Why fo the purists not like v8 conversions?

[needcash]

no one cares that it would perform better for Lots less? V8s have much more potential than a flat 6 when under a budget. weight distribution isnt an issue. a GM LS1 weighs as much as many of the flat 6s.

i dont care much about "image". meaning i dont care if something is rare or anyhting like that. So putting a chevy V8 into a porsche to make it much faster doesnt see like a big deal to me.


keep it going, this is interesting

[Allenk]

Water is good for boating. My boat has a small block V8. My Porsche-a flat 6. I think your car is your car, do what you want-but of course there are those that won't agree.

[beepbeep]

They are quite heavy and it's hard (read expensive) to do it right (cooling issues etc.)
People who opt to do this are usually "on the budget" and cut corners which results in most of these conversions being half-a**ed in nature.
If done right,with propperly solved cooling issues and DOHC V8 and good chassis i bet it would be a smoker.
Unfortunately, most of them seem to be old beaten-up chassis with big lazy iron-lump and not enough money used to upgrade brakes, suspension etc. so it can cope with added power.
I found high-performance inline 4 better choice in my case except for sound.

Anyway you go, engine-transplants are not trivial and will often leave you on your own to solve certain technical details. If you are not good at it you're in trouble...

[bigchillcar]

if you 'needcash' might need to 'rethink'...
ryan

[jmohn]

Originally posted by needcash
no one cares that it would perform better for Lots less? V8s have much more potential than a flat 6 when under a budget. weight distribution isnt an issue. a GM LS1 weighs as much as many of the flat 6s.

i dont care much about "image". meaning i dont care if something is rare or anyhting like that. So putting a chevy V8 into a porsche to make it much faster doesnt see like a big deal to me.


keep it going, this is interesting

As has been suggested, do a search, or two. This has been argued over and over; and has been tried over and over. Although there's been several "stories" of successful V8 conversions (and I'm sure there must be one or two) most are actually highly UNsuccessful. To do a conversion correctly (i.e. the car will perform at least as well as it did before) is not cheap, on the contary it's quite expensive. In fact it would generally be as cheap if not cheaper to just rebuild or replace the original Porsche engine. IIRC, Grassroots (for an article they wanted to publish) contracted with a firm (maybe Renegade?) that advertised they did quality Chevy V8 into Porsche conversions. Grassroots poured a bunch of money into the project and finally (much later than promised) took delivery of a car that had multiple upon multiple drivability and dependability problems. They spent quite a bit of time trying to sort out the problems themselves, with limited success, in their final write-up they considered the whole project a total failure. If someone is trying to sell you one of these, look long and hard at it, it almost certainly is a kludge and, even if it has been done correctly, the car will have half (or less) of the value it would have with it's original engine. The bottom line is, if you want the "dependabilty and performace" of a Chevy V8, look for a Corvette, they're great cars and have a Chev V8 already installed.

Good luck,

Jerry M
'78 SC

[masraum]

Needcash, read this thread, it's extensive Glad to have a V8

[geof33]

To tag onto EVERYTHING Jerry said.

The point is being missed. Needcash... in your (no smack intended) naivete, all you are considering is the cost of the motor.

You can pick up a cheap hunk of V8 all day long $. Then you need the entire conversion equipment $$$$$, then at LEAST a rebuilt transmission and various parts to make it function properly $$$$$, all of the chassis modifications $$$$, and suspension mods $$$$ and the all the little stuff you don't think about when your in the middle of it $$$$. And this is just to do a decent job...

Notice your own moniker... notice how many dollar signs have been shown to you in this thread.

Get a decent 911, LEARN to DRIVE it. THEN worry about going faster... All in good time. Dues MUST be paid. Simple life rule.

Does anybody else feel like fenderguy, needcash, and that other Nu-bee are the same person???

[scottb]

As Marlon Brando said in Apocalypse Now, "the horror....the horror."

That having been said, here's a website on Porsche/Chevy conversions. Not for the faint of heart or weak of stomach. Yikes!

