Everything you wanted to know about modding your 305 TBI
Thread Starter
Joined: Feb 2001
Posts: 13,752
Likes: 560
From: Cincinnati, OH
Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Everything you wanted to know about modding your 305 TBI
I am slowly compiling a bunch of stuff to help the TBI novice out with their car. The folowing questions will help cover the basics and encourage them to search to find answers to their more specific questions. Feel free to add or cerrect to anything I have here. I typed this up really quick and with the help of 90RS305 we will eventually make it a TBI sticky to help declutter the top of the forum.
These questions and answers are in no particular order but will help you understand what your 305 TBI is capable with and what mods work best.
What are the specs on the 305TBI and how much power does it make?
The 305 TBI (LO3) came stock with 170hp and 255lb ft of torque. It has a 3.74” bore with a 3.48” stroke. It is a roller block with hydraulic roller cam and lifters.
Can a 305 be turned into a 350?
No. Although the blocks for the most part are the same externally they are not same internally. The 350 has a 4.00” bore and 3.48” stroke. The 350 can be bored .030”, .040” and sometimes .060”. The roller 305 can only be safely bored .030” because of the close proximity of the water jackets to the cylinder wall lining.
What other GM vehicles came with a TBI engine?
The TBI engine was used in pickup trucks in 5.0 and 5.7 liter versions. Most but not all were non roller blocks with similar power numbers to the LO3. Another TBI motor found in trucks was the 7.4 liter 454 TBI. This was a big block engine but its throttle body can be implemented onto your small block set-up. The TBI motor also came in a 350 version in Chevrolet Caprice Classics. This was the LO5 motor and was roller motor like the LO3 with around 205hp. TBI engines were used in a multitude of GM vehicles but the ones mentioned here closely resemble the LO3.
What should be the first thing I do to my 305 TBI?
The first thing you should do to your car is to make sure it has a full tune up and is in proper running condition. This means replacement of the spark plugs and wires along with a new distributor cap, and rotor. These cars tend to build up a lot of mileage over the years and are neglected from regular maintenance. The TBI unit should also be cleaned thoroughly. This requires taking it off and cleaning all of the small passages that run along the bottom side of it. Cleaning the PVC valve is also crucial. You will also want to check your serpentine belt and coolant hoses. They get old and crack and break down over time and this would be a good time to replace them. Finally, you will want to check your timing. The factory setting says to but it at 0* but most stock LO3’s like a bit more. This is a trial and error procedure and you will find that most LO3’s prefer anywhere from 4* to 8* advanced. Some like more and some like less and a little timing bump can increase fuel mileage, throttle response, and power. You may have to run a higher octane fuel though so you will have to consider that. After the car has received a full tune up you can start to consider your first modifications.
Now that it has a tune up where areas should I start to mod?
An extremely popular first mod is removing the stock air intake snorkel assembly and replacing it with an open air element or dual snorkel unit found on some earlier 3rd gens. A flat base air cleaner, called a non-drop base, is the best route to go here. This open element will sit flat on top of your TBI unit and allow you to remove the gold spacer ring that surrounds the perimeter of the top of your TBI unit. It will also clear your distributor. Another option is the drop base air cleaner. This unit does not sit flat and instead has a cone shape to it that engulfs the TBI unit and requires you to retain the gold spacer ring. This unit is not preferred because of distributor interference. This can be eliminated with the use of a TBI spacer that I will cover later.
Install guide 1
Install guide 2
What is a TBI spacer and does it add power?
A TBI spacer is just what it sounds like. It is a piece of plastic, wood, phonelic resin, or aluminum that bolts in between the TBI unit and intake manifold. It helps increase the intake manifold plenum size and is supposed to add power. It also acts as a thermal insulator between the TBI unit and intake manifold. Resin and plastic materials will be more effective than aluminum and will not conduct as much heat into the TBI unit. Whether they add power or not has yet to be dyno proven but I did not feel anything when I installed one on my car. The only purpose I bought one was to raise my drop based air cleaner off of my distributor. A TBI spacer usually requires a little tweaking of the throttle brackets and TV cables (for auto cars only) to keep it from pulling the throttle open. They are expensive and not worth the hassle for little to no power increase as well as a potentially difficult mod for a first time modder.
