Help me spend $1500 on performance upgrades to 1981 C3
02-15-2005, 08:38 PM
#41
Melting Slicks
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Originally Posted by Gator81
OK, here we go... another '81 heard from! 
Reading through the posts, I'm picking up a vibe that your car's not been kept in exactly pristine condition. In particular, I'm wondering about that ex-computer and what it means for the carb, distributor, and tranny. You said it had a 'glass spring, so I'm assuming it's an automatic. The original computer controlled the mixture on the front half of the carb, the timing advance, and the top-gear lockup in the tranny. If some Bubba has gone through there with a meat ax, I suspect there are things that aren't working right. So, first thing: have the current setup evaluated by someone who knows both computer and non-computer Chevrolets.
The second thing I'm questioning is what some of the others did: is this budget all there is for the car, or is this just the "power" part of the budget? The reason I ask is that all the power in the world won't make you happy if the car rides like a garbage truck and handles like a pig. After 24 years, rubber parts are likely to be dried out, cracked, broken, or just plain missing. That includes all the bushings in the suspension. That can make the car dangerous. Then, there's brakes. Old Vettes have bad brakes, especially in humid climates. Humidity condenses in the master cylinder, gets into the calipers, and causes rust. I seriously urge you to have the suspension and brakes checked out, if you haven't already, before you blow the budget. Including new springs, a sway bar, shocks, etc., I spent nearly $3K fixing all that on my '81.
Now, let's assume you're ahead of the game, and all that stuff (above) is good to go. Then start with the exhaust. If it doesn't hurt your conscience and the law's not lookin', go with headers and straight dual exhaust, turbo mufflers. Do the ceramic coating on the headers, and go with stainless pipes. In the humid climate, you'll be glad you did. That's maybe $800-$900 installed. Drive it like this for awhile and see if you're happy, or you still need more go-fast.
If more is still better, next thing is the cam. A Crane 2040 (duration 210*/216* @ .050", lift .440"/.454) is a good cam for that engine, and it's smog-legal. Without the computer, you can do more cam, but with stock compression you probably won't like how it runs, especially with that automatic tranny. By the time you have that cam, new lifters, new timing set, and all the piecy-parts that go with it, installed, you'll have used up your $1500 and you'll have a nice warmed-up 350.
Reading through the posts, I'm picking up a vibe that your car's not been kept in exactly pristine condition. In particular, I'm wondering about that ex-computer and what it means for the carb, distributor, and tranny. You said it had a 'glass spring, so I'm assuming it's an automatic. The original computer controlled the mixture on the front half of the carb, the timing advance, and the top-gear lockup in the tranny. If some Bubba has gone through there with a meat ax, I suspect there are things that aren't working right. So, first thing: have the current setup evaluated by someone who knows both computer and non-computer Chevrolets.
The second thing I'm questioning is what some of the others did: is this budget all there is for the car, or is this just the "power" part of the budget? The reason I ask is that all the power in the world won't make you happy if the car rides like a garbage truck and handles like a pig. After 24 years, rubber parts are likely to be dried out, cracked, broken, or just plain missing. That includes all the bushings in the suspension. That can make the car dangerous. Then, there's brakes. Old Vettes have bad brakes, especially in humid climates. Humidity condenses in the master cylinder, gets into the calipers, and causes rust. I seriously urge you to have the suspension and brakes checked out, if you haven't already, before you blow the budget. Including new springs, a sway bar, shocks, etc., I spent nearly $3K fixing all that on my '81.
Now, let's assume you're ahead of the game, and all that stuff (above) is good to go. Then start with the exhaust. If it doesn't hurt your conscience and the law's not lookin', go with headers and straight dual exhaust, turbo mufflers. Do the ceramic coating on the headers, and go with stainless pipes. In the humid climate, you'll be glad you did. That's maybe $800-$900 installed. Drive it like this for awhile and see if you're happy, or you still need more go-fast.
If more is still better, next thing is the cam. A Crane 2040 (duration 210*/216* @ .050", lift .440"/.454) is a good cam for that engine, and it's smog-legal. Without the computer, you can do more cam, but with stock compression you probably won't like how it runs, especially with that automatic tranny. By the time you have that cam, new lifters, new timing set, and all the piecy-parts that go with it, installed, you'll have used up your $1500 and you'll have a nice warmed-up 350.
