940 lpt turbo advice

[tonka12]

It's a 97 lpt m90 car, already have boost gauge and mbc, set at 10 psi,it goes ok but runs out of puff at about 4500 to 5000.
And yes I'm handy with spacers,it's my daily driver, and the fuel consumption isn't an issue, I've got a td04 12t off a c70 t5, but it doesn't look much more than th 13.and I'm thinking of chipping it but want to sort the turbo first, thanks for the advice chaps

[360beast]

12T? That will be a pointless upgrade if it is one at all. From what you have said it isn't the turbo holding you back but the camshaft. The standard cam dies at 4500, you will want an A or V cam.

[Laird Scooby]

Even with a hotter cam, you're still not going to make it a screamer, it's a red block and they just don't scream, they slog. Yes, they can be made to rev but that's not the point i'm trying to make,
A hotter cam will shift the power band up and let the engine breathe better at higher revs and some more power out at the top end but you will likely lose something at the bottom end.

When you say "real world performance", what exactly do you mean? Do you mean being able to leave the traffic lights faster than a Ferrari or do you mean better overtaking power?
Or, do you mean you want big dyno figures and aren't worried about being able to drive smoothly at town speeds?

I'm a bit confused about what you're trying to achieve and with no disrespect, i'm not sure you know what you're after - can you please clarify?

[TonyS9]

What exactly do you mean by "running out of puff"? Is the turbo pressure dropping?

I run standard 13C turbo at 12 or sometimes 14psi on the track in my 97 B230FT in a 360. Its a bit lean at 14psi according to the narrow band O2, but goes ok. I didn't notice any difference between T and A cam. The Engine revs nicely to 5.5 or 6K.
The only mod other than a bleed valve I run is wasted spark.

[tonka12]

Not after a traffic lights screamer, just safer over taking, the turbo doesn't drop off boost,holds steady, and I'm not after big power just to make it a better driving car,

[Laird Scooby]

Originally Posted by tonka12

Not after a traffic lights screamer, just safer over taking, the turbo doesn't drop off boost,holds steady, and I'm not after big power just to make it a better driving car,

Are you saying you're losing boost pressure at the moment? Weak or maladjusted wastegate actuator will cause this as wil any blockages or worse still, holes in the exhaust pipe.

Assuming your exhaust is ok, the logical fix here is an HPT wastegate actuator, fixes the boost drop problem and increases your power/performance/mid-range.

[tonka12]

No boost drop holds it fine, just thinking it needs more, the initial urge is great but just seems to lose its urge,

[TonyS9]

Yes, the LPT actuator isn't known to be stable at 10psi, its probably over boosting initially.