What is an injector spacer and do they add power?
An injector spacer works the same way a TBI spacer except that it lifts the injector pod up off the TBI unit. This helps un-shroud the TBI inlet bores and lets a little more air into the TBI unit.
How do I do the ultimate TBI mods and are they worth it?
There are two great tech articles on how to do this and they are pretty straight forward once you have a grinder and TBI unit in your hands. It is another trick to get every last CFM of air into the stock TBI. Flow tests have shown that a TBI unit with this modification that flow up to 5% more air. This added flow will help at higher RMP’s.
Ultimate TBI mods 1
Ultimate TBI mods 2
Thread with pics and good info
What aftermarket TBI units are out there and should I consider that as a first mod?
You really want to wait until you upgrade your TBI unit because the stock one can support every bolt on minus heads and cam. There are two commonly used 2 barrel units out there that people use. There is the Holley 670 TBI and there is the stock GM 454 TBI unit found on all 454 big block TBI trucks. Both have 2” bores as compared to the stock 1 11/16” bores. In addition to bore size both come with larger injectors that can support more power than the stock ones. These are not direct bolt on units and require some sensor modification as well as a manifold that has an inlet to support 2” bores.
What TBI intake manifolds are available for my car?
There are 3 aftermarket TBI intake manifolds that are out on the market today. Holley makes one that has 2” bores but requires you to use an older style EGR. GM performance parts make one that also has 2” bores but is designed to be used with vortec heads. They will not work with non vortec heads. The only real bolt-on without any modification is the Edelbrock Performer TBI intake. It is a direct bolt-on and all of your stock stuff can be transferred over to it without a hitch. Its only downfall is that it uses the stock size inlet bores that don’t allow you to use a larger TBI unit as previously mentioned. This problem can be remedied and the intake can be bored to accept 2” TBI units. The last option is to use an intake design to work with a carb and use a TBI adapter plate. Many people go this route and have a tremendous amount of success. TBI manifolds found on B-body cars are different all together. They have larger distributor holes so that the distributor can be removed without interfering with the cowl. To use one of these aftermarket intakes on a B-body would require some modification.
What is a good cam for my car?
There an endless amount of cams that can be used for your 305 but the most popular ones are the gm production LT1 cams out of f-bodies, corvettes, and b-bodies, and the L98 (350 TPI) cam. It is ok to go with a used roller cam and any of these cams can be found in the classified sections of multiple sites or on Ebay. They are offer purchased for under $50 and have great specs that are chip burning friendly. If you are going to retain your stock head than you need to keep a cam under .470” lift (you can go as high as .480” with proper measurement) to stay within the limits of the stock heads. You also want a cam with an LSA (lobe separation) between 111* and 115*. This type of duration is found on most fuel injection cams and is a must as far as tuning goes. Don’t forget, you need to use a hydraulic roller cam for all 88 thru 92 305 TBI’s.
LT1 cam info
What is chip burning and is it necessary?
You will find that the biggest gains on these cars will come from burning your own chips. The stock chip is very weak and can barely support the factory set-up. Anytime you mod your car you should look into burning a new chip to maximize its potential. You can get away with the stock chip with basic bolt-ons, but once you add a cam chip burning is a must. This will be stressed the most out of any of these mods. The sooner you learn what it takes to burn a new chip the better you will be able to make all of your new mods work in harmony. A heads and cam LO3 will run slower with the stock tune! A rule of thumb is to stay away from those off the shelf stage1 and stage 2 chips. They do not really do much and just add a bit of timing. Some of them can actually make your car run lean. If you just cannot burn your chips are on a strict budget but have to have a custom tune there is another option. You will see many people refereeing to data logging. What this is is a free software program that you install on a laptop computer and use a special connector to plug the laptop into your cars diagnostic (ALDL) port. Driving the car while this software is running will collect lots of data points. These points will tell you what you engine is doing at every rpm from timing to fuel. You can save this data and send it to a couple of different places that will burn you a chip based on the info you sent them. You can find this program from the following link.
Link to data log software
How much power can my stock fuel pump support?
