Menu toggle

Building a 400bhp+ 2.5 ltr 944 Turbo

PSH

PCGB Member
Member
Good day all


Well I've been threatening to do this for a while so about time I got started, I will give advance warning here that this build will not be a quick build, as well as the car I'm also in the middle of major house renovation and garden landscaping, plus my main hobby of live steam model engineering , they all take up valuable time which when you get to my age ( 52) you start to realise that you just don't have enough years left to do all that you wish, so although I'm stating my planned route of build here things may and probably will change along the way. First, a little history of the car spec to date, I think most here know now that on a good day my car had a power output of 368 bhp and 382 lb torque at the flywheel, rear wheel figure was 326 bhp. She did as some here will know loose some power in more recent times which stumped me for a while but eventually I found the cause which was due mainly to my lack of understanding on valve movement/hydraulic tappets and nothing to do with the car or it's components, I won't be making the same mistake again..:)

The car is a 1986 model that I've owned for over 14 years and like most started off with light mods that progressively grew.

First mod (1998) was a Lindsey boost Enhancer, not a real power gain but it felt quicker

Next (2000) was a Lindsey dual port wastegate with manual boost controller, this was then mapped on a dyno by Wayne Scofield, resulting power 282bhp/282torque.

Followed by (2005) 368bhp/382torque

So what do you need to make a reliable 368 bhp

Block remained standard, it's an 86 car that means forged internals and crank designed for over 500bhp, later cars used the same crank but not forged components.
Lindsey Stage 2 Head with ceramic exhaust coating and machined valves for greater flow, all ports polished and map flowed.
Cometic head gasket
Lindsey Super 61 Turbo
Siemens 55lb injectors
Lindsey Dual Port wastegate
New standard Hydraulic Tappets
Manual boost controller
NGK Iridium Plugs
Magnecor 8.5mm Red Leads
150mm K&N cone filter
Vitesse MAF with piggyback system
Intercooler: standard
Bailey Motorsport DV30 re-circulating valve
Exhaust: standard
silicone vac lines
Innovate Air Fuel Ratio meter/gauge
Adjustable fuel regulator
8 Hours mapping on a dyno at Chip Wizards Rochdale by the maestro himself Wayne Scofield. Car was set to run on 95 RON ( for safety) at 17psi. For those not in the know for every extra RON grade used you can safely increase the boost by 2 psi, so if I had requested the car set for 98 RON the boost could have been increased to 23psi and be just as safe, or so the theory goes ,of course the power would have been a lot higher, back then I was a little scared of going to far, so played safe, today I'm far more confident in the engines capabilities although I still do not intend to use all of the boost available.
Note: If I've forgotten anything I'll add it later

Now before I get started on the new build some things were added to the old spec but never put on a dyno to remap.

Janspeed twin rear exhaust section
Piper Ram intake system, custom install
Apex-i AVC-R electronic boost controller
Engine loom fully rewired using Lindsey components and covered in 1200 degree sheaving.
All sensors renewed
Dump to atmosphere Cosworth type dump valve
Stepper motor boost gauge with record
89' Turbo gearbox with LSD

I think that's covered most of it, I haven't gone into brakes and suspension , I think this intro is long enough I don't want to bore you guy's on the first page now do I...:) I will add though that as far as bodywork is concerned the car remains standard.

Ok, so plans for this build, first stage, items marked with star already acquired

Block: bored/skimmed out to 101mm *
Con-rods to remain unchanged although will be checked for balance, whilst researching the options the general consensus is that you can't beat the original Porsche forged items as used for the Turbo cup cars. As a point of interest I've read that the 83 N/A 944 has the same rods, strange.*
Pistons: IASA 101mm full race spec forged pistons with extra machined grove below the first ring, this allows a far higher boost without risk of blow by past the rings.*
IASA gudgeon pins*
Crankshaft machined undersize 0.25mm , both main and rod journals*
Raceware Head stud kit*
Raceware Main stud kit*
Raceware rod stud kit*
Genuine Porsche 0.25mm oversize Main/rod bearings*
Crankshaft scraper*
replace, oil pump/water pump/belts/tensioners/pulley's
Lindsey lightweight billet flywheel
Lindsey stage 2 clutch, 6 paddle
Speed Force Racing Stage 2 large intercooler
Speed Force racing oil cooler
Lindsey stage 2 head, rework valves to F1 spec hemisphere profile
Lindsey Turbo super 61 rebuilt
Vitesse + V-flex MAF for ignition timing
3" custom made Magnaflow free-flow exhaust including the all important turbo downpipe*
Of course a lot of what is already on the car will be reused after a good clean or rebuild where needed
last but not least the all important remap, by Wayne of course

edit: add Vitesse wasted spark to list

Planned second stage:

Stand alone EMS, not decided on which yet although inclined towards the TEC3-R EMS but need a little more research before commiting
Speed Force Racing stage 2 headers including cross over pipe, 3" turbo downpipe, 3" test pipe and 3" back box.

Ok I think that covers what's planned and what came before , as stated this will be a long process but I intend to be very heavy with pictures to help others both with building modified 944's but also as a picture reference of the 944 engine's workings that may make things easier for others in regards to general servicing on the 944.

