dfi engine common parts,3.4 to 3.8 conversion!

[itsybitsy]

http://www.pistonheads.com/gassing/topic.asp?h=0&a...
as per the post above I looked into the part numbers of the different engines and the bottom end and con rods are common to all n/a cars.so my thinking is if you want to turn your 3.4 into a 3.8 is it a case of 2 new blocks or maybe bore the existing block out the 3.8 pistons and rings plus the 3.8 cylinder heads .i am assuming you can mate the block to the crankcase for different models as the bottom end is common to all but on the PET(parts catalogue) it shows the 2 halves(crankcase and block) as one part number.am I missing something or is this an expensive exercise to gain more hp ie 65 hp for my spyder

Edited by itsybitsy on Tuesday 30th July 10:01

[sootyvrs]

Perhaps speak to a Porsche specialist like Specialist Cars in Malton who can do modifications e.g. Cayman GT3 conversions

http://www.specialistcarsltd.co.uk/vehicle/special...

I assume they should have knowledge of the Porsche internals

[itsybitsy]

sootyvrs said:

Perhaps speak to a Porsche specialist like Specialist Cars in Malton who can do modifications e.g. Cayman GT3 conversions

http://www.specialistcarsltd.co.uk/vehicle/special...

I assume they should have knowledge of the Porsche internals

the reason I posted this was many caymanR/spyder owners crave more power and like myself hoped Porsche would have given us more on launch or created a gt3 like version.my thinking is if you had your local opc replace the said parts to 3.8 block,pistons/rings and cylinder heads we would then have the car we wanted from them in the first place without going to a complete new engine which is not required to turn your 3.4 into a 3.8 and being Porsche parts plus done by local opc the warranty should remain intact because you have only upgraded your engine.
it is certainly something to consider in the future.

[itsybitsy]

lets say it can be done and I am right in my thinking plus the costs are less than 7k to do assuming parts are 5k and labour 2k pretty cheap way to get 65 hp

[ChipsAndCheese]

Might be worth having a chat with Autofarm, as they offer 3.7 and 3.9 litre conversions on Boxsters and Caymans. I'm not sure if they offer this for the later dfi engines, as their project Cayman was a gen1 S, but they might be able to advise on the feasibility of doing it.

[itsybitsy]

ChipsAndCheese said:

Might be worth having a chat with Autofarm, as they offer 3.7 and 3.9 litre conversions on Boxsters and Caymans. I'm not sure if they offer this for the later dfi engines, as their project Cayman was a gen1 S, but they might be able to advise on the feasibility of doing it.

but I am talking purely bolt on parts and not a conversion like autofarm or other specialists as the 2.9 internals less the pistons,rings,bores,cylinder heads are common to a 3.8.

[ChipsAndCheese]

itsybitsy said:

but I am talking purely bolt on parts and not a conversion like autofarm or other specialists as the 2.9 internals less the pistons,rings,bores,cylinder heads are common to a 3.8.

Even so, being one of the specialists who have dabbled in modifying Porsche engines I would think they would still be well placed to advise you on the feasibility. They are a friendly bunch there and I found them to be happy to chat about anything Porsche.

[itsybitsy]

anonymous said:

[redacted]

the thing is if Porsche built a 3.8 caymanS or gts cayman with say the 3.6 engine they would charge as much as a standard 911 or up to £15k more for an engine built from the parts bin which would cost no more to build than a 2.9

[Trev450]

This is something that I've been trying to gather information on also.

I agree with the comments that it could potentially be a very expensive way of achieving an additional 60 ish bhp, but could be a viable option if your engine required a rebuild due to bore scoring for example.

[edc]

Would it not be cheaper to do the exhaust manifolds/exhaust/intake/larger throttle body/remap combination instead. You won't get the capacity increase but if it is anything like the 986 or 987 then you can get a 10-20% power hike.

[itsybitsy]

Trev450 said:

This is something that I've been trying to gather information on also.

I agree with the comments that it could potentially be a very expensive way of achieving an additional 60 ish bhp, but could be a viable option if your engine required a rebuild due to bore scoring for example.

hopefully borescoring is not an issue on the dfi lump.i agree with cmoose but we always want more power from our cars and its what Porsche should have done with the cayman/boxster engines sometime ago.
what I was really trying to get across is the engines share common main components.the 991 gt3 is common to the 991s albeit with uprated crank,conrods,pistons,cylinder heads and most likely nikasil bores which in turn could be fitted to any other engine in the dfi range unless there has been extra machining on the crankcase for the uprated crank?
if borescoring were to occur at high mileage then any with a 3.8 could upgraded to a gt3 nikasil /bore and pistons/rings unless the pistons only mate up with the gt3 cylinder head.
this is all pure speculation and I am no engineer/mechanic but it is food for thought and offers dfi engines more than just a remap and exhaust but using genuine Porsche parts.

