, do not misconstrue my remarks as anti-911. I love em. I just like my 928 even better. Now if only i had an extra $5500 for the turbo kit...

[the]

If it's true that putting together a 400-500 hp 928 V8 costs the same or less than a 400-500 hp SBC V8 and will even last longer, then I'd agree, someone should develop a kit to put these engines into everything like the SBC is put into everything (914, 911, 944, Jaguars, etc.)

[Jims5543]

Bare block no internals weight is 130 lbs. Now, I guess the crank, connecting rods, pistons, heads, intake, headers, and various little other parts including the water pump, altenator, flywheel and on and on only weigh another 270 lbs?

And somehow this engine is even lighter than my 1.3 liter Rotary engine. No matter what forum I am on there is always a guy with an LS1 that swears his engine is lighter than anything you have.

[m21sniper]

The problem is that there are so few 928 V-8 motors around. It was a very low volume car. I think world wide sales only topped 2000 units a couple times during it's entire 18 year production run. The 928 was the flagship of the Porsche line, so it was intended to be highly exclusive and low volume. I rarely see another 928 on the road (probably less than a dozen in the 4 years i've had the car). Also, buying 928 motors is not cheap. What IS cheap is buying older model 928s with perfectly good running motors in them(esp. old neglected junkers).

To just go buy a 928 motor at the dealer(i can any factory Porsche motor at wholesale for anyone interested) would cost you about $8 grand. Used they're about $3500. However, a smacked up 84 Euro with a 310hp 4.7 liter mechanical injected V-8 will only set you back about 3 grand for the whole car, and after you get done parting it out, the motor will end up having cost you virtually nothing.(while 928s have not held their value in general, the parts very much have, lol)

There are also a wide variety of motors that were used.

The US 928's started with the 219hp US 4.5 liter in the 78-82 models, and gradually increased in displacement and power to the 345hp 5.4liter motor in the last GTS models. All have their plusses and minuses, but even the early mechanical injection 4.5 models will approach 400rwhp with a supercharger running a mere 6lbs of boost.

The motors are also fully strokable too, and HUGE power gains are available going that route. The top 928 racer is running a naturally aspirated 6.4 liter stroker and is putting out close to 600rwhp naturally aspirated. Of course stroking a 928 motor is BIG money, but the results are worth it if you have the extra coin laying around.

But, say you bought an 83 US 5spd for $4000 USD in 'fair' shape(which you could do if you perused ebay for a while looking for the right car). For the additional cost of $3500 USD you can add the stage II complete supercharger kit (or for $5500 the turbo kit), approach 500rwhp, and for under 8 grand you have a V-8 PORSCHE powered, and highly exclusive supercar that will easily top 190mph, run will into the 12 second 1/4 mile ET range, and generally outperform cars costing more than 10x it's value....including in the curves (esp. if the 928 has the factory Bilstien/Eibach/limited slip options, like mine).

The 928 is IMHO the greatest bang for the buck on the roads today. Thank god the porshe-phile purists didn't 'take' to them....cause by rights the cars should be worth 4-6x what they are, based on actual merit and quality.

Go figure...

[the]

Is just throwing a supercharger or turbochargers on a bone stock 150,000 mile engine a good idea?

[m21sniper]

Originally posted by the
Is just throwing a supercharger or turbochargers on a bone stock 150,000 mile engine a good idea?

If you check out the exploded view above, the 928 motor is built with what- on any mere mortal engine- would normally be a 'race only' full main stud girdle(as well as head and main studs), and uses an "Alusil"(aluminum silicone) alloy block so hard that it doesn't even require steel cylinder liners!

There are a lot of guys with supercharged hi-mile 928 motors on the 928 sites, especially rennlist. One of them that's running a supercharger has 180k miles on his i think.

To give an idea of the strength of these motors, i missed a shift a couple months ago, and watched the tach on mine wind past 9k RPMs(and nothing broke!)......talk about a pucker moment!

The motor is everything you'd expect from a Porsche V-8 flagship engine, and then some. When i got out of the service i used my GI bill money to get a trade school auto tech education, and worked in the field for close to a decade. Having worked on all manner of hot-rods and cars, i have never seen an engine as well put together as that of the 928 in any other car in all my days.

It is an engineering marvel, and a true masterpiece of design....IMO, of course.

The one drawback to the 928 engine is it's weight. It is a very heavy engine(esp. for an alloy one), but that is due to it's overly-robust construction.

LS series GM motors are also great motors(and known for their fantastic light weight), but to maintain the true "Porsche character" of a car, a 928 V-8 is IMO the way to go over a GM motor.

[the]

Originally posted by m21sniper

To give an idea of the strength of these motors, i missed a shift a couple months ago, and watched the tach on mine wind past 9k RPMs(and nothing broke!)......talk about a pucker moment!

9K ain't no thang.

[kach22i]

Originally posted by Jim Cesiro
You mean like this?

Click here to see Video

March 2006

This was with your old engine?

Is the new one back from the shop yet?

They just salted the roads here in Michigan, I'm in pain - Porsche in the garage for four months - at least.

[Jims5543]

Originally posted by kach22i
March 2006

This was with your old engine?

Is the new one back from the shop yet?

They just salted the roads here in Michigan, I'm in pain - Porsche in the garage for four months - at least.

That was with my old engine with 1/2 the compression it was supposed to have. Kids, when your car overheats do not make excuses and drive it anyway. LOL!

Engine has been done for a while, the finishing touches are being put on the fuel system, imagine fuel lines as big around as your index finger from the fuel pump to the fuel rails. It will support 700RWHP now and I am shooting for over 500 to the wheels. All from a little (heavier than an LS1) 1.3 liter.

I miss that car a lot. I cannot wait to get behind the wheel again, the break in will be murder....

[sammyg2]

Not to diss a 928, but I've never had to replace a timing belt at 40k on a chebby engine, or the water pumps for that matter.

I got well over 1000 hp out of a "modified" chrysler hemi once...

[m21sniper]

Originally posted by the
9K ain't no thang.

It is in an 8.

[m21sniper]

Originally posted by sammyg2
Not to diss a 928, but I've never had to replace a timing belt at 40k on a chebby engine, or the water pumps for that matter.

I got well over 1000 hp out of a "modified" chrysler hemi once...

The timing belts are normal wear items. You could certainly get 60, 70, maybe 80k out of one. Not wise on the interference models....but entirely possible. The water pump is a 'while you're in there' job, so they're usually done at the same time. The entire procedure is a $400 DIY job.

I never really messed with many mopars because the prices were always so much higher, but i have definitely blown up my fair share of SBC motors.

[Joe Bob]

Bringing this back from the dead......

[Porsche_monkey]

[CurtEgerer]

Just the ticket for those V8 conversions

[Jim Richards]

Wow, a rear seat shifter. That's way cool.