1965 Pontiac GTO

1965 Pontiac GTO Mod Guide

• 335 HP / 431 lb-ft • RWD

335 stock HP
13 parts
4 categories

Best Performance Mods for the 1965 Pontiac GTO

Looking to get more power out of your Pontiac GTO? We've cataloged 13 performance parts across 4 categories with real-world HP and torque gains.

The biggest single gain? The Edelbrock Edelbrock 60509: Edelbrock Performer RPM Cylinder Heads (Cylinder Heads) adds +55 HP on its own.

Build yours in the interactive builder →

Exhaust (Cat-Back)

Cat-back and axle-back exhaust systems

Pypes Performance Exhaust SGA11: Pypes No-Muffler Exhaust Systems

Pypes Performance Exhaust Pypes Performance Exhaust SGA11: Pypes No-Muffler Exhaust Systems

+12 HP +15 lb-ft
$682.79

Pypes Performance Exhaust SGA11: Exhaust System, No-Muffler, Header-Back, Stainless Steel, Natural, Buick, Chevy, Oldsmobile, Pontiac, V8, Kit - Pypes No-Muffler exhaust systems are designed to delive

AI estimate
Buy at Summit Racing
Pypes Performance Exhaust SGA14: Pypes No-Muffler Exhaust Systems

Pypes Performance Exhaust Pypes Performance Exhaust SGA14: Pypes No-Muffler Exhaust Systems

+12 HP +15 lb-ft
$759.79

Pypes Performance Exhaust SGA14: Exhaust System, No-Muffler, Header-Back, Stainless Steel, Natural, Buick, Chevy, Oldsmobile, Pontiac, V8, Kit - Pypes No-Muffler exhaust systems are designed to delive

AI estimate
Buy at Summit Racing
Pypes Performance Exhaust SGA14SS: Pypes No-Muffler Exhaust Systems

Pypes Performance Exhaust Pypes Performance Exhaust SGA14SS: Pypes No-Muffler Exhaust Systems

+12 HP +15 lb-ft
$1,216.79

Pypes Performance Exhaust SGA14SS: Exhaust System, No Mufflers, Header-Back, Polished Stainless Steel, X-Pipe, Buick, Chevy, Olds, Pontiac, V8 - Pypes No-Muffler exhaust systems are designed to delive

AI estimate
Buy at Summit Racing
Flowmaster 81073: Flowmaster Manifold Downpipes

Flowmaster Flowmaster 81073: Flowmaster Manifold Downpipes

+8 HP +12 lb-ft
$306.95

Flowmaster 81073: Intermediate Pipes, Manifold Downpipe, Stainless Steel, Natural, 2.50 in. O.D., Pontiac, Pair - Flowmaster manifold downpipes are designed for the person who wants to use a crossmemb

AI estimate
Buy at Summit Racing
Flowmaster 1041: Flowmaster Pipe Kits

Flowmaster Flowmaster 1041: Flowmaster Pipe Kits

+6 HP +10 lb-ft
$562.95

Flowmaster 1041: Exhaust System, Header-Back, Pipe Kit Only, Buick, Chevy, Oldsmobile, Pontiac, Steel, Aluminized, Kit - Flowmaster pipe kits are just like the Flowmaster exhaust systems except they d

AI estimate
Buy at Summit Racing

Headers/Manifold

Long tube and shorty headers

Kooks Headers 29202400: Kooks Headers Race Long Tube Headers

Kooks Headers Kooks Headers 29202400: Kooks Headers Race Long Tube Headers

+18 HP +22 lb-ft
$1,136.18

Kooks Headers 29202400: Headers, Long Tube, Stainless Steel, Natural, 1.875 in. Tube, 3.00 in. Collector, Chevy, LSX Small Block - Kooks Headers race long tube headers will deliver high performance to

AI estimate
Buy at Summit Racing
Flowmaster 814116: Flowmaster Scavenger Series Elite Headers

Flowmaster Flowmaster 814116: Flowmaster Scavenger Series Elite Headers

+16 HP +20 lb-ft
$1,199.95

Flowmaster 814116: Headers, Scavenger Series Elite, Long Tube, Stainless, Polished Ceramic Coated, Chevy, LS Engine, Pair - These Flowmaster Scavenger Series Elite headers open up airflow for serious

AI estimate
Buy at Summit Racing

Downpipe

Catted and catless downpipes

Flowmaster 81073: Flowmaster Manifold Downpipes

Flowmaster Flowmaster 81073: Flowmaster Manifold Downpipes

+8 HP +12 lb-ft
$306.95

Flowmaster 81073: Intermediate Pipes, Manifold Downpipe, Stainless Steel, Natural, 2.50 in. O.D., Pontiac, Pair - Flowmaster manifold downpipes are designed for the person who wants to use a crossmemb

AI estimate
Buy at Summit Racing

Cylinder Heads

Ported and performance heads

Edelbrock 60509: Edelbrock Performer RPM Cylinder Heads

Edelbrock Edelbrock 60509: Edelbrock Performer RPM Cylinder Heads

+55 HP +70 lb-ft
$976.50

Edelbrock 60509: Cylinder Head, Performer RPM, Aluminum, Bare, 72cc Chamber, 215cc, Pontiac, Semi Finished, 389-455, Each - Edelbrock Performer RPM aluminum cylinder heads feature threaded inserts in

AI estimate
Buy at Summit Racing
Edelbrock 60589: Edelbrock Performer RPM Cylinder Heads

Edelbrock Edelbrock 60589: Edelbrock Performer RPM Cylinder Heads

+55 HP +70 lb-ft
$914.50

Edelbrock 60589: Cylinder Head, Performer RPM, Aluminum, Bare, 72cc Chamber, 215cc Intake Runner, Pontiac, 389-455, Each - Edelbrock Performer RPM aluminum cylinder heads feature threaded inserts in t

AI estimate
Buy at Summit Racing
Edelbrock 60599: Edelbrock Performer RPM Cylinder Heads

Edelbrock Edelbrock 60599: Edelbrock Performer RPM Cylinder Heads

+55 HP +70 lb-ft
$1,365.50

Edelbrock 60599: Cylinder Head, Performer RPM, Aluminum, Assembled, 72cc Chamber, 215cc Intake Runner, Pontiac, 389-455, Each - Edelbrock Performer RPM aluminum cylinder heads feature threaded inserts

AI estimate
Buy at Summit Racing
Edelbrock 60575: Edelbrock Performer Cylinder Heads

Edelbrock Edelbrock 60575: Edelbrock Performer Cylinder Heads

+45 HP +55 lb-ft
$1,405.50

Edelbrock 60575: Cylinder Head, Performer, Aluminum, Assembled, 87cc Chamber, 215cc Intake Runner, Pontiac, 389-455, Each - All Edelbrock aluminum cylinder heads feature threaded inserts in the rocker

AI estimate
Buy at Summit Racing
Edelbrock 60579: Edelbrock Performer Cylinder Heads

Edelbrock Edelbrock 60579: Edelbrock Performer Cylinder Heads

+45 HP +55 lb-ft
$1,365.50

Edelbrock 60579: Cylinder Head, Performer, Aluminum, Assembled, 87cc Chamber, 215cc Intake Runner, Pontiac, 389-455, Each - All Edelbrock aluminum cylinder heads feature threaded inserts in the rocker

AI estimate
Buy at Summit Racing

Ready to build?

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