3.9 Litre 986 S ... ? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

The Radium King · 09-20-2010, 09:29 PM

Steve Tinker · 09-20-2010, 10:05 PM

AutoFarm has an enviable reputation in the UK - not unlike Flat6 or L N Engineering in the US. Not cheap, but good.
Now I really fancy a 3.7 or 3.9 engine in my Boxster S - but I would have to learn to drive it properly......

ekam · 09-21-2010, 05:44 AM

There are already a few 986 with 3.8 conversion done by FVD...

Cloudsurfer · 09-25-2010, 04:35 PM

These are built motors, not a bone stock M97 3.8. I have a 3.6 based 3.8 in my car, and it hauls

Supposedly now someone has figured out a way to get to 4.0....

Clarky_X · 10-04-2010, 05:30 AM

Hi, I am very interested in finding out more about autofarm 986 conversions. Anyone got one please post your comments / reviews. I am seeking a 52 plate 260 manual with a view to going up from 3.2 in the future. I was initially thinking FI or other mods but have heard such bad press, so now I'm thinking either just a straight engine swap, but finding an engine for sale seems to be an issue, or going for a conversion by a reputable UK firm.

Jake Raby · 10-04-2010, 07:52 AM

We've had a 4 liter for 18 months now..

Its nothing new, but it can only be made reliably (IMHO) from a very rare, very late M96 engine. Not every core has the proper material to reliably allow for a bore of the required size.

The difference is the LN/ FSI way of doing this doesn't impact the capability of the coolant to circulate around the top of the cylinder, the hottest portion of the cylinder.

About 24K will net 450HP N/A

Lobo1186 · 10-04-2010, 12:27 PM

how reliable would that 450 hp motor be? would it be higher revving also? would that 450 be at the wheels? and would a turbo on top of that be possible? (for future power if ever wanted)

Jake Raby · 10-04-2010, 12:49 PM

Its comprised of all the same overkill components as those developed before it.. We didn't take any risks with the engine design wise, like thin cylinders and etc so the reliability should be the same... But time will tell.

The 450HP is at the flywheel. A turbo would be possible, in fact I am working on one of them now with boost.

Everything I build is always built with reliability in mind, even something like this 4 liter. We could go bigger, but at the loss of structural integrity that could lead to reliability issues.

Lobo1186 · 10-04-2010, 01:19 PM

see it intrigues me because that is what I want reliability and power (who doesnt) I am even considering going to a non porsche power plant.

but, keeping a pcar plant and still making 450ish hp reliably is good to hear. sure 24K isnt but you gotta pay to play. and when you play in the porsche world the prices is much higher.

but you say that is only with a rare block? how how much would that cost even if you were able to find it?

Jake Raby · 10-04-2010, 02:10 PM

We know what to look for, others haven't identified this yet (and probably won't) so the cases aren't that expensive... I have one prepped and ready to go, real Nickies liners already inserted and pistons ready to rock!
I'll post some pics tomorrow.

Jake Raby · 10-10-2010, 08:03 PM

Quote:

Why should one of these motors not see the street? I was under the impression that one of these motors is just as reliable and strong as one of your normal rebuilt M96 motors (IE 2.5, 2.7 and what not)

Mostly due to emissions constraints and sub-systems that are required to develop this level of power.

I'd much rather say the engine is for track use only as to deal with the probable fall-out if a street version of it would not pass an emissions test.

All of my other engines are dual purpose and very applicable to the street, this 4 liter just isn't. Competitors won't tell you this.

Lobo1186 · 10-10-2010, 08:26 PM

Quote:

Originally Posted by Jake Raby

Mostly due to emissions constraints and sub-systems that are required to develop this level of power.

I'd much rather say the engine is for track use only as to deal with the probable fall-out if a street version of it would not pass an emissions test.

All of my other engines are dual purpose and very applicable to the street, this 4 liter just isn't. Competitors won't tell you this.

understandable, luckily for me I am not bound by emissions testing.

So if emissions are not involved with any of your plants does that open the doors as it were to making more power since you dont need to work under those restraints?

also, just for the sake of knowledge what are the subsystems that are affected by the motor of that displacement. does it have to do with the motor itself?

Jake Raby · 10-10-2010, 08:53 PM

Engines are combinations.. Those that are efficient and effective have the smartest combinations.

If you are not bound by emissions, we share something in common and we should be very happy about this..

When asking the engine to produce this much power most of the OEM components have to go, including injectors, intake plenum and etc. The off shelf headers that are sold by those who sell sound and bling also won't work, we are making our own headers for this engine and their is no way to make it "quiet".

If seriously interested I can give you more info via telephone, my competitors review my posts here and other places to educate themselves, so I must watch what I say.

Lobo1186 · 10-10-2010, 09:11 PM

I understand, operation security as it were is always a good thing

!

I may be heading over to the eastern seaboard in the near future. If I can Ill try to call in tomorrow I would like to get all my options so i can layout a good buildplan for my car.

thanks for the help and hopefully ill be talking to you in the near future.

Jake Raby · 10-11-2010, 08:43 AM

Great, I look forward to chatting with you. Dean, my operations director will schedule a time that we can talk, I generally do these chats on Wednesday evenings

nefarious986 · 12-15-2010, 03:06 AM

Hey Jake,

I'm a little confused by the options available via your site.

I see two 450HP options. Both seems based on the 3.6L engine, but two different SKU # ( SKU162491111 and SKU1615911 ) and different prices so I'm assuming they're different products. Perhaps though it is the same product / engine, but just different application ?

SKU1615911 specifically says not street legal, while SKU162491111 doesn't.

If I wanted a 450HP street legal 986, would it be possible to put the SKU162491111 engine in ?

Thanks

autodoctor911 · 12-20-2010, 04:11 PM

why not take a 2009 911S motor and install a standard 911 crankshaft with the appropriate rods or pistons to get a 3.996L. I have seen MA101 motors for $16k on ebay, and they already make 385 HP stock! add 5% displacement by stroking it to 4.0L. I also believe that porsche has left some power on the table with the new dfi motors. with 12.5:1 compression and the fuel being directly injected, alowing for the posibility of fuel timing and multiple injections per stroke, there has to be some room to play with, without even needing to increase airflow. I am really looking into a diesel 3.0 from the european cayenne for mine though. I want 1000lb feet of torque! Ha Ha! the engine can come from a toureg or Q7 in a scrapyard here. add some boost, and the 29,000 psi bosch diesel injection is capable of adding plenty of fuel. if the block can take it, then getting the power should be no problem, if someone can crack the code for the reprogramming of the factory controller, or start from scratch, and build a stand alone controller that can also interface with a boxster abs and traction control. you will need the traction control!
and oh yeah, it only weighs 416lbs fully dressed. about the same as a 2.5 or 2.7!