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-   Porsche 944 (https://www.germanautoforums.com/forum/porsche-944-9/)
-   -   this might sound crazy but.... (https://www.germanautoforums.com/forum/porsche-944-9/might-sound-crazy-but-3353/)

dwhita6605 05-05-2007 07:45 PM

this might sound crazy but....
 
Has anyone heard of a sr20 nismo swap? or a 1j or 2j toyota swap? dont get me wrong i love the 5.7 swap, but with todays economy its not looking to promising. This would really make the 944 more (tunable)

if anyone has anything.


let me know

Anthon33 05-05-2007 09:09 PM

RE: this might sound crazy but....
 
I'm not sure I've heard of this done but it sounds intresting. Not sure the straight six would fit as its about 4 or 5 inches longer than the standard lump. Probably possible but would be very costly and take alot of modifications such as modified bellhousing, enginr mounts, wiring harniss, prop shaft, tranny, bulkhead etc.

Lee Willis 05-05-2007 09:46 PM

RE: this might sound crazy but....
 
Those engine swaps would be fun -- do it if that's what you want --but I think your car would be faster, and have better fuel economy with the GM 5.7 liter V8, and with kits available, it would be far easier. Most of the swaps for the GM LSx series V8s include taking the bellhousing, clutch, and manual six speed transmission with it. The two top gears in that trans are overdrive gears, 6th being a ratio between .68 and .51. The LS V8 is incredibly torquey and can pull in traffic straight off of idle: you can get outstanding mpg around town by shifting at low RPM (I mean really low, like 1500-1800 RPM) and "letting the torque do the work."

Stock, my 'vette did about 34 mpg on the highway at a steady 60 mph (slightly less than 1700 RPM), about 30 at 70. Even modified, I still get 29at steady 60 mph(which is truly incredible, given the engine's power), and 19-22 on the way to work (stop signs and stop lights, city bouelvards, etc.), shifting at about 1650 RPM. My car weighs about what I imagine yours does (right at 3300 with me in it and a half tank), so I can't see you getting much better mileage with anything else.

You might check out my comments on this thread for more of fuel economy.

http://www.corvetteforums.com/m_32589/tm.htm

nobuhiko takada 05-06-2007 06:50 PM

RE: this might sound crazy but....
 
actually the sr20 motor he is speaking of. is a 4 cylinder turbo with stock HP around 200-220, with minor upgrades like front mount and mbc's among some other things it can get 300 easy, with better gas mileage than any v8 around, the motor is found in the japanese version of the 240sx, which is named the nissan silvia, if you think about it, its really the best choice for the 944, sr long blocks can be had for around 2K deliverd to your front door, i been thinking about it for awhile now, i tell you what, whoever designs a kit will be a very wealthy man, i will buy one right now and i know atleast 3 people with me on this one, **** some people swap them into 3 series bmw's, they have a kit that allows you to plug into the stock harness and everything, i cant wait for somone to drop the kit with mounts and everything,



SOLD BABY !!!!!!!!

Anthon33 05-06-2007 07:26 PM

RE: this might sound crazy but....
 
Right yor are but the JZ's are inline six which I was thinking about. If I were to go to such lengths I would use the Toyota lump, although there is the size aspect of the engine to think about, it would be a sweeter motor than a four banger lump which the 944 already has which in my opinion would pointless putting another. The JZ's are a far better, more efficent, more powerful, more tunable and sound better than that engine from a nissan primera

dwhita6605 05-06-2007 07:46 PM

RE: this might sound crazy but....
 
looks like i might start welding up some motor mounts depending on what swap i go with. if i do, i will let you guys know about it.
Dave

Anthon33 05-06-2007 08:25 PM

RE: this might sound crazy but....
 
Another engine you could consider is the Nissan RB25 or RB26DETT inline six from a skyline.

dwhita6605 05-06-2007 09:00 PM

RE: this might sound crazy but....
 
yea but waaay to expensive.

Lee Willis 05-06-2007 11:27 PM

RE: this might sound crazy but....
 
