TBI spacer?
08-20-2002, 11:31 AM
#3
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Car: Formula
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The spacer that Jegs sells is 1" thick and for the GM Trucks. If you use it you will have to modify the throtle cables and\or brackets. Turbo City sells them I believe in 1\4" and 1\2" that will not require modifications. I have seen some on ebay also, but most of them are plastic or composite.
08-20-2002, 05:43 PM
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Car: Formula
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Go to their website www.turbocity.com, they do sell them. Also try http://www.cfm-tech.com or http://www.martelbros.com/cgi-bin/st...jet/2002-2.htm, but I don't know how good they are.
08-20-2002, 07:56 PM
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ok...that jegs 1" one...i used it. all u gotta do is switch the throttle cable and cruise control cables on the throttle bracket. when doing this though the cruise opening has a little triangular shaped thing sticking out which can be filed down and the cables will just swap right over. well at least they did on mine. is this with stock intake/stock hood?
08-20-2002, 09:16 PM
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I am interested in installing a spacer under the TBI on my 91 RS LO3 (I think I'll make it though). I have a couple questions, though...
If I make a spacer the same thickness as the spacer ring that lifts up the air cleaner, can I remove the ring? Will the stock aircleaner base (snorkel etc.) clear the TBI assembly itself? I'm wondering/thinking that the spacer is so the base will clear other items on the manifold besides the TBI unit--is that right?
I picked up a truck type aircleaner lid and liked the boost (I'll add the other snorkel later) but I noticed that the higher lid left an impression on the felt insulation in the engine compartment. I want to keep the stock hood, so it looks like I am getting close to the maximum I can lift the whole assembly.
Thanks for any thoughts/advice!
Kevin
If I make a spacer the same thickness as the spacer ring that lifts up the air cleaner, can I remove the ring? Will the stock aircleaner base (snorkel etc.) clear the TBI assembly itself? I'm wondering/thinking that the spacer is so the base will clear other items on the manifold besides the TBI unit--is that right?
I picked up a truck type aircleaner lid and liked the boost (I'll add the other snorkel later) but I noticed that the higher lid left an impression on the felt insulation in the engine compartment. I want to keep the stock hood, so it looks like I am getting close to the maximum I can lift the whole assembly.
Thanks for any thoughts/advice!
Kevin
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08-21-2002, 12:00 AM
#8
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Originally posted by CamaroGuy71
ok...that jegs 1" one...i used it. all u gotta do is switch the throttle cable and cruise control cables on the throttle bracket. when doing this though the cruise opening has a little triangular shaped thing sticking out which can be filed down and the cables will just swap right over. well at least they did on mine. is this with stock intake/stock hood?
ok...that jegs 1" one...i used it. all u gotta do is switch the throttle cable and cruise control cables on the throttle bracket. when doing this though the cruise opening has a little triangular shaped thing sticking out which can be filed down and the cables will just swap right over. well at least they did on mine. is this with stock intake/stock hood?
08-21-2002, 02:48 PM
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Car: 91 Z28
Engine: 305 TPI
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The jegs spacer is about 74$. Comes with hardware(longer mounting bolts, gaskets)www.jegs.com Part#15400
Last edited by 305iroc; 08-21-2002 at 03:15 PM.
08-21-2002, 03:56 PM
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I picked up a dense commercial grade polyethylene cutting board at Lowe's 7/16" X 15" X 12". Cost: $7.92 Probably enough material there for about 8 TBI to manifold spacers. I'll have to measure the bolts later but I have got a fairly large 20 year collection of metric and standard bolts -- hopefully they'll be in there.
I guess no-one has ever checked out my question about removing the spacer ring and balancing that with a commensurate lift of the the TBI unit, so I'll do that.
