2.5l to 2.7 swap
03-12-2013, 11:24 PM
#16
If your on a budget forget the S2/968 swap.A running 968 motor with service done up to date will be in the $4k-$6k range & the S2 won't be far behind.Also when doing such a swap on a 2.5/2.7 NA suspension will also have to be look at,peoples doing such a swap usually go with the 951/S2 suspension specially the 968 swap.A 968 stock has 236 HP & the 944 NA simply doesn't have the suspension to cope with such HP.Sure some will argue that you can get away with it, personally I don't believe so.Meaning more money involve in such a swap. Btw beware of the 2.5/2.7 swap ,the 2.7 is a one year only production motor & you migth find out that some parts for it are more expensive & hard to find than the 2.5,just an example do a search for a good 2.7 use head & see how many you can come up with.
03-13-2013, 12:07 AM
#17
Drifting
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Errm come on now ernie, can you educate us on the difference? because short of the brakes i can't really think of one. The s2/968 have barely more spring rate up front, the same t-bars in the back (23.5mm) and suspension setup is mostly the same. Bigger sways? All easy to change...
03-13-2013, 01:14 AM
#18
Before a newbie to 944s NA goes & spend $1,695.00 could ligth us up on how by just droping a set of euro piston (no mods need) you will achieve a 14 HP gain.It is a claim by the seller or it's a Dino proven fact.Btw anyone here has done this & if yes did your 2.5 NA motor gain 14 HP from such a mod.
Clarks Garage link to 944 specs:
http://www.clarks-garage.com/tech.htm
Picture of the piston differences:
Last edited by Chunkerz; 03-13-2013 at 01:34 AM. Reason: stupid auto correct
03-13-2013, 08:24 AM
#19
Nordschleife Master
1983-1987 2.5liter US spec 944 engines have 150hp. The compression ratio of the pistons is 9.5:1. The 2.5 liter ROW 944 engines have 163hp (except for the 1988 engine). The compression ratio of the pistons is 10.6:1. All you do is remove your horrible US pistons and drop in some super awesome euro pistons and ta-da! You just gained 13hp! You do not need to modify the head, intake, block, rods, crank, injectors, AFM, DME, etc. Higher compression= more power.
Clarks Garage link to 944 specs:
http://www.clarks-garage.com/tech.htm
Picture of the piston differences:
Clarks Garage link to 944 specs:
http://www.clarks-garage.com/tech.htm
Picture of the piston differences:
One of my engines has them fitted but I had them fly-cut to eliminate the interference (valve/piston clearance) then took a little off the head, so I'm at about 10:4cr and with a cat delete. One day I'll get it to the dyno.
03-13-2013, 10:38 AM
#20
Three Wheelin'
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I have found very little info regarding the differences in the 2.7 vs 2.5 It can't just be pistons...unless they are a larger bore, how do you get to 2.7? It is either the crank or rods that is getting it to 2.7.
All info I have found says 163 hp, but only state "significant" increase in torque, though I have not seen any torque numbers. That could explain why someone (V2 I think) would say for daily driveablility, the 2.7 offers a noticeable increase in "umph".
Interesting discussion as I hear so little about these engines.
All info I have found says 163 hp, but only state "significant" increase in torque, though I have not seen any torque numbers. That could explain why someone (V2 I think) would say for daily driveablility, the 2.7 offers a noticeable increase in "umph".
Interesting discussion as I hear so little about these engines.
03-13-2013, 12:43 PM
#22
Drifting
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[quote=Chunkerz;10296472]1983-1987 2.5liter US spec 944 engines have 150hp. The compression ratio of the pistons is 9.5:1. The 2.5 liter ROW 944 engines have 163hp (except for the 1988 engine). The compression ratio of the pistons is 10.6:1. All you do is remove your horrible US pistons and drop in some super awesome euro pistons and ta-da! You just gained 13hp! You do not need to modify the head, intake, block, rods, crank, injectors, AFM, DME, etc. Higher compression= more power.
Thanks Chunkerz for the clarification.
So what we are talking here is a lot of money invested versus low HP gain taking parts/labour in consideration.
Thanks Chunkerz for the clarification.
There is more power to be had with the Euro pistons and there are plenty available used across the pond, but all the extra power quoted doesn't come just from the pistons. Most of the Euros didn't have cats and run on higher octane fuel plus I think the dme tune is different and the exhaust manifold also flows better. Still those pistons alone are probably good for 8-10hp.
One of my engines has them fitted but I had them fly-cut to eliminate the interference (valve/piston clearance) then took a little off the head, so I'm at about 10:4cr and with a cat delete. One day I'll get it to the dyno.
One of my engines has them fitted but I had them fly-cut to eliminate the interference (valve/piston clearance) then took a little off the head, so I'm at about 10:4cr and with a cat delete. One day I'll get it to the dyno.
03-13-2013, 02:47 PM
#23
Nordschleife Master
I got the Euro pistons cheap while I was in England, under $100 for the set. Fly cutting cost me $25/piston and I was rebuilding the engine anyway.
03-13-2013, 03:16 PM
#24
Drifting
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Yes, 10hp though is a good gain for our engines, it's hard to get real power out of these things without spending $$$'s. Cheapest method to get any performance gains is to start dropping weight.
I got the Euro pistons cheap while I was in England, under $100 for the set. Fly cutting cost me $25/piston and I was rebuilding the engine anyway.
I got the Euro pistons cheap while I was in England, under $100 for the set. Fly cutting cost me $25/piston and I was rebuilding the engine anyway.
03-13-2013, 04:17 PM
#25
That's what I'm here for
03-13-2013, 04:59 PM
#26
Nordschleife Master
You got it - non interference, one less thing to worry about. The piston tops had enough metal to do this and the shop that did them had done this many times before. They just skimmed the head to make it level, The fly cutting didn't take much off the compression and I've had not issues with it. I even inspected the piston tops with a scope through the plug holes after a few k miles and saw no evidence of hot spots or carbon build-up at the cuts. I probably wouldn't do it on US pistons though, the compression is low enough as it is. At least the Euro's give you something to play with and keep you above 10.0cr
03-13-2013, 07:31 PM
#27
Track Day
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thanks all, because of simplicity and the budgets sake, ill probably just stick with the 2.7, my engine needs a rebuild anyway so why not upgrade for a bit more. i still have the rest of the car to upgrade and with a performance rebuild on a 2.7 i think itll be pretty fun.
03-14-2013, 03:21 AM
#30
Arominus, I saw that vid you posted too... I'm pretty sure the red car is the S and the green one is the NA. The green car is obviously early offset and the red one has D90's (not that it means anything but you know...) Interesting vid though I agree.
Its funny you guys say the 16v cars would be great with a supercharger... I just happen to have an Eaton M62 blower and turbo S bottom end laying around... I'm excited
I too am in favor of the 16v swap opposed to the 2.7. They rev to almost 7k and sound unreal as well. Slap an S2 intake manifold on there and you'd have quite a machine.
Also I'm not sure if any one straightened it out but the 2.7 motors share their block with the S2. Lower compression pistons + different crank = 2.7L. 104mm bore I believe...
Its funny you guys say the 16v cars would be great with a supercharger... I just happen to have an Eaton M62 blower and turbo S bottom end laying around... I'm excited
I too am in favor of the 16v swap opposed to the 2.7. They rev to almost 7k and sound unreal as well. Slap an S2 intake manifold on there and you'd have quite a machine.
Also I'm not sure if any one straightened it out but the 2.7 motors share their block with the S2. Lower compression pistons + different crank = 2.7L. 104mm bore I believe...