Do you guys know what I may be stepping into here regarding max lift without machine work on these heads? Casting #10114156. The other number is K067.
I'm trying to upgrade an otherwise stock 454 but I have no flippin idea where I can go with lift on these factory heads.
Thank you!
Help With BBC Castings
Moderator: Team
Re: Help With BBC Castings
we need all the details on your build and application
but
just do a search on that casting number
example
http://www.performanceboats.com/jet-boa ... -good.html
10114156...91-up...oval...OPEN chamber. ..Gen.V & VI Blocks 454, 118cc chamber 2.06 Intake Valve
Those are "peanut" port heads, not for performance. (peanut port heads have been made to work for some applications)
Before you consider swapping heads,
check the block casting number as the Gen 5 blocks are not good for putting MK IV or aftermarket heads on. (can be made to work)
Gen 6 works with better variety of heads.
Don't plan on just adding a different set of heads and gaining a bunch of power, the cam needs to match your application to make it all work (always true)
http://forums.superchevy.com/chevy-high ... v-engines/
but
just do a search on that casting number
example
http://www.performanceboats.com/jet-boa ... -good.html
10114156...91-up...oval...OPEN chamber. ..Gen.V & VI Blocks 454, 118cc chamber 2.06 Intake Valve
Those are "peanut" port heads, not for performance. (peanut port heads have been made to work for some applications)
Before you consider swapping heads,
check the block casting number as the Gen 5 blocks are not good for putting MK IV or aftermarket heads on. (can be made to work)
Gen 6 works with better variety of heads.
Don't plan on just adding a different set of heads and gaining a bunch of power, the cam needs to match your application to make it all work (always true)
http://forums.superchevy.com/chevy-high ... v-engines/
Re: Help With BBC Castings
If you have the head there on hand you can check the valve lift travel before the retainer bottom hits the installed valve seal, yourself.
Remove the spring, push the seal down on the guide if it has lifted, reassemble without the spring and check
availbe travel..
Usually it is the stock bbc rocker slot that is the limiter.
Typically a common .540" lift perf hyd cam fits.
You will need to vrrify for your self.
Remove the spring, push the seal down on the guide if it has lifted, reassemble without the spring and check
availbe travel..
Usually it is the stock bbc rocker slot that is the limiter.
Typically a common .540" lift perf hyd cam fits.
You will need to vrrify for your self.
Re: Help With BBC Castings
If the head has ex rotators it effects things.
Some of the stock bbc springs coil bind easy and are not suited to any + valve lift over stock.
oem non adj bbc rockers will need conversion,/ upgrade.. springs too.
Some of the stock bbc springs coil bind easy and are not suited to any + valve lift over stock.
oem non adj bbc rockers will need conversion,/ upgrade.. springs too.
Re: Help With BBC Castings
I had a feeling that he stepped on both of our dicks when he picked up this Mk5. Dammit!
Re: Help With BBC Castings
You think .540 will be safe, Fbird?
I'm eyeballing a Bullet 224/232 at .050, .520/.495 lift, 106 LSA, hyd/flat cam and it's only for the summer. He's got some stuff to sort out with the car (C3 Corvette) before we do a full build over the winter.
As he calls it "a throw-away cam" that's temporary.
I'm eyeballing a Bullet 224/232 at .050, .520/.495 lift, 106 LSA, hyd/flat cam and it's only for the summer. He's got some stuff to sort out with the car (C3 Corvette) before we do a full build over the winter.
As he calls it "a throw-away cam" that's temporary.
Re: Help With BBC Castings
I think you can and should measure for yourself before buying any cam for this motor..
It will be real temperary if things stack solid.
You can measue it right on the assembled motor using the valve spring compressor leverage tool and a dial gauge..
valve closed, valve cover off.
Or just quick pop a spring or 2 off with that simple $5 spribg compress tool.
This is stuff yu should not need to ask..
If the stock rocker are net- none adj and the cam has mire than stock lift, the difference shows up in rocker preload.
As the increased lift comes off the base side of the new cam lobe.
Are these non adj bbc rockers?
If so plan on rework, replace and new springs and seat cups and shims if rotators are removed too.
Many bbc truck motors have ex rotators and non adj rockers.
It will be real temperary if things stack solid.
You can measue it right on the assembled motor using the valve spring compressor leverage tool and a dial gauge..
valve closed, valve cover off.
Or just quick pop a spring or 2 off with that simple $5 spribg compress tool.
This is stuff yu should not need to ask..
If the stock rocker are net- none adj and the cam has mire than stock lift, the difference shows up in rocker preload.
As the increased lift comes off the base side of the new cam lobe.
Are these non adj bbc rockers?
If so plan on rework, replace and new springs and seat cups and shims if rotators are removed too.
Many bbc truck motors have ex rotators and non adj rockers.
Re: Help With BBC Castings
A off the shelf comp thumpr hyd cam will suite the purpose.
has modrrate lift and desired tight 107 lsa.
Grwat if the stock cr is low.
has modrrate lift and desired tight 107 lsa.
Grwat if the stock cr is low.
Re: Help With BBC Castings
The key to sucess with the thumpr rabbit cams is doing the correct required distributor advance curve
so the new 107 lsa cam idles and drives right.
Your bullet cam choice will be same same..
recurve the diz for a short limited 10-12 deg mech adv curve..
allows 24 26 deg base initial, 10-12 deg adv curve 36-38 max total adv @wot..
limit vac adv to 10-15 deg and use ported vac on the carb.
Comp does not explain this setup change for these cams,
creating needless enduser tuning and dissatisfaction issues
with these cams.
When the setup is redone right it will run great, and actually add power and torque as intended.
The intended modest valve lift is a plus for easy install on stock, near stock street stuff.
Yoyr cam will be same same.. so....
so the new 107 lsa cam idles and drives right.
Your bullet cam choice will be same same..
recurve the diz for a short limited 10-12 deg mech adv curve..
allows 24 26 deg base initial, 10-12 deg adv curve 36-38 max total adv @wot..
limit vac adv to 10-15 deg and use ported vac on the carb.
Comp does not explain this setup change for these cams,
creating needless enduser tuning and dissatisfaction issues
with these cams.
When the setup is redone right it will run great, and actually add power and torque as intended.
The intended modest valve lift is a plus for easy install on stock, near stock street stuff.
Yoyr cam will be same same.. so....
Re: Help With BBC Castings
On qjets and afb carbs change the pri metering rod power piston spring. to keep the pri metering rods down in jets
at idle, in gear as the cams lower idle vac in gear effects this.
On a holley change the piwer valve vac rating. 3.5" or 4.5" vac rated usually.
This stablizes the idle in gear with these cams.
Again your 106 lsa bullet cam will be same.
You can get the qjet tuning parts from edelbrock.
at idle, in gear as the cams lower idle vac in gear effects this.
On a holley change the piwer valve vac rating. 3.5" or 4.5" vac rated usually.
This stablizes the idle in gear with these cams.
Again your 106 lsa bullet cam will be same.
You can get the qjet tuning parts from edelbrock.