"with better gas mileage than any V8 around"

I'm going to disagree on the basis of comparing apples to apples.. A small displacement high RPM forced induction motor can provide better fuel economy than an LS2 in a 944, but only if it is cammed and tuned to provide far less performance. Even so, the fuel economy advantage will be small, and 200-220 HP -- whether that is flywheel or rear wheel that is pure wimp category in a street car weighing in around 3300 pounds with driver and fuel.No performance at all. Camry's driven by soccer Moms will outrun you. Getting into real performance territory, which means 1 RWHP for ever 10 pounds of car or less, would means cams and revs and tuning that would throw fuel economy out the window with that little four. Plus, believe it or not, that SR20 with all the goodies to make that much power starts to weigh only a bit less than what a sleeked out LS2 does -- and it has far, far less torque.
An LS2 puts around 355 HP at the rear wheels stock, which means basically a fuel economy cam and tight emissions.Install it with the right gears and a six-speed, and it will give good fuel economy and incredible power when asked. Remember the fundamental rule of automobile engines, true always: there is no replacement for displacement.

Anthon33 05-07-2007 02:00 AM

RE: this might sound crazy but....
 
It is not physicaly possible for 5.7L to be more ecofriendly than the 2.5L engine. 355hp is so small for 5.7ltres, I can't understand how someone could build such a big engine and yet have so little power, when 2.6 RB26 is over 300 stock and tunable up and over 1000 horses. Japanese inline six is the way to go. V8 too heavy...


Anthon33 05-07-2007 02:13 AM

RE: this might sound crazy but....
 
Anyway why would you want a sportscar to be economical, it wouldnt be a sportscar if it was now would it?
If you lived where I do you would be paying $2 per litre of fuel, so count yourselves lucky. :)

Lee Willis 05-07-2007 09:42 AM

RE: this might sound crazy but....
 
" . . . I can't understand how someone could build such a big engine and yet have so little power . . . "

No offense, but this is the only thing you got right -- you don't understand.I don't know you, but I will hazard a guess that you are relatively young (of course, nearlyeveryone is relatively young to me) , don't have much engineering education, but are very enthusiastic about cars, particularly those types you and your friends have. Fine, but please, no fanatical enthusiasm here for one kind over another. All cars have advantages and disadvantages and it pays to learn to gain some objectivity: this way you avoid embarrassing yourself with sweeping statements that friends can prove untrue, and you are less likely to get spanked at the track because you really didn't give the competition its due regard.

The following points you stated not always true . . . :
. . . It is not physicaly possible for 5.7L to be more ecofriendly than the 2.5L engine . . .
certainly it is, eco-freindly is more a matter of design and catalysts than anything else - ultra low emissions engines do well mostly because of the placement of their catalytic converters closer to the exhaust ports than anything else, etc. And "big" slow-turning cylinders have tremendous advantages from an emissions/clean burn standpoint, if you use them for that.
. . . V8 is too heavy: no again, that is a matter of design . . .A 100 HP/liter engineweighs roughly the same per liter regardless of its displacement, but a 400 HP/6 liter engine does not necessarily have to weigh more than a 400Hp 4 liter engine, or a 400 HP two liter engine. The GM LS-series V8s are only "big" if you look at displacement. In every other way, they are small.
For a moment, forget about displacement, and think as an engineer does when looking at a new engine project: you have to design an engine to make a certain amount of power, etc.. If you are targeting a country where cars are taxed on the basis of their displacement (Europe, Japan) you want to go with minimal displacement and high revs. But if you design for the US or Australia, etc., where cars are taxed on the basis of weight and market value, you don't care about displacement that much: you look to getting the most power out of a certain amount of total engine weight. Here, GM is just about unmatched in the world (largely 'cause it has more experience at this type of design) - something not really appreciated by a lot of folks (except by just about anyone who pays attention at the drag strip)