My car I believe was given up on after 22 yrs. (how long the 2nd woman owner had it). I believe now that it was "bubba'd". Still haven't got it off the jack stands and got the hood unstuck to check the distrubutor. You were correct in assuming it is an automatic. Alot of things are fine including the brakes, interior (except carpet faded), 4 yr. old paint job (which is still pretty good), new tires, most everything in good working order. But the usual suspect of repairs are needed such as I'm still working on the rear wheel bearing (another story in itself), parking break not working, cruise not working, speedo jumping, HOOD STUCK CLOSED, power door locks not working, dash lights are touchy.
Now the supsension is in so so shape. Alot of the rubber bushing are showing their age, but are all still in one piece. Steering seems okay, a little loose, yet adequate for now. Frame is in good shape, and the motor runs just okay if you know what I mean. I drove it back after buying it for 2 1/2 hours at 70 and the gages never jumped, and it ran pretty smooth. Minor shake and shimmy around 30-45 range. It just doesn't have any umpfth...but, it's the original engine, that has been "overhauled". Not sure at this point what that entailed.
As far as my budget...I really don't have one, but I had to start with some realistic number. I can afford more upgrades easily and this was bought as a fun car, not a daily driver. I am a bit conservative with my $$$ however, and wish to do alot of the work myself, and told myself this when I started looking for a vette. I am willing to learn (as I did with my tortureous rear spindle removal), and I'm not scared to ask questions. I learning alot about the motor, just don't have the knowledge at this time to adequately assess the situation, and that's where you guys, and my mechanic come into play. And I'm telling you, you guys are great!!
By the time I get through with some of this stuff on my car, you will all know it quite well. So, after I finally get my rear spindle back in, I'm off to see my NON-BUBBA mechanic friend for a good once over with him.
Thanks again guys for the replies, and I'll keep you informed. Be looking for the Rear End Noise Saga continues part 3 thread soon....
02-15-2005, 10:20 PM
#42
Drifting
Lets see..... The first thing you need to do is get the hood open.
The first modification you need to do is headers and a true dual exhaust if the law allows.
Then, sense I believe in working with what you already have, take the heads and have a street port job done on them. Don't forget a three angle valve job.
Now is the time for a cam. GO EASY. Too big of a cam is the worst mistake you can make.
If you can do most of the work yourself you should be able to do this for $1500.
Or, I've seen reman turbochargers sell on e-Bay for $250. You could piece the rest of it together for $1500 and it will do everything all the heads, headers and cams can do and probably more. Be a lot easier to live with to.
BigBlockk
Later.....
The first modification you need to do is headers and a true dual exhaust if the law allows.
Then, sense I believe in working with what you already have, take the heads and have a street port job done on them. Don't forget a three angle valve job.
Now is the time for a cam. GO EASY. Too big of a cam is the worst mistake you can make.
If you can do most of the work yourself you should be able to do this for $1500.
Or, I've seen reman turbochargers sell on e-Bay for $250. You could piece the rest of it together for $1500 and it will do everything all the heads, headers and cams can do and probably more. Be a lot easier to live with to.
BigBlockk
Later.....
02-16-2005, 12:52 PM
#43
CFOT Attention Whore
whoa, there, BigBlockk. with all due respect, that might be an option for many of us but clearly our good friend here is not yet ready to tackle an engineering project of that magnitude. installing a turbo system on one of our cars is quite a project and i doubt that even handling most of the heavy lifting yourself, you could cobble together a functional and reliable system for that budget.
maybe TT or even merlin (he still around?) could chime in as they both have experience with that type of system.
your absolutely right about that hood. at this point, all these discussions are pointless if you can't see what you have to work with!
maybe TT or even merlin (he still around?) could chime in as they both have experience with that type of system.
your absolutely right about that hood. at this point, all these discussions are pointless if you can't see what you have to work with!
02-16-2005, 01:55 PM
#44
Melting Slicks
Re-working old heads is a waste of money in my opinion. How many here have a flow bench to check them? If they have to be sent out for porting and a valve job, you'll be throw throwing good money away. Even with a good port job you won't be able to touch the flow of the Vortecs or aluminum heads.
02-16-2005, 08:40 PM
#45
Melting Slicks
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Finally got the car off of the jack stands, and the distributor is the original HEI. I wonder how that Bubba mechanic even got this thing running half way decent with the computer unhooked......
I was just remembering that the former owner saying something about it fouling plugs.....duh...wonder why.
