Saabscene Saab Forum - Saab Technical Information Resource banner

1 - 12 of 12 Posts

·
Registered
Joined
·
1,597 Posts
Discussion Starter #1
Out of interest, does anyone have any information on the reasction time of say, a B234R engine re. turbo spool up.
Say I floor the throttle at 2000rpm, how long does it take the for the boost to build to the spec. level?
This time will vary lots depending on engine and on the rpm selected but someone must have done some anaylsis at some point?
 

·
Registered
Joined
·
836 Posts
I think you must have engaged 'warp-drive'
All I can see when I play the video is a spray of waving coloured dots for a few seconds??
 

·
Registered
Joined
·
288 Posts
Originally posted by SJ:
[qb]I think you must have engaged 'warp-drive'
All I can see when I play the video is a spray of waving coloured dots for a few seconds??    [/qb][/b]
Download the latest mplayer from microsoft, or the divx codecs.
 

·
Registered
Joined
·
836 Posts
Vigge, for some reason it's working this morning

That seems pretty quick to come up to boost, I'll have to watch mine next time, but I guess it isn't quite as quick as that.
 

·
Registered
Joined
·
1,597 Posts
Discussion Starter #7
Vigge - what upgrades do you have (engine wise)? - as I agree that the boost picks up very quickly. Is this mainly due to a free flow exhaust?
 

·
Registered
Joined
·
1,448 Posts
IIRC Vigge was running a stage III setup?

A stock Viggen also builds boost very quickly. Full boost can be available as low as 2,200 rpm. Vigge was at about 2,400 in that vid I think. The freeflow exhaust helps a great deal at low rev spoolup.

The Viggen's cams, despite being bad powerwise, are good for spoolup, as is the tighter 05cm exhaust housing on the TD04 turbo. Both of which combined make some very high EGT's for a stock engine, but that's why it uses Nimonic valves.

Dubbya~
 

·
Registered
Joined
·
288 Posts
Adrian, that is correct the car is stage III modified in that video.

Here is a link to an old video of mine.
Viggen with SP stage I

Stage I video

Dont see much difference to the spool up time between stage I and III.

Some day soon I will make a new video. Spool up is alot faaster with the better flowing IC
 

·
Registered
Joined
·
1,448 Posts
Originally posted by Vigge:
[qb]Spool up is alot faaster with the better flowing IC    [/qb][/b]
*coughs* I think that I remember having a BIG debate about this a few months back. Huge thing about whether a big intercooler caused lag, or reduced lag.

I feel the need to pipe in and say I TOLD YA SO! Obviously it may not be true in all cases. But the Viggen's stock unit is tiny, and I had a feeling a better flowing one would reduce boost lag. It appears I might have actually been right about something for once! Dang, time to get out the champagne!

Dubbya~
 

·
Registered
Joined
·
288 Posts
Originally posted by Adrian W:
[qb]I feel the need to pipe in and say I TOLD YA SO!              Obviously it may not be true in all cases.  But the Viggen's stock unit is tiny, and I had a feeling a better flowing one would reduce boost lag.  It appears I might have actually been right about something for once!  Dang, time to get out the champagne!      

Dubbya~ [/qb][/b]
If you think of it this way:
Custom IC (like mine) has about twice the volume compared to stock IC, but it will flow 4 times better with same pressure drop. Logically thinking the better flow will compensate for the extra volume.
 

·
Registered
Joined
·
1,448 Posts
Right Vigge! But that's exactly what I said and no one believed me! *sniffle*

The volume of air in the intercooler isn't even equal to the volume of air your engine takes in on one or two rotations. I never understood why people thought a large one would cause lag. *shrugs*

Dubbya~
 
1 - 12 of 12 Posts
Top