Building a 400bhp+ 2.5 ltr 944 Turbo

[PSH]

Hi Thom Nothing to update I'm afraid, if you remember I did post a thread when I was considering whether it was time to move on from Porsche ownership, I won't bore everyone with a rerun of what was said in that thread. I'm still undecided, if I was to sell the car I'd get far more money by breaking it considering the ten's of thousands of modified parts fitted, but I could never do that to the old girl, she has far too much life in her for that. So as some had suggested I've put her on the back boiler, the short block is finished and is safely stored in my workshop as I don't need to sell. The good news is I then found time to get on with my two live steam locomotive Pacific's, the smaller of which has just been granted her steam certificate and thus safe to run on the club track with the public in tow. This loco has now been dismantled ready for painting over the winter months so that she is ready for the beginning of the new public season next March. I will of course update this thread when the time comes. cheers Pete

 

[PSH]

Hey guys Bet you didn't think you'd see this thread again.. well as some will know I'm back on the car after my sabbatical building steam locomotives. They are still on the go but one's finished so now I have more time for the car, and the big one which is a long way off from completion but I now have all of the castings which cost me a small fortune so now can put money back into the car. Not much to report, but as a starter I now have my modified inter-cooler back from Tom at Augment Automotive, for which I'm most grateful, lovely job. So first picture for the return is to show the inter-cooler back where it belongs, it's been about 3 years since this gap was filled... far too long, I now have the front panel on too but not enough light for a picture.

Other things in the pipeline...today i ordered a new diaphragm and spring from Lindsey racing to give my DPW a new breath of life. I need to get a new valve seat fitted as the current one is cracked in 4 places and will never seal tight. On examination the seat seems to be the same size as the exhaust valves for which i have some spare seats around somewhere. I have the equipment to remove the old seat and machine the new seat's OD to match the old but I don't have the cutter to machine the valve seat itself so will see if I take it on myself or not... very tempted... Anyway, it's good to be back working on the old girl, updates may have big gaps but they will surely happen and the car will see action on the road again... Pete

 

[robwright]

Great to see you back Pete.

 

[Diver944]

Holy thread resurrection Batman!!!!! [] Nice to see progress being made once more Pete

 

[PSH]

cheers guys... believe me Paul I needed both Batman and his sidekick to find the thread....lol... Pete

 

[Eldavo]

Is this intercooler modification the one to the end tanks? I've looked into it myself but as usual most of the info was on RL and was contradictory to say the least. I'd be interested in your thoughts and findings when they become apparent.

 

[PSH]

ORIGINAL: Eldavo Is this intercooler modification the one to the end tanks? I've looked into it myself but as usual most of the info was on RL and was contradictory to say the least. I'd be interested in your thoughts and findings when they become apparent.

Hi Yes it's the modification to the left hand end tank ( as looked at in the picture) what's commonly called a stage 1 inter-cooler. I'm sure Tom can give you more details, he has graphs to show the improvements over the standard IC. In the past I've had trouble maintaining the power output that's shown in my signature, could never work out why, I had a number of possible issues, damaged valve seat and valves out of spec, scored bore due to a failed iridium plug ( don't use them) etc but one thing that was obvious on later dyno runs was an increase in intake temperature , ranging from 13 IT on the dyno runs for 368 bhp to 44 on the last dyno when the car only made 320 bhp. When I sent me IC to Tom to be modified it failed it's pressure test and thus scrapped, I quickly replaced it with another which is what has been modified now, the point is this certainly explained the increase in IT and would also be partly responsible for the drop in bhp, add the recently discovered damaged wastegate oh and the fact that the turbo had sucked the entire foam filter from the RAM intake through the turbo into the IC partially blocking it ( this BTW happened after the last dyno run) and things are beginning to make sense. The car will now make 400+, this I am of no doubt, it's certainly built to take a lot more, the question is how far do I go, after all I'm getting a bit old for the boy racer lifestyle.... time to slow down a little but that won't stop me from getting the best engine I can possibly build, it's a challenge and I love challenges.... Pete

 

[PSH]

morning guys.. not so much an update but an information post for others who may need to overhaul their own wastegates.. these are the service parts from Lindsey racing. Diaphragm: LR-WGD-101 @ $89.95 Wategate spring : LR-WGS-104 $ 15.00 total cost was £93 for the parts and £20 import/VAT duty Although the diaphragm currently on the wastegate hasn't failed it's very hard around the centre and will fail at some point in the future, so best to do this now while the car is in parts. I changed the spring for added security but on measuring the two springs they seem to be the same size although this isn't a test to see if the old spring has lost any strength, so again it's a 'do it while you can' scenario. I'm also considering machining a spacer to give the standard spring more resistance, same job as the Lindsey racing shims but an internal solution rather than their external one. I have now checked the valve seat and the standard exhaust valve seat for the head is of the same size, alas I don't have a 45 degree valve seat cutter so may farm this out although I'm looking into the cost of such a cutter first. Pete