Oh well, on to step two........new (old) conventional distrib., but not till I let my "bubba" check it out first.
I was just remembering that the former owner saying something about it fouling plugs.....duh...wonder why.
Oh well, on to step two........new (old) conventional distrib., but not till I let my "bubba" check it out first.
02-16-2005, 11:45 PM
#46
Melting Slicks
Well, there you are, right there! 
Sounds like you're on the right track. I just hope you don't expect it to be a short trip... 
Hey, I used to live in a little place called Ovette (how ironic!), not far from Laurel. Do you know that area?
Sounds like you're on the right track. I just hope you don't expect it to be a short trip... Hey, I used to live in a little place called Ovette (how ironic!), not far from Laurel. Do you know that area?
Last edited by Gator81; 02-22-2005 at 03:29 PM.
02-16-2005, 11:59 PM
#47
Melting Slicks
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I am familiar with the name as I use to live in Hattiesburg about 20 years ago......but not sure if I blinked going through their or not....lol...
02-17-2005, 12:07 AM
#48
If you're scraping the computer control. You may need to include a carb in that upgrade. The 81 (only year) came with a computer controlled carb and it won't perform without the computer. Check to see if there's wires (or just the connector) going into the top front of the carb.
If you're going to nix the carb/ECM/dist stuff, sell it here on the forum. Some of us can use those parts, the emissions stuff too.
If you're going to nix the carb/ECM/dist stuff, sell it here on the forum. Some of us can use those parts, the emissions stuff too.
02-17-2005, 12:14 AM
#49
Melting Slicks
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See now y'all are confusing this country boy!! I have read on this board where a few folks have stated that the Quadrajet is adjustable, and would work fine without the computer hooked up. Man......me and "bubba" got to hook up soon..... 
02-17-2005, 12:52 AM
#50
I'm not a guru or anything, I’m sure someone will chime in an tell me if I’m wrong. But I have worked with and rebuilt one of the 81 electronic carbs. It uses a PWM signal to run the metering valve solenoid. This is what adjusts the lean/rich mixture setting. Under normal operation the oxygen sensor senses the exhaust and the ECM adjusts the mixture accordingly. If there's no ECM or it's failed the mixture will default to a richer mixture. If it’s running well I’m sure it’s capable of supporting more power via engine mods.
So, without ECM the engine will run and not too bad. It will probably run rich. I can't see that being a good performance choice. Any black building up on the ceramic of the plugs? (fouling). Note: Someone on the forum said that the rear barrels of the carb are not ECM metered.
My suggestion is: Decide whether or not to keep the factory electronics. If you do decide to get away from it and you're looking for performance, sell the E-carb, ECM, etc to someone in CA, AZ, or elsewhere who needs to pass emissions and put the money towards something that will give you performance.
So, without ECM the engine will run and not too bad. It will probably run rich. I can't see that being a good performance choice. Any black building up on the ceramic of the plugs? (fouling). Note: Someone on the forum said that the rear barrels of the carb are not ECM metered.
My suggestion is: Decide whether or not to keep the factory electronics. If you do decide to get away from it and you're looking for performance, sell the E-carb, ECM, etc to someone in CA, AZ, or elsewhere who needs to pass emissions and put the money towards something that will give you performance.
02-17-2005, 03:55 AM
#51
Burning Brakes
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Good post! Some thoughts for you:
1) Lots of folks here who run the small blocks like the DynoMax ceramic coated headers. Good power for a great price. I just wish they made them for the big blocks!
2) Any chance you can restore the computer system to work properly in the car? It may be cheaper than finishing what Bubba started in ripping out and replacing more parts... Ask your mechanic to look into this option and see if it makes sense for you.
3) With the computer/fuel delivery/spark situation sorted out and a set of headers plus true duals you'll likely hit the $1500 if you are paying a mechanic. Do this much and see how it runs. Then map out further mods to build on what you have done so far. Of course, be sure the car is safe - check brakes, tires, and suspension before doing anything else.
1) Lots of folks here who run the small blocks like the DynoMax ceramic coated headers. Good power for a great price. I just wish they made them for the big blocks!
2) Any chance you can restore the computer system to work properly in the car? It may be cheaper than finishing what Bubba started in ripping out and replacing more parts... Ask your mechanic to look into this option and see if it makes sense for you.
