home register FAQ memberlist calendar

Go Back   Turbobricks Forums > Mechanical > performance & modifications

Reply
 
Thread Tools Display Modes
Old 08-30-2013, 12:09 PM   #26
cwdodson88
Board Member
 
Join Date: Oct 2011
Location: The Dalles, Oregon
Default

Maybe I had too many whilst going through the initial tuning... Now that I read through it again, 3 full turns out is around baseline. Yeah, they call that bump in the carb throat the "bridge"... So, my dyslexia got me again. THANKS GUYS
cwdodson88 is offline   Reply With Quote
Old 08-30-2013, 12:13 PM   #27
vvpete
Board Member
 
Join Date: Feb 2005
Location: Land of Enchantment
Default

3 turns isn't that rich, IIRC a usual tune for a R-Sport head and R needles was ~2 1/2 turns, and they are rich needles compared to DX. Your motor should be fine on DX. When you set them what was your idle?

I would also agree with John your float level is too low, which may be why the adjustment is as much as it is, the fuel level in the jet is too low. Also you would run dry/lean on fuel at WOT with a level that low.

Oh another note, when you get the single OEM Volvo HS6 heat shield, coat the thing with POR-15 alumnimum manifold paint and especially polish smooth and do the underside bright & shinny. I've made them from stainless steel sheet before, but the bright alum coating on the OEM Volvo hs works far better. Doing the hole pattern for 2 carbs is a PITA to get right.
And it would look more purdy.

Last edited by vvpete; 08-30-2013 at 07:04 PM..
vvpete is offline   Reply With Quote
Old 08-30-2013, 01:29 PM   #28
cwdodson88
Board Member
 
Join Date: Oct 2011
Location: The Dalles, Oregon
Default

I'm thinking plate aluminum for the shield, with a second plate under the bowls, it'll be 2 layers of 1/8" aluminum with 1/4" standoffs in between the 2 plates. Ordering spacers today and some extra gaskets.

I'll re adjust the floats tonight and get back.
cwdodson88 is offline   Reply With Quote
Old 09-02-2013, 01:14 PM   #29
ALR11606
Board Member
 
ALR11606's Avatar
 
Join Date: May 2012
Location: Louisville Ky
Default

To the Weber DGV comment it is true...These dgv carbs suck, I wish I had spent the money on a DCOE manifold and bolted my Weber 44s on. My gas mileage sucks with the dgv to the point that it makes my fathers dual 44 powered fiat look fuel efficient.
__________________
Sold 244 turbo
Current vehicles

1981 Fiat X1/9 "the jackstand statue"

2016 Focus ST "the daily with pep"
1984 Nissan 200sx s12 Turbo "the slidey beater"

Doesn't own a Volvo anymore still comes to TBricks for the fun of it
ALR11606 is offline   Reply With Quote
Old 09-02-2013, 04:08 PM   #30
$EEKING 945 TURBO WAGON
Board Member
 
Join Date: Jan 2012
Location: 47933 Shipping ZIP; Midwest
Default Noob

I know nothing about these, do they have the rubber sleeved, slip happy crank pulley? If so, the timing marks might be giving a false reading.
$EEKING 945 TURBO WAGON is offline   Reply With Quote
Old 09-02-2013, 05:44 PM   #31
PRVersion
regretting name change
 
PRVersion's Avatar
 
Join Date: Feb 2005
Location: Portland
Default

Pretty sure it just has an all-steel pully.
__________________
Quote:
Originally Posted by XxJenoxX View Post
PRVersion wins.
Quote:
Originally Posted by golgothan View Post
accelerate til the last possible moment, then accelerate more...
PRVersion is offline   Reply With Quote
Old 09-02-2013, 06:36 PM   #32
cwdodson88
Board Member
 
Join Date: Oct 2011
Location: The Dalles, Oregon
Default

Stamped steel with a key way, checked out the floats and they look good. Now they're up to about 1/8-1/4" from the top of the bowls after a WOT Shutdown. Nothing coming out of the weep holes, but I'm still boiling fuel. I'm waiting on some phenolic spacers and then I'll put a two layer aluminum heat shield on. Hopefully that will fix the issue.
cwdodson88 is offline   Reply With Quote
Old 09-02-2013, 06:46 PM   #33
Redwood Chair
K-jet For Life
 
