home register FAQ memberlist calendar

Go Back   Turbobricks Forums > Mechanical > performance & modifications

Reply
 
Thread Tools Display Modes
Old 09-15-2021, 01:33 PM   #26
klr142
Turbo, what?
 
klr142's Avatar
 
Join Date: May 2004
Location: OR
Default

Updated the first post slightly and added the different "steps/stages" from a later post to it.
klr142 is offline   Reply With Quote
Old 07-23-2022, 04:56 PM   #27
klr142
Turbo, what?
 
klr142's Avatar
 
Join Date: May 2004
Location: OR
Default

We had the General Leif on the dyno yesterday with its current configuration: Latest update in the build thread

SETUP:
This is with a wearing lobes, custom reground K cam (12.5mm lift, 259 degrees at .050” lift and 108LSA), 12.4:1 compression, B230E 96.6mm pistons, 43cc chamber 531 head (2.7mm off or so), stock size valves, opened chambers and some (mild?) port work by Robert, pistons set to .010” above deck, .045” Cometic MLS gasket, stock exhaust manifold with very mild port work, 1 7/8” custom downpipe with 450mm long runners before the 2-1 merge into a 2.5” pipe exhaust, stock ignition system with NGK BPR7ES plugs, Lh2.4 custom tuned, red body 1998 GLT injectors (same flow as 850T orange tops but 4 holes), B21F intake manifold with injector bungs added, a 90 degree elbow to a 960 throttle body with an 850na throttle plate and 960 MAF sensor.

We did not touch the ignition tuning this time and are still running around 29 or so degrees max advance like we were with the old setup in 2019 which was an Enem K13 camshaft (12.5mm, 106 LSA and I think 280 advertised duration which must be at some random lift), a 405 head prepped similarly to this 531 but with likely around 11:1 compression or possibly less. We're running 92 octane pump gas with nothing added to it. I have more fine tuning of the air/fuel ratio to do, and we could maybe try advancing the cam gear a full tooth because the final pulls were with the cam gear at it's 5 degrees advanced maximum. The other pull shown for the current setup is with the cam at 3 degrees advanced. You can see it has a little more pull up top, but we would prefer that good torque a little more as we're doing endurance racing! With some ignition and other fine tuning, we might be able to get back to the peak torque we had with the K13 as shown in the comparison chart. Some of the difference between the two new pulls are from it being leaned out in the lower-mid-range areas.

Anyway, not too shabby! We have an AGAP R33-264-14 with 105 LSA going in later this week that didn’t make it in time to be installed before the dyno day. Bummer! We’ll have to make another visit to the dyno some day. Hopefully we don't lose too much more of that lower end torque. If we do, we'll just have to get some ITBs and put on a more modern engine management. Maybe. That might be too much power for what we're looking for at the moment. HAH!
Attached Images
File Type: png 80803252-307C-43BD-9B7E-D995FB524141.png (55.6 KB, 104 views)

Last edited by klr142; 07-25-2022 at 12:26 PM..
klr142 is offline   Reply With Quote
Old 07-23-2022, 05:23 PM   #28
740atl
Gear acquisition syndrome
 
740atl's Avatar
 
Join Date: Apr 2010
Location: USA
Default

Holy **** that’s awesome!
740atl is offline   Reply With Quote
Old 07-23-2022, 06:01 PM   #29
klr142
Turbo, what?
 
klr142's Avatar
 
Join Date: May 2004
Location: OR
Default

We were happy with it, for sure! Especially how the power hangs even without a fancy intake or exhaust manifold on it. We’re really curious what it’ll do with the AGAP R33-264-14 and 105 LSA camshaft in it now (that’s Race profile, 264 degrees at .050” and 14mm of lift). Maybe we’ll go back for a few pulls on the dyno to figure out where it wants the cam timing and dial in the AFR a little more.
klr142 is offline   Reply With Quote
Old 07-23-2022, 09:12 PM   #30
shoestring
Board Member
 
shoestring's Avatar
 
Join Date: Jun 2009
Location: Swampscott, 01907
Default

How are you compensating for that much lift on your valve guides? Are you cutting them down or using longer valves or...?
__________________
I AM THE MODAL AMERICAN. Planet money #936.
shoestring is offline   Reply With Quote
Old 07-23-2022, 10:38 PM   #31
klr142
Turbo, what?
 
klr142's Avatar
 
Join Date: May 2004
Location: OR
Default

Quote:
Originally Posted by shoestring View Post
How are you compensating for that much lift on your valve guides? Are you cutting them down or using longer valves or...?
Both! Well, the guides may be full length and just pushed down a little farther, I’m not 100% certain. The valves are 112mm long. Culberro will chime in with details!
klr142 is offline   Reply With Quote
Old 07-23-2022, 11:08 PM   #32
culberro
Ronald Culberbone III
 
culberro's Avatar
 
Join Date: Feb 2010
Location: Redmond, OR
Default

Quote:
Originally Posted by shoestring View Post
How are you compensating for that much lift on your valve guides? Are you cutting them down or using longer valves or...?
The valves are VW air cooled race valves, and they’re 112mm long.
The intake guides are installed at 13mm above the stock spring pad (instead of the stock 15.5mm), and that’s just because of the seals. The exhausts don’t need to be set deeper.
The Erland Cox aluminum retainers sit a bit closer to the guides, so that had to be taken into account.

Usually I’d shorten the guides a few mm so they don’t inhibit flow on the intake side. They are tapered as well.
__________________
Cult Person. Pissing in your Kool-Aid.

Head work: https://forums.turbobricks.com/showthread.php?t=349975

Temp Sender Adapters: https://forums.turbobricks.com/showthread.php?t=348169

Last edited by culberro; 07-24-2022 at 12:02 PM..
culberro is offline   Reply With Quote
Old 07-24-2022, 12:41 AM   #33
klr142
Turbo, what?
 
klr142's Avatar
 
Join Date: May 2004
Location: OR
Default

What ^he^ said! Having the smaller base circle camshafts help, too. With our last 14mm lift cam, it had a 33mm base circle. The new one from Agap supposedly has around a 33.5mm one.
klr142 is offline   Reply With Quote
Old 07-26-2022, 12:20 AM   #34
redblockpowered
mails files to people
 
redblockpowered's Avatar
 
Join Date: May 2015
Location: Swampscott, MA
Default

Quote:
Originally Posted by culberro View Post
The valves are VW air cooled race valves, and they’re 112mm long.
The intake guides are installed at 13mm above the stock spring pad (instead of the stock 15.5mm), and that’s just because of the seals. The exhausts don’t need to be set deeper.
The Erland Cox aluminum retainers sit a bit closer to the guides, so that had to be taken into account.

Usually I’d shorten the guides a few mm so they don’t inhibit flow on the intake side. They are tapered as well.
This is very good to know, interesting. That stock intake guide sure is massive.
__________________
1993 944 B230FT/M90 thread here: http://forums.turbobricks.com/showthread.php?t=345277
2x 1991 245 B230F/M47 (LeMons car, street car)
I sell chips for LH 2.4!
If you live in the Northeast US, I'll drive to you and tune your LH 2.4 car!
redblockpowered is offline   Reply With Quote
Old 07-26-2022, 12:53 AM   #35
culberro
Ronald Culberbone III
 
culberro's Avatar
 
Join Date: Feb 2010
Location: Redmond, OR
Default

I taper them down on most builds.
I might just have some custom shorter ones made for the intake side, and have the exhausts get a side parabolic or radius end.
culberro is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 12:27 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2022, vBulletin Solutions Inc.