I'd like to get other people's opinions on the obvious turbo lag of the HPT.

It actually probably has me driving safer at slow speeds. I try to avoid the turbo kick without realizing it, especially when I'm starting from a stop at a light. Hopefully I'm not as bad as the people who typically annoy me because it takes them so long to get moving you think they nod off any time the car stops.

The big problem is on-ramps. If I've got to stop then floor it to merge I've got almost a good second before I move!

My 780 probably hadn't see a mechanic in a good while when I picked it up. But I drove it 1000 miles home (yes crazy) and it seemed to perform better. Minimal lag and better at the 80-90 MPH passing. But its been years since then and its not running now so I can't really compare.

And isn't the C70 "850-based"? My dad had a 96 855T and I remember the feeling of "oh this isn't much" when you put your foot down followed by "holy sh*t I'll never be able to stop this!". But it seemed to come on quicker and more smoothly. The C70 really is, as someone else here put it, a kick in the ****.

I did have my check engine light on for quite awhile with no apparent problems but it went off last week and I see no difference in performance or gas mileage so I don't know what it was. Its going in for the 60K service (about 5K early) so I'm hoping there's something *minor* wrong that will make it a bit better.

Yup, the HPT does have a bit of lag. I have been doing reseach and am planning my mods carefully to address this issue. Anyone can correct me if I'm wrong but this is what I understand needs to be done to reduce lag on a stock HPT car:
The best way to make sure your getting the best boost is to make sure you're running only premium gas. (you'd be surprised how many don't)
The second thing is to get the engine to breathe better at both ends. A high flow air filter can be a good start or a fresh air upgrade by IPD, EST or "other" (seen some nice custom jobs)
The next best thing is to add a chip upgrade, RICO, TME (IPD's) Speedtuning all have something that will work.
Finally, open up the exhaust: down pipe and cat back. There are emission friendly kits from the companies mentioned above but I have heard good things on having a shop do it custom and it doesn't cost a bunch more.

For my C70, I have the K&N Filter and will do the exhaust next. Then I will get the chip flash most compatible with the way the engine breathes. I understand then the turbo lag is substantially reduced and the acceleration kick is way better. :amen:

CP

before you go for the chip, try upgrading the plugs and wires. i've seen some really crappy wires almost kill performance on an engine. for 89-780T, you mentioned the check engine light, have you scanned for codes? if so, what are they? you also mentioned that you drove 1000 miles and didn't know when the last servicing was, um, time to service. do a complete oil change and flush, refill with a synthetic then see if there is a difference with trubo lag. lag will always be there, HPT or not. it's how you deal with it. service it first. keep us posted.

No, no when I bought my *780* I drove it 1000 miles home. The point being it was old, running well but probably not perfectly and still felt better than the C70.

Premium gas, of course even though its extra painful now.

The car is under warranty so I can't make any major, obvious mods. But drop-in K&N filer and better plug wires shouldn't be a problem.

It should be going into the shop soon and I'll post an update afterwards. Does anyone know where to find the list of what is checked at the factory service intervals? I remember seeing a chart when I downloaded the owner's manual but now I can't find that section on Volvo's site.

you can make mods to your car, obvious or not. the dealership can't say squat, unless it can be proven that your mods are a detriment to the cars longevity. that is legalese for proving that you street race your car. any and all mods, legal with certification stating that it is for ON-ROAD USE is perfectly legal and CAN NOT BE DEEMED OUT OF WARRANTY. there was a huge court case about it and the driver won against the dealership, honda i think. so unless you get one of those off road parts(meaning dragstrip), they can't say anything. but start slow and build up, better to build your base, levels1, 2, etc. then going for a level 100 and blowing your engine. dig?