It's funny you say that, i'm not actually a patient man, quite the opposite! I think the amount of time, the number of sleepless nights, the big highs followed by the lowest lows with this car over the last half decade have forced me into a mental state of expecting disappointment, i simply don't get upset about it anymore, sad isn't it! What i'm doing with this car, and what many others on here have and are doing to theirs, most likely isn't what they actually planned originally, it just turned into something else.
If i had the £80k or $160k that this car has taken from me since i took the keys in my hand this minute then i wouldn't be driving/building this 9930 frankenstein monster, i'd probably be in something else.
The fact is i've fallen in love with the car, partly because it owes me more money that it's ever going to be worth, and partly because it's a member of the family.
It's certainly snowballed, but these things do don't they, you only live once

 

Hope you get it sorted Jonathan, and if it it's any consolation my 3.2 carrera is playing up

 

Jon
I can appreciate much of what you say about disappointment, high highs, low lows, not getting rid of it because it owes me far too much money.. I try to block out how much mine has cost me - reading your figure did make me feel a bit better ("I am not alone!")

What sort of BHP are you hoping for on Saturday?

Speaking to a tune-specialist in Lincolnshire recently, and he told me that he's convinced the 993tt engine was originally designed to be twin-plugged. He said that the way everything fitted together was "too perfect" - it's just that, at the time, Porsche was in financial difficulty and a difficult-to-drive, 500+bhp monster with horrendous servicing costs would have been irresponsible.

Nathan
What's up with the "little runabout" (3.2)?

 

The 3.2 drives but "feels" as though it's either running too rich or the ignition is way too advanced.
No smoke, down on power, no razor sharp throttle response, a noise like it's running rich & feels out of balance due to the poor running.
I've checked the CHT and the IAT sensors with my meter & they are within spec. Next step is too pull out the plugs and look for clues, maybe one is shot or has simply worked loose. Will also check the cap and rotor.

 

Yeah, mate, I know exactly what you mean - have the same kind of problem with my "old, red bus"!!

I'm booked in tomorrow morning at AET Turbos in Wakefield for a Dyno Pull and AFR tuning. They have some system without Rollers - have to take the wheels off - eliminates tyre slip from the equation... So I hope to know a bit more by tomorrow afternoon.

I notice a bit of rocking from side to side in my car when at tickover in traffic - last time it did that, it was only firing on 5 cylinders; car otherwise drives okay, but doesn't feel quick. (Just feels like 40 or 50bhp has gone missing somewhere.)

I recently replaced the dizzy cap (previous one didn't fit tightly an could spin). Current set of plugs can't have done more than 7,000 miles. Timing is bang on at 27deg BTDC and, although the car is capable of 160+mph, doesn't feel all that sharp... I'm a bit stumped..

 

TJ, i'm not sure what HP to expect, definitely north of 450 i hope. Andy said he didn't want to go real aggressive with the tuning yet as there are a few things that need to be addressed, it has headroom for more which is good, like i said earlier though i just want it to run right and be reliable, once i've got a few thousand miles on there i can look at it again.

Something to check with your car, mine was acting similar to yours once and it turned out the arm inside the distributer that advances/retards the ignition had rusted through and broken, might be worth a look? If your ignition is correct, your fuel delivery and AFR's are good and you're getting full boost i can't imagine what else could cause a loss of power? Weak spark? Clogged airfilter? Dodgy fuel pump or pumps? The results on the dyno should be telling, be sure to let us know how you get on, I guess you won't be coming to the dyno day on Saturday?

 

I had dodgy oxygen sensors, one complete failure and two with intermittent problems, will replace all four.
Please no more problems

Should get it back tomorrow

 

Thought i'd better post the dyno results, the ECU is pulling boost at around 5000rpm, it could be a bit lean and it's sensing knock, nothing seamed hot so i doubt it was temperature. It is going back on Monday to get tweaked so i guess these numbers will change but here they are anyway. BTW, i don't believe the torque figure.

 

What's the boost target?

 

I'm not sure what the peak target was (1.2bar - 1.3bar?) and to get down to 1.0bar quite quickly, which reading the andial boost gauge in the car it does.
It isn't as happy on the dyno as it is on the road, the dyno pull was in 3rd gear and the ECU was pulling out at around 5000rpm, it never pulls anything (noticeable) on the road in 3rd, but on WOT in 4th it pulls boost down to around 0.5bar once you get over say 4500rpm. It's funny because sometimes it pulls boost and others it doesn't, it never pulls anything when in 3rd on the road.

I think it's mapped too lean, i did some hard runs in it to get some data on the AX22, repetitive hard runs, i stopped and quickly popped the engine lid to get a feel for how hot the engine was getting, the end tanks of the intercooler were hot and the cores and centre section were cold, not medium hot or warm, they were actually Cold.

I watched James' car on the dyno, very impressive but he couldn't get traction, i think he settled for 550bhp at 1.0bar, it wouldn't hold on at 1.2bar. The reason i mentioned James is that his afr's were unbelievable, basically draw a line with a ruler across 0.8 Lambda and you get the picture, i know it's probably safe to go a bit leaner but i want to see the same value on mine.

 

Jonathan,
Hi Mate! Are you using the stock ECU or a programmable one? If using the stock one you might want to get a chip burned to get a better map in it. If its programmable looks like a couple of hours on the dyno to get it tuned in. It could be your injector pulse width is too narrow. That shuts off the injector before the full charge is pumped in the chamber which would make it run lean. I know, a few more quid into her, but what the hey, you've gone this far, and you certainly don't want to grenade another motor. Good luck and keep us posted on how its doing.

 

JBL930,
As you said the hp/tq curve don't look right. As most of you should know hp/tq should be equal at around 5250 rpm. In this case hp/tq crosses at 4200 rpm? That don't look right. Any idea what rpm you ended the run? It looks like the graph is shifted 1000 rpm to the left which may explain strange hp/tq curves.

Take your time in getting your engine in tune.

 

Hi Jim
The mapping has been done by a company called Fearnsport, they are based in Silverstone. I've taken the car back up there today for them to sort out, they do all their mapping on the road so it should be spot on, hopefully it'll be right this time.
I was under the impression that it had a 5.0bar fuel pressure regulator on there, it turns out it doesn't so that should cure the fuel issue.
While it's there they are fitting better BOV's,

these are apparently as good as you can buy, just thought i may as well because the ones on there are different makes and may be reacting differently.
They are going to be a little more conservative with the boost level too so i assume the power figure will drop some. I'll be happy with 500bhp as long as it's nice and safe, it's all about torque anyway and this thing has that in spades.
The rear suspension almost bottoms out under hard acceleration, it's savage!
I've just sent Jean a file from an AX22 run i did yesterday, i got 60-130mph in 7.75 seconds with two people and a full tank of petrol, that's CGT beating speed

Hi Mike, i think because the torque figure was so high he changed the scale of the graph, the run stopped at 5000rpm because the ECU just pulled the boost down to 0.5bar, plus it was looking too lean so we just left it there.
I'm certain that the torque figure is bogus, 630ftlb's is around 855nm, it simply cannot have that much torque. Besides, you need to do a damned site more work to a 993tt engine than i've done to mine to be seeing those figures.
Jean is going to look at the run i did and he will be able to quite accurately tell me what HP and torque i've got, it'll be interesting to see how much it differs from the chassis dyno numbers

 

Sounds like progress is being made! Good luck with her Jonathan.

Cheers,
Jim

 

Well spotted, it doesn't look right because the stupid graph doesn't have bhp and tq at the same level, take another look.