Fishey

I prefer a supercharger to a turbo.


I just dont like having to wait for power when I get on/off/on the throttle. I know the Turbo will almost always make more HP when setup in a comparable enviroment but thats not extremly important to me. I do think a good solution to this problem is adding water injection + N20 for a higher RPM window (3500-6500rpm). However I am sure that the turbo owners could also add N20 and see even better gains.

hacker-pschorr

Fishey,
I agree - us having 16V 944's also puts us in the category of wanting more low end power.

One point to this I don't think has been brought up yet is overall design simplicity. I know the turbo side argument will be a properly setup turbo should not have lag with today's turbo's, computers etc... problem is our cars are NOT turbo cars from Porsche. We do not have their team of engineers, decades of on track testing etc..... so from a simplistic point of view the SC will always win over a turbo just because it is 100x's easer for the average joe to install. The redesign of exhaust manifold alone puts a turbo setup way over the top vs a supercharger. The 944 is lucky to be able to borrow a 944 turbo header - the S and S2 don't have this luxury, neither does the 928.

I love John's design - it's beautiful motor (post that pic!!) but the complexity of that setup is far greater than the SC kits Tim and Andy offer. That is why a lot of people run superchargers over a turbo. I run with a F-body club at Road America - superchargers out number turbo's with this group at least 10 - 1. I'd be willing to bet simplicity was the #1 factor.

Fishey

The cost to make a turbo not have lag is extreme and even so they still have lag.

Geo

Wow, this is the sort of analysis that leads to disasters.

Top fuel cars use superchargers because turbos are illegal.

Rich Sandor

I would disagree to some extent. The lag will always be there, but you can actually reduce it to the point where it's not even noticable anymore. And it isn't an "extreme" cost ratio either. Besides, turbo lag is part of the "character" of these cars. Some people have fun with it, some people hate it. whatever!

I've driven supercharged cars before and I like them as well as turbo'd cars. My plan is to someday get a 928S4 as well and put that new supercharger kit on it.

That way I'd have the best of both worlds!

Either way, you gotta admit, Forced Induction, turbo or Super, is a great way to make more power!

Geo

This is really funny. Lot's of kids running around today with better engineered turbo set-ups than a 951, especially when you consider the cross-over set-up and 20 year old technology. Exhaust manifolds are simple to make.

Geo

The cost is not extreme. It simply takes good matching of the turbo. Extrude honing the turbine housing improves spool-up and gains efficiency a well. Extrude honing isn't an extreme expense by any stretch. Ball bearing center sections can get a bit pricey and they do reduce lag, but in the grand scheme of building a turbo set-up the cost is not extreme.

Geo

So tell me again how there is no lag in a supercharger?

Dark Lightning

You'd be amazed what a 25-50hp shot can do to low rpm spool.

Dark Lightning

It's all about point of view and choice of words.

You get *PARTIAL BOOST* instantly since the supercharger is belt driven, but you don't get *FULL BOOST* until redline. That's the nature of the beast.

With a turbo, you get *NO BOOST* instantly because it's waiting on exhaust gases, but you get *FULL BOOST* from 3000 RPM 'til redline. Again, nature of the beast.

Proper shifting will keep any car > 3000 rpm and in prime turbo territory, but that rpm range isn't where superchargers shine.

It's all about personal preference, driving style, and race type.

You may now return to your regularly scheduled cat fight.

hacker-pschorr

Now I know your just trying to be difficult - plain and simple.

Care to list how many companies make turbo kist for Honda Civic's (I know this is the market your talking about)
Care to list how many companies make turbo kits for NA 944's?

Apple's to oranges and you know it.

Ever change the exhaust manifold on a 928? I have
Ever design a set of headers for a 928? I know people that have - simple would not be the word they use. Even John has been quoted time and time again about the "fun" he had getting a set of headers to fit with the turbo.

Anything can be easy to make. Midas can weld up some headers if I ask them to, will they be quality units like a factory turbo header? I doubt it.

There is no comparison, a SC intall is easier to install and design than a TT setup. Even more so when you throw the 928 into the ring.

Rich Sandor

"easier" does not = "better"

hacker-pschorr

no sh*t -
but I'm basing all of my comments on the 928 side of things. Tim Murphy and Quick Carl's setup is cost effective - solid as a rock - and easy to install. I'm saying that no way any turbo setup will ever equal the simplicity of Tim's SC kit (or Andy's, but I've never installed one of his so I cannot say).

"better" is relative, always will be, so not a good term to use anyway.

EDIT -
If it makes you happy, replace "easy" with "simple" in my last post. Im my opinion, making somthing more simple is always better if it does not sacrifice quality. Tim, Andy, and Carl's kits to just that.

The only known produced turbo "kit" was Calloway's for the 928 - ever see one? How about his 944 kit? How reliable were those? Tim has already sold 4 - 5 times as many SC kits as Calloway did. All running strong.

Geo

Exhaust backpressue will be the same, boost for boost. Between the exhaust valve and the turbine wheel there will be pressure, but that is what is powering the turbo. Proper sizing will minimize this.

Show me the data on the exhaust backpressure. I think that number is pulled out of thin air. Also, the cats in our cars are ancient history crap. A modern cat creates virtually no reduction in power. Sport Compact Car tested a Random Technology cat in a 240SX vs. a "test pipe" and found zero change in hp and a 1 ft/lb loss of torque with the "test pipe."

Saying there will be no additional backpressure in the exhaust with a SC set-up is pure poppycock.

Sorry, but that's a lame argument. Totally lame. What you are talking about is a packaging issue. Poor packaging with either will have the same issues to deal with.

Right.

OMG. Like the supercharger is what made a difference. There are so many things that affect on-track performance that are controlled by the rules that no rational person can argue this means anything what-so-ever. In fact, the Speedvision series is administered to create as much equality as possible and rules can change from race to race even to make this happen.

Cost. BTW, they are not supercharged either.

The point is, the pressure in the cylinder is such that scavanging becomes minor. I'm not saying it's eliminated. My point had nothing to do with overlap. Yes, I talked about what was being pumped into the engine. The point is that what goes in must come out.

So how does a supercharger not have lag? You've either got boost or you've got lag.

Geo

No I'm not trying to be difficult. Nor is it apples to oranges. I have plenty of friends who have fabricated their own turbo set-ups. I also know folks who make their own manifolds - everything from simple log style manifolds to equal length runner manifolds. In my case, I chose a factory turbo engine for my G20, but I fabricated all of the turbo plumbing myself. But I know people who have fabricated everything and these are guys that work in shops. They just do their homework and work at it.

There is no reason there cannot be a turbo kit for a NA 944. But nobody has put forth the effort. And that is just one of the differences between the 944/951 community and the rest of the import community. I'm not dissing anyone or the 944/951 community. Just pointing out a fact.