3) With the computer/fuel delivery/spark situation sorted out and a set of headers plus true duals you'll likely hit the $1500 if you are paying a mechanic. Do this much and see how it runs. Then map out further mods to build on what you have done so far. Of course, be sure the car is safe - check brakes, tires, and suspension before doing anything else.
Last edited by djcwardog; 02-17-2005 at 03:58 AM.
02-17-2005, 07:31 AM
#52
Are you sure that the HEI is the original or if it's an earlier non-computer controlled one? If it's the original then there'll be problems with the advance (or lack of it!). Why was the computer disconnected? Is it still in place (in front of the battery)? Hooking up the computer again & fitting the original E4ME Q-jet (computer controls the mixture from the primaries, secondaries work the same as "normal" Q-jets) will get you a big increase in power ie. it'll start running as it should. If the computer was disconnected because it was fried, or the original Q-jet is long gone, then you could fit a "normal" dist from an earlier model eg 1980, & set it up as a non-computer controlled C3.
Once you get the engine running correctly (either with a computer controlled system or an earlier non-computer controlled one, NOT a mix of the two!) then you can start bumping up the power. Biggest improvement I ever got was from fitting dual pipes (no cat). A free improvement (the best sort) was gained by advancing the base timing from 6* to 11*BTDC. This really improved throttle response, esp at low engine speeds. If you get a non-computer controlled carb & dist fitted then recurving the dist will do the same thing (plenty of people here can advise on it).
If you do end up without the (much maligned) computer then the trans converter lockup function won't work. This locks the converter solid when in "top" gear & results in turning 2700rpm @70mph instead of the normal 3000rpm with stock 2.87:1 rear (prevents heat build up in the trans, increases fuel economy measurably & is better on the ears with loud pipes
). Hooking up the TCC to lockup if there's no computer fitted is an easy job that many people skip doing.
If you're capable of pulling rear spindles apart then the type of engine work being talked about won't be a great problem for you. Just get the shop manual for the '81 (the expensive one, not a Haynes or "All years" type) & you'll find that it's worth its weight in gold. Swapping an intake manifold is easy: once the carb is off (& you've photographed, tagged & memorised the position of all the vacuum pipes) it's only a few bolts to change it. But once the manifold is off then it's not that much more work to go on & change the cam I think your best bet, for starters, is to get the thing running correctly b4 worrying about heads & cams. Whether it involves the computer or not is up to you (respectable amounts of power can be achieved with the computer still in control, but if you want serious gobs of power then the computer becomes a hindrance). Once it's running correctly then I'd strongly recommend fitting dual 2 1/2" pipes b4 doing anything else. Even with the stock manifolds & mufflers still in place that mod gave mine a big "seat of the pants determined" improvement in power (& the system I took off had a "test pipe" in place of the cat, so I didn't have a cat strangling it). Whatever you do to the motor afterwards won't mean scrapping those exhausts. The only possible future problem with dual pipes is having to cut them about to fit Headers. For this reason it would be worth considering fitting Headers & then getting duals bent up to connect to them as your first enhancement. I've got the Dynomax ceramic coated ones & am very happy with them. With the stock manifolds & dual pipes I found that mine was running strong up unto high revs, at which point it felt like it was holding back. This was due to the restrictive tubular manifolds (which may look impressive, but are junk for flow IMHO). Headers now let it run strong up unto the red line. This is with the stock heads still in place, so when I get some new heads on it should really wake up.
Get it running right, fit decent exhausts & then come back here for advice & suggestions on further mods. Also, it would be prudent to check out the condition of the UJs while you're under the rear end. The advice on checking out the brakes & suspension is very good. Faster is NOT quicker & it's easy to build an engine that outperforms the suspension & brakes (been there, done that & it's very painful both physically & financially
). All mods in sig below.
Hi Gator Ovette? Cool! 
Once you get the engine running correctly (either with a computer controlled system or an earlier non-computer controlled one, NOT a mix of the two!) then you can start bumping up the power. Biggest improvement I ever got was from fitting dual pipes (no cat). A free improvement (the best sort) was gained by advancing the base timing from 6* to 11*BTDC. This really improved throttle response, esp at low engine speeds. If you get a non-computer controlled carb & dist fitted then recurving the dist will do the same thing (plenty of people here can advise on it).
