Porsche Enthusiasts Club Forum

I can see there's some good advice in here but you may like a bit more.
My motor is a touch under 3.1ltrs. It's from a 2.5 block that has been sleeved with dry liners and has a deckplate to help hold the open cylinders firm at the top of the block. We have very large 9/16" headstuds and have been running Cometic headgaskets since running with this motor. Actually we ran them successfully on the previous 2.5 stock-ish motor also. However we have been blowing these each time we go to the track so are going down a different path. (This is now a track only car btw) We have a lightened crankshaft, Arrow rods, CP pistons, big 49mm 8 valve head, big cam etc and run a GTX3582. Fully 'MoTeC'd' and run race E85 between 1.3 and 1.5 bar. We are hopeful of being able to run more boost once we've sorted the h/g issues. There is no sign of detonation so what is happening to cause the constant h/g issues? Head lift, block / head flex, stud stretch, soft Alu block...We are also only running a stock intake (extruded honed) with a 66mm Throttle body. Stock is 56mm. For sure the stock intake is a restriction but since we've seen over 500hp / 475ft/lbs to the wheels we have spent money elsewhere to find gains on the track. To clarify something else I saw in this thread. The stock n/a head does not flow 240cfm. It would flow basically the same as the stock turbo head give or take...

My point in telling you this is that I've kind of been there-done that. My advice to most people who are intending on major engine builds is to determine what you want from the car before you start spending money. If you really just want a fast road car that won't see any trackdays, or a limited amount of drive days on the track, I wouldn't go too crazy just for the sake of having something outrageous on the road. Even 400bhp is a fast road car especially if you have standard or mildly modified suspension and transmission. I had 325whp on my previous road / track car and it was plenty fast for the street. The car had other mods but was able to keep up and beat the quickest GT3's in our club racing competition back before the car was made into a dedicated track car. There is another guy in our club who runs a Vitesse stage iii kit on his stock 2.5 motor and also runs on par with the quick GT3's in our club.

You can achieve enough hp / tq with what you have and even increase the stroke for a bit more tq. Put on a more modern turbo and the car will feel brand new. I personally wouldn't be ordering half the LR catalogue. As far as an aftermarket ECU, there are better than Wolf BUT I think the proviso is support. Whatever you buy you need to have support locally, not Overseas. Buy something locally that you know you can contact them readily and they will support you after the purchase. This is crucial!

I think I would fall into the category of having 'been there-done that' to a greater or lesser degree.
My motor has about as much or more done to it as most 8v larger bore engines. We have achieved over 500hp / 465ft/lb to the wheels. (Think Jon might have mean 700Nm of tq btw!) We have a stock intake (extruded honed) and while it is definitely not ideal you can live with it on a street car. Ours is a track only car and possibly the fastest Porsche in Australia so you can certainly live with the stock intake if you don't have a viable alternative. I believe one of the main questions to answer is what do you want from you car? Is it road only or will it see a significant amount of trackdays?
Will you be upgrading suspension, brakes, driveline? I can see that you've mentioned some of those things but it's just a list of questions I suggest people ask themselves before diving in too deep. As I said, I've been there and wasted quite a bit of money along the way.

My take on this question:

- n/a head doesn't flow 240cfm.
- Don't go buying half the LR catalogue.
- 400bhp in a street 951 is plenty. 350bhp is still a fast car.
- If you have a big valve head just use it. The 16v motor is superior but more involved fabrication.
- All the cranks are generally the same...especially if you get them lightened.
- Only buy into an aftermarket ECU that offers quick and local support. Not from o/s vendor.
The Wolf isn't the best on the market but if you have an expert nearby then that will probably be better than another superior product that you purchase from o/s and have to work it all out yourself.

if people require fabrication to inlet/exhaust we have carried out this work for 16v turbo setup on this engine. using s2 exhaust manifold and turbo crossover pipe. and modified Toyota supra aftermarket inlet manifold cut to fit s2 inlet runners and throttle body flange.

get in touch via pm or email info@nicksonmotorsport.co.uk for further information.

thanks
nick

Great reply pat.

This sounds very much like Tim's intake Nick?

Why thankyou kind Sir.

Hi Pat, it is a blatent case of plagerism. Took tims design and have tried to copy it. If you look at the last pages of the thread 's2 repair' you can see some pictures of what we have tried to achieve.
I have much admired your car and the results you achieve in time attack. Not to shabby for a 25 + year old car !