Here's something interesting... I had been getting an intermittant code 32 (EGR system) virtually every time that I took the car out for an extended ride (10 miles +). Yesterday my wife and I swapped the truck air cleaner lid (actually out of an old full size GM car) for the stock lid (amazingly, there was a brand new Fram filter sitting there in the yard too -- $2 for both parts). The yard is about 30 miles from the house and *surprise* no more code 32 flashing of the service engine light. Nice! We drove the car about 50 miles today and still no light! I'll cross my fingers. Not sure why that made a difference but apparently it did.
Kevin
I guess no-one has ever checked out my question about removing the spacer ring and balancing that with a commensurate lift of the the TBI unit, so I'll do that.
Here's something interesting... I had been getting an intermittant code 32 (EGR system) virtually every time that I took the car out for an extended ride (10 miles +). Yesterday my wife and I swapped the truck air cleaner lid (actually out of an old full size GM car) for the stock lid (amazingly, there was a brand new Fram filter sitting there in the yard too -- $2 for both parts). The yard is about 30 miles from the house and *surprise* no more code 32 flashing of the service engine light. Nice! We drove the car about 50 miles today and still no light! I'll cross my fingers. Not sure why that made a difference but apparently it did.
Kevin
08-22-2002, 12:56 AM
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I pulled the TBI and checked the clearances with the stock "drop" filter assembly. As long as I use right angle vacuum connectors on the sensor connections beneath, I can dispense with the spacer ring.
The spacer ring is 14/16" so by doubling two of the high density 7/16" polyethylene spacers I am right on target. I'll do the mods in the TBI article and end up with a 14/16" spacer complete with the high clearance air filter that will clear the stock hood and look stock too. I'll add the second snorkel later.
I am going to lift the throttle cable bracket using solid spacers, a longer bolt, and stud. Swapping the cables' positions sounds neat but I have had some negative experiences when deviating too much from the factory angles on other cars. Using a stud to replace and raise the angled manifold bolt attachment point on the rear of the bracket will pivot the bracket slightly around the longitudinal axis of the forward bolt but will keep the relative horizontal link dimensions the same for the three cables. I found a nice wide solid steel spacer for the forward bolt that is exactly 14/16" high. Nice!
I routed the hard gas lines over the hard vacuum line for the brake booster (they formerly ran underneath it). I will put a section of split hose on the vacuum line where they touch. I don't want them to rub against each other and eventually start a fire.
Kevin
The spacer ring is 14/16" so by doubling two of the high density 7/16" polyethylene spacers I am right on target. I'll do the mods in the TBI article and end up with a 14/16" spacer complete with the high clearance air filter that will clear the stock hood and look stock too. I'll add the second snorkel later.
I am going to lift the throttle cable bracket using solid spacers, a longer bolt, and stud. Swapping the cables' positions sounds neat but I have had some negative experiences when deviating too much from the factory angles on other cars. Using a stud to replace and raise the angled manifold bolt attachment point on the rear of the bracket will pivot the bracket slightly around the longitudinal axis of the forward bolt but will keep the relative horizontal link dimensions the same for the three cables. I found a nice wide solid steel spacer for the forward bolt that is exactly 14/16" high. Nice!
I routed the hard gas lines over the hard vacuum line for the brake booster (they formerly ran underneath it). I will put a section of split hose on the vacuum line where they touch. I don't want them to rub against each other and eventually start a fire.
Kevin
08-22-2002, 01:07 AM
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Car: 91 Z28
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Transmission: 5 speed
Axle/Gears: 3.42's
Sounds good Kevin. Thanks for the tips. I'll be useing them soon. To think I almost spent 74 bucks on a tbi spacer. Thanks agin.
Brian
Brian
08-22-2002, 01:28 AM
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Well, I will try to get this done tomorrow and let you know how it went. I am hoping the linkage will go smoothly (cross my fingers). Seems like if there is going to be clearance problems, that's where they'll show up. Previous owner of the car was nice enough to have bought a TBI rebuild kit with all the gaskets and never installed it. [Tomco Inc. fuel system kit, 5526 D]
08-22-2002, 01:54 AM
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Maybe this thread will help with your fabbing. Goto the last post.
https://www.thirdgen.org/techbb2/sho...ht=TBI+adapter
https://www.thirdgen.org/techbb2/sho...ht=TBI+adapter
08-23-2002, 12:54 AM
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Well, I've got the spacer installed. Of course, the cables were the big headache. I am going to have to modify the bracket so that I have more adjustment available (moving the bracket forward towards the TBI.