The answer to this is not much. A stock pump can support a full exhaust, intake mods (manifold and air cleaner) and a very mild cam. One you have all of these mods and you go with a nice set of heads or decently sized cam the stock pump will not be able to deliver the necessary PSI at wide open engine load. A high flow unit will supply enough power to your TBI system no matter what mods you go with. Popular choices include, stock GM TPI pumps, Walbro 190lph and 255lph, and the Holley 255lph. Each of these pumps can support gobs of power but will work safely with your TBI set-up because your fuel pressure regulator will keep the fuel entering into your TBI unit where it needs to be.
What cylinder heads can I use on my car?
There are a few choices that you can go with. A popular set of heads are those found on 305 TPI cars. They have the same combustion chamber and valve size as your stock heads. There are two different castings look for. There are the 081 heads that are found on all 1987 and later 305 TPI cars and then there are the 416’s that are found on pre 1987 305 TPI and LG4 cars. The 081’s are a direct bolt on but the 416’s require some mods. You will have to convert the valvetrain to match the self aligning set-up on your stock heads and you will also have to use a pre 1986 intake manifold or modify the 4 center holes on your current intake. Another set is the World Products SR Torquer 305 heads. These heads have larger than stock valves, the same combustion chamber as stock, and provisions to accept cams up to .525” lift. These are only the basics to using any of these heads. The 081 and 416 heads are still lift limited and would need to be machined to accept higher lift cams. They can usually be found in junk yards for under $100 and can be real performers when ported. The SR’s can be found at Jeg’s or Summit and retail for around $700 a set.
What is a fuel pressure regulator, who makes them, and are they worth it?
A fuel pressure regulator does just as it sounds. It limits the amount of fuel that enters into your injector pod. There is no set value that came from the factory and some cars came with 12psi and others 15psi. Addition of mods may require you to adjust the fuel pressure a bit to allow more fuel in. If you have read the ultimate TBI mods tech articles you will see that you can make the stock one adjustable. There are also a few aftermarket units that you can buy. Jet makes a unit that can be adjusted for a constant pressure over every RPM point. If you want one that varies with RPM you will need to look into the GM vacuum adjustable regulator. This regulator changes based on a vacuum source and will rise as RPM does. It is still adjustable so that you can tune down the pressure at idle to avoid running rich, yet have enough pressure at wide open throttle to avoid going lean. It is a neat unit and seems to work fairly well with the stock chip. All other fuel pressure changes need to be programmed into the chip. Some people can get away with the stock chip when they go with a mild cam because they adjust their fuel pressure and bump the timing up a bit.
These questions and answers are in no particular order but will help you understand what your 305 TBI is capable with and what mods work best.
What are the specs on the 305TBI and how much power does it make?
The 305 TBI (LO3) came stock with 170hp and 255lb ft of torque. It has a 3.74” bore with a 3.48” stroke. It is a roller block with hydraulic roller cam and lifters.
Can a 305 be turned into a 350?
No. Although the blocks for the most part are the same externally they are not same internally. The 350 has a 4.00” bore and 3.48” stroke. The 350 can be bored .030”, .040” and sometimes .060”. The roller 305 can only be safely bored .030” because of the close proximity of the water jackets to the cylinder wall lining.
What other GM vehicles came with a TBI engine?
The TBI engine was used in pickup trucks in 5.0 and 5.7 liter versions. Most but not all were non roller blocks with similar power numbers to the LO3. Another TBI motor found in trucks was the 7.4 liter 454 TBI. This was a big block engine but its throttle body can be implemented onto your small block set-up. The TBI motor also came in a 350 version in Chevrolet Caprice Classics. This was the LO5 motor and was roller motor like the LO3 with around 205hp. TBI engines were used in a multitude of GM vehicles but the ones mentioned here closely resemble the LO3.
What should be the first thing I do to my 305 TBI?