Redwood Chair's Avatar
 
Join Date: Mar 2007
Location: - Stock PSI Or Bust -
Default

Quote:
Originally Posted by $EEKING 945 TURBO WAGON View Post
I know nothing about these, do they have the rubber sleeved, slip happy crank pulley? If so, the timing marks might be giving a false reading.
Quote:
Originally Posted by PRVersion View Post
Pretty sure it just has an all-steel pully.


 photo 140B20CrankPulley2.jpg

 photo 140B20CrankPulley1.jpg
__________________
Raise The Lowered


Image hosted by servimg.com

Quote:
Originally Posted by hiperfauto View Post
Folks on here don't know a good deal when they see it.
how psi stock cna support?

Redwood Chair is offline   Reply With Quote
Old 09-02-2013, 06:48 PM   #34
JohnMc
PV Abuser
 
JohnMc's Avatar
 
Join Date: May 2004
Location: St. Louis
Default

Quote:
Originally Posted by cwdodson88 View Post
checked out the floats and they look good. Now they're up to about 1/8-1/4" from the top of the bowls after a WOT Shutdown.
That's not how you set the float levels, or check them. But sounds like you've got bigger fish to fry (lol, heat pun) anyhow.
__________________
'63 PV Rat Rod
'93 245 16VT Classic #1141
JohnMc is online now   Reply With Quote
Old 09-03-2013, 10:59 AM   #35
cwdodson88
Board Member
 
Join Date: Oct 2011
Location: The Dalles, Oregon
Default

Yeah, So I had set the floats the first time just by what the book says... float bowls empty, pulled the tops flipped them over and set them to about 3-5mm from the tops... they squirted all over when I'd do the WOT shut down. So I re-adjusted and the bowls were about 1/2" from the top with gas on a WOT shut down. Now after the 3rd time of fiddling with them they are holding steady at 1/8th from the top of the bowls, but I still get some weeping about 30-60 seconds... The last time I watched the float bowls after I shut it down and pulled the tops off and it was boiling pretty well, 3-5 bubbles every 5 seconds or so... So that has to get solved before I can drive it again... Phenolic spacers should do the trick along with a heat shield, right?
cwdodson88 is offline   Reply With Quote
Old 09-03-2013, 11:07 AM   #36
JohnMc
PV Abuser
 
JohnMc's Avatar
 
Join Date: May 2004
Location: St. Louis
Default

I think the heat shield is 99% of the issue here. Heat via the intake manifolds would have to travel a very convoluted path to get to the separate float bowl of an HS6 carb.

Last edited by JohnMc; 09-03-2013 at 11:59 AM..
JohnMc is online now   Reply With Quote
Old 09-03-2013, 11:56 AM   #37
smokeyfan1000
Guest
 
Default

Have you replaced the float valve and seats? Checked floats for holes? 20+ year old ones do not work so well.
  Reply With Quote
Old 09-03-2013, 02:42 PM   #38
cwdodson88
Board Member
 
Join Date: Oct 2011
Location: The Dalles, Oregon
Default

John, how should I be setting the floats? At WOT I'm using the most fuel, shouldn't I be making sure I'm full after using a bunch more fuel? It doesn't squirt any excess at idle, and there is plenty of fuel at idle, so I think my fuel consumption concerns should be after a hard accel run to ensure that I still have adequate fuel with return to idle, no?
cwdodson88 is offline   Reply With Quote
Old 09-03-2013, 02:43 PM   #39
cwdodson88
Board Member
 
Join Date: Oct 2011
Location: The Dalles, Oregon
Default

Floats are new and no leaks or filling with fuel...
cwdodson88 is offline   Reply With Quote
Old 09-03-2013, 02:46 PM   #40
JohnMc
PV Abuser
 
JohnMc's Avatar
 
Join Date: May 2004
Location: St. Louis
Default

As far as I know, the way to set them it to remove the lid, flip the lid over so the float pushes the valve shut (i.e. don't push on it, even if you have those goofy spring loaded valves), then measure the distance between the lid and the float.

