Sync with NO VBOOST?????

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dlopes

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Aug 18, 2008
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Location
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I just bought my 97' VMAX, and the vboost was removed. I just rebuilt the carbs and now I am having trouble synchronizing the carbs. Is there any special way to sync the carbs with the vboost removed? If it is easier to sync with vboost, what are the minimum vboost components I need to install for easier synchronization? After I get a good sync, I'll just run the vboost wide open all the time.

:hmmm:
 
You can get the Weber synchrometer as seen here:
http://www.thesamba.com/vw/classifieds/detail.php?id=564436

Only thing is you have to jump back and forth. Having two would make it a bit easier. another option would be to somehow plug the vboost runner. Maybe stuff a small rag or fit a small round piece of rubber in each of the two runners. This would get you close.

The minimum you would need to sync with vboost is the valve assembly. If you're not planning on using vboost you would not need the servo motor or controller. You could just use the cable to somehow wire it open. Someone on this list actually used a bicycle quick shift on his left grip.
 
I would not risk sucking the rag in and bending your valves.

I would order the synchrometer. If you have mercury sticks you could visually set 1-2 and 3-4 then use the mercury to stet 3&4 to 1&2 temporarily till the synchrometer comes.

Have any friends into VW bugs? Most of them already have a weber synchrometer.
 
I was looking at the carbtune pro that uses metal rods. Would that be sufficient or do I have to get the weber syncs? Also, which two are the vboost intakes? 1,2,3,or4?
 
Since no vboost you need something to measure vacuum at the intake side of the carbs.
 
There is another method to bench synch the carbs if you have them off the bike. I have used this to get me REALLY close on a couple of occasions.

What I have done is, with carbs on the bench upside down, open up the butterflies using the idle thumbscrew. Find a small, I use a 1mm, drill bit. Put the drill bit in the left front carb between the butterfly along the carb body. Close down the idle thumbscrew until the butterfly lightly (very lightly) touches the drill bit. I then use the synch screws to replicate this on the other 3 carbs. Re-install carbs and set idle speed.

Unfortunately I cannot remember where I heard about this or I would provide a reference. Seems to work well enough until I get carb sticks on them, as a matter of fact the last time I synched the carbs I did this first and found no adjustment necessary.
 
I tired this approach and it sucked! I had my carbs so far out of whack.
This would work in a perfect world if each cylinder had the same exact amount of vacuum.

I WOULDNT perform this method.

Either get a VBoost manifold (I sold one on EBAY 3 months ago for 25.00)
Or get the Mercury Synch. (I have not used one of these so I cant say)

Or take it some where and have someone put some mercury gauges on it.

When I lived in Fla. I had Joe from BoxxenStopp (Daytona Beach) synch my carbs with a High Dollar Vacuum gauge setup.

Save your money they sell these gauges on the internet. If they dont cost 350.00 and up they are JUNK I tried 2 different guage setups one for 49.00 and the other cost 75.00 both are in the trash..


There is another method to bench synch the carbs if you have them off the bike. I have used this to get me REALLY close on a couple of occasions.

What I have done is, with carbs on the bench upside down, open up the butterflies using the idle thumbscrew. Find a small, I use a 1mm, drill bit. Put the drill bit in the left front carb between the butterfly along the carb body. Close down the idle thumbscrew until the butterfly lightly (very lightly) touches the drill bit. I then use the synch screws to replicate this on the other 3 carbs. Re-install carbs and set idle speed.

Unfortunately I cannot remember where I heard about this or I would provide a reference. Seems to work well enough until I get carb sticks on them, as a matter of fact the last time I synched the carbs I did this first and found no adjustment necessary.
 
I guess I should stand corrected by the burrito eating, flex wobbler rider, scooter pilot LOL :rofl_200:..... Just wanted to pass on what has worked for me. I imagine with a higher mileage/abused engine it may not work as well due to the differences in cylinder condition etc. causing different vacuum levels across them, but with a newer engine such as mine it seems to work fine.
 
I guess I should stand corrected by the burrito eating, flex wobbler rider, scooter pilot LOL :rofl_200:..... Just wanted to pass on what has worked for me. I imagine with a higher mileage/abused engine it may not work as well due to the differences in cylinder condition etc. causing different vacuum levels across them, but with a newer engine such as mine it seems to work fine.