The first thing you should do to your car is to make sure it has a full tune up and is in proper running condition. This means replacement of the spark plugs and wires along with a new distributor cap, and rotor. These cars tend to build up a lot of mileage over the years and are neglected from regular maintenance. The TBI unit should also be cleaned thoroughly. This requires taking it off and cleaning all of the small passages that run along the bottom side of it. Cleaning the PVC valve is also crucial. You will also want to check your serpentine belt and coolant hoses. They get old and crack and break down over time and this would be a good time to replace them. Finally, you will want to check your timing. The factory setting says to but it at 0* but most stock LO3’s like a bit more. This is a trial and error procedure and you will find that most LO3’s prefer anywhere from 4* to 8* advanced. Some like more and some like less and a little timing bump can increase fuel mileage, throttle response, and power. You may have to run a higher octane fuel though so you will have to consider that. After the car has received a full tune up you can start to consider your first modifications.
Now that it has a tune up where areas should I start to mod?
An extremely popular first mod is removing the stock air intake snorkel assembly and replacing it with an open air element or dual snorkel unit found on some earlier 3rd gens. A flat base air cleaner, called a non-drop base, is the best route to go here. This open element will sit flat on top of your TBI unit and allow you to remove the gold spacer ring that surrounds the perimeter of the top of your TBI unit. It will also clear your distributor. Another option is the drop base air cleaner. This unit does not sit flat and instead has a cone shape to it that engulfs the TBI unit and requires you to retain the gold spacer ring. This unit is not preferred because of distributor interference. This can be eliminated with the use of a TBI spacer that I will cover later.
Install guide 1
Install guide 2
What is a TBI spacer and does it add power?
A TBI spacer is just what it sounds like. It is a piece of plastic, wood, phonelic resin, or aluminum that bolts in between the TBI unit and intake manifold. It helps increase the intake manifold plenum size and is supposed to add power. It also acts as a thermal insulator between the TBI unit and intake manifold. Resin and plastic materials will be more effective than aluminum and will not conduct as much heat into the TBI unit. Whether they add power or not has yet to be dyno proven but I did not feel anything when I installed one on my car. The only purpose I bought one was to raise my drop based air cleaner off of my distributor. A TBI spacer usually requires a little tweaking of the throttle brackets and TV cables (for auto cars only) to keep it from pulling the throttle open. They are expensive and not worth the hassle for little to no power increase as well as a potentially difficult mod for a first time modder.
What is an injector spacer and do they add power?
An injector spacer works the same way a TBI spacer except that it lifts the injector pod up off the TBI unit. This helps un-shroud the TBI inlet bores and lets a little more air into the TBI unit.
How do I do the ultimate TBI mods and are they worth it?
There are two great tech articles on how to do this and they are pretty straight forward once you have a grinder and TBI unit in your hands. It is another trick to get every last CFM of air into the stock TBI. Flow tests have shown that a TBI unit with this modification that flow up to 5% more air. This added flow will help at higher RMP’s.
Ultimate TBI mods 1
Ultimate TBI mods 2
Thread with pics and good info
What aftermarket TBI units are out there and should I consider that as a first mod?
You really want to wait until you upgrade your TBI unit because the stock one can support every bolt on minus heads and cam. There are two commonly used 2 barrel units out there that people use. There is the Holley 670 TBI and there is the stock GM 454 TBI unit found on all 454 big block TBI trucks. Both have 2” bores as compared to the stock 1 11/16” bores. In addition to bore size both come with larger injectors that can support more power than the stock ones. These are not direct bolt on units and require some sensor modification as well as a manifold that has an inlet to support 2” bores.
What TBI intake manifolds are available for my car?
There are 3 aftermarket TBI intake manifolds that are out on the market today. Holley makes one that has 2” bores but requires you to use an older style EGR. GM performance parts make one that also has 2” bores but is designed to be used with vortec heads. They will not work with non vortec heads. The only real bolt-on without any modification is the Edelbrock Performer TBI intake. It is a direct bolt-on and all of your stock stuff can be transferred over to it without a hitch. Its only downfall is that it uses the stock size inlet bores that don’t allow you to use a larger TBI unit as previously mentioned. This problem can be remedied and the intake can be bored to accept 2” TBI units. The last option is to use an intake design to work with a carb and use a TBI adapter plate. Many people go this route and have a tremendous amount of success. TBI manifolds found on B-body cars are different all together. They have larger distributor holes so that the distributor can be removed without interfering with the cowl. To use one of these aftermarket intakes on a B-body would require some modification.
What is a good cam for my car?
