496ci revamped

Speedlink1973 said:
So if it pulls 7 ish with standard rings
I could possibly sneak by because of the total seal gapless rings?
Maybe gapless rings will be a double duty plus
Click to expand...
Too many Variables unknown.
Wishful thinking present by us.

My old 70 TA is a Muncie 4 speed.
Throw any cam at it does not matter.
The Factory Power brake booster was designed for low engine vacuum.
Never had issues. Always power brakes .
No Crane vacuum can used.
May be 1970 only Power brake booster.
Never researched.
Just works.
 
from the few guys I know that have flow tested pro-comps heads I think thats very optimistic,
UNLESS you take the time to do rather extensive port & bowl area clean-up porting


the pro comps are NOT irredeemable with proper port and bowl clean-up and a decent valve job they can be made to run decently, but by the time you put the required parts and labor into the project its cheaper and faster to buy a better head like AFR or BRODIX, TRICKFLOW, profiler or even some EDELBROCK BBC HEADS, remember you tend to get what you pay for, to some extent and better quality parts and more precise labor, tends too cost more too assemble and sell


related info
http://garage.grumpysperformance.com/index.php?threads/port-speeds-and-area.333/

http://garage.grumpysperformance.com/index.php?threads/sellecting-cylinder-heads.796/

http://garage.grumpysperformance.com/index.php?threads/porting-can-help.462/

http://garage.grumpysperformance.com/index.php?threads/big-block-head-comparison.319/

http://garage.grumpysperformance.com/index.php?threads/aftermarket-heads-for-a-bbc.12316/

http://garage.grumpysperformance.co...n-chamber-or-piston-dome-or-port-volume.2077/

http://garage.grumpysperformance.com/index.php?threads/should-you-buy-bare-or-assembled-heads.534/

http://garage.grumpysperformance.com/index.php?threads/big-block-pushrod-guide-plates.4596/

http://garage.grumpysperformance.com/index.php?threads/valve-springs.9613/


the valves leaking seems to be a recurring theme from everyone testing them out of the box
and from what I read in several places this is an example (the larger port head)

To be blunt, other than the valve job, the Procomp head has enough fairly "ugly" things about it that I skipped even bothering to do a "before" flow test and grabbed the Makita. However, after having some questions re: the results, I picked the best looking (minimal casting flash, best short turn, etc.) of the clone's remaining three unported intake runners and picked the #3/6 for an �out-of-the-box plus a good valve job� test. That's shown in column A. This is the best I can do at this point to provide a �before� test.

Column B is the results from the first round of what I referred to as �basic prep� on #5/4 based on what looked to need work. This consisted of trimming down some big �humps� in the as-cast walls, cleaning up (but not reprofiling) the SSR, blending the valve job into the bowl, narrowing the guide, working the transition from the seat insert into the SSR, blending the CNC'd port opening, and touching up the chamber where the valve job had a stepped transition into it.

Column C is the results from doing some additional work to #5/4, such as widening the short turn, opening the wall near the plug more, and opening the bowl deeper on the exhaust-side of the port. Also, until now everything was primarily a cuttered finish, but I hit the reworked SSR w/ a 60-grit flapper and cleaned up the bowl w/ a 60-grit roll. No actual runner enlargement over the original design size was ever done.

Column D is the improvement between A and C, FWIW.

Lift ------ A ----- B ------ C ----- D
.050 --- 33.8 --- 31.6 --- 32.0 --- (1.8 )
.100 --- 67.6 --- 65.9 --- 66.7 --- (.9)
.200 -- 136.7-- 139.7 -- 141.6 --- 4.9
.300 -- 192.6 -- 202.4 -- 206.6 -- 14.0
.400 -- 245.2 -- 259.5 -- 264.3 -- 19.1
.450 -- 265.8 -- 281.8 -- 287.1 -- 21.3
.500 -- 287.1 -- 302.2 -- 303.9 -- 16.8
.550 -- 293.8 -- 317.0 -- 318.7 -- 24.9
.600 -- 304.5 -- 325.8 -- 325.8 -- 21.3
.650 -- 313.4 -- 333.1 -- 331.2 -- 17.8
.700 -- 315.2 -- 338.8 -- 337.0 -- 21.8

Something in the latest changes have begun to trade off .300-.500" improvements for small decreases above .600".
Click to expand...
 
