hey Z28inNC i own a 1986 chevy 1/2 ton and my 305 LG4 is not a poor motor myn kicks ass but of course i beefed it up with a holly contender intake witha built up quadrajet and im only 14
I beat alot of cars in my 88 TA w/305 tpi:) They r actually pretty hauss motors. I also have a shift kit, chip, and flowmasters. All of which help greatly. However, my buddy has a 87RS Camero with a 305TBI and that thing is a damn dog:( I noticed a huge difference between TBI and TPI 4 sure. His RS wont even spin the damn tires and is slow as molasses. Im sure a better carb and some tuning would help but those carbs stock r waaaaaayyyyy slow Lol. My GF 3.1 v6 achieva would run circles round it:)
TPI's create great low end torque, below 4,000 rpms, but above that the motor gets no air, the only way to fix that is installing a ram air of some sort
@xxxXW4NT3DXxxx The TPIs actually run VERY well on a stock 305, up to 5,500 rpm or more. When you open up the rest of the engine, the 305 responds well to intake runner upgrades. A set of 059 L30 305 Vortec heads, an Edelbrock 3817 TPI Vortec intake, TPIS oversize runners along with a nice roller cam,Tri-Y headers and a full exhaust will wake that 305 up like no other. I ran a 14.8 @ 93 in a 5,500 lbs Fullsize van with a TPI 305.
Here's a question for you guys. I have a all original 1985 IROC with the 305 TPI (266,000+ miles) and the engine is tired. I want to rebuild the motor, maybe pump it up from 305 to UM..343? w/ street pistons,new cam,new everything. Basically, I want to make my 'roc like showroom new (numbers matching block/original) but with more horses. Any thoughts?
@CheckYourSelf24Here 305's are VERY under rated. You can make a 305 come to life just like any other SBC. There are numerous builds if you search google and thirdgen.org. If you dont have a problem keeping the 305, build it. 12's arent bad at all.
@MrRobGT Depends on the motor. The TPI 305 is a solid motor, but some305's are crap.Both the LG4(the one with the quadrajunk) and LO3(TBI) where pretty poor motors. I've owned Camaros both(87LT and 92RS), and both where dissapointing.
Is this the motor with the swirl port heads on it?
Do you think the TPI or TBI makes more tq at the hit of the throttle, or in other words which system makes more power under 2000rpm? Acceleration in high gear is the tale tell.
im pretty sure the TPI has alot more low end tq (i have an 87 z28 with a fresh 305 TPI in her, and my car hauls in comparison to my friend's 91 RS which also has a 305, but his is the TBI)
@cohan320 U r corect TPI stock waaaayyy outperforms TBI when it comes 2 the 305. Mods may be a different story but my buddy also has an RS with a 305TBI and my bird with a 305TPI wipes the floor with his Camero big time
Do you have the A/C hooked up on that? I'm tempted to put a modded TPI (bigger runners, etc) on my 385 stroker. I'm currently running a Sanden 709 (the original A6 was long gone when I got my van) on my '78 G10 Shorty.
A/C is hooked up and functions front and rear. I used a newer style replacement condenser and had R-134a barrier style hoses made to connect everything including the rear evaporator. I also replaced the original accessory brackets and accessories with a setup from a 1992 G20. I used a new alternator and a/c compressor. Charged with R12, I blow 42*F on high blow both front and rear. With the insulation in my van you could hang meat after 15-20 minutes, even in the hottest weather.
I guess I should also mention that I have an electric fan assembly from a Nissan Altima that had great fit with the stock radiator and pulls a ton of air.
I wired 4 TPI injector in parallel to one of the TBI wires and then repeated on the other side. I performed the MPI Memcal Jumper Modification. I also replaced two of the injector driver resistors out of the PCM and replaced them with a jumper wire. Peak and Hold to Saturated
I have a 4L80E transmission now, running $OE.
TPI definately has more torque in the mid-range, but falls off heavily, where the TBI motored on. Low-end torque is identical between the two.
I noticed you are running the '7427 ECM for your TPI. How did you hook up the multi-port to it? Are you using the $OD code? Do you have a 4L60E trans? How tough was it to set it all up electronics wise? Nice van. Should have come factory with TPI on them, likewise with trucks and suburbans
do you have any tips on getting the bird cage on and off quickly? because mine is a pain in the ass to take off and put back on.
trucker765 8 months ago
hey Z28inNC i own a 1986 chevy 1/2 ton and my 305 LG4 is not a poor motor myn kicks ass but of course i beefed it up with a holly contender intake witha built up quadrajet and im only 14
Mr305smallblock 1 year ago
I beat alot of cars in my 88 TA w/305 tpi:) They r actually pretty hauss motors. I also have a shift kit, chip, and flowmasters. All of which help greatly. However, my buddy has a 87RS Camero with a 305TBI and that thing is a damn dog:( I noticed a huge difference between TBI and TPI 4 sure. His RS wont even spin the damn tires and is slow as molasses. Im sure a better carb and some tuning would help but those carbs stock r waaaaaayyyyy slow Lol. My GF 3.1 v6 achieva would run circles round it:)
lamiac2411 1 year ago
TPI's create great low end torque, below 4,000 rpms, but above that the motor gets no air, the only way to fix that is installing a ram air of some sort
xxxXW4NT3DXxxx 1 year ago
@xxxXW4NT3DXxxx The TPIs actually run VERY well on a stock 305, up to 5,500 rpm or more. When you open up the rest of the engine, the 305 responds well to intake runner upgrades. A set of 059 L30 305 Vortec heads, an Edelbrock 3817 TPI Vortec intake, TPIS oversize runners along with a nice roller cam,Tri-Y headers and a full exhaust will wake that 305 up like no other. I ran a 14.8 @ 93 in a 5,500 lbs Fullsize van with a TPI 305.