Right now I have the cruise control disconnected because that was binding. The transmission cable needs to be adjusted as the tranny is not downshifting properly when I give it full throttle. But it is running!
Right now I have the cruise control disconnected because that was binding. The transmission cable needs to be adjusted as the tranny is not downshifting properly when I give it full throttle. But it is running!
08-23-2002, 01:01 AM
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Car: 91 Z28
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Good to here its working out Kevin. I don't have cruise control so that wouldn't be a problem. Did you notice a diffrence in performance? Thanks for the update.
Last edited by 305iroc; 08-23-2002 at 01:04 AM.
08-23-2002, 01:17 AM
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I took it out for a spin at about 1:30AM and that is when I noticed it wouldn't downshift into 1st properly. I have been reading some posts on how to adjust the TV cable -- I'll give that a go tomorrow. I would have downshifted manually and checked it out that way but at this time in the morning that's a good way to get a ticket pronto. It did seem smoother -- not as strained seems a way to put it.
I'd attach a pic of the spacer I made but for some reason the camera flash card is reading as empty -- my wife might have transferred the images to a directory on the hard drive.
I'd attach a pic of the spacer I made but for some reason the camera flash card is reading as empty -- my wife might have transferred the images to a directory on the hard drive.
08-23-2002, 01:37 AM
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Car: 91 Z28
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Let me know how it go's when you get that TV cable ajusted. It would be nice to see a pic of it.
08-23-2002, 10:06 PM
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Hi Brian,
Adjusting the TV cable was easy. I followed the instructions in the tech article, drove the car and all was back to normal.
I found out that the flash card was erased somehow by the camera (might have been a low battery). Unfortunately, that had the pics of the spacer by itself. I glued the layers together with all-purpose plumbers plastic cement (used on various types of plastic pipes -- polyethylene wasn't specifically mentioned but it seems to have worked ok) and then milled the sides even with a cutting attachment in my drill press.
When I mounted it, I used, in order: TBI; RTV silicone; gasket; RTV silicone; spacer; RTV silicone; manifold. To mount the TBI I bought three 5/16" by 18 by 3 1/2" bolts. Underneath each of the heads I put three 5/16" grade 5 hardened steel washers. I would have used grade 5 bolts but Lowe's supply drawer jumped from 3" to 4". I think the unrated bolts are fine in this application. Hardware cost: ~ $1.50.
The gasket kit came with two injector pod gaskets, so I installed them. There is less thread engagement on the TORX bolts, so be sure to use threadlock lest they loosen and drop down in the thottle bores. I put a drop on the side of the bolt heads as well, after tightening, just to be sure. The curved stud that holds down the filter lid was too long after all this. I clipped about half the threaded portion on the top off and that seems about right. I have a jury rigged spacer for the wingnut right now. Danger: If you don't clip this stud there is a good chance you'll put a nice dimple in the middle of your hood.
I have decided to just leave the cruise control cable disconnected until I can obtain a used cable bracket to play around with. My wife will use this car for commuting back and forth to school starting Monday and I want to be able to switch back to known working parts. We have not used the cruise control yet anyway so that is not a big deal.
Performance wise, like I said, the engine feels less strained and a bit quicker. My wife was driving a slightly tweaked Chrysler turbo 2.5 LeBaron. With this mod the RS feels like it has about the same acceleration as that car whereas before the turbo 2.5 would have smoked it. I had a 5.0 Mustang conv a few years ago and we aren't in that territory yet, however.
