HEI. What do I need?

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

landtoy80 said:
If you remove the EGR don't you have to back off the max advance a bit?
JimC said what the max was for a desmogged motor but that was some time ago.
Click to expand...
The max for an FJ60 at sea level is 36deg. As altitude increses, cylinder pressure decreases, requiring an earlier ignition event.

Redneck rule of thumb:
add 1 degree for every 1K in altitude above 1K. i.e. 1 degree at 2K, 2 degrees at 3k...9deg @ 10K

I have to go to work now. See y'all later :cheers:
 
FJ40Jim said:
The max for an FJ60 at sea level is 36deg. As altitude increses, cylinder pressure decreases, requiring an earlier ignition event.

Redneck rule of thumb:
add 1 degree for every 1K in altitude above 1K. i.e. 1 degree at 2K, 2 degrees at 3k...9deg @ 10K

I have to go to work now. See y'all later :cheers:
Click to expand...

Jim, thanks, great info. Thanks for posting it up !!! I thought max degrees was in the mid-30 degree range just couldn't pin down the exact number.

:cheers:

Cahil
 
<<<You do not want to use the VTV on the vacuum advance hose with the HEI dist or you will have knock problems.
Actually, the VTV will reduce knock problems by slowing down the vac advance.>>>

Hi Jim, didn't know you were on this board.

I may be way off and slap me if I am wrong( I don't have the 87FJ60 or the FSM any more)
BUT
Looking in the Haynes and from what I remember the VTV would let vacuum get to the dist, advance it, and hold it there when there was no longer vacuum from the carb.
The VTV has a dark (side B) and a light (side A) side.
Per the Haynes it says to check the VTV
"Check to see that air flows from B to A but is does not flow from A to B"

THe way the VTV is on the vacuum hose it that side B is towards the dist and side A is towards the carb.
Thus vacuum can advance the dist when you open the throttle. When the throttle is closed there is a delay before you loose vacuum to the dist.

If you had the VTV on the wrong way (I had it hooked up the wrong way for some time and had NO vacuum advanve) you would have no vacuum advance.

Maybe there is more vacuum advance on the HEI dist so having the vacuum advance held for a short time is to much advance, thus causing knock.

When I removed the VTV, I no longer had knock when going driving in the hills.

So If I have this right:
When the throttle is closed, there is no vacuum to the vacuum advance.
WHen the throttle is open, there is vacuum to the vacuum advance.
With the VTV, the vacuum advance is advanced for a short time after there is no longer vacuum.

Let the "slapping" begin :flipoff2:

Jim didn't you tell me that the max advance needed to be less when you remove the EGR?
 
landtoy80 said:
<<<You do not want to use the VTV on the vacuum advance hose with the HEI dist or you will have knock problems.
Actually, the VTV will reduce knock problems by slowing down the vac advance.>>>

I may be way off and slap me if I am wrong( I don't have the 87FJ60 or the FSM any more)
Click to expand...

(in best MTV voice) Yo! You been slapped!

<<Looking in the Haynes and from what I remember the VTV would let vacuum get to the dist, advance it, and hold it there when there was no longer vacuum from the carb. Thus vacuum can advance the dist when you open the throttle. When the throttle is closed there is a delay before you loose vacuum to the dist.>>

That is incorrect. See page 3-11, "2F Engine Emission Control Service Manual".
Vacuum is slowly applied to the advancer to prevent the engine from making full power and generating NOx gas.

<<THe way the VTV is on the vacuum hose it that side B is towards the dist and side A is towards the carbIf you had the VTV on the wrong way (I had it hooked up the wrong way for some time and had NO vacuum advanve) you would have no vacuum advance.>>

Yes, the stock setup is calibrated for reduced emissions, not best efficiency.

<<So If I have this right:
When the throttle is closed, there is no vacuum to the vacuum advance.
WHen the throttle is open, there is vacuum to the vacuum advance.
With the VTV, the vacuum advance is advanced for a short time after there is no longer vacuum.>>

Yes, yes, no.

<<Jim didn't you tell me that the max advance needed to be less when you remove the EGR?>>

Yes. See previous posts.
 
I found the evil VTV. Its blue on one side (side A) and brown on the other side (side B).
Unless the Haynes manual is wrong, it says to install the VTV brown side "B" towards the dist.
So that means side A (the blue side) is towards the intake.

I hooked up the VTV up to a vacuum guage with side B hooked up to a vacuum guage.
I sucked the blue side "A".
The guage went up freely. When I stopped sucking the guage slowly went down.

When I reverse the VTV, side "A" towards the guage.
The guage slowly goes up and drops right when I stop sucking.
Note: the wife wants to know why I am kissing the VTV :rolleyes: :D
 
OK. just to let you know whats going on my base timing is at 12deg. When I hook up the HAC from manifold vac it immediatly goes up to 16deg. Then with the ported vac from the carb hooked up to the other main advance port it has a total of 40 deg at 3500rpm. It is running good and not pinging under a load so maybe I'll advance it a little more and go from there.
 
I found the evil VTV. Its blue on one side (side A) and brown on the other side (side B).
Unless the Haynes manual is wrong, it says to install the VTV brown side "B" towards the dist.
So that means side A (the blue side) is towards the intake.
I hooked up the VTV up to a vacuum guage with side B hooked up to a vacuum guage.
I sucked the blue side "A".
The guage went up freely. When I stopped sucking the guage slowly went down.
When I reverse the VTV, side "A" towards the guage.
The guage slowly goes up and drops right when I stop sucking.

Note: the wife wants to know why I am kissing the VTV :rolleyes: :D
Click to expand...
Yes, Haynes is wrong. The VTV is there to delay application of distributor vacuum. See the FSM for troubleshooting and installation of spark control system.

You are kissing Cruiser parts 'cause you love 'em. :D
 
You must log in or register to reply here.

Share this page

Back
Top Bottom