Want to convert NA to turbo

kamikaze · 02-04-2003, 10:20 AM

I have an 83 with new head gasket valves T belt but no bottom end. (all stock) what parts do I need to do this conversion? and what parts do u guys have that u want to sell me?

wjk_glynn · 02-04-2003, 10:57 AM

Hi,

Let me begin with the usual answer that you'll save yourself a lot of time and money by selling the 944 and buying a 951 (with all of the factory parts and engineering development).

But where's the fun in taking the easy road!

I can't make specific recommendations but I do have a list of companies that do. You could begin by talking to them to see how they do it.

Here's the link:

http://www.weissach.net/924-944-968_Suppliers.html#SuperchargersTurboConversions

Karl.

CJFusco · CJFusco's Garage

You might want to seriously consider supercharging instead of turbocharging. It is cost effective and gives you torque throughout the entire power band. However, if money isn't an issue, go ahead and turbo yours... it is easier to extract more power from a turbocharged engine than a supercharged one

PorscheG96 · 02-04-2003, 05:31 PM

Quote:

Originally posted by CJFusco
You might want to seriously consider supercharging instead of turbocharging. It is cost effective and gives you torque throughout the entire power band.

I suppose, if you consider $6k for a kit plus the labor to install it as more cost effective than a turbo...gotta disagree with you there.

Is it torque in the entire RPM band you want? How often are you reving 1800 RPM? Even then a supercharger will deliver 1 psi of boost, maybe 2 tops. How often are you at 3k RPM? Probably every time you're on the freeway or cruising around town and *gasp* that's the boost threshold of a properly sized turbo.

So once again, is it really torque across the band you're after? Or well-placed torque that comes all at once instead of waiting till you're reving the **** out of a motor before all your boost is there.

Actually, if a person was smart the boost would drop off a tad in the high RPM's where you've got the engine performing the most work...a turbo tends to drop boost, a supercharger will not. Go lean on the top and you're through...

951carter · 02-04-2003, 07:35 PM

I suppose, if you consider $6k for a kit plus the labor to install it as more cost effective than a turbo...gotta disagree with you there.
~~~~~~~~~~~~~~~~~~

EXACTLY!! You can almost buy a 951 for that!!

Is it torque in the entire RPM band you want? How often are you reving 1800 RPM? Even then a supercharger will deliver 1 psi of boost, maybe 2 tops. How often are you at 3k RPM? Probably every time you're on the freeway or cruising around town and *gasp* that's the boost threshold of a properly sized turbo.
~~~~~~~~~~~

Nail on the head again! You should not run your Porsche engine below 3k rpm anyway......n/a or turbo! It says right in the owners manual not to lug the engine......

Britwrench · 02-04-2003, 07:39 PM

So the obvious answer is to supercharge and turbo it..........
just buy a 951, you'll be so much happier....

ae1969 · 02-04-2003, 07:52 PM

Well if you really want to try something a little different I have a callaway turbo kit......

For 2500.00

Email me if you want pics and stuff

CJFusco · CJFusco's Garage

Wow way to rip me a new one for no apparent reason.

I've seen supercharge kits for as little as $3000. I understand the labor would be similar to that of a turbo. If the Callaway kit is really available for $2500, then obviously it is the better deal. If not... people that have supercharged their NAs seem to be ecstatic about their choice in comparison with a turbo. I have seen the testimonials, and that is personally the way I would want to go. So there.

And I completely agree that for the price I would probably rather get a nice 951. Everyone that knows Porsches knows that.

todwic · todwic's Garage

Quote:

Originally posted by CJFusco
Wow way to rip me a new one for no apparent reason.

HA! Take that! Actually, Dr. Todd Holyoak seems to favour his Callaway '83 turbo. He told me of a few advantages the pre 85.5 cars have over the later years, but this topic has been DONE TO DEATH!

944freak · 02-05-2003, 04:08 AM

porscheg96 you're wrong about the supercharger only having 1-2 psi at 1800 rpm. With the Huntley kit you have full boost at 1300 rpm. That would be 8 psi with the stage 3 intercooled kit.

944freak · 02-05-2003, 04:13 AM

Also the torque curve is straight across full torque across the powerband once full boost is there(1300 rpm). Thats around 300 lbs of torque at 1300 rpms at 8 psi.