[Slippydiff]

itsybitsy said:

lets say it can be done and I am right in my thinking plus the costs are less than 7k to do assuming parts are 5k and labour 2k pretty cheap way to get 65 hp

Your average OPC charges what ? Somewhere between £125-150 an hour, and you reckon they can remove an engine, strip it completely, rebuild it using the parts required to increase its capacity to 3.8, refit it into the car and renew all the relevant fluids, filters etc and re-configure the ecu to take account of the extra Hp, that doesn't allow for any differences in the exhaust or inlet system either.

You haven't really thought this through have you . . . . .

[mollytherocker]

itsybitsy said:

the reason I posted this was many caymanR/spyder owners crave more power and like myself hoped Porsche would have given us more on launch or created a gt3 like version.my thinking is if you had your local opc replace the said parts to 3.8 block,pistons/rings and cylinder heads we would then have the car we wanted from them in the first place without going to a complete new engine which is not required to turn your 3.4 into a 3.8 and being Porsche parts plus done by local opc the warranty should remain intact because you have only upgraded your engine.
it is certainly something to consider in the future.

I think you have no chance of even an opc agreeing to do this, never mind warrant it!

[mrdemon]

Better selling your engine as whole unit and buying a gts engine with 405 Bhp from a write off.

That would give you a 85bhp gain and only cost about 5k plus fitting. (Fitting is the big price imo) could be another 5k.

Say 10k to buy the new engine 2nd hand, but you should get 5k for your old one.

But these cars don't need any more Bhp imo, they drive so well the r and Spyder any thoughts I had of more power have gone.

Just fit a few cheap bolt on parts and get them to 350bhp and drive them.
You can easy get them to 1200kg imo and with 350 Bhp not much is staying with one on track.
Look at 964 Bhp or 993 RS Bhp , do you need 400bhp in a car which drives so well ?

[itsybitsy]

Slippydiff said:

itsybitsy said:

lets say it can be done and I am right in my thinking plus the costs are less than 7k to do assuming parts are 5k and labour 2k pretty cheap way to get 65 hp

Your average OPC charges what ? Somewhere between £125-150 an hour, and you reckon they can remove an engine, strip it completely, rebuild it using the parts required to increase its capacity to 3.8, refit it into the car and renew all the relevant fluids, filters etc and re-configure the ecu to take account of the extra Hp, that doesn't allow for any differences in the exhaust or inlet system either.

You haven't really thought this through have you . . . . .

I have no idea of the costs involved and this was purely quess work.the whole point of this post is that some of the main parts ie crankshaft,conrods are common to all dfi engines.i agree with mrdemon that is most likely cheaper just to swap engines.but if your engine for what ever reason decided to damage its bores/pistons/heads then at that stage you could increase capacity using genuine Porsche parts from the larger engines at not much extra cost if you had no warranty instead of replacing like for like.
this post also shows how easily and cheaply Porsche could give us the caymanR/spyder or dare I say it cayman gt3 some of us would like to see with not just more hp but more importantly the extra mid range torque a larger engine gives you which the boxster/cayman have always lacked.

[itsybitsy]

mollytherocker said:

I think you have no chance of even an opc agreeing to do this, never mind warrant it!

I believe my local opc was one of the first to transplant a 3.8 into a brand new cayman.
as for the warranty I do agree but you are using genuine Porsche parts and just upgrading from say a 3.4 to a 3.6.if you retro fitted the x51 to a 911 at a local opc would not your warranty remain intact
it would be easier if Porsche offered us factory performance upgrades of the shelf(like the x51 but with capacity increase for boxster/cayman) which is a possibility with the dfi but will never happen

[itsybitsy]

mrdemon said:

Better selling your engine as whole unit and buying a gts engine with 405 Bhp from a write off.

That would give you a 85bhp gain and only cost about 5k plus fitting. (Fitting is the big price imo) could be another 5k.

Say 10k to buy the new engine 2nd hand, but you should get 5k for your old one.

But these cars don't need any more Bhp imo, they drive so well the r and Spyder any thoughts I had of more power have gone.

Just fit a few cheap bolt on parts and get them to 350bhp and drive them.
You can easy get them to 1200kg imo and with 350 Bhp not much is staying with one on track.
Look at 964 Bhp or 993 RS Bhp , do you need 400bhp in a car which drives so well ?

yes you increase bhp higher up the rev range by an ecu flash exhausts etc but the torque remains the same.
even the new 991 3.4 internals must be the same as the boxster/cayman but it must have a head job to increase the torque and hp along with the different ecu/intake/exhausts to get the extra 20-25hp

[mrdemon]

Just change the manafold imo

These give a torque increase.

A GT3 cayman would be a mistake in my eyes, I sold my GT3 for a reason as did my mate.

Look at 964 and 993 owners and Bhp.
Look at Lotus Bhp

Great driving cars don't need massive Bhp .

It's taken me 44 years and 50 cars to find his out lol.

Get the geo right and the Spyder and R are amazing driving machines for the UK.

[khushy]

sounds like "Trigger's New Broom" to me!

(@ 1 min)

http://www.youtube.com/watch?v=s1VNNbSYdt0

khushy