I was going to post a few pictures of empty engine bay and partly stripped block but seem to be having an issue with photobucket just now but will try again later today, for now at least details of intent have been given which took me some time as is was.

Feel free to make any comments or suggestions good or bad, this thread is mostly aimed at helping others like mined to myself and hopefully help them avoid possible future mistakes.

Needless to say... more to come..:)

Pete
 
Ok photobucket now behaving First Pic of engine bay before removal of short block, most other parts already removed except Turbo

catenginebay1-1.jpg


Next, once the engine was out it was time to clean everything up, crossmember was removed, cleaned, fitted with new 968 rear wishbone mounts, steering rack cleaned and checked, bay cleaned and detailed, intercooler housing resprayed and bottom mounts removed ready for new bigger intercooler.

carenginebaycrossmember-1.jpg
carenginebayrepainted.jpg
picture of short block before stripping down.
carengineblock.jpg
Pete

 
Will be interesting to follow your progress, good luck with this project! What compression ratio with these pistons?
 
Looking forward to reading this as it develops. One word of advice - ditch the house and garden refurb, and GET ON WITH THE ENGINE MAN! [:D]
 
ORIGINAL: TTM Will be interesting to follow your progress, good luck with this project! What compression ratio with these pistons?
I'll have to get back to you on this one, for some reason I can't find the data sheet, IIRC it wasn't to far away from standard, maybe someone more in the know can work it out. 101mm dia and the dish holds 26cc. I'll try to find the sheet for IASA's stated CR anyway. Pete
 
ORIGINAL: Diver944 Looking forward to reading this as it develops. One word of advice - ditch the house and garden refurb, and GET ON WITH THE ENGINE MAN! [:D]
now come on Paul, being a married man yourself you know that I have as much chance of doing that as winning the lottery...:) Pete
 
a little work done on the block tonight and a couple of problems to deal with before reassembly can begin Here's the block after being re-bored , the mains ladder frame is still in place, this is needed for maintaining structural strength during the re-bore process. Note the seized 6mm studs in the front that hold the water pump. There's also a sheared 10mm stud from an engine mount support, all of these have to be removed.
IMG_2778.jpg
The water pump studs have to be removed as the threads have corroded away, the stud in the next picture was removed using the two nut system as the thread was just about strong enough to do this, the others are two far gone and two have since snapped after hours carefully trying to remove them using various methods and lots of penetrating spray that had been soaking for a few days, obviously these will now need drilling out, that's for tomorrow. The large IIRC 10mm stud in the middle of the block is in good condition so will be left alone.
IMG_2780.jpg
All of the other threaded holes in the block , 6,8,10mm have been re-tapped using suitably sized bottoming taps, the same will be done to the main and head bolt threads to ensure I get the correct torque setting during re-assembly, this is important.
IMG_2779.jpg
sorry about photo quality, some have been taken in poor light Pete
 
Wow pete......you have yr hands full there good luck with the project !(at least you will save on labour cost :) )
 
I love these engine build threads. I'm always impressed with the level of detail and expertise that you gents possess, but mostly the passion that quite clearly you all have for these great cars of ours. I'm curious Pete, is the knowledge you have self taught or from work? Spence
 
ORIGINAL: Black Beauty I love these engine build threads. I'm always impressed with the level of detail and expertise that you gents possess, but mostly the passion that quite clearly you all have for these great cars of ours. I'm curious Pete, is the knowledge you have self taught or from work? Spence
a bit of both Spence, I've worked on cars since a very young age, bikes too. In my early 20's I did a diploma in HGV engineering but that's my only qualification in this field. I work as a technitian in the film industry which involves a lot of engineering work, it also installs in you that anything, no matter how daunting a task, can be built. Because of this I have a fully equipped workshop at home and anything I don't have my son, who is a proper mechanic, can loan it to me. I also have his expertise to full back on if I'm unsure of anything. Pete
 
Subscribed and best of luck Pete. Always enjoy these builds. A couple of things I'd suggest. I'm not sure about the Turbo Cup Rods but the stock rods are pretty strong yet quite a lot heavier than aftermarked ones available now. Also, they're over 25 years old if you're using your originals. When you have Arrows available in the UK, why not? Even Wossner is a good choice without getting too expensive. I'd be a bit wary dealing with SFR. I've dealt with them and have had big delays. This is also an open fact on Rennlist. Also their S2 headers won't fit an RHD car without major mods due to our steering shaft. I know where you can get a set of equal length headers for an RHD car if you are interested. I have a set on my 3L motor (not in car yet) and I know he had another set available recently. Email me if you want more details.
 