There an endless amount of cams that can be used for your 305 but the most popular ones are the gm production LT1 cams out of f-bodies, corvettes, and b-bodies, and the L98 (350 TPI) cam. It is ok to go with a used roller cam and any of these cams can be found in the classified sections of multiple sites or on Ebay. They are offer purchased for under $50 and have great specs that are chip burning friendly. If you are going to retain your stock head than you need to keep a cam under .470” lift (you can go as high as .480” with proper measurement) to stay within the limits of the stock heads. You also want a cam with an LSA (lobe separation) between 111* and 115*. This type of duration is found on most fuel injection cams and is a must as far as tuning goes. Don’t forget, you need to use a hydraulic roller cam for all 88 thru 92 305 TBI’s.
LT1 cam info
What is chip burning and is it necessary?
You will find that the biggest gains on these cars will come from burning your own chips. The stock chip is very weak and can barely support the factory set-up. Anytime you mod your car you should look into burning a new chip to maximize its potential. You can get away with the stock chip with basic bolt-ons, but once you add a cam chip burning is a must. This will be stressed the most out of any of these mods. The sooner you learn what it takes to burn a new chip the better you will be able to make all of your new mods work in harmony. A heads and cam LO3 will run slower with the stock tune! A rule of thumb is to stay away from those off the shelf stage1 and stage 2 chips. They do not really do much and just add a bit of timing. Some of them can actually make your car run lean. If you just cannot burn your chips are on a strict budget but have to have a custom tune there is another option. You will see many people refereeing to data logging. What this is is a free software program that you install on a laptop computer and use a special connector to plug the laptop into your cars diagnostic (ALDL) port. Driving the car while this software is running will collect lots of data points. These points will tell you what you engine is doing at every rpm from timing to fuel. You can save this data and send it to a couple of different places that will burn you a chip based on the info you sent them. You can find this program from the following link.
Link to data log software
How much power can my stock fuel pump support?
The answer to this is not much. A stock pump can support a full exhaust, intake mods (manifold and air cleaner) and a very mild cam. One you have all of these mods and you go with a nice set of heads or decently sized cam the stock pump will not be able to deliver the necessary PSI at wide open engine load. A high flow unit will supply enough power to your TBI system no matter what mods you go with. Popular choices include, stock GM TPI pumps, Walbro 190lph and 255lph, and the Holley 255lph. Each of these pumps can support gobs of power but will work safely with your TBI set-up because your fuel pressure regulator will keep the fuel entering into your TBI unit where it needs to be.
What cylinder heads can I use on my car?
There are a few choices that you can go with. A popular set of heads are those found on 305 TPI cars. They have the same combustion chamber and valve size as your stock heads. There are two different castings look for. There are the 081 heads that are found on all 1987 and later 305 TPI cars and then there are the 416’s that are found on pre 1987 305 TPI and LG4 cars. The 081’s are a direct bolt on but the 416’s require some mods. You will have to convert the valvetrain to match the self aligning set-up on your stock heads and you will also have to use a pre 1986 intake manifold or modify the 4 center holes on your current intake. Another set is the World Products SR Torquer 305 heads. These heads have larger than stock valves, the same combustion chamber as stock, and provisions to accept cams up to .525” lift. These are only the basics to using any of these heads. The 081 and 416 heads are still lift limited and would need to be machined to accept higher lift cams. They can usually be found in junk yards for under $100 and can be real performers when ported. The SR’s can be found at Jeg’s or Summit and retail for around $700 a set.
What is a fuel pressure regulator, who makes them, and are they worth it?
A fuel pressure regulator does just as it sounds. It limits the amount of fuel that enters into your injector pod. There is no set value that came from the factory and some cars came with 12psi and others 15psi. Addition of mods may require you to adjust the fuel pressure a bit to allow more fuel in. If you have read the ultimate TBI mods tech articles you will see that you can make the stock one adjustable. There are also a few aftermarket units that you can buy. Jet makes a unit that can be adjusted for a constant pressure over every RPM point. If you want one that varies with RPM you will need to look into the GM vacuum adjustable regulator. This regulator changes based on a vacuum source and will rise as RPM does. It is still adjustable so that you can tune down the pressure at idle to avoid running rich, yet have enough pressure at wide open throttle to avoid going lean. It is a neat unit and seems to work fairly well with the stock chip. All other fuel pressure changes need to be programmed into the chip. Some people can get away with the stock chip when they go with a mild cam because they adjust their fuel pressure and bump the timing up a bit.