Porsche/Chevy

[sammyg2]

The weight and balance issue is a myth often propogated by those who have not built or driven a V8 conversion car.
In fact, most of the negative things posted about V8 conversions are posted by those who have absolutely no personal experience with the subject, they are either regurgitating something they heard or read or they are speculating.

As someone who has built, owned, and raced a V8 porsche, here's my opinion:
I love the sound and feel of the flat 6.
A V8 will outperform it all day long (in N/A trim), but it loses the feel and sensation of the Porsche engine and in a small way stops being a Porsche.
I enjoyed my car but would not build another one.
It was fast, reliable, inexpensive, but seemed more like a toy than a Porsche. It still handled well but lost it's identity.

I love the way my SC feels and sounds, the way the power builds as it revs, the way it gets smoother the higher it revs. I fell in love with it the first time I drove it.
It didn't have enough power to satisfy me so I kept the engine but increased the intake pressure. best of both worlds.
Nothing wrong with a V8 Porsche if someone wants to go that way, but I grew tired of mine quickly.
It's a personal thing. Some people will like it, some will hate it, but until a person experiences it for themselves they should be careful posting their theories as facts.

[A Quiet Boom]

The very best reason I can give is that it changes the whole nature of the car, and I'm a HUGe V8 fan, just not in 911s. Let's think for a minute, Toyata Supra motors are excellent but nobody is putting them into 5.0 Mustangs again this would change the whole nature of the car. Basically a musclecar should have a big torquey V8 and the rumble that goes with it. A classic sports car should have a high performance high revving motor that retains the original feel of the car. Great V8 sportscars would be the Corvette, GT40, AC Cobra etc.

Despite my extensive knowledge of things mechanical and extracting big power from V8's I'd never put one into my 911, I'd much rather build up a twin-turbo or large displacement flat six. And while it's safe to say a V8 compares very favorably with a Porsche 6 in terms of weight one needs to ask where that weight is located. It should be obvious the Porsche's original intension was to keep the center of gravity as low as possible, even with aluminum heads on a V8 I'd bet it's safe to say the center of gravity will be raised by at least 6 inches and that's alot. Add to that the fact that many V8 engines suffer from oiling problems in road race applications and need a $2000+ dry sump system to overcome it and pretty soon it's not a cheap solution anymore. I'd be willing to bet that one could extract 500+ HP from a twin turbo six for less money that a proper V8 conversion that retains all the original functionality of the car.

To put this in perspective my drag cars engine was an aluminum headed 410" stroked windsor with stage 4 porting on the heads, custom crank, pistons and rods, ported intake, custom headers, HD block, main and rocker girdles, custom cam, roller lifters etc. It produced over 600HP in race trim and would have cost in excess of $10000 to replace. With a milder cam and intake it could be around 500HP but would still cost a fortune to reliably produce that power, With the 911 your alreadt starting with a high performance design so many of the expensive parts of a buildup are already included. 5.0 Ford blocks tend to split down the middle around the 500hp mark, I've never heard of that with a 911. A true hipo V8 has almost no factory parts whereas a hipo 911 could have mostly factory parts or at least internal parts.

It's an unmistakeable fact that V8's rule the roost when it come to max power, but it is never as cheap as people make it out to be, take it from experience. I've broken way too many factory parts to say that a big HP V8 is a cheap endeavor.

[nostatic]

like I said before, "why do you want a 911?"

I'm dead serious. If you are on a budget and want a lot of performance, you're looking at the wrong car. If you want serious off-the-line performance, you're looking at the wrong car. If you're looking to do burnouts, and have that gutteral low end grunt, you're looking at the wrong car.

So why do you want a 911?

