76-77 vs. 79-88
03-02-2004, 01:52 PM
#1
Racer
Thread Starter
76-77 vs. 79-88
If you were to buy a 930 for a play car on the street and some DE time, what are your thoughts on the following?
Obviously the 76/77 is much cheaper and would allow an easy cash buy in to a 930. I could for the same money, buy a better car (condition).
I know some of the obvious short comings like weld on fenders, smaller cc, less brakes, and less hp without an I/C.
How much of a deficit would this be on a modified car? Stephen...please add your thougts since you might likely be the one who would see this engine in the following off season.
I figure the engine would end up being uprated eventually, less hp would allow me to learn to drive it, I would upgrade an I/C anyways, strongly considering EFI before much hp (nothing against CIS, just more familiar with EFI aftermarket), thinking eventually big brake kit anyway, and aftermarket lightweight body panels aren't out so weld on flares isn't a huge issue for a play/track car.
I don't know of other issues, may have over simplified, haven't yet researched how hard or the limiting factors of the 3.0. Heads seem to be easily found but not sure of 3.3 crank in same case...need to pull out the books.
Opinions...come on everyone has one! HP junkie in waiting (until I can really drive
Thanks for reading all that,
Luke
Obviously the 76/77 is much cheaper and would allow an easy cash buy in to a 930. I could for the same money, buy a better car (condition).
I know some of the obvious short comings like weld on fenders, smaller cc, less brakes, and less hp without an I/C.
How much of a deficit would this be on a modified car? Stephen...please add your thougts since you might likely be the one who would see this engine in the following off season.
I figure the engine would end up being uprated eventually, less hp would allow me to learn to drive it, I would upgrade an I/C anyways, strongly considering EFI before much hp (nothing against CIS, just more familiar with EFI aftermarket), thinking eventually big brake kit anyway, and aftermarket lightweight body panels aren't out so weld on flares isn't a huge issue for a play/track car.
I don't know of other issues, may have over simplified, haven't yet researched how hard or the limiting factors of the 3.0. Heads seem to be easily found but not sure of 3.3 crank in same case...need to pull out the books.
Opinions...come on everyone has one! HP junkie in waiting (until I can really drive
Thanks for reading all that,
Luke
03-03-2004, 12:15 AM
#2
Rennlist Lifetime Member
Luke,
I would start with the later version because of the brakes, the fuel system, the ability to add a larger intercooler and the ability to go to 3.4 with less problems. The 3.0 has 6/5/1 compression and needs a different intake to accommodate the new intercooler. If EFI is in the future than none of this will matter of course. I think it comes down to how much you want to spend now verse later and how far do you want to go. If you choose to do the EFI route and make the car a monster then go with the older version. This will be a creation of your own. If you choose to stay within the limits of the CIS then go for the 78/79. In fact, if the overall goal is to do suspension, engine, body etc just grab a SC chassis and build a motor from scratch. This will save you the upfront cost of spending a premium for a "930" or "Turbo Carrera"
Lots of question to your questions. Sorry
We need to make sure we find the right combo that works for YOU 
I would start with the later version because of the brakes, the fuel system, the ability to add a larger intercooler and the ability to go to 3.4 with less problems. The 3.0 has 6/5/1 compression and needs a different intake to accommodate the new intercooler. If EFI is in the future than none of this will matter of course. I think it comes down to how much you want to spend now verse later and how far do you want to go. If you choose to do the EFI route and make the car a monster then go with the older version. This will be a creation of your own. If you choose to stay within the limits of the CIS then go for the 78/79. In fact, if the overall goal is to do suspension, engine, body etc just grab a SC chassis and build a motor from scratch. This will save you the upfront cost of spending a premium for a "930" or "Turbo Carrera"
Lots of question to your questions. Sorry
We need to make sure we find the right combo that works for YOU
03-03-2004, 01:18 PM
#3
Racer
Thread Starter
Stephen,
Of all the readers of this thread, your likely the most busy with Porsche Forum answers, yet you answered.....so thank you. This along with your reputation is why I consider you highly (and your in my area of the country vs. California) for the likes of a build up.
So, how much harder would it be to convert a 3.2 or 3.6 to a custom turbo than to do a custom build up on the 3.0 or 3.3. I know this has been discussed in near nauseam on the "other" forum. I know that it has been done with great success by some at home (famed street racer over there) and by those like Protomotive. There seems to be some debate on how well the different alloys hold up to the heat of the turbos. I'm not looking at a 750hp beast, but maybe more in the 450-500hp end goal. Like you I come from the Mustang world and blowers with water cool. Fact I've considered (though less desirable to me) the 996 for the sake of familiarities in thermal and build techniques.
Not looking for trade secrets and I guess I'll need to call you before I make a purchase to avoid the mistake of going down the wrong "road". Unlike our Mustangs, these parts aren't pocket change.