I think what is happening is that at lower speeds (accelerating from a standing start) the snorkel restriction (size and hot air duct) has become the limiting factor. As the car begins to move and a ram-air effect develops in the stock intake, the restriction is less of a problem.
I am not willing to go to an open element -- I don't want to give up the driveability afforded by the factory items. I am thinking that a second snorkel could be taken straight forward towards the radiator. I would leave the hot air duct valve intact but cap the opening underneath. That would first force all the air to come through the original snorkel and be heated by the manifold. When the engine is at normal operating temperature the second snorkel would become functional. I am thinking/guesstimating that the air intake system from a TPI less the filters could be used as the "scoop" system for this second snorkel. I am not sure if that would work but an hour or two in the wrecking yard would probably answer that.
I'll attach some pics...
Kevin
Adjusting the TV cable was easy. I followed the instructions in the tech article, drove the car and all was back to normal.
I found out that the flash card was erased somehow by the camera (might have been a low battery). Unfortunately, that had the pics of the spacer by itself. I glued the layers together with all-purpose plumbers plastic cement (used on various types of plastic pipes -- polyethylene wasn't specifically mentioned but it seems to have worked ok) and then milled the sides even with a cutting attachment in my drill press.
When I mounted it, I used, in order: TBI; RTV silicone; gasket; RTV silicone; spacer; RTV silicone; manifold. To mount the TBI I bought three 5/16" by 18 by 3 1/2" bolts. Underneath each of the heads I put three 5/16" grade 5 hardened steel washers. I would have used grade 5 bolts but Lowe's supply drawer jumped from 3" to 4". I think the unrated bolts are fine in this application. Hardware cost: ~ $1.50.
The gasket kit came with two injector pod gaskets, so I installed them. There is less thread engagement on the TORX bolts, so be sure to use threadlock lest they loosen and drop down in the thottle bores. I put a drop on the side of the bolt heads as well, after tightening, just to be sure. The curved stud that holds down the filter lid was too long after all this. I clipped about half the threaded portion on the top off and that seems about right. I have a jury rigged spacer for the wingnut right now. Danger: If you don't clip this stud there is a good chance you'll put a nice dimple in the middle of your hood.
I have decided to just leave the cruise control cable disconnected until I can obtain a used cable bracket to play around with. My wife will use this car for commuting back and forth to school starting Monday and I want to be able to switch back to known working parts. We have not used the cruise control yet anyway so that is not a big deal.
Performance wise, like I said, the engine feels less strained and a bit quicker. My wife was driving a slightly tweaked Chrysler turbo 2.5 LeBaron. With this mod the RS feels like it has about the same acceleration as that car whereas before the turbo 2.5 would have smoked it. I had a 5.0 Mustang conv a few years ago and we aren't in that territory yet, however.
I think what is happening is that at lower speeds (accelerating from a standing start) the snorkel restriction (size and hot air duct) has become the limiting factor. As the car begins to move and a ram-air effect develops in the stock intake, the restriction is less of a problem.
I am not willing to go to an open element -- I don't want to give up the driveability afforded by the factory items. I am thinking that a second snorkel could be taken straight forward towards the radiator. I would leave the hot air duct valve intact but cap the opening underneath. That would first force all the air to come through the original snorkel and be heated by the manifold. When the engine is at normal operating temperature the second snorkel would become functional. I am thinking/guesstimating that the air intake system from a TPI less the filters could be used as the "scoop" system for this second snorkel. I am not sure if that would work but an hour or two in the wrecking yard would probably answer that.
I'll attach some pics...
Kevin
08-23-2002, 10:14 PM
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Here is a pic of the throttle bracket. You can see that I lifted it with some spacers but not the 14/16". Probably less than half that much. I had to slot the attachment points to the manifold so that I could slide the bracket forward about 1/4" or so. The forward mount had to have the back side cut away to allow the bolt head to pass through it. Kinda cheesy but it works. When I have a fresh bracket I can MIG weld something a bit nicer.
