Econo Big Block Question
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Joined: Feb 2002
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From: Alberta
Econo Big Block Question
Has anyone out there put truck heads on a 454 with good results for a fast street machine with big torque.
GM Chevy big block heads are basically rectangular port (hi perf), oval port (standard low perf) and small oval (truck).
Supposedly the oval ports are good to 6500 rpm's while the truck heads are so limited in port size that 5000 is about it.
But maybe a combination like this could have great throttle response and gobs of torque allowing for a lower rear axle ratio and better highway cruising with a four speed without od. And cheap !
The key to this question is STREET..........I know that for serious power and drag racing this is NOT it.
GM Chevy big block heads are basically rectangular port (hi perf), oval port (standard low perf) and small oval (truck).
Supposedly the oval ports are good to 6500 rpm's while the truck heads are so limited in port size that 5000 is about it.
But maybe a combination like this could have great throttle response and gobs of torque allowing for a lower rear axle ratio and better highway cruising with a four speed without od. And cheap !
The key to this question is STREET..........I know that for serious power and drag racing this is NOT it.
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Not worth the trouble unless you take lots of metal out of the ports. They are just too small.
You never want to create a TQ monster with the characteristics of a diesel. Lots of folks go way overboard on this "TQ is everything" concept. TQ is everything...but TQ over a broad RPM range is what you want.
Build enough low end to do what is needed...and feed it enough air to support it as rpm climbs. Nothing worse that driving a motor that "runs out of air" too early.
I like them to still be pulling hard when I shift! Not nosing over.
If the tires are spinning..you have enough TQ....build it for TQ at a higher rpm.
JIM
You never want to create a TQ monster with the characteristics of a diesel. Lots of folks go way overboard on this "TQ is everything" concept. TQ is everything...but TQ over a broad RPM range is what you want.
Build enough low end to do what is needed...and feed it enough air to support it as rpm climbs. Nothing worse that driving a motor that "runs out of air" too early.
I like them to still be pulling hard when I shift! Not nosing over.
If the tires are spinning..you have enough TQ....build it for TQ at a higher rpm.
JIM