Last edited by ShiftyCapone; Oct 5, 2005 at 10:23 PM.
Supreme Member
Joined: Apr 2003
Posts: 2,070
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From: Tempe, Arizona
Car: 96 Silverado/99 Suburban
Engine: 700 cubic inches of 'Muican Awesome
Transmission: 4L80/4L60
Axle/Gears: Chunky/Clunky
Re: Everything you wanted to know about modding your 305 TBI
Originally posted by ShiftyCapone
What other GM vehicles came with a TBI engine?
The TBI engine was used in pickup trucks in 5.0 and 5.7 liter versions. Most but not all were non roller blocks with similar power numbers to the LO3. The TBI motor also came in a 350 version in Chevrolet Caprice Classics. This was the LO5 motor and was roller motor like the LO3 with around 205hp.[/B]
What other GM vehicles came with a TBI engine?
The TBI engine was used in pickup trucks in 5.0 and 5.7 liter versions. Most but not all were non roller blocks with similar power numbers to the LO3. The TBI motor also came in a 350 version in Chevrolet Caprice Classics. This was the LO5 motor and was roller motor like the LO3 with around 205hp.[/B]
This is looking really good Shifty! Can't wait to see what this starts to amount to!
Bruce (90RS305)
Thread Starter
Joined: Feb 2001
Posts: 13,752
Likes: 560
From: Cincinnati, OH
Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Re: Re: Everything you wanted to know about modding your 305 TBI
Originally posted by 90RS305
Don't forget about the 454 TBI. I don't know the exact specs on it but the 454 unit is a rather popular TB for people looking to get better air flow...
Don't forget about the 454 TBI. I don't know the exact specs on it but the 454 unit is a rather popular TB for people looking to get better air flow...
Junior Member
Joined: Mar 2004
Posts: 14
Likes: 0
From: Crystal Lake, Illinois 60014
Car: 1983 T/A T-Tops
Engine: A 305 Crossfire (soon 400ci?)
Transmission: 700R4
so what are my options
I have an 83 with a crossfire intake, so what are my options? It's my first third gen so I am lost. Should I just switch out my intake and such or can I do any thing with what i have? It is a super torqey (is that a word?) set up. I already did a tune up two K&N filters (power buldges kick ***) MSD 6A ignition/ coil. And I'm working on an exhaust system just trying to figure out what I want. Also a 3.73 posi rear. So what are my options with the tuning and upgrades for the crossfire? What cam works well with it etc. I just want to go FAST!! Oh yeah I'm also working on a 400...I'll tel ya more later.
Thread Starter
Joined: Feb 2001
Posts: 13,752
Likes: 560
From: Cincinnati, OH
Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Re: so what are my options
Originally posted by indytrucks
I have an 83 with a crossfire intake, so what are my options? It's my first third gen so I am lost. Should I just switch out my intake and such or can I do any thing with what i have? It is a super torqey (is that a word?) set up. I already did a tune up two K&N filters (power buldges kick ***) MSD 6A ignition/ coil. And I'm working on an exhaust system just trying to figure out what I want. Also a 3.73 posi rear. So what are my options with the tuning and upgrades for the crossfire? What cam works well with it etc. I just want to go FAST!! Oh yeah I'm also working on a 400...I'll tel ya more later.
I have an 83 with a crossfire intake, so what are my options? It's my first third gen so I am lost. Should I just switch out my intake and such or can I do any thing with what i have? It is a super torqey (is that a word?) set up. I already did a tune up two K&N filters (power buldges kick ***) MSD 6A ignition/ coil. And I'm working on an exhaust system just trying to figure out what I want. Also a 3.73 posi rear. So what are my options with the tuning and upgrades for the crossfire? What cam works well with it etc. I just want to go FAST!! Oh yeah I'm also working on a 400...I'll tel ya more later.
or something along those lines. There are some really fast cars on this site running a cross fire set-up.