08-23-2002, 10:18 PM
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This cruise control cable laying loosely in place is what caused the interference before. I am thinking I might be able to mount it parallel to the throttle cable. The attachment on the throttle arm has less of a mechanical advantage though. I am not sure if the cruise control mechanism is up to exerting that much incrementally more force.
08-23-2002, 10:31 PM
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Here is the area that I was thinking about routing the second snorkel. Straight forward from the filter base towards the upper radiator cover meeting the TPI dual air intakes that attach to the plenum forward of the radiator. Hmmmm....
08-24-2002, 01:06 AM
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Car: 91 Z28
Engine: 305 TPI
Transmission: 5 speed
Axle/Gears: 3.42's
The second snorkel idea seems like a Good one. The spacer looks good. Thanks for taking the time to post all those pics, and thanks for all the info. I know I'll use some of these ideas down the road.
08-26-2002, 01:04 PM
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yeah i know what you mean. i had my brother nlaw get me a 1 1/8th inch spacer made from where he works at. couldnt get any smaller size. thats all they had. the bolts were about $.41 a piece.. ive only got 1.50 put into this. ill find out how good this mod will be at end of this week. thanks for the pics. ill try g=to get some of mine soon.
08-26-2002, 02:05 PM
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Car: 1991 Pontiac Firebird
Engine: 3.8
Transmission: 700r4
Axle/Gears: Dana 60
Hey guys, this is what I did for my 1" spacer and I didn't have to switch any of the cables around.
Grab urself a dremel tool with a bit the size of the bolt hole in the back of the throttle bracket on the intake. Pictured here
Now take the bolt out and lay down some towels so u don't get shavings everywhere and dremel it so the bolt hole size is the same size but make it longer so you can move the bolt forward and backward and so u can just tighten it down when you find it close enough. Do u guys get what I am saying? Its kinda hard to explain. You make it so u can move your bracket forward and still tighten it down because u have this path now where the bolt can be in place but u can move the bracket forward and backwards and then tighten the bolt down.
I do the highly suggest that you get urself a .5" spacer or smaller because it will save u the hassle, but if u already have the 1" spacer and u can't take it back then try this out.
Grab urself a dremel tool with a bit the size of the bolt hole in the back of the throttle bracket on the intake. Pictured here
Now take the bolt out and lay down some towels so u don't get shavings everywhere and dremel it so the bolt hole size is the same size but make it longer so you can move the bolt forward and backward and so u can just tighten it down when you find it close enough. Do u guys get what I am saying? Its kinda hard to explain. You make it so u can move your bracket forward and still tighten it down because u have this path now where the bolt can be in place but u can move the bracket forward and backwards and then tighten the bolt down.
I do the highly suggest that you get urself a .5" spacer or smaller because it will save u the hassle, but if u already have the 1" spacer and u can't take it back then try this out.
08-26-2002, 03:17 PM
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Engine: slowtacular L03 305
Transmission: slushem 700r4
Hey Kevin, this is completely off topic, but in the 4th pic wich cable is the tv cable? I would like to adjust mine but the tech article has pictures from a 2.8v6 so its hard to match everything up. 
08-26-2002, 09:20 PM
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"Do u guys get what I am saying? Its kinda hard to explain. You make it so u can move your bracket forward and still tighten it down because u have this path now where the bolt can be in place but u can move the bracket forward and backwards and then tighten the bolt down."
Yep. It is kinda hard to tell from the pic but that is what I did. Actually, when I was working on this it was about 11:00 PM and I used my hacksaw to section it and then bend it back with pliers. My shop/garage is all metal and if I had started up a die grinder or even a Dremel my neighbors wouldn't have been too pleased.
What kind of filter base are you using? When the base was off, yes, the cables all worked fine. When I installed the stock drop base, it pressed down on the cruise control cable slightly Top most cable). It seemed like it would work when I moved the gas pedal with the engine off. However, when I actually started it, the pressure was just enough to open the throttle and keep it open slightly -- made the engine rev up. The process of elimination confirmed that this cable was the trouble.
