Video: How to Build a 3.8L Porsche Track Monster
08-28-2014, 11:15 AM
#31
Drifting
So my C4S weighs about 3200 iirc, which translates to 11.35 lb/hp.
To get equivalent of 350hp motor (9.14lb/hp) one could lose 620 pounds, which would improve handling as well.
Even losing 300 would be equivalent to having 3.8 RS engine with 310hp. Of course then there is not much to brag about.
From what I heard, the 964 has very heavy Awd system, so just removing that would probably result in decent performance gains, and with winter tires and weight in the rear I'm not sure how much more beneficial the AWD in winter anyways.
To get equivalent of 350hp motor (9.14lb/hp) one could lose 620 pounds, which would improve handling as well.
Even losing 300 would be equivalent to having 3.8 RS engine with 310hp. Of course then there is not much to brag about.
From what I heard, the 964 has very heavy Awd system, so just removing that would probably result in decent performance gains, and with winter tires and weight in the rear I'm not sure how much more beneficial the AWD in winter anyways.
08-28-2014, 12:11 PM
#32
Race Car
I have LN cylinders in my 4.0l build and seal it with Curil T (which stays soft) and the seal is perfect!
I've heard a rumor that 3.8 slip ins tend to deform over a surprisingly short timeframe. This is not a huge problem in race engines that get torn down regularly. When long-term durability is a concern, some prefer thick-walled, bore-in, Mahle pistons and cylinders. <sips kool-aid>
Forged vs cast cylinders tends to be the difference here... Much less chance of warping in a forged cylinder. These is also the type of alloy used but that is another conversation.
Disclaimer, Yes I have the LN cylinders in my car and the car is part of a project series in Excellence, however I paid full price for the LN Cylinders and Pistons in the car so I have no kickbacks for saying anything. In my decision process I wanted the best I could afford while getting the 4.0 I desired.
The question I have is if one is doing top end ($8-10k??), it is worth it to spring for extra (12-15k) and get 3.8-4.0l version with various upgrades to get to 350-400hp? How reliable are these "new" engines? If you ever decide to sell, would you get extra money back with higher resale? or are you better off just dealing with lower HP but keeping it original and more reliable?
The other issue in making the big numbers are the heads, iat these levels it is not sufficient to just put RS valves oin the stock heads. You need to look at the CNC head oiptions (9M, Elite etc).
If you are doing this for resale, do a stock rebuild and be done with it.
You may get some money back, but not all, and it may decrease the pool of buyers as many are scared of mods and prefer factory stock. For most resale, you'd want to source as much oem RS stuff as you could I would think.
As long as you don't spin the engine much past 7000rpm, it should be reliable, but it ain't making 400bhp at that point either.
I think just slapping 3.8 P&C in there is terrible from a cost/benefit perspective (unless your originals are hosed).
To me its either a stockish rebuild or a ***** out effort making that 350 to 400bhp.
My guess is an honest 350bhp motor would cost almost $30k from a good builder, with a 400bhp motor running nearly $50k.
As long as you don't spin the engine much past 7000rpm, it should be reliable, but it ain't making 400bhp at that point either.
I think just slapping 3.8 P&C in there is terrible from a cost/benefit perspective (unless your originals are hosed).
To me its either a stockish rebuild or a ***** out effort making that 350 to 400bhp.
My guess is an honest 350bhp motor would cost almost $30k from a good builder, with a 400bhp motor running nearly $50k.
08-28-2014, 12:15 PM
#33
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It used to be that one natural progression to obtain more power was to go to a Turbo from a NA car - because for the price difference you get a car engineered for extra power, including different transmission (with closer to euro gearing), driveshafts, clutch, brakes, etc. The entire driveline was looked at by Porsche, not just the engine. But now, it seems the prices of the Turbos has risen so much that the gap is much larger, so it's not a practical option unless you really WANT a Turbo and have deep pockets.
I looked at a bunch of options when I rebuilt my engine, such as 3.8 kits, 9M heads, RS cams/valves/chips, other cams, etc., and even other options such as regearing the transmission or SC kits. All the options (to me at least) were really really expensive for the return, and I was not willing to spend the money. The return on investment if selling the car is poor, I would say less than 25 cents to the dollar.
I was also worried about cross impacts of increased power, such as the bottom end of the engine, or driveline stresses.
Weight loss is another option, but I liked having air conditioning when its hot, or carpets in the car rather than bare metal, and that is definitely an option that actually costs quite a bit too - which is only realized when you sell the car. The price for a stripped 993 is definitely lower, and the pool of buyers smaller. If you elect to put it all back, then there is the labor, paid or unpaid, to do that.
So one thing for sure though, hot rodding in the Porsche world is not cheap!
Cheers,
Mike
I looked at a bunch of options when I rebuilt my engine, such as 3.8 kits, 9M heads, RS cams/valves/chips, other cams, etc., and even other options such as regearing the transmission or SC kits. All the options (to me at least) were really really expensive for the return, and I was not willing to spend the money. The return on investment if selling the car is poor, I would say less than 25 cents to the dollar.