GM chose to build a very big-displacement, very low-reving, "lazy"engine, it has a lot of displacement but because it is targeted at relatively low revs and power levels per liter, its block is very light: an LS3 (6.2 liter, 403-430 HP depending on the exhaust) is actually lighter than the original four cylinder engine in a 944. It uses pushrods - they have their downsides, but double overhead cams make for very heavy heads, and in a V engine require four times the number of cams, cam bearings, cam followers, etc. (not just more parts, more friction), and timing chains, etc. and they all add weighrt where you want it least -- at the top of the engine. And because they are at the top of the engine they make "packaging" difficult - the engine is taller by about 3-4 inches, and its its a V6 or V8, wider by about 4 inches, too.
The net result is that the cam-in-block, pushrod GM LS V8 has low internal friction at cruising speeds compared to any engine in its power range, and it is a very compact package -- short front to back and side to side and bottom to top, and very lightweight -- stock it weighs less than a stock single overhead cam 4.6 liter Ford V8 putting out right at 110 HP less, and only a few pounds more than the engine in a 350Z. It can take mods , either normally aspirated or blown, to only around 550 flywheel before the block gets too weak for long term durability. Then, you have to go to either LS7 castings (expensive) or the "custom" C5R (very very expensive) or an iron casting instead of aluminum (cheaper than stock) which is heavy (another 91 lbs), but it will now take up to 2 BAR of boost and got to 1300 HP -1600 HP at the wheels.
There are many great engines in the world. The Porsche 3.8 liter flat six is one of them. The LS V8 is another. Some of the Japanese fours are prettygood, too, and I have always loved the V6 in the last model Supra.But its best not too let enthusiasm for one blind you for another. the LS transplant strikes me as far preferred for the 944 because the engine is compact yet powerful, will fit well down in the car and well back, too, for good wieght distribution, has roughly the same weigh as stock so it leaves chassis dynaics alone, and there is a kit already, which makes like easy. And with the 6-speed's high overdrive, it will give outstanding fuel economy, too.

dwhita6605 05-07-2007 01:19 PM

RE: this might sound crazy but....
 
Wow, this has turned to be quite the debate, but considering i have a tbi 350 just waiting to be pulled out of my 95 chevy tahoe sport. i might just go with my all too reliable chevy smallblock considering ive owned this car since there were only 20,000 miles on it. and having known all the maintance that has been done. i feel quite comfortable with making a high tourqe 944-v8 hybrid..



thanks for all the input guys.

Dave

Lee Willis 05-07-2007 02:16 PM

RE: this might sound crazy but....
 
That makes a lot of sense. You have the motor. You know the motor. (Its an LT1, not an LS series, but most of whatI said still applies). You're almost half way there.



Good luck with it.

dwhita6605 05-07-2007 02:28 PM

RE: this might sound crazy but....
 
thanks lee, soo my tbi is a lt1??? any idea on power ratios? at the flywheel? and do you think i could mate my turbo tranny to it?

Lee Willis 05-07-2007 02:37 PM

RE: this might sound crazy but....
 
Its probably about 275 flywheel Hp with around 385 ft lbs torque down way low. You would do best to take a Chevy bellhousing and trans with it. Look into kits for this transfer. I know they are made (I've seen a completed LT1 car or two.

dwhita6605 05-07-2007 04:24 PM

RE: this might sound crazy but....
 
its just hard to find a manual trans for it, right now it has an automatic mated to the 350...




nobuhiko takada 05-07-2007 09:13 PM

RE: this might sound crazy but....
 
i been pondering the sr20 swap, it seems i good choice, i would not rule it out due to small stock numbers, the thing about that motor is the vast aftermarket,

asfar as the v8 swap goes, im all about it, i wanna do it but the only site i found offers only ls1 kits, i cant afford a damn ls1.

anyone know of some other options for swap kits? also maybe somwhere to get decent deals on motors and trannys?

what about completly pimpin out the stock 2.5 with bigger injectors, intake, THE WORKS, with a nice nitrous kit? it might give some of you swapped guys a decent run,


Sheng 05-08-2007 09:24 PM

RE: this might sound crazy but....
 
The turbo tranny is sufficient to hold the power for a while, although don't clutch drop too much, there is a site for porsche hybrids
www.porschehybrids.com
and the place for the kit *although discontinued*
www.renegadehybrids.com
Good luck with your hybrid i've only heard good things, only problem is expense


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