Can you or others give me just the foundation to do some personal research on this matter of turbo'ing an SC or later engine. Or did I misunderstand you in doing an engine conversion to an SC chassis?
TIA for any input. I know you guys have opinions so please give them.
Luke
Of all the readers of this thread, your likely the most busy with Porsche Forum answers, yet you answered.....so thank you. This along with your reputation is why I consider you highly (and your in my area of the country vs. California) for the likes of a build up.
So, how much harder would it be to convert a 3.2 or 3.6 to a custom turbo than to do a custom build up on the 3.0 or 3.3. I know this has been discussed in near nauseam on the "other" forum. I know that it has been done with great success by some at home (famed street racer over there) and by those like Protomotive. There seems to be some debate on how well the different alloys hold up to the heat of the turbos. I'm not looking at a 750hp beast, but maybe more in the 450-500hp end goal. Like you I come from the Mustang world and blowers with water cool. Fact I've considered (though less desirable to me) the 996 for the sake of familiarities in thermal and build techniques.
Not looking for trade secrets and I guess I'll need to call you before I make a purchase to avoid the mistake of going down the wrong "road". Unlike our Mustangs, these parts aren't pocket change.
Can you or others give me just the foundation to do some personal research on this matter of turbo'ing an SC or later engine. Or did I misunderstand you in doing an engine conversion to an SC chassis?
TIA for any input. I know you guys have opinions so please give them.
Luke
03-03-2004, 11:17 PM
#4
Rennlist Lifetime Member
Luke,
It is my pleasure. Busy or not, I do what I love...this is it.
It isn't really that difficult. There are some things to consider as you mention. The 930 heads are of a different metal content to deal with the heat. Although the truth is the guides still burn down with a level of regularity. It is the nature of the beast. The 930 heads do handle it better, but at the end of the day you have to consider how many miles you plan on putting on the car. In the work of toys 30-50-60K miles is an eternity. So while I would like to see turbo heads used it does not have to make or break the project. We can use coating and I would anyway to help coat with heat and heat transfer.
Converting either motor is not difficult. It comes down to building it to A)make the desired hp B) hold together by using the proper parts. I use as many factory parts as possible so that replacement if and when something fails is not that big of a deal. So a 3.3/3.6 is not difficult to turbo. Heck, I am even guilty of supercharging an SC I owned MANY moons ago. You can turbo the SC motor as well, however if you buy a clean chassis and start from scratch start with an 3.6 motor. The benefits are not bragging rights, but low end throttle response and a better TQ band. You can safely take a 3.6 to 3.8 and make that 550HP with less than a bar! If you would rather not go EFI and want a 3.4 based motor start with a good core, or start the process with a case and make what you want. You can even so a 964 crank and stroke a 3.4 to make a 3.5. Lots of options here.
Stephen
It is my pleasure. Busy or not, I do what I love...this is it.
It isn't really that difficult. There are some things to consider as you mention. The 930 heads are of a different metal content to deal with the heat. Although the truth is the guides still burn down with a level of regularity. It is the nature of the beast. The 930 heads do handle it better, but at the end of the day you have to consider how many miles you plan on putting on the car. In the work of toys 30-50-60K miles is an eternity. So while I would like to see turbo heads used it does not have to make or break the project. We can use coating and I would anyway to help coat with heat and heat transfer.
Converting either motor is not difficult. It comes down to building it to A)make the desired hp B) hold together by using the proper parts. I use as many factory parts as possible so that replacement if and when something fails is not that big of a deal. So a 3.3/3.6 is not difficult to turbo. Heck, I am even guilty of supercharging an SC I owned MANY moons ago. You can turbo the SC motor as well, however if you buy a clean chassis and start from scratch start with an 3.6 motor. The benefits are not bragging rights, but low end throttle response and a better TQ band. You can safely take a 3.6 to 3.8 and make that 550HP with less than a bar! If you would rather not go EFI and want a 3.4 based motor start with a good core, or start the process with a case and make what you want. You can even so a 964 crank and stroke a 3.4 to make a 3.5. Lots of options here.
Stephen
03-07-2004, 03:56 PM
#5
Track Day
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What about Tranny? I have seen people swap out the 4-spd with a 915 tranny. Seems like a risky proposition. How difficult is it to change out the older 4-spd to G50/52 type?
The reason I am asking is that I am considering getting an 77 with 915 tranny. Even though this combination may work for a while, I would think a G50 conversion would be sweet in the long run.
jonn
The reason I am asking is that I am considering getting an 77 with 915 tranny. Even though this combination may work for a while, I would think a G50 conversion would be sweet in the long run.
jonn
03-15-2004, 03:11 PM
#6
Burning Brakes
jkim are you planing on doing this yourself? Then it might be lots of work since you may need change pedals and add a slave cylinder. Give Patrick motorsports a call in Arizona, he has conversion kits. They may be expensive I think $5-6k. This will be the way to go for acceleration and durability.