From what I’ve read, the intake would need special spacers to clamp properly on the gasket. If it’s running so poorly, I’d believe nothing the seller says.
Need help w/ a few things! 🙏 TBI conversion to Carb.
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Do you have a link on that? I read that you need special washers to bolt up proper...and possibly modify the intake gasket...but not sure on spacer. 🤔
As stated previously, I have a buddy coming by who has owned some very nice classic muscle cars.. Vette, Nova, and more. Hopefully he can give a noob some first hand guidance. 🙏
As I'm driving the car more, I suppose it's not that bad. I'm not sure if it is just me but it seems to be running "a little" better. Maybe some timing and carburetor adjustment are what are the biggest problems. 🤔 Unfortunately, I don't know where to start or begin without a little help and guidance.
I'll work on tightening up any loose ends, checking vacuum, exhaust, and fuel. She seems to have a slight kick now when slightly punching it. If I floor it, there's more of a hesitation and weak take-off. If I just give it a quick "half pedal", it seems more proper.
I'll try not to think too far ahead. I'm already looking at what add-ons I can bolt up for more HP. I'm convinced that the 2.xx gearing isn't helping, and a tune up and new wires, distributor, etc. are in order.
Short of putting a different engine in, I'm not sure if it's worth putting any money into - being that it's a low compression "truck engine". A few people are telling me to slap on some 305 heads. Others are telling me not to bother. 🥴
As I'm driving the car more, I suppose it's not that bad. I'm not sure if it is just me but it seems to be running "a little" better. Maybe some timing and carburetor adjustment are what are the biggest problems. 🤔 Unfortunately, I don't know where to start or begin without a little help and guidance.
I'll work on tightening up any loose ends, checking vacuum, exhaust, and fuel. She seems to have a slight kick now when slightly punching it. If I floor it, there's more of a hesitation and weak take-off. If I just give it a quick "half pedal", it seems more proper.
I'll try not to think too far ahead. I'm already looking at what add-ons I can bolt up for more HP. I'm convinced that the 2.xx gearing isn't helping, and a tune up and new wires, distributor, etc. are in order.
Short of putting a different engine in, I'm not sure if it's worth putting any money into - being that it's a low compression "truck engine". A few people are telling me to slap on some 305 heads. Others are telling me not to bother. 🥴
That connects to the air cleaner, which was disconnected for the photo. (If I'm on the same page) 🙂
UPDATE:
I've yet to mess with the timing. A buddy came by and realized that the secondaries on the carb. were not opening. We fiddled with it quite a bit...but seems to not be working properly. Not sure why. Opens or partially opens when it wants to. Buddy couldn't see any interference. 🤷♂️
So...the next plan of attack is:
New Vortec heads
New rpm air gap vortec intake
New edelbrock carb. (Not sure what CFM - suggestions welcome)
New XE268H cam, with corresponding pushrods and self aligning rockers.
New distributor, wires, etc.
Long tube headers
3.73 posi
Any suggestions to the above combo are welcomed. This is the combo I've came up with after tons of reading. Budget is certainly a priority.
My only concern is the original 1995 TBI block (truck engine, low compression)...which means I may have to have some head work done and or a complete rebuild later.
Thoughts?
I've yet to mess with the timing. A buddy came by and realized that the secondaries on the carb. were not opening. We fiddled with it quite a bit...but seems to not be working properly. Not sure why. Opens or partially opens when it wants to. Buddy couldn't see any interference. 🤷♂️
So...the next plan of attack is:
New Vortec heads
New rpm air gap vortec intake
New edelbrock carb. (Not sure what CFM - suggestions welcome)
New XE268H cam, with corresponding pushrods and self aligning rockers.
New distributor, wires, etc.
Long tube headers
3.73 posi
Any suggestions to the above combo are welcomed. This is the combo I've came up with after tons of reading. Budget is certainly a priority.
My only concern is the original 1995 TBI block (truck engine, low compression)...which means I may have to have some head work done and or a complete rebuild later.
Thoughts?
I guess you were on to something. There is a computer...passenger kick panel. Just pulled the panel today for something else. I wasn't aware that this could have had a computer. 😬
Couple of things. For the casting number for the block, look on the shoulder/flange where the bell housing attaches. Should appear on the driver's side. May only show as a year/CID ident.
