How long will a T7 produce maximum torque? [Archive] - SaabCentral Forums

: How long will a T7 produce maximum torque?


IanT54
4th December 2008, 06:07 PM
I'm asking this because I noticed something last night that I've kind of been aware of for a while:

If I accelerate WOT in 2nd gear from about 2500 rpm the car pulls like crazy with a huge increase in torque from about 3500 up to about 5500 - it feels really 'cammy'.

If I accelerate WOT in 1st from a standstill I get the same effect but when I change into 2nd (still WOT) I don't get the same acceleration - no 'cammy' feel at 3500. It's almost as if the engine says 'that's enough excitement for now'.

I don't think this is any limp mode thing because if I slow down and then do a WOT 2nd gear run again I get the same 'cammy' feel going through 3500 rpm.

Does anyone know why this is happening? I'm pretty sure I'm not imagining it.

The car is stock btw, except for a GS open air intake (which seems to have made a significant difference).

Cm452
4th December 2008, 06:14 PM
My T5 feels very "cammy", even with little boost but higher revs, I can feel the engine come "on cam" @ 28-3400rpm.
-Cm

comtrang
4th December 2008, 06:15 PM
Sounds like heatsoak to me. You have the stock, dual pass intercooler correct? After going heavy on it for a little while, it feels 'tired'? Yeah, sounds heatsoaked. Nice intercooler upgrade will take care of that.

EDIT: Looks like you have the Viggen intercooler, but still not too far off from the dual pass, for heatsoak.

IanT54
4th December 2008, 06:18 PM
Thanks comtrang. So I'd get heatsoak just accelerating WOT through 1st gear?

SaabHat93
4th December 2008, 11:39 PM
I've noticed this as well, but after 2-4 WOT pulls. 1st definitely feels tired. On cold(er) days it pulls harder and longer and boost holds a lot longer than on hot(ter) days. New and better intercooler would do wonders..

comtrang
5th December 2008, 12:21 AM
Thanks comtrang. So I'd get heatsoak just accelerating WOT through 1st gear?

I've noticed this as well, but after 2-4 WOT pulls. 1st definitely feels tired. On cold(er) days it pulls harder and longer and boost holds a lot longer than on hot(ter) days. New and better intercooler would do wonders..


Yep, and if you did have the dual pass intercooler off of a NG900 or non-HOT 9-3, it'd be even less than a gear. Cold days are nicer obviously because it'll take longer for the intercooler to get hot and warm your air. I did a dyno before and after my huge ebay intercooler - going for about $100 now all over ebay - and I also gained about 10whp throughout a lot of the RPM band. Most of all I was just happy that my car didn't need a breather every WOT gear pull. Now I can go gear after gear and if there's the slightest heatsoak, I don't notice it. An upgraded intercooler is definitely necessary if you plan on upping your power and driving your car the way it should be driven :D

SaabHat93
5th December 2008, 01:20 AM
An upgraded intercooler is definitely necessary if you plan on upping your power and driving your car the way it should be driven :D

Agreed..

Did you get one of the CxRacing ones? If so did you have to mod the bumper at all? I know lot of the ebay ones aren't bolt-on, which I'm not up for :confused:

comtrang
5th December 2008, 01:30 AM
Agreed..

Did you get one of the CxRacing ones? If so did you have to mod the bumper at all? I know lot of the ebay ones aren't bolt-on, which I'm not up for :confused:

Haha yeah, definitely not bolt on. It is a CXRacing one, 28x8x3.5 with 22" long core. We buzzed off a piece of metal on the bumper to make it fit but I wouldn't say anything major.

SaabHat93
5th December 2008, 01:37 AM
Yeah, I dunno how savvy I would be with cutting stuff off the car. Haha. Would be a fun project if I had some extra money lying around though :p

comtrang
5th December 2008, 01:47 AM
Oh it really wasn't bad at all, took all of 10 seconds. This was all done in a shop though, so air compressors and tools are available to make things a little faster :cheesy:

SaabHat93
5th December 2008, 02:12 AM
Yeah.. Shop time definitely requires the funds that I am not capable of earning right now. Good times, though.

comtrang
5th December 2008, 02:50 AM
I understand lack of funds man, I'm sure we've all been there. Fortunately my dad's a mechanic so it's his shop everything takes place in.

SaabHat93
5th December 2008, 04:00 AM
Deng.. I wish I at least had a friend that was a mechanic. Would be awesome. Glad to see you're using your situation to it's fullest potential. :cool:

saabkid37
5th December 2008, 12:34 PM
the engine "comes on" because i believe boost is limited in 1st in 2nd gear, although that might be t7 only.

IanT54
7th December 2008, 10:24 AM
Sorry to bump this thread but I've got another question. First though, the temperatures here have gotten colder (< 0c) and I've noticed that I can now boost through 1st and part way through 2nd which absolutely confirms what you said comtrang. Heatsoak is definitely the issue.

Now for my question: most of the replacement ecu packages I've seen don't come with (or even recommend) an improved intercooler e.g. the BSR ecu's just recommend 3" downpipe and open air filter to stage 3. If an improved intercooler is so important (and I'm convinced now that it is!), even for a car in base level of tune (such as mine), wouldn't these ecu tunes suffer big time from heatsoak?

John Z Williams
7th December 2008, 12:27 PM
I have done a lot of these tunes and testing and a larger more efficient ic is one of the first things that should be done before upping the power.

What good is a tuned ecu with more power if you only have it for one gear or even half a gear?

Making power 101, get the air in, get the air out and cool it down.

This means: intake, exhaust, IC

This is the "proper" way to get the power out of you're car and once you have those hw items, you can take full advantge of sw or a tuned ecu.

John

IanT54
7th December 2008, 01:58 PM
Makes sense. Thanks John.

Do you ever do tuning sessions outside of Boulder? I'd be interested at some point, but you're a long way from Toronto!

comtrang
8th December 2008, 12:11 AM
I think those who have done this type of thing in the past required a lot of interest before doing so..otherwise it wouldn't be worth it, obviously.
Not sure what John would say to this, though, as he's a fairly new tuner and I don't think he does this for a living so..
I'm sure he could send you a tune that would work just fine, you don't have to worry so much about really fine tuning things until your cars at the point of making the earth tremble :x.

Well, anyway, we'll see what he says.

John Z Williams
8th December 2008, 12:39 AM
Makes sense. Thanks John.

Do you ever do tuning sessions outside of Boulder? I'd be interested at some point, but you're a long way from Toronto!

I have been playing with this now, it is a great tool for people to see live tech 2 data on their sid screen, clear it out and all reads normal, press it again and you can read all the good info, airmass request, torque request iat, coolant temp, tps and everything else that is nice to see.

Here is a video of how it works and looks,

http://www.youtube.com/watch?v=ZcsC38mIrVY

John