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Grumpy said:
from the few guys I know that have flow tested pro-comps heads I think thats very optimistic,
UNLESS you take the time to do rather extensive port & bowl area clean-up porting

the valves leaking seems to be a recurring theme from everyone testing them out of the box
and from what I read in several places this is an example (the larger port head)
Click to expand...
And that why you pay 3k for a set of heads and not 1k For a set of heads, but like anything else with time and money you could probably spruce them up to some degree,
But if you run into a bunch of porosity
Trying to dig them out could be bad unless you're a good aluminum welder.
You can eat up a bunch of time fiddling around with ports and heads.
 
Grumpy said:
https://www.summitracing.com/parts/...MI49uG9ZSr3AIVEdbACh0XWgzJEAQYAyABEgIN-fD_BwE
Click to expand...
That takes care of just the power brakes Grumpy.
Not the 4L80E.
Reason why the Vacuum modulator takes the place of the Line pressure control solenoid EPC.

Has to follow a smooth linear curve.
Or the Clutches will slip.

Steady predetermined line pressure rise.
Could go full line pressure.
May beat up the aluminum cases 4L80e to death.

Turbo 400 has the aftermarket REID CASE for Severe duty applications.
Constant lime pressure.
 
We don't know all the engineering behind the Transgo 4L80E-3.

Black Magic.

Only place I know to get answers is FB.
TRANSMISSION 101.
I am in it.
 
This is where the vacuum was
Don't know if it helps answer any questions or not being it's at 4200 rpms
As far as 4l80goes
181520.jpg


index.php
 

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Got a call in to guy who built transmissions on vacuum and 4l80
He built this for 850 hp
And builds 1500 hp next step up
I wouldn't think you would be running a small cam on 1500 hp big blocks
Grumpy you may have heard of this guy
He's out of Tampa area
Animal performance
Tony Vargas
 
Speedlink1973 said:
Got a call in to guy who built transmissions on vacuum and 4l80
He built this for 850 hp
And builds 1500 hp next step up
I wouldn't think you would be running a small cam on 1500 hp big blocks
Grumpy you may have heard of this guy
He's out of Tampa area
Animal performance
Tony Vargas
Click to expand...
We have a unique situation.
If you have a Facebook account join Transmission 101 group.
Take 1-2 days to get in.
The Pros are on it daily from around the world.
A Transgo Rep I have talked to about his Transgo Turbo 400 Pro Shift Kit I have.
He answered.

Cussing at times.
So not always family friendly.
Give you the link.
I can start a thread there if you like.
 
Maniacmechanic1 said:
Too many Variables unknown.
Wishful thinking present by us.

My old 70 TA is a Muncie 4 speed.
Throw any cam at it does not matter.
The Factory Power brake booster was designed for low engine vacuum.
Never had issues. Always power brakes .
No Crane vacuum can used.
May be 1970 only Power brake booster.
Never researched.
Just works.
Click to expand...
 

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Maniacmechanic1 said:
We have a unique situation.
If you have a Facebook account join Transmission 101 group.
Take 1-2 days to get in.
The Pros are on it daily from around the world.
A Transgo Rep I have talked to about his Transgo Turbo 400 Pro Shift Kit I have.
He answered.

Cussing at times.
So not always family friendly.
Give you the link.
I can start a thread there if you like.
Click to expand...

Maniacmechanic1 said:
I think you have a dual piston diaphragm booster.

Mine is huge single style.
Like off a truck size.
Click to expand...
Yes, exactly what it is
 
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