The original t-mission likely would have been a TH200R4 which was a four speed and did have the lockup in fourth. In that era there were two ways to achieve the lockup. The older versions used a VOES switch which activated the lock up and a dual terminal plunger switch on the brake pedal that had the second pair of terminals wired to "short" the circuit and by doing so deactivate the lockup until the vehicle started forward again. The newer iteration did it through the first generation CCC or EEE or ECM, which could be found behind the passenger's side toe/kick panel under the dash. I am thinking that only as much of the wiring as was needed to get the car to start and run was re-attached when the engine swap was done. Most of the power wires for everything generally came together on the 3/8 ths stud located on the solenoid above the starter. These are identifiable based on having a fusible link embedded in them and being #10 primary or so. You may find that only the wires for the dash/key/et al are now attached and that two of the primary wires are just hanging there. At least one of them would have been power to the CCC/ECM.
The pic of the carb says to me that it is a 2 Barrel, not a four. Your picture shows the primary side of the carb c/w with the choke flap but a four barrel would come with the back half of the air horn showing as well. The name Rochester "Dual" should be stamped or embossed on the carb body somwhere visible. In the pic to the left and after the choke is the EGR valve which is the Exhaust Gas Recirculation Valve and it doesn't seem to be showing a vacuum hose. This was actuated by vacuum from the carb that got delivered to a vacuum tree that was screwed into the t-stat housing. As the engine warmed up, heat from the coolant would cause the element inside the tree to move and by doing so open and close various ports which allowed vacuum to get delivered to whatever components used it, like the EGR for example. The tree may still be there and screwed into the thermostat housing, but minus its vacuum hoses, i.e. abandoned. its ports wouldn't have needed to be blocked, it is just a distribution unit. The feed port for it on the carb would have had a rubber cap fitted over it to block it off. The suffix "EME" pretty much means that it is electrically or electronically controlled, meaning how it operates is governed by the EEE/ECM. The same probably holds true for the distributor. The easiest way to confirm that is physical; The HEI's had a large distributor cap, the ECM controlled units did not. The HEI, with some exceptions, came with a vacuum advance unit attached to the distributor base that uses vacuum delivered from a port on the carb. On the electronic, ECM controlled unit, the vacuum advance unit is missing; eliminated as un-needed. With the ECM on line and working properly, all the fuel/ignition/timing functions were controlled by the ECM in response to input from various sensores, like the coolant temp sensor, for example.
In a first generation ECM controlled environment, the carb and distributor are a matched set and, should the ECM be disconnected and/or removed, neither will work well by themselves or without the other. it would have been easy for the swapper to have just grabbed the carb and distributor from the old mill and dropped them on the replacement. The engine initial timing would have been set to the ECM standard as it handles all the advance that is subsequently needed as the engine accelerates. Your knock could be timing, or it could be low octane gas or other issues. You haven't mentioned if you have done any oil changes since you purchased this vehicle. Don't assume that the mill came with fresh oil and a new filter. Also don't assume that it came from a low mileage car that got regular maintenance. When you do your next oil change, keep the filter and fillet it; that being cut away the canister and unfold the pleated filter material to check it for anything foreign or nasty looking. Oh, yeah, this controller box or ECM is NOT a computer. At best all it can do is accept incoming values of electrical current that can change based on resistance or current flow and alter the actions of the components it controls accordingly. It has no cpu and no memory. AT best it is just a bunch of switches that respond to measured current fluctuations. No one offers new replacements and for the most part it is sort of an idiot savant in an aluminum case. If your knock is timing, about the only change you can make to the stock timer is to retard or advance the base value by a degree or two. Losing a degree may help with your knock but it can also affect the top end horsepower (Like that is likely to be of major importance) Tweaking the timer is best done wiith a dial-back timing light that will give you both the base timing and the all in--Read The Instructions before using. Also don't believe the timing mark on the crank damper. The rubber isolaton ring that separates the inner section from its outer half can deteriorate or rot letting the two rings shift with respect to each other. It's a function of old age. There are kits available to do a static timing check on the engine using #1 piston at TDC as a reference point. You will be finding out as you go along that the local tool truck or tool supply shop is about to become your best friend.
Above all this is going to require patience. Do as you have described, eliminate one problem or issue at a time and move on to the next. Be aware that there is a definite learning curve attached to all this; and for myself I haven't quit learning yet.
Nick
The original t-mission likely would have been a TH200R4 which was a four speed and did have the lockup in fourth. In that era there were two ways to achieve the lockup. The older versions used a VOES switch which activated the lock up and a dual terminal plunger switch on the brake pedal that had the second pair of terminals wired to "short" the circuit and by doing so deactivate the lockup until the vehicle started forward again. The newer iteration did it through the first generation CCC or EEE or ECM, which could be found behind the passenger's side toe/kick panel under the dash. I am thinking that only as much of the wiring as was needed to get the car to start and run was re-attached when the engine swap was done. Most of the power wires for everything generally came together on the 3/8 ths stud located on the solenoid above the starter. These are identifiable based on having a fusible link embedded in them and being #10 primary or so. You may find that only the wires for the dash/key/et al are now attached and that two of the primary wires are just hanging there. At least one of them would have been power to the CCC/ECM.