My wife and I have put ~ 200 miles on the car since I changed it and it seems stable. I kept a big ABC fire extinguisher in the back just in case something gas related decided to start acting up.
Yep. It is kinda hard to tell from the pic but that is what I did. Actually, when I was working on this it was about 11:00 PM and I used my hacksaw to section it and then bend it back with pliers. My shop/garage is all metal and if I had started up a die grinder or even a Dremel my neighbors wouldn't have been too pleased.
What kind of filter base are you using? When the base was off, yes, the cables all worked fine. When I installed the stock drop base, it pressed down on the cruise control cable slightly Top most cable). It seemed like it would work when I moved the gas pedal with the engine off. However, when I actually started it, the pressure was just enough to open the throttle and keep it open slightly -- made the engine rev up. The process of elimination confirmed that this cable was the trouble.
My wife and I have put ~ 200 miles on the car since I changed it and it seems stable. I kept a big ABC fire extinguisher in the back just in case something gas related decided to start acting up.
08-26-2002, 10:10 PM
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Engine: slowtacular L03 305
Transmission: slushem 700r4
Thanks kevin, i was getting it confused with my cruise control cable so know i know what i am looking at.
08-27-2002, 09:33 PM
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Success
Ok, some good news...
I picked up the air intake system from a TPI V6 RS and grafted on another snorkel from a TBI RS. I have the photo below.
Great part is that this mod will work *EASY*. Bad part is that I need to find a different snorkel -- one that comes straight out and level instead of slanting down like the stock TBI. I saw plenty of snorkels like that on the same diameter base so that will just have to wait a bit. You can see that a level one would mate up with the outlet from the TPI system.
The TPI system bolts right in -- I just left out the filters. The second snorkel retains a functioning vacuum operated heat riser.
In any event, I took the car out for a spin and *Wow* -- what a difference that second snorkel made. Much better power. I was actually staying even with a late 70s Z28 that tried to blow me away. :rockon:
All that and the TPI intake system isn't really even functional yet. I think if it had been pressurizing the housing (ram air) I would have pulled slightly ahead at speed.
So here is what I have done so far:
*Smoothed/ported TBI unit
*Extra gasket under injector pods
*No ring tack-welded in on air filter base
*No spacer ring under air filter base
*"Truck" type air housing lid with Fram filter
*14/16" spacer between TBI and manifold
*Second TBI snorkel -- both snorkels with functioning heat risers
*Air intake/filter housing from TPI V6 less the filters (not hooked up to snorkel yet)
I picked up the air intake system from a TPI V6 RS and grafted on another snorkel from a TBI RS. I have the photo below.
Great part is that this mod will work *EASY*. Bad part is that I need to find a different snorkel -- one that comes straight out and level instead of slanting down like the stock TBI. I saw plenty of snorkels like that on the same diameter base so that will just have to wait a bit. You can see that a level one would mate up with the outlet from the TPI system.
The TPI system bolts right in -- I just left out the filters. The second snorkel retains a functioning vacuum operated heat riser.
In any event, I took the car out for a spin and *Wow* -- what a difference that second snorkel made. Much better power. I was actually staying even with a late 70s Z28 that tried to blow me away. :rockon:
All that and the TPI intake system isn't really even functional yet. I think if it had been pressurizing the housing (ram air) I would have pulled slightly ahead at speed.
So here is what I have done so far:
*Smoothed/ported TBI unit
*Extra gasket under injector pods
*No ring tack-welded in on air filter base
*No spacer ring under air filter base
*"Truck" type air housing lid with Fram filter
*14/16" spacer between TBI and manifold
*Second TBI snorkel -- both snorkels with functioning heat risers
*Air intake/filter housing from TPI V6 less the filters (not hooked up to snorkel yet)
08-28-2002, 09:17 PM
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Yes, this second snorkel clears the stock air conditioning on the 91 RS
One person was wondering about that. I snapped a few more pics so you can see how the second snorkel was attached and how it lines up with the TPI air intake system.