Supreme Member
Joined: Sep 2002
Posts: 9,192
Likes: 19
From: Cary, North Carolina
Car: 1992 RS
Engine: Carbed 350
Transmission: 700R4
Axle/Gears: 3.42 posi
You might want to mention that intakes depend on a head decision. For instance, if you use (or plan to use soon) the older 416 heads, you'll want to not do an intake swap until that decision is made. If older heads are used (ie 416's), then a whole new realm of intake options exist (carb intakes), and usually at lower prices (ie my Weiand 8000 was only $125). In addition then I guess, with carb intakes options you'll have to get into the TBI adapter discussion as well, as such is required for the carb intakes. LOL As the song says, "one thing leads to another"!
Junior Member
Joined: Mar 2004
Posts: 27
Likes: 0
From: Connecticutt
Car: 87 Iroc
Engine: 350 TPI
Transmission: 700R4
Help!!
Hi, I am new to posting!! I stop by this site everyday to see what is new and exciting. This article helped me out a bit...I am looking to buy a third gen camaro. I have had an 86 305 tpi and and 88 305 tpi...I am now considering an 86 305 tbi.....I guess what I am asking is will I be disappointed in the performance of a TBI...seeing that all I have driven is TPI's.
What is the one thing you guys recommend that I do to a TBI motor to gain that performance???
Thanks for reading....sorry that I am a novice when it comes to this stuff...but I am willing to learn.
Thanks again, Kim
What is the one thing you guys recommend that I do to a TBI motor to gain that performance???
Thanks for reading....sorry that I am a novice when it comes to this stuff...but I am willing to learn.
Thanks again, Kim
Trending Topics
Thread Starter
Joined: Feb 2001
Posts: 13,752
Likes: 560
From: Cincinnati, OH
Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Re: Help!!
Originally posted by 2chey
Hi, I am new to posting!! I stop by this site everyday to see what is new and exciting. This article helped me out a bit...I am looking to buy a third gen camaro. I have had an 86 305 tpi and and 88 305 tpi...I am now considering an 86 305 tbi.....I guess what I am asking is will I be disappointed in the performance of a TBI...seeing that all I have driven is TPI's.
What is the one thing you guys recommend that I do to a TBI motor to gain that performance???
Thanks for reading....sorry that I am a novice when it comes to this stuff...but I am willing to learn.
Thanks again, Kim
Hi, I am new to posting!! I stop by this site everyday to see what is new and exciting. This article helped me out a bit...I am looking to buy a third gen camaro. I have had an 86 305 tpi and and 88 305 tpi...I am now considering an 86 305 tbi.....I guess what I am asking is will I be disappointed in the performance of a TBI...seeing that all I have driven is TPI's.
What is the one thing you guys recommend that I do to a TBI motor to gain that performance???
Thanks for reading....sorry that I am a novice when it comes to this stuff...but I am willing to learn.
Thanks again, Kim
Junior Member
Joined: Aug 2004
Posts: 6
Likes: 0
From: PA
Car: 84 Z-28
Engine: 355 750 double pumper
Transmission: TCI Turbo 350
Axle/Gears: 4.10 spool
Hi I have a Holley TBI and I was wondering how you change the idel .I did it the way you would a carb but the computer changes it back to 500, and thats no good any help would be great thanks
Thread Starter
Joined: Feb 2001
Posts: 13,752
Likes: 560
From: Cincinnati, OH
Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Originally posted by gregxx
Hi I have a Holley TBI and I was wondering how you change the idel .I did it the way you would a carb but the computer changes it back to 500, and thats no good any help would be great thanks
Hi I have a Holley TBI and I was wondering how you change the idel .I did it the way you would a carb but the computer changes it back to 500, and thats no good any help would be great thanks
Junior Member
Joined: Aug 2004
Posts: 6
Likes: 0
From: PA
Car: 84 Z-28
Engine: 355 750 double pumper
Transmission: TCI Turbo 350
Axle/Gears: 4.10 spool
I just have the basics headers msd ing., 3" pipe,3" cow hood,and the other stuff listed,but i have a powerfull stero and if im at a stop light i loose some electricty,not enugh to stall the car but i do loose some and i thought turning the idel up to at least 800 might help(i do have a cap. on the amps also)
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