The pic of the carb says to me that it is a 2 Barrel, not a four. Your picture shows the primary side of the carb c/w with the choke flap but a four barrel would come with the back half of the air horn showing as well. The name Rochester "Dual" should be stamped or embossed on the carb body somwhere visible. In the pic to the left and after the choke is the EGR valve which is the Exhaust Gas Recirculation Valve and it doesn't seem to be showing a vacuum hose. This was actuated by vacuum from the carb that got delivered to a vacuum tree that was screwed into the t-stat housing. As the engine warmed up, heat from the coolant would cause the element inside the tree to move and by doing so open and close various ports which allowed vacuum to get delivered to whatever components used it, like the EGR for example. The tree may still be there and screwed into the thermostat housing, but minus its vacuum hoses, i.e. abandoned. its ports wouldn't have needed to be blocked, it is just a distribution unit. The feed port for it on the carb would have had a rubber cap fitted over it to block it off. The suffix "EME" pretty much means that it is electrically or electronically controlled, meaning how it operates is governed by the EEE/ECM. The same probably holds true for the distributor. The easiest way to confirm that is physical; The HEI's had a large distributor cap, the ECM controlled units did not. The HEI, with some exceptions, came with a vacuum advance unit attached to the distributor base that uses vacuum delivered from a port on the carb. On the electronic, ECM controlled unit, the vacuum advance unit is missing; eliminated as un-needed. With the ECM on line and working properly, all the fuel/ignition/timing functions were controlled by the ECM in response to input from various sensores, like the coolant temp sensor, for example.
In a first generation ECM controlled environment, the carb and distributor are a matched set and, should the ECM be disconnected and/or removed, neither will work well by themselves or without the other. it would have been easy for the swapper to have just grabbed the carb and distributor from the old mill and dropped them on the replacement. The engine initial timing would have been set to the ECM standard as it handles all the advance that is subsequently needed as the engine accelerates. Your knock could be timing, or it could be low octane gas or other issues. You haven't mentioned if you have done any oil changes since you purchased this vehicle. Don't assume that the mill came with fresh oil and a new filter. Also don't assume that it came from a low mileage car that got regular maintenance. When you do your next oil change, keep the filter and fillet it; that being cut away the canister and unfold the pleated filter material to check it for anything foreign or nasty looking. Oh, yeah, this controller box or ECM is NOT a computer. At best all it can do is accept incoming values of electrical current that can change based on resistance or current flow and alter the actions of the components it controls accordingly. It has no cpu and no memory. AT best it is just a bunch of switches that respond to measured current fluctuations. No one offers new replacements and for the most part it is sort of an idiot savant in an aluminum case. If your knock is timing, about the only change you can make to the stock timer is to retard or advance the base value by a degree or two. Losing a degree may help with your knock but it can also affect the top end horsepower (Like that is likely to be of major importance) Tweaking the timer is best done wiith a dial-back timing light that will give you both the base timing and the all in--Read The Instructions before using. Also don't believe the timing mark on the crank damper. The rubber isolaton ring that separates the inner section from its outer half can deteriorate or rot letting the two rings shift with respect to each other. It's a function of old age. There are kits available to do a static timing check on the engine using #1 piston at TDC as a reference point. You will be finding out as you go along that the local tool truck or tool supply shop is about to become your best friend.
Above all this is going to require patience. Do as you have described, eliminate one problem or issue at a time and move on to the next. Be aware that there is a definite learning curve attached to all this; and for myself I haven't quit learning yet.
Nick
Thanks for the reply Nick! I'll definitely give the bell housing a shot and try to find #'s. If it is stamped on top-rear passenger side, I have wiring harnesses and other stuff in the way...and just can't see anything. I'll give your suggestion a shot.
I'm a bit confused over the comments of the trans having a lock-up or non lock-up. 🥴 Someone here even mentioned needing a new trans that isn't controlled by the..(something like that). I do know that it has 3 gears, and the pan has the slant in it...so I'm assuming th350. As far as we know, that is the original. 🤞 In either case, are you saying that the trans may or may not be locking up - causing poor performance?
The carb. definitely has 4 barrels. Choke plate is missing, and secondary "flap" opens irregularly. Sometimes it opens, sometimes not.
I will definitely take a look at all of your suggestions. I haven't changed the oil yet, as I will still trying to figure out what type of cam was in there (flat tappet or roller) - pretty sure not roller but..
Engine supposedly had 100k miles on it. 🤷♂️
I think my course of action will be getting rid of / bypassing all the ECM and emissions related stuff (and buying new parts 😒).
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