Difference between 87 and 91 TPI base?
#1
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Difference between 87 and 91 TPI base?
I've got a friend who will sell me an 87 TPI intake base. I want to port the **** out of it, and have the old one unported as a standby just in case something happens. Is there a difference? I believe the 87 base would have a hole for the 9th injector, but does that make the swap impossible? What other differences are there? thanx
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91 Trans Am WS6
Bright White
5.0 TPI auto
Flowmaster 3" 2 chamber catback
Trans Go shiftkit
2000 stall converter
supposed 'peanut cammed' car (yeah, right)
Built on Wednesday
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91 Trans Am WS6
Bright White
5.0 TPI auto
Flowmaster 3" 2 chamber catback
Trans Go shiftkit
2000 stall converter
supposed 'peanut cammed' car (yeah, right)
Built on Wednesday
#2
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Car: '87 IROC-Z
Engine: 406 Superram/DFI
Transmission: Auto BTE 3000 conv
the injector is the only real difference. I think your '91 runners will cover it up enough to seal once you install them. Do a test fit tomake sure though.
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87 IROC-Z, 5.7, auto, 3.27, leather, !cat, Holley fpr, K&N'S, SLP 1-3/4" Jet-Hot coated headers, SLP .218/.224 .495/.502 cam, Comp 1.5 roller tip rockers, $uperPITAram, Edelbrock lower intake, Holley 52mm tb, Dynomax\Flowmaster catback. Coming Soon(?)- Fasttrack/Accell DFI
1989 Pontiac 20th Anniversary Turbo Trans Am - 161,000 miles, !cat, 9" K&N
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87 IROC-Z, 5.7, auto, 3.27, leather, !cat, Holley fpr, K&N'S, SLP 1-3/4" Jet-Hot coated headers, SLP .218/.224 .495/.502 cam, Comp 1.5 roller tip rockers, $uperPITAram, Edelbrock lower intake, Holley 52mm tb, Dynomax\Flowmaster catback. Coming Soon(?)- Fasttrack/Accell DFI
1989 Pontiac 20th Anniversary Turbo Trans Am - 161,000 miles, !cat, 9" K&N
#3
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There is NO difference in the 87 to 92 TPI bases only. The runners on the 89 and up TPI system driver side runner blocks the cold start injector passage on the manifold.
#4
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Car: Tree Huggers
Engine: Do Not
Transmission: Appreciate Me.
Just a reminder, there are some early '87 manifolds out there whose center bolt angle differs from the later ones (i.e. '85-E'87). Also for the cold start injector, I would personally plug it before you put the runners on.
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"The people always have some champion whom they set over them and nurse into greatness... This and no other is the root from which a tyrant springs; when he first appears he is a protector.
-Plato
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"The people always have some champion whom they set over them and nurse into greatness... This and no other is the root from which a tyrant springs; when he first appears he is a protector.
-Plato
#5
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A 9th injector? Hmmm, seems you learn something new every day. How exactly does it work and is it ratedthe same as the others??
Rob
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1987 IROC-Z Auto (LB9)
Black/grey with the stance of a streetfighter
Mods
Custom exhaust. 4 Inch pipe from the headders all the way back to a single muffler at the rear. No Cat.
Future mods:
K&Ns
RAM Air
New Underdrive pulleys-either March performance pulleys or Auto Specialties Performance
Air foil
Rob
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1987 IROC-Z Auto (LB9)
Black/grey with the stance of a streetfighter
Mods
Custom exhaust. 4 Inch pipe from the headders all the way back to a single muffler at the rear. No Cat.
Future mods:
K&Ns
RAM Air
New Underdrive pulleys-either March performance pulleys or Auto Specialties Performance
Air foil
#6
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The 9th injector (or cold start injector) is exactally that. It is used to richen the mixture at start up only!
Bob
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350 TPI, 700R4(rebuilt), K&N's, MSD 6AL, Headers, Flowmaster, 160* stat, airfoil, MAF screens cut out. 13.88 @ 101.18 mph
Bob
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350 TPI, 700R4(rebuilt), K&N's, MSD 6AL, Headers, Flowmaster, 160* stat, airfoil, MAF screens cut out. 13.88 @ 101.18 mph
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