I was also worried about cross impacts of increased power, such as the bottom end of the engine, or driveline stresses.
Weight loss is another option, but I liked having air conditioning when its hot, or carpets in the car rather than bare metal, and that is definitely an option that actually costs quite a bit too - which is only realized when you sell the car. The price for a stripped 993 is definitely lower, and the pool of buyers smaller. If you elect to put it all back, then there is the labor, paid or unpaid, to do that.
So one thing for sure though, hot rodding in the Porsche world is not cheap!
Cheers,
Mike
08-28-2014, 12:24 PM
#34
Race Car
Mik I am with you. For people like you and me who can do the work ourselves, the cost is still substantial for numbers that are still below 993tt numbers.
I for one, while I love turbo cars and raced them for years, I really love a high reving NA engine for the track.
Of course making the car light and adding more power is the perfect recipe as far as I am concerned... My car (with carpet, but no A/C) weighs just over 2700lb and I am north of 350hp... Stock GT3's on the track are no competition.
I for one, while I love turbo cars and raced them for years, I really love a high reving NA engine for the track.
Of course making the car light and adding more power is the perfect recipe as far as I am concerned... My car (with carpet, but no A/C) weighs just over 2700lb and I am north of 350hp... Stock GT3's on the track are no competition.
08-28-2014, 04:07 PM
#35
Rennlist Member
Anyway, when we see the direction this thread has taken, maybe you guys understand why I'd just bypass the air cooled and stuff the 996 Turbo engine in if I wanted to go Stupid Power. For me, I can't really tell much difference between stock and stock+50. Sure, you look at data. But in car, unless it's competition, how often are you running Grade A tires or are fully clean on a lap? So 2MPH higher entry speed isn't all that.
08-28-2014, 06:02 PM
#36
It's amazing to me the controversy this sort of thing seems to generate, The guy had a nice motor built w/i his budget by a great shop also working w/i the customers budget, Spenser was kind enough to allow some video to be shot of the process, he didn't have to do that and many shops wouldn't allow it.
A lot of guys won't post their projects because of all the sniping and criticizing that goes on after the fact
Could things be doe differently, sure
could he have spent a lot more money for a more performance, sure
could other things be done to the car, sure
but so what
I say well done and enjoy!!
A lot of guys won't post their projects because of all the sniping and criticizing that goes on after the fact
Could things be doe differently, sure
could he have spent a lot more money for a more performance, sure
could other things be done to the car, sure
but so what
I say well done and enjoy!!
08-28-2014, 07:40 PM
#38
Rennlist Member
The most cost effective 3.8 build is one the former owner paid for. Unless they screwed it up of course . . .
There is something very appealing about the lumpy idle of the RS cam, and the slower turn over when starting due to the higher compression. :-)
You instantly know it is not a stock 993 motor. At least, that is the case with mine.
Regards,
.
There is something very appealing about the lumpy idle of the RS cam, and the slower turn over when starting due to the higher compression. :-)
You instantly know it is not a stock 993 motor. At least, that is the case with mine.
Regards,
.
Last edited by Cemoto; 08-28-2014 at 08:01 PM.
08-28-2014, 08:15 PM
#39
Race Director
It's amazing to me the controversy this sort of thing seems to generate, The guy had a nice motor built w/i his budget by a great shop also working w/i the customers budget, Spenser was kind enough to allow some video to be shot of the process, he didn't have to do that and many shops wouldn't allow it.
A lot of guys won't post their projects because of all the sniping and criticizing that goes on after the fact
Could things be doe differently, sure
could he have spent a lot more money for a more performance, sure
could other things be done to the car, sure
but so what
I say well done and enjoy!!
A lot of guys won't post their projects because of all the sniping and criticizing that goes on after the fact
Could things be doe differently, sure
could he have spent a lot more money for a more performance, sure
could other things be done to the car, sure
but so what
I say well done and enjoy!!
Its the internet, if you can't take a little bit of negative feedback, you need to take up knitting.
At least its a bloody tech thread not some bull**** about values, insurance, or which valve stem caps future owners may like best.
08-28-2014, 09:33 PM
#40
Rennlist Member
where is the controversy. A bunch of people are discussing the various benefits, costs, and drawbacks of certain motor packages.
Its the internet, if you can't take a little bit of negative feedback, you need to take up knitting.
At least its a bloody tech thread not some bull**** about values, insurance, or which valve stem caps future owners may like best.
Its the internet, if you can't take a little bit of negative feedback, you need to take up knitting.
At least its a bloody tech thread not some bull**** about values, insurance, or which valve stem caps future owners may like best.
But I'll add that putting "Track Monster" in relation to what this car was/is just sets the table for said "controversy."
(Shuddering at the thought of the internet existing in the '80s, and all the "500HP" CIS 930s that were built.)
08-29-2014, 09:12 AM
#42
Rennlist Member