It may be worn out and who knows how many miles are on it:ummm: It's a $500.00 engine 155lbs of compression that was thrown in the flexxing frame. But ya know with this wore out engine and more poor tuning abilites I am not seeing to many passes faster than a 6.93 here.
I heard you dont need a tire gauage, If you take a qaurter and drop it on the tire and it bounce 2.6653 of an inch your at 36 LBS.:clapping:
 
ROFLMAO!!!!!!!! Will have to try the quarter test.... oh wait that is a US quarter that weighs different than a Canadian one..... hmmm may require testing:biglaugh: Thanks for keeping it real sir.
 
I am not running your bike in the qaurter!! Even if you never dragraced before I would atleast think you could get that beast down the track under some 10.90's

I dont care if its a canadian qaurter or the now value US qaurter, but I will give you a dollar if I can ride your bike down the qaurter :clapping:
 
I am not running your bike in the qaurter!! Even if you never dragraced before I would atleast think you could get that beast down the track under some 10.90's

I dont care if its a canadian qaurter or the now value US qaurter, but I will give you a dollar if I can ride your bike down the qaurter :clapping:

Next year if they do the UFO drag day, you come up and I will hand you the key, free of charge. If it breaks then it breaks, will just have to deal with it then. Of course if it crashes.........
 
You set the shiftlite and I wont miss a gear! No worries on wrecking your VMAX. Nor bouncing it off the rev limiter in the burnout box. If anything should break its due to a weak link and eventually it will break leaving you stranded on the road.

As long as your brakes work I will come back with a time slip and a huge grin!! :eclipsee_gold_cup:


Man I am just sitting here day dreaming about all that torque and HP you have on your machine and what it would feel like on a sticky dragstrip! I bet that thing pulls just as hard on the big end as it does in the first 300 ft as it feels you are digging up asphalt!


Next year if they do the UFO drag day, you come up and I will hand you the key, free of charge. If it breaks then it breaks, will just have to deal with it then. Of course if it crashes.........
 
You set the shiftlite and I wont miss a gear! No worries on wrecking your VMAX. Nor bouncing it off the rev limiter in the burnout box. If anything should break its due to a weak link and eventually it will break leaving you stranded on the road.

As long as your brakes work I will come back with a time slip and a huge grin!! :eclipsee_gold_cup:


Man I am just sitting here day dreaming about all that torque and HP you have on your machine and what it would feel like on a sticky dragstrip! I bet that thing pulls just as hard on the big end as it does in the first 300 ft as it feels you are digging up asphalt!


Shiftlite will be set @ 8500 and the R1 brakes on the front will stop ya.:biglaugh:
 
Oh yeah, and it pulls all the way up...... HARD!!!!!!!!!!!!!!!!! Will have the 3" over swing arm and the front is lowered 2.5" so front end should stay down too.
 
There is another method to bench synch the carbs if you have them off the bike. I have used this to get me REALLY close on a couple of occasions.

What I have done is, with carbs on the bench upside down, open up the butterflies using the idle thumbscrew. Find a small, I use a 1mm, drill bit. Put the drill bit in the left front carb between the butterfly along the carb body. Close down the idle thumbscrew until the butterfly lightly (very lightly) touches the drill bit. I then use the synch screws to replicate this on the other 3 carbs. Re-install carbs and set idle speed.

Unfortunately I cannot remember where I heard about this or I would provide a reference. Seems to work well enough until I get carb sticks on them, as a matter of fact the last time I synched the carbs I did this first and found no adjustment necessary.

Guys on the XS11 forum do this with a bread tie.
 
quote=Thevmaxrider;48831]Oh yeah, and it pulls all the way up...... HARD!!!!!!!!!!!!!!!!! Will have the 3" over swing arm and the front is lowered 2.5" so front end should stay down too.[/quote]



:eusa_dance:
I can feel some high 1.30's ' low 1.40's 60ft times @ 10.20's

Put me against Cornball on your Monster :boxing00: I wont let the site down.
 
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