Fast355 1 year ago 2
@Fast355 Holy shit man, that's fast for a solid brick, lol.
brapboys503 10 months ago
Here's a question for you guys. I have a all original 1985 IROC with the 305 TPI (266,000+ miles) and the engine is tired. I want to rebuild the motor, maybe pump it up from 305 to UM..343? w/ street pistons,new cam,new everything. Basically, I want to make my 'roc like showroom new (numbers matching block/original) but with more horses. Any thoughts?
CheckYourSelf24Here 1 year ago
@CheckYourSelf24Here 305's are VERY under rated. You can make a 305 come to life just like any other SBC. There are numerous builds if you search google and thirdgen.org. If you dont have a problem keeping the 305, build it. 12's arent bad at all.
MrRobGT 1 year ago
@MrRobGT Depends on the motor. The TPI 305 is a solid motor, but some305's are crap.Both the LG4(the one with the quadrajunk) and LO3(TBI) where pretty poor motors. I've owned Camaros both(87LT and 92RS), and both where dissapointing.
They dont call'em 5.slows for nuthin.
Z28inNC 1 year ago
305? LOL!
claviz13 2 years ago
That sounds good !
photographermatt 2 years ago
kinds sounds like my dad's 1998 1500 with the Vortec 305
ZackMcLeish13 2 years ago
I see at the bottom of the page you say TPI & TBI are the same at low rpm, do you have a theory on this?
strokerengine 3 years ago
Is this the motor with the swirl port heads on it?
Do you think the TPI or TBI makes more tq at the hit of the throttle, or in other words which system makes more power under 2000rpm? Acceleration in high gear is the tale tell.
strokerengine 3 years ago
im pretty sure the TPI has alot more low end tq (i have an 87 z28 with a fresh 305 TPI in her, and my car hauls in comparison to my friend's 91 RS which also has a 305, but his is the TBI)
cohan320 3 years ago
@cohan320 U r corect TPI stock waaaayyy outperforms TBI when it comes 2 the 305. Mods may be a different story but my buddy also has an RS with a 305TBI and my bird with a 305TPI wipes the floor with his Camero big time
lamiac2411 1 year ago
Do you have the A/C hooked up on that? I'm tempted to put a modded TPI (bigger runners, etc) on my 385 stroker. I'm currently running a Sanden 709 (the original A6 was long gone when I got my van) on my '78 G10 Shorty.
dburrigh 3 years ago
A/C is hooked up and functions front and rear. I used a newer style replacement condenser and had R-134a barrier style hoses made to connect everything including the rear evaporator. I also replaced the original accessory brackets and accessories with a setup from a 1992 G20. I used a new alternator and a/c compressor. Charged with R12, I blow 42*F on high blow both front and rear. With the insulation in my van you could hang meat after 15-20 minutes, even in the hottest weather.
Fast355 3 years ago
I guess I should also mention that I have an electric fan assembly from a Nissan Altima that had great fit with the stock radiator and pulls a ton of air.
Fast355 3 years ago
thats bad ass man i got the same motor in my 86 iroc
fireman01723 3 years ago
hey by any chance would it be somewhat dangerous to drive around without the thing to cover up the engine or what would be some problems?
litllenike 3 years ago
If something were to break it would probably shoot metal parts out. Maybe a chunk of block or a piston.
CamaroTBI 3 years ago
well thts always gd
litllenike 3 years ago
definately
CamaroTBI 3 years ago
I wired 4 TPI injector in parallel to one of the TBI wires and then repeated on the other side. I performed the MPI Memcal Jumper Modification. I also replaced two of the injector driver resistors out of the PCM and replaced them with a jumper wire. Peak and Hold to Saturated
I have a 4L80E transmission now, running $OE.
TPI definately has more torque in the mid-range, but falls off heavily, where the TBI motored on. Low-end torque is identical between the two.
Fast355 3 years ago
I noticed you are running the '7427 ECM for your TPI. How did you hook up the multi-port to it? Are you using the $OD code? Do you have a 4L60E trans? How tough was it to set it all up electronics wise? Nice van. Should have come factory with TPI on them, likewise with trucks and suburbans
chevy385 3 years ago
DAMN! That's sweet!
jigsaw1984 4 years ago
one bad ass motherfucker man awesome i want to get an 82' chevy van also
Peterbilt379driver 4 years ago