Honest, guys, if you have a local U-Pull-It with a decent selection of cars, this has got to be one of the most inexpensive mods around --- but yes it does involve some (very) limited fabricating. I spent (maybe) $25 on these additional parts total. Nice part is that the air intake is factory engineered and will clear the stock hood. There is a tech article on this site about adding ram air ducting to the fog light area. Again, learn from my experiment and buy a level snorkel instead of using the stock TBI downward slanting one. I saw snorkels like that in the yard, I just cannot reel off what cars they were on.
Kevin
Honest, guys, if you have a local U-Pull-It with a decent selection of cars, this has got to be one of the most inexpensive mods around --- but yes it does involve some (very) limited fabricating. I spent (maybe) $25 on these additional parts total. Nice part is that the air intake is factory engineered and will clear the stock hood. There is a tech article on this site about adding ram air ducting to the fog light area. Again, learn from my experiment and buy a level snorkel instead of using the stock TBI downward slanting one. I saw snorkels like that in the yard, I just cannot reel off what cars they were on.
Kevin
08-28-2002, 09:30 PM
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Exterior shot
showing the area between the snorkels. Originally, I had cut the flanges on either side of the second snorkel with equal lengths. However, when I fitted it up I noticed that the little vacuum line clip on the bottom of the original housing interfered so I cut that flange back to clear it.
08-30-2002, 10:28 PM
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Done
Well, almost. It needs to be stripped and repainted.
Here it is... And all GM Factory parts... :rockon:
My wife and I took it out for a spin and you can really feel the ram air come in around 45-50 mph -- the car starts accelerating faster nicely. This is an added boost above what we got with the dual snorkels not being hooked up to the (now) main pressurized (and cooler) air supply. All this without a tremendous amount of induction roar like you'd get from an open element air filter. I know that sound is a lot of fun but it definitely attracts a lot of the wrong kind of attention.
Went on the interstate and accelerating from 70 to 90 for passing is much quicker.
Have fun!
Here it is... And all GM Factory parts... :rockon:
My wife and I took it out for a spin and you can really feel the ram air come in around 45-50 mph -- the car starts accelerating faster nicely. This is an added boost above what we got with the dual snorkels not being hooked up to the (now) main pressurized (and cooler) air supply. All this without a tremendous amount of induction roar like you'd get from an open element air filter. I know that sound is a lot of fun but it definitely attracts a lot of the wrong kind of attention.
Went on the interstate and accelerating from 70 to 90 for passing is much quicker.
Have fun!
08-30-2002, 10:51 PM
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vrooom305: "Is there anything good about having a TBI spacer?"
Yes, it does add volume to the intake manifold plenum and that boosts power (at least on the stock manifold). It can also serve as a heat insulator depending on the material used (helps keep the intake charge a little cooler).
I like those benefits but with mine it was a means to an end as well: It allowed me to keep the stock air cleaner assembly at a static height while moving the TBI unit up. That allows you to eliminate the stock TBI ring spacer that everyone complains about and not have to go to a custom hood (the spacer only allows air flow to come from the top but a great deal of air flow into a carb or TBI unit comes from the sides -- or CAN if you allow it to).
Yes, it does add volume to the intake manifold plenum and that boosts power (at least on the stock manifold). It can also serve as a heat insulator depending on the material used (helps keep the intake charge a little cooler).
I like those benefits but with mine it was a means to an end as well: It allowed me to keep the stock air cleaner assembly at a static height while moving the TBI unit up. That allows you to eliminate the stock TBI ring spacer that everyone complains about and not have to go to a custom hood (the spacer only allows air flow to come from the top but a great deal of air flow into a carb or TBI unit comes from the sides -- or CAN if you allow it to).
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