It is very similar yes. But it is a system that seems to have worked for tim and every customer has a certain budget that needs to be met and this ensures costs can be kept to a sensible level rather than starting from scratch and fabricating a custom one off item that will cost much more to make.

If anyone else requires the fabrication work carried out there is no reason we cannot fabricate something entirely different and one off design. As long as they are prepared to pay for it! Same story with the exhaust setup which could be entirely fabricated from scratch, rather than just changing the crossover flanges to match s2 headers.

Just following the customers requirements in this case.

I will be fabricating a custom inlet and exhaust manifold/system for my 924 turbo project entirely from scratch which should be fun!

Simon, I hadn't seen your thread. I must confess to not getting on this forum on a regular basis and generally only look for the more modified car threads, so I must have missed yours based on the title. Nice work, although I too couldn't see the earlier pics.

I'd love to see your (Nick's) finished intake as I am still toying with something. I have vacillated between various options so much so that I've done nothing. Wish I had by now. Stock intake is not ideal although as we can get away with it we've left it on. Also the overall results for the car have been pretty positive so we've spent money elsewhere....but I'd really like to try something else without spending a ton of money. What you're doing sounds like it should be reasonably affordable?

Anyway, this is something for another conversation and not getting this thread off topic too much. Might PM you.

Aye, thank you all for all of you're reply's some great advice/tips !!

Sorry been a bit quiet, works crazy and getting the engine timings have slipped...

It's still going to be fun... it's just taking a bit longer...

So... twin scroll...

If say you were going for a twin scroll turbo for a 3.0 ltr 2.5 turbo bottom end mated to 968 head what are the options?

A mortgage . Seriously what are you aiming for, a track car or bragging rights ? As has been said 400 bhp is plenty for the road or occasional trackdays. Refresh your engine and use the 3.0 crank, if you can use that for more than a few seconds before backing off you're doing the wrong job. I would guess Turbotim's project would cost well into 5 figures if you had pay someone to recreate it and AFAIK it still isn't finished.
Talk in 3 months

To much talk off cost. Dreams are dreams get it done I want your head

Hey guys, hope all is well!!

So... after a long time waiting the dream engine build is not happening... would have been amazing... but guess it wasn't to be... if it does get built eventually though someone will be very happy I'm sure! Amazing people involved in the build (all there just needed assembly), silly power and torque and I'm sad it's not happening but I guess such is life...

So to cheer myself up I bought a mint 1989 2.7 lux, 90k on the clock and everything is like new (digital clock, dash, seats, body, steering, engine, paint, service history/paper work).



It really is a total show car! So clean and tight to drive and I see what they mean about the power delivery of the 2.7, it's a lot of fun... very very different to the turbo (oddly) but still great fun and quite rapid!

Still not 100% that WUF hasn't ruined me but it's nice to have an original as well as a beast!

WUF is in the garage having miles and miles of wiring removed ready to be rebuilt. Plan is strip all of the wiring/audio/(maybe weight) that is not needed (boot full so far), replace sensors and make sure everything is nicely set up and configured. After that a power run to see where we stand and then engine rebuild with or without further mods. 403hp (yes I know you all said it Pauly ;p haha) is pretty great (and probably more than I'll ever need) so we are refreshing to maintain this and look at the different turbo options (maybe as the massive kick is very very addictive!). Crying inside at being sensible though, the custom engine would have been ridiculously good... definitely not sensible but would have been fun...

Will post more on WUF as and when able, nothing changing on the lux though just keeping her tidy (she even has the original bill of sale and tax disc holder from the dealership!!!).

If the cylinders are worn/scored on WUF I'd have them sorted out and go ahead and fit that 3.0 crank with a set of forged rods and pistons, nothing more. That's what I would have done if I'd bought the car. If the cylinders are still good take off the LR75 and fit a smaller BB turbo. Either option would make it a much nicer road car. Post up a pic of that spare monster turbo Ben gave you .

Happy new year guys!!

2017 is off to a flyer new parts being ordered on Monday (only taken 10,000 years haha)...

Replacing the ECU for a more modern one and refreshing all of the sensors et al... Ditching some of the dials and installing a digital dash so that we have everything neatly in one place (no more looking to the radio area to check speed, need a 2nd speedo as larger wheels throw the standard one out)!! Modified head going back on, cylinders all looking good so getting her back up and running seeing where she stands before deciding what else is needed (turbo wise... BB ). Oh and getting rid of that bean can exhaust!!

Hopefully going to NEC on Thursday for the modified car event so who knows what I'll come back with, should be fun though...

Hope that you and your beasts are all well!