Scott R · Scott R's Garage

But why would you only want 8 psi? Again, get the 951 and you could be looking at 19 or 20 with a few mods.

Not to mention the fact the the 951 suspension is in many ways superior to the NA. Just to get your suspension up to par your going to need to throw another 2500 in for that.

Having the advantage of having already done this, it very quickly becomes a very large money pit.

kamikaze · 02-05-2003, 06:42 AM

well I am just going for whatever is the cheapest and easiest to do. what Can I say I like torque and I like Horse power.. To the guy with the Callaway kit....I hear that the rings on the early NA's are really weak. If I did get the kit I would more than likely have to run low boost. does the kit come with fuel upgrades??? ect.. Also I am always at 3k or more on that car wherever I am going..

to anyone with a turbo.....FS 83 944 almost perfect accept for minor dings.. trade me ur car.......

scottmandue · 02-05-2003, 06:55 AM

Quote:

Originally posted by 951carter
I suppose, if you consider $6k for a kit plus the labor to install it as more cost effective than a turbo...gotta disagree with you there.
~~~~~~~~~~~~~~~~~~

EXACTLY!! You can almost buy a 951 for that!!

No disrespect but... uh...

You literally can buy a 951 for around $6K...

Just go to autotrader.com

944freak · 02-05-2003, 08:40 AM

Scott R I never said I only wanted 8 psi!!!!!! I was just correcting what PorscheG96 said although 8 psi on the na is worth a lot more hp than 8 psi on a turbo. I already found a 951 that I am probally going to buy if it's still available when I get back overseas unless my need for speed is 100% fulfilled by the supercharged na. If I had it all to do over I would have bought a 951 to start out with. I'll probally end up with both!!!!!!!!!!

PorscheG96 · 10:30 AM

Quote:

Originally posted by 944freak
porscheg96 you're wrong about the supercharger only having 1-2 psi at 1800 rpm. With the Huntley kit you have full boost at 1300 rpm. That would be 8 psi with the stage 3 intercooled kit.

Sure about that? Have any proof?

Here's some proof with a 3 psi pulley:

I don't see full boost until...well, almost 5800 RPM.

But you're right, a good 2/3 of the boost is there starting at 2500 RPM...can you legitimately tell me it's there at 1300? That's quite a claim you're making. For what it's worth, I was refering to a centrifugal supercharger when describing the build-up of boost [about 1-2 psi at 2k, 3-4 psi at 4k, and 5-6 psi at 6k] not a roots-type. Get us a dyno with boost readings starting at 1300 RPM and we'll see if you're getting 'full boost.' Unfortuntately, the early boost you get with a roots-type blower has the drawback of decreased compressor efficiency compared to a centrifugal supercharger, which is inferior yet to a turbo.

CJFusco · CJFusco's Garage

Quote:

Actually, Dr. Todd Holyoak seems to favour his Callaway '83 turbo. He told me of a few advantages the pre 85.5 cars have over the later years, but this topic has been DONE TO DEATH!

Yes, I have seen Todd's Callaway in person. It was glorious. I want it, but the asking price is kinda high for an unemployed 22-year old college kid that already has a great-condition 944 anyhow.

He promised me a ride in it next time i'm up in his neck of the woods (ie next time i need some parts for cheap)... i'm trying to think of an excuse to go up there as I type this...

XJOSHX · 02-05-2003, 12:52 PM

Don't forget the n/a has higher compression so the little boost is equal to a lot more psi with a turbo.

SoCal Driver · SoCal Driver's Garage

Another parts car in the making.

944freak · 02-05-2003, 02:48 PM

Porscheg96 I havn't saw a dyno sheet on it, I'm just repeating what Derek told me. Between 2500 and 6500 rpm there was only a .62 psi gain so he gained .000155 psi per rpm or .155 psi per 1000rpms which if you figure to 1300 rpm would be around 1.884 psi at the least if you try to figure it this way but either way most of the boost is still there at low rpms. You're right about the centrifugal SC, I was just thinking about roots. I agree by all means going with a 951 is the best bet for any new buyer wanting massive hp, but I'm sure the supercharged na will be lots of fun.