[jmohn]

Originally posted by sammyg2
---------------SNIP--------
As someone who has built, owned, and raced a V8 porsche, here's my opinion:
I love the sound and feel of the flat 6.
A V8 will outperform it all day long (in N/A trim), but it loses the feel and sensation of the Porsche engine and in a small way stops being a Porsche.
I enjoyed my car but would not build another one.
It was fast, reliable, inexpensive, but seemed more like a toy than a Porsche. It still handled well but lost it's identity.
----------------------SNIP--------

Sam,

Having gained respect for your opinions from your many informative posts, I'm willing to believe all but the inexpensive part. "Inexpensive" to someone knowledgable about these cars and with the skills and tools to do the fabrication necessary to perform this conversion is much different than "inexpensive" to someone who must pay to have all or most of the work done. Especially someone shopping for a Porsche with less than $10K to spend. I wasn't trying to mislead "needcash", but I don't think he has any idea of the complexity of the swap he comtemplates. In fact, neither do I and I've been in on a few engine swaps in the past (an early Chrysler hemi into an earlier Pontiac was the most "interesting" as I recall).

Jerry M
'78 SC

[Zeke]

I once rode in a Jag XJ6C converted to a Chevy going out to dinner. Spoiled my dinner........

Like Sammy says, I have no direct experience to diss the Porchev because I have never ridden in one. The Jag experience being enough, I hope to keep it that way. (I have owned a Jag XJ6 with the inline 6)

I have owned a Chevy pickup of one sort or another continuously since 1965. No problem w/ Chevy, but the sound of a V8 needs to come from under the appropriate hood, IMHO.

BTW, needcash, you won't get much respect doing this, but you said that doesn't make any difference to you. It does make a difference to me. I succumb to the peer pressure not to do this because I admire and respect my peers. However, even with that in mind, I doubt I would convert any Porsche, Jag, Austin Healy, MG, or even a VW. It ain't natural. I haven't done anything like that in over 40 years of wrenching as a hobby, so it might be safe to say it won't happen.

BTW, I've owned all of the cars mentioned at one time of another, so I can speak of them. I'd like to conclude by saying that I also don't order a hamburger at a French restaurant. Some things are uncouth; some get it, many don't.

[nostatic]

Originally posted by Zeke
I'd like to conclude by saying that I also don't order a hamburger at a French restaurant. Some things are uncouth; some get it, many don't.

what about Freedom Fries?

[sundaypunch]

A V8 in a 911 makes about as much sense as taking an older Harley and dropping a Honda engine in it. If you have to ask why not do it then there is no point in explaining. It's hard to beat a big V8 in the proper car but it is wrong in a 911 on so many levels.

Pardon my ignorance, but can you even fit one of these things in the engine compartment? The few pic's I've seen have them in the back seat.

[Joe Bob]

AHEM....now for the hearing impared, WATER SUCKS

[no substitute]

You answered your own question. By definition purists want the entire vehicle to be a Porsche. If you want a V-8 in yours, by all means do so.

[techweenie]

People who say a V8 doesn't screw up a 911's weight distribution do not know bupkis about 911s.

They're thinking in only one axis. A standard 350 'crate' motor throws another 40-50 lbs behind the rear axle -- a long ways behind. And even through a fluid-filled front radiator and lines add some weight to offset it, they *add weight*. You can get lighter V8s, like LS-1 engines with aluminum heads and block, but the ready-to drive price is probably going to be comparable to a very good 3.0 or even a 3.2

Now, let's go to the other axis -- the part that V8 advocates don't want to talk about: a flat boxer engine of any kind has a low center of gravity. A V8 has a higher center of gravity. Put a dry sump system in the V8 and snuggle it down in the chassis as low as you can, and you still have the center of mass several inches above where it was (not to mention, you've added more weight again).

No, you can't approximate the driving experience of a 911 with a V8. You can add some horsepower and a bunch more torque (which most Porsche transmissions don't like much), but it won't necessarily be a lot less expensive. And you will KILL the resale value of the car.

[masraum]

Soooo

Are you guys saying it's a bad idea????

[Schrup]

Hey, can I put a 3 liter aircooled engine in a early eighties Corvette? I wonder what kind of response that would get on a Chevy BBS. I don't see the point of kicking a dead horse.