 

[JagdHamster]

Awesome thread, Pete. Very informative and most interesting. I know from (many) previous turbo-charged models that standard intercoolers are very often the weakest link for enhanced performance (and Porsche are no real exception). Not helping me resist the no-more-mods principle, though! Russ

 

[PSH]

ORIGINAL: JagdHamster Awesome thread, Pete. Very informative and most interesting. I know from (many) previous turbo-charged models that standard intercoolers are very often the weakest link for enhanced performance (and Porsche are no real exception). Not helping me resist the no-more-mods principle, though! Russ

Hi Russ haha.. yes the 'no more mods syndrome' been there, got the t-shirt, etc etc... I started out like most with the trusty Boost Enhancer, that was about 15 years ago.. it's been down hill ever since... thanks for the kind words on my build... Pete

 

[PSH]

evening all... Another small update.... engine is now off it's stand, first time in nearly 3 years..lol the resurfaced flywheel has been refitted although not torqued up yet. Flywheel is a fraction under minimum at 25.2mm but it's close enough. After doing a little research on lightened flywheels fitted to 944T's i decided they weren't for me so had the original ground down to get it nice and flat again, it had a number of deep grooves after over a decade of abuse. The photo is a little off colour, the red is in fact very bright and shiny.

Next step will probably be re-installing the short block into the car... hopefully in the next few weeks. Pete

 

[Diver944]

Yay - progress at last []

 

[amrbose14]

Do you have any tips on how you fitted the new diaphragm and spring (for that matter, put it all back together)? Some pics would be nice. Chris

ORIGINAL: PSH morning guys.. not so much an update but an information post for others who may need to overhaul their own wastegates.. these are the service parts from Lindsey racing. Diaphragm: LR-WGD-101 @ $89.95 Wategate spring : LR-WGS-104 $ 15.00 total cost was £93 for the parts and £20 import/VAT duty Although the diaphragm currently on the wastegate hasn't failed it's very hard around the centre and will fail at some point in the future, so best to do this now while the car is in parts. I changed the spring for added security but on measuring the two springs they seem to be the same size although this isn't a test to see if the old spring has lost any strength, so again it's a 'do it while you can' scenario. I'm also considering machining a spacer to give the standard spring more resistance, same job as the Lindsey racing shims but an internal solution rather than their external one. I have now checked the valve seat and the standard exhaust valve seat for the head is of the same size, alas I don't have a 45 degree valve seat cutter so may farm this out although I'm looking into the cost of such a cutter first. Pete

 

[PSH]

Hi Chris I haven't got around to doing that yet, need to get the valve seat replaced first due to it being cracked in 4 places and thus would never seal. Plan is to do this probably next month when the head is taken in for new valve guides. As it happens the Porsche valve seats for the head are the same size as that in the wastegate and i have a set of four sitting in my workshop so I'll just drop it off with the new seat, doubt it will cost much, estimate £20-£30. I will certainly give full details here once it's done. Cheers Pete

 

[PSH]

I must be on a roll.. another update, in as many days.. I'm including this as IMHO it's an important and cheap job to do when changing your clutch, this being to replace the clutch release fork needle bearings. I bought mine from design911 but i'm sure they will be available from any Porsche specialist or OPC. First job was to remove the old worn bearings from the fork, simple job as they are only a drift fit. Clamp firmly in a vice but making sure you do not put any pressure on the fork's themselves, these are a known weak point in the design and don't need me being heavy handed to help them on their way... Picture shows a new bearing starting it's journey into the journal , with the old bearing sitting behind for comparison. I used a 21mm spark-plug socket as a drift fitted to a short extension bar, be sure to hammer the bearing in squarely on it's first hits. The bearings have lettering on one end, not sure if they have a right/wrong way around but followed the originals with the wording uppermost.

And to show the completed item, here's the clutch fork all cleaned up ready for refitting..

Pete

 

[944Turbo]

Also might be worth rotating the shaft that runs in the bearings it tends to get pitted on the side with the pressure.

 

[PSH]

Good point Tony...I had considered buying a new shaft but at nearly £40 when mine looks in good condition decided the money would be better spent elsewhere. I have taken note of your suggestion and will try to remember it when putting the parts back together, which shouldn't be too far away.. Cheers Pete

 

[944Turbo]

I think it might need a bit of light modifying to work the other way round, nothing for a man with your skills / workshop!

 

[PSH]

Thanks for the heads up Tony, will check it out.. Pete

 

[James Beaumont]

Just been reading the hole thing, looking forward to when its on the road report.