ORIGINAL: 333pg333 Subscribed and best of luck Pete. Always enjoy these builds. A couple of things I'd suggest. I'm not sure about the Turbo Cup Rods but the stock rods are pretty strong yet quite a lot heavier than aftermarked ones available now. Also, they're over 25 years old if you're using your originals. When you have Arrows available in the UK, why not? Even Wossner is a good choice without getting too expensive. I'd be a bit wary dealing with SFR. I've dealt with them and have had big delays. This is also an open fact on Rennlist. Also their S2 headers won't fit an RHD car without major mods due to our steering shaft. I know where you can get a set of equal length headers for an RHD car if you are interested. I have a set on my 3L motor (not in car yet) and I know he had another set available recently. Email me if you want more details.
Hi Patrick Thanks for the input, the post 86 stock rods have been known to through over 350bhp, not sure about weight difference, whereas the earlier forged items have been rigorously tested by Porsche to I believe +500bhp , I believe these are the same rods as used in the Le Man cars that ran a solid 24 hours at 420bhp, detuned a little from the 450bhp ( yes I know they used a 16v head but believe the block remained the same) that the cars had been set up for and of course later raced in the turbo cup cars ( I stand to be corrected if I have any of this wrong). I have done a lot of reading on this and seems that the experts out there ( what ever an expert is) say you can't beat the OEM forged rods, admittedly I haven't looked too closely at the weights for the different options open to me. In doing this latest round of mods one thing is clear in my mind, I want reliability more than all out power, the car was already very close to 400bhp and would probably have achieved that with a larger exhaust and remap alone. Yes I can gain a little more power from reducing crankshaft mass components, which I shall be doing anyway using a crankshaft scraper and lightened flywheel, race pistons etc but I guess it's a case of where do you stop and at what cost? I'm aware of SFR's past history on supply which I believe was mainly with Tial dpw's but that was with 'out of stock' items that had to be remade, however the delay was IMHO unacceptable and hopefully will not be repeated. I have spoken to Tim at SFR but of course you can never be sure, he seems a nice enough guy but I'll certainly report any problems here if I have them, luckily this is a long build so if any delay is experienced I have plenty more things to get on with. I'm also aware of the fitting problem regarding SFR's stage 2 headers on rhd cars, in fact Paul ( diver944) mentioned this to me at the last Ace Cafe meet and it's something that I'll need to look into, I'm not to worried by possible alterations required, it's my job to work on prototypes so not deterred with a little fettling. However I note your kind offer of assistance in regards to what you have had made for your car for which I'm most grateful. I will get in touch if I go that route, for now it's not high on the list as it's a second stage item being considered for after the car is back on the road and fully run in. regards Pete
 
My MAP induction pipe came from SFR and the service was so poor as to be almost laughable. Apparently, at one point the product had been posted and was being held up in delivery, but then later it hadn't been produced because they needed to agree how many pipe connections I wanted. They make various noises that sound right at the time but you only eventually get the product shortly after having given up all hope of seeing it in this life time. Order well in advance of actually needing it.
 
I don't understand the use of stock rods either. Eg Pauter rods will be stronger, lighter and new. I can't say I could still be impressed these days with whichever rod testing Porsche possibly did some 30+ years ago.
 
ORIGINAL: TTM I don't understand the use of stock rods either. Eg Pauter rods will be stronger, lighter and new. I can't say I could still be impressed these days with whichever rod testing Porsche possibly did some 30+ years ago.
I do hear you and note the advice, I have to draw the line somewhere in regards to cost but more importantly the advice out there from those who have gained more power output than I plan to is to keep the forged rods? I appreciate the argument for 30+ years testing and buying new but as the saying goes the 'proof is in the pudding'. The rods in question 944.103.110.0RARST have proved themselves more than capable of containing high bhp under the most strenuous conditions possible, ie 24hr Le Mans and the Turbo Cup Championship. I think they'll be fine for me who is probably getting too old to fully use the power anyway....:) Pete
 
ORIGINAL: John Sims Can anyone remember what gave way on Fen's car? Wasn't that after market rods?
It was a rod for sure, not sure if after-market or later Porsche though, perhaps others will know? Pete
 

Posts made and opinions expressed are those of the individual forum members

Use of the Forum is subject to the Terms and Conditions

Disclaimer

The opinions expressed on this site are not necessarily those of the Club, who shall have no liability in respect of them or the accuracy of the content. The Club assumes no responsibility for any effects arising from errors or omissions.

Porsche Club Great Britain gives no warranties, guarantees or assurances and makes no representations or recommendations regarding any goods or services advertised on this site. It is the responsibility of visitors to satisfy themselves that goods and/or services supplied by any advertiser are bona fide and in no instance can the Porsche Club Great Britain be held responsible.

When responding to advertisements please ensure that you satisfy yourself of any applicable call charges on numbers not prefixed by usual "landline" STD Codes. Information can be obtained from the operator or the white pages. Before giving out ANY information regarding cars, or any other items for sale, please satisfy yourself that any potential purchaser is bona fide.

Directors of the Board of Porsche Club GB, Club Office Staff, Register Secretaries and Regional Organisers are often requested by Club members to provide information on matters connected with their cars and other matters referred to in the Club Rules. Such information, advice and assistance provided by such persons is given in good faith and is based on the personal experience and knowledge of the individual concerned.

Neither Porsche Club GB, nor any of the aforementioned, shall be under any liability in respect of any such information, advice or assistance given to members. Members are advised to consult qualified specialists for information, advice and assistance on matters connected with their cars at all times.

Back
Top