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Sat Apr 17, 2021 10:59 pm

ivkings4 wrote:

also my 88mm Marine crank was ordered Friday. I dont know any of the details just it will be a 88 and it takes 6 months to get.

Shawn said 88 X 103 or 105

I will be driving it home tomorrow, not the flatbed like last time.

Size of main /journals on Marine crankshaft?

What rods you going with now?

Tks

Sun Apr 18, 2021 3:02 pm

Like I said I have no details on the crank, only the brand and size, 88 flanged Marine. I have no clue what shawn does for bearing size or rods. I left it up to him,

As far as brakes it is 1200 per axle (might of gone up) The master is 250.00 the lines are about 150 per axle (300 total) The strange and wilwood are the same or close to it. The spindles that RLR makes is the big difference and how light the rotors are compared to empi.

Sun Apr 18, 2021 4:04 pm

Tks Robert👊

Mon Apr 19, 2021 9:19 am

So the cruise went well for the most.

The idle jet change gave me a stumble at transition. It was in the 13 to 14 afr everywhere but at transition it went up to 15 and stumbled. no big deal, I have a 40' 5th wheel in my driveway for 2 weeks, (in laws visiting) so Its hard to take the car for a test drive for each change I make. I will mess with it later today

The temp outside was 88. oil got to 225 up some hills and that was it, cooled down to 205 at stop lights.

My #2 carb pulls less air then the other 3, has been that way for ever, or since Jaycee did the carbs the first time. Gary Berg was at the carbs and coffee, he said to use the wrench method and try to bend the shaft so they read the same. He said he does it all the time.

I did it and when I run it today I will see if it fixed it. It would read 2 lower on the snail then the other 3. when tuning I would need more turns out on idle/air screw on that hole.

I tried to record the drive home on the lm2 but forgot to stop the recording before I turned the key off and lost the data. I wanted to see the head temps. with the wife in the car the laptop stays home.

Mon Apr 19, 2021 9:31 am

Can you explain the wrench method to tweak the butterfly?

Mon Apr 19, 2021 9:42 am

I was hoping someone else would.

Jiminez tried to when my engine was on his dyno 3 years ago and I watched him, I had one butterfly 2mm smaller than the other 3 at that time. He did not know that so he tried to fix it.

He put a crescent wrench on each nut at the end of the throttle shaft, then he turned one one way and the other one opposite, if that makes sense. twisting the shaft to correct the issue.

Experts please correct me as I just watched him and this was 3 years ago. If there is something i missed or forgot please add to this??

Mon Apr 19, 2021 9:52 am

The "wrench" method is to bend the "Z" bend pushrods that come with the Berg linkage to get the carbs sync'd. you either straighten, or increase the "Z" bend to make micro adjustments.
A hammer would work the same.

So much easier to use Left/right threaded pushrods. IDA's are so sensitive to sync. I like the micro adjustments that L/R hand thread give.
I have found a 1/8" turn on the pushrod is the difference between smooth running, and crap.

NOthing worse to drive than out of sync IDA's.
Most folks blame the IDA as a "not street friendly" carb.
I dis-agree with that. They are just so big and sensitive to even the slightest out-of-sync opening. Many folks simply lack the patients or skills to get them in perfect sync.

I have seen plenty of folks dump the Z bend rods and use stock VW pushrods threaded in each end with L/R threaded Heim joints.
No point to the Z bend anyways. A straight rod does the same job.

Not sure why the Berg linkage never evolved in this regard. It would make it so much easier to sync.

Mon Apr 19, 2021 10:01 am

Ohio Tom wrote: The "wrench" method is to bend the "Z" bend pushrods that come with the Berg linkage to get the carbs sync'd. you either straighten, or increase the "Z" bend to make micro adjustments.
A hammer would work the same.

So much easier to use Left/right threaded pushrods. IDA's are so sensitive to sync. I like the micro adjustments that L/R hand thread give.
I have found a 1/8" turn on the pushrod is the difference between smooth running, and crap.

NOthing worse to drive than out of sync IDA's.
Most folks blame the IDA as a "not street friendly" carb.
I dis-agree with that. They are just so big and sensitive to even the slightest out-of-sync opening. Many folks simply lack the patients or skills to get them in perfect sync.

I have seen plenty of folks dump the Z bend rods and use stock VW pushrods threaded in each end with L/R threaded Heim joints.
No point to the Z bend anyways. A straight rod does the same job.

Not sure why the Berg linkage never evolved in this regard. It would make it so much easier to sync.

I agree 100%

I’ve got ida’s in my baywindow bus and it drives lovely, not that much different to the IDF’s I had previously. As you say they take some careful jetting and balancing but are perfectly street friendly. Mine don’t have the 3rd progression hole mod either 8)

Mon Apr 19, 2021 10:23 am

My issue isn’t from the 1/2 side to the 3/4 side, or linkage would be an issue. It’s between the one and two cylinder or the throttle bar holding the two butterflies needs to be bent.

1/3/4 all read 6 on the snail. The 2 reads 4.

Mon Apr 19, 2021 10:30 am

yes the wrench method is as explained above, hold each end of the throttle shaft with a small wrench and twist opposite directions to get the throttle plates even.

much easier done with the carbs off the engine so you can visually see how the butterflies close. Its pretty obvious when you shine a flashlight from the top of the throat and look from the bottom.