If everything is working properly, there shouldn't be any difference in float bowl level between idle and WOT, the whole purpose of the float valve system is to maintain a constant float bowl fuel level.
JohnMc is online now   Reply With Quote
Old 09-03-2013, 07:16 PM   #41
vvpete
Board Member
 
Join Date: Feb 2005
Location: Land of Enchantment
Default

Quote:
Originally Posted by JohnMc View Post
As far as I know, the way to set them it to remove the lid, flip the lid over so the float pushes the valve shut (i.e. don't push on it, even if you have those goofy spring loaded valves), then measure the distance between the lid and the float.

If everything is working properly, there shouldn't be any difference in float bowl level between idle and WOT, the whole purpose of the float valve system is to maintain a constant float bowl fuel level.
+1 to this. IIRC the correct spec is 3/32 to 1/8". I use a drill bit of that size, (keep it on the smaller size for full level) place it across the float bowl lid while upside down and lower the float until it's just supported by the drill bit.

The thing to keep in mind, esp for performance, getting the fuel level exactly but not above the jet top surface at the carb throat is what you want. The +/- on the level setting is to make sure the level is BELOW the top of the jet when the jet is properly adjusted. If it is not, and fuel level is above that, you get umetered fuel pushing past the needle, spewing into the intake when you want it to idle, and your adjustments go out the window.

If you really want to get it right, take the piston off and look down into the jet, fuel level should be right below the top of the jet.
vvpete is offline   Reply With Quote
Old 09-04-2013, 01:46 PM   #42
cwdodson88
Board Member
 
Join Date: Oct 2011
Location: The Dalles, Oregon
Default

ok, theres some info that I had not heard before...
Quote:
Quote:
Originally Posted by JohnMc View Post
As far as I know, the way to set them it to remove the lid, flip the lid over so the float pushes the valve shut (i.e. don't push on it, even if you have those goofy spring loaded valves), then measure the distance between the lid and the float.

If everything is working properly, there shouldn't be any difference in float bowl level between idle and WOT, the whole purpose of the float valve system is to maintain a constant float bowl fuel level.
+1 to this. IIRC the correct spec is 3/32 to 1/8". I use a drill bit of that size, (keep it on the smaller size for full level) place it across the float bowl lid while upside down and lower the float until it's just supported by the drill bit.

The thing to keep in mind, esp for performance, getting the fuel level exactly but not above the jet top surface at the carb throat is what you want. The +/- on the level setting is to make sure the level is BELOW the top of the jet when the jet is properly adjusted. If it is not, and fuel level is above that, you get umetered fuel pushing past the needle, spewing into the intake when you want it to idle, and your adjustments go out the window.

If you really want to get it right, take the piston off and look down into the jet, fuel level should be right below the top of the jet.
After watching it run and shut down, that makes perfect sense as to why it seem'd to be fine while running on the way lean side of things. Looks like my SU knowledge is still in the early stages. I was just looking at the floats, and not the relation between the jet level and the bowl levels... I'll recheck tonight.

Thanks!
cwdodson88 is offline   Reply With Quote
Old 09-05-2013, 10:51 AM   #43
cwdodson88
Board Member
 
Join Date: Oct 2011
Location: The Dalles, Oregon
Default

I readjusted the float levels to just under the hole in the jet and all is a lot better.

Installed a heat shield and fuel is no longer boiling in the carbs. I still seem to have some issue though. It doesn't idle at anything less than 1k without a very awkward stumble. blip the throttle and its fine, let it idle for a few minutes and its back... I'm going to replace my plugs, rotor, and cap tonight in the hopes that solves it (the old ones are about 1.5 years old). I think I may have "un-sync'd" my carbs though... At 1k the lift pin tuning method for lean/rich changes the idle by about 100-250 RPM but I cant get it to go down to 600-700 without stumbling.
cwdodson88 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 06:21 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.