pontiac help
- Thread starter qiksix
- Start date
MRKING
New Parts for Old Trucks
Re: pontiac help
Fully ported Pontiacs imo .
Either set will be expensive to get road ready . As far as specs etc , its all been covered pretty well over the past 10 years , sometimes you have to just keep digging .
If you cant find what they need to work properly at the hp level they can put you at , they may not be needed in your build . Unless you have a strong low 10 sec truck being built , other heads can get you where youd like to be .
What are you trucks goals ?
Fully ported Pontiacs imo .
Either set will be expensive to get road ready . As far as specs etc , its all been covered pretty well over the past 10 years , sometimes you have to just keep digging .
If you cant find what they need to work properly at the hp level they can put you at , they may not be needed in your build . Unless you have a strong low 10 sec truck being built , other heads can get you where youd like to be .
What are you trucks goals ?
Re: pontiac help
I'm in Australia and engine is in a 2200lb drag car. Engine specs are;
stock block
std stroke crank
h beam rods
dome top pistons(14:1)
comp solid roller 649/632 & 263/276 @ 050
hilborn methanol injection
I have the bowties on and just cracked another port wall for 2nd time, trying to decide wether fix again or go for new heads. Not much in the way of parts over here i can get pontiacs but can ship from US if need be.
Steve
I'm in Australia and engine is in a 2200lb drag car. Engine specs are;
stock block
std stroke crank
h beam rods
dome top pistons(14:1)
comp solid roller 649/632 & 263/276 @ 050
hilborn methanol injection
I have the bowties on and just cracked another port wall for 2nd time, trying to decide wether fix again or go for new heads. Not much in the way of parts over here i can get pontiacs but can ship from US if need be.
Steve
warmpancakes
New member
Re: pontiac help
the pontiacs wont work with stock block
the pontiacs wont work with stock block
warmpancakes
New member
Re: pontiac help
they require a bore size larger than a stock block will go, gerber explained it to me the other day
they require a bore size larger than a stock block will go, gerber explained it to me the other day
Windedv6
Ty n 10s
Re: pontiac help
The valve spacing is wider with the Pontiac and 18* heads You would have to relief the cylinder wall in the area of the valve on the small bore motor. You can do that safely in a small bore bowtie block because of more material avaialble, but its not recommended in a stock block. Some times there is Pontiac heads floating around that have smaller valves that may work with stock blocks, but your still running the valve close to the wall. Not so good with the air flow into the cylinders, but not as noticeable with a boosted motor as with an NA motor.
Depending on the set of heads you get you may also have chamber sizing issues. A lot of after market heads have the chambers opened up for big bore blocks (4.125 - 4.180" range) which can cause issues with smaller bore blocks. I have seen where ppl use head gaskets to fit the bore and don't consider the chamber width. Always check both and get gaskets setup for the largest dia fo the two.
John
The valve spacing is wider with the Pontiac and 18* heads You would have to relief the cylinder wall in the area of the valve on the small bore motor. You can do that safely in a small bore bowtie block because of more material avaialble, but its not recommended in a stock block. Some times there is Pontiac heads floating around that have smaller valves that may work with stock blocks, but your still running the valve close to the wall. Not so good with the air flow into the cylinders, but not as noticeable with a boosted motor as with an NA motor.
Depending on the set of heads you get you may also have chamber sizing issues. A lot of after market heads have the chambers opened up for big bore blocks (4.125 - 4.180" range) which can cause issues with smaller bore blocks. I have seen where ppl use head gaskets to fit the bore and don't consider the chamber width. Always check both and get gaskets setup for the largest dia fo the two.
John
ed hess
race or get outta the way
Re: pontiac help
Dont understand this requirment to have an oversize bore, beyond the max bore for a stock block. Granted I have a bowtie block but its only 4.030. I recall mapping the gasket bore id to the head and the combustion chamber od is not overhanging the block bore id.
then again my pontiac heads were angle milled also, but if the above id's & od's dont measure out wrong then i dont see what the issue is.
I'd like to hear more on this since I dont have problems unless its because we angle milled mine.
ed
Dont understand this requirment to have an oversize bore, beyond the max bore for a stock block. Granted I have a bowtie block but its only 4.030. I recall mapping the gasket bore id to the head and the combustion chamber od is not overhanging the block bore id.
then again my pontiac heads were angle milled also, but if the above id's & od's dont measure out wrong then i dont see what the issue is.
I'd like to hear more on this since I dont have problems unless its because we angle milled mine.
ed
ed hess
race or get outta the way
Re: pontiac help
how much?
beats me, but jesel only has one part number in their catalog for these pontiac heads, using comp solid roller lifters which have an offset also.
how much?
beats me, but jesel only has one part number in their catalog for these pontiac heads, using comp solid roller lifters which have an offset also.