BUT, before trying to wrench method, I always loosen the throttle plate screws and let the shafts snap close a few times to seat the throttle plates exactly where they want to go (original Italian weber/dellorto plates fit the bore pretty much perfectly, not letting ANY light through). Then tighten the screws.

of course with IDFs and DRLAs there is the idle air bleed, but thats another story..

Mon Apr 19, 2021 11:20 am

After the above has been done, close the throttle stop off completely and shine a torch into the throats from underneath. No light should be present when looking down each throat.

Mon Apr 19, 2021 7:36 pm

ok, So I pulled the carb. That way I could get a actual measurement. The #2 was .777 down the #1 was .787.

I pulled the nuts off each end of the shaft, that way I could grab the flat with a crescent wrench on each side and opened them up a 1/4 inch. then went right on one and left on the other then measured. took a few tries but got them .777 and .778. close enough

wont know till tomorrow if it worked, 8 people are in my driveway drinking beer and the car will disturb their vibe......

Tue Apr 20, 2021 8:22 am

they may of needed the vibe disturbed by sweet ride.....I know I do. :wink:

Tue Apr 20, 2021 11:48 am

with ITBs it’s common to use moly disulfate (spray moly). I spray enough into the lid, then use a paint brush to paint a ring at the edge of the throttle body and the plate. This seals the throttle to the bore. Then adjust idle speed out from there. Not sure if you can keep it out of the idle circuit on IDAs though.

This is a factory procedure for GTRs. They specifically recommend against using carb cleaner as it will wash the moly away. If you do, it needs to be reappliied. Fuel coming out of the booster might has the same effect as the carb cleaner too

Tue Apr 20, 2021 1:19 pm

HotStreetVw wrote: with ITBs it’s common to use moly disulfate (spray moly). I spray enough into the lid, then use a paint brush to paint a ring at the edge of the throttle body and the plate. This seals the throttle to the bore. Then adjust idle speed out from there. Not sure if you can keep it out of the idle circuit on IDAs though.

This is a factory procedure for GTRs. They specifically recommend against using carb cleaner as it will wash the moly away. If you do, it needs to be reappliied. Fuel coming out of the booster might has the same effect as the carb cleaner too

That is interesting!

Tue Apr 20, 2021 7:32 pm

74 Thing wrote: Can you explain the wrench method to tweak the butterfly?

A professional shop would put your carb on top of a intake manifold on a flow bench and bend the throttle shaft till each carb barrel flows the same. I do something similar at home with a vacuum cleaner and a modified single carb intake manifold. The manifold has a hole ground out just below the carb where each runner touches one another so then both barrels are exposed to the same vacuum pressure. I put this manifold in my bench vice, carb on top, vacuum cleaner on one side and the other side plugged.

Gary made some adapters out of plexiglass so that his shop vacuum nozzle fits into each adapter and he can use that to compare barrel to barrel.

A bent throttle shaft is really quite common as that shaft is more delicate than you might think. In order to bend it back you will have to remove the nuts on each end of the throttle shaft and possibly a washer or two in order to expose a big area of the flats. I then use two large adjustable wrenches as they have the most surface area to engage the flats of the shafts. With the throttle shaft held open part way, hold one side still and lightly twist the other side.

While doing the vacuum test you will need the idle speed set to a normal position, but as mentioned before to verify that your butterflies don't need to be re-centered on the shaft it is helpful to back the speed screw all the way out.

This will be trial and error, the goal is the twist the side that is letting light through when closed or has the higher reading on the snail gauge. It may help to back the idle speed screw out all the way so as you are checking your progress you can see how each butterfly closes. On my Dells, typically the lowest and smallest progression hole is ever so slightly exposed at idle and both sides will be exposed the same amount. Duplicate this and you will be close.

Be careful when you put the nuts, washers and any linkage pieces back on each end of the throttle shaft that you don't bend it again, if possible re-check you work before you put it back on the car.

Does that help?

Wed Apr 21, 2021 9:13 am

That's a great explanation. It's funny, I was thinking of building a manifold as you describe pretty much the same way.

Great idea!
Jeff

Wed Apr 21, 2021 6:11 pm

Mine are within a 1/2 or less on the snail now, very close.

Changed the idles back to a new set of 65's, the old ones were drilled.

65 idles and 100 holders. 12.5 afr at idle. 175 mains with 200 airs F2's 46 vents 31 total timing to 5500 then 32 up to 7700.

Runs like a top, if that really is something. I got the EGT's at idle to all be 800 to 840 and the cht's to be 280 to 320.

Crazy haw a small change in the idle/air screw moves the cht and the egt. you can actually hear the engine run smoother when the #s get closer together.

Wed Apr 21, 2021 7:13 pm

You guys are scaring me with all your throttle shaft bending.
But I’m aware of it ,
This is what you use if you want to be stupid dead on crazy

Wed Apr 21, 2021 9:25 pm

I agree Jim, that's why i haven't tried to bend them at all this entire time. I knew they were wrong all this time and I just tuned accordingly. Figured having it off was not helping the tune. When Gary Berg,(someone who does carb work for a living) said it was something he did when needed I figured what would it hurt.

When I have the carbs off next time I will have them fixed correctly.

I will be driving and tweaking the Tune for a week or 2 making small changes. Testing the new Drag radials I put on today, same as before 235/60/15 ET street's, got 4000 miles out of the last set.