If you do end up without the (much maligned) computer then the trans converter lockup function won't work. This locks the converter solid when in "top" gear & results in turning 2700rpm @70mph instead of the normal 3000rpm with stock 2.87:1 rear (prevents heat build up in the trans, increases fuel economy measurably & is better on the ears with loud pipes
). Hooking up the TCC to lockup if there's no computer fitted is an easy job that many people skip doing.If you're capable of pulling rear spindles apart then the type of engine work being talked about won't be a great problem for you. Just get the shop manual for the '81 (the expensive one, not a Haynes or "All years" type) & you'll find that it's worth its weight in gold. Swapping an intake manifold is easy: once the carb is off (& you've photographed, tagged & memorised the position of all the vacuum pipes) it's only a few bolts to change it. But once the manifold is off then it's not that much more work to go on & change the cam
I think your best bet, for starters, is to get the thing running correctly b4 worrying about heads & cams. Whether it involves the computer or not is up to you (respectable amounts of power can be achieved with the computer still in control, but if you want serious gobs of power then the computer becomes a hindrance). Once it's running correctly then I'd strongly recommend fitting dual 2 1/2" pipes b4 doing anything else. Even with the stock manifolds & mufflers still in place that mod gave mine a big "seat of the pants determined" improvement in power (& the system I took off had a "test pipe" in place of the cat, so I didn't have a cat strangling it). Whatever you do to the motor afterwards won't mean scrapping those exhausts. The only possible future problem with dual pipes is having to cut them about to fit Headers. For this reason it would be worth considering fitting Headers & then getting duals bent up to connect to them as your first enhancement. I've got the Dynomax ceramic coated ones & am very happy with them. With the stock manifolds & dual pipes I found that mine was running strong up unto high revs, at which point it felt like it was holding back. This was due to the restrictive tubular manifolds (which may look impressive, but are junk for flow IMHO). Headers now let it run strong up unto the red line. This is with the stock heads still in place, so when I get some new heads on it should really wake up.Get it running right, fit decent exhausts & then come back here for advice & suggestions on further mods. Also, it would be prudent to check out the condition of the UJs while you're under the rear end. The advice on checking out the brakes & suspension is very good. Faster is NOT quicker & it's easy to build an engine that outperforms the suspension & brakes (been there, done that & it's very painful both physically & financially
). All mods in sig below.Hi Gator
Ovette? Cool!
Last edited by UKPaul; 02-17-2005 at 07:50 AM.
02-17-2005, 09:53 AM
#53
Melting Slicks
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Paul....I'm not exactly sure why the computer was unhooked, other than the sellers mechanic told me he just couldn't keep the car running correctly with it hooked up.
How can you tell if the HEI is an old one, or new one. I did check to see if their was a vac. advance and I didn't see one.
Thanks for you long and informative post, and how did my car get in the UK? Yours looks exactly like mine in your sig pic!
I'm going to take my car in to a chevy mechanic (he's old and new school) and has his own shop, while working full time for a local chevy dealer. As suggested, after getting the distrib./carb/tuning problem out of the way (with or without ECM - which I prefer not to have), I think I'm going the header/true dual exhaust route while dropping the cat completely. After looking over everything, It really doesn't look to difficult a job adding the headers.....I AIN'T SCARED!!
Thanks again for all the comments, this has been an extremely informative message string!!
How can you tell if the HEI is an old one, or new one. I did check to see if their was a vac. advance and I didn't see one.
Thanks for you long and informative post, and how did my car get in the UK? Yours looks exactly like mine in your sig pic!
I'm going to take my car in to a chevy mechanic (he's old and new school) and has his own shop, while working full time for a local chevy dealer. As suggested, after getting the distrib./carb/tuning problem out of the way (with or without ECM - which I prefer not to have), I think I'm going the header/true dual exhaust route while dropping the cat completely. After looking over everything, It really doesn't look to difficult a job adding the headers.....I AIN'T SCARED!!
Thanks again for all the comments, this has been an extremely informative message string!!
02-17-2005, 10:58 AM
#54
Originally Posted by MsVetteMan
How can you tell if the HEI is an old one, or new one. I did check to see if their was a vac. advance and I didn't see one.
What I remember is that there are 2 groups of wires coming out of it which go to 2 separate connectors if it's the ECU controlled one. Easy way to determine if it's your problem is to connect a strobe to no. 1 plug & run the engine at idle while watching the timing mark under the strobe light. Get somebody to slowly increase the revs & you should see the timing mark (on the damper) move as the revs are increased & decreased. If the mark stays where it is then there's no automatic advance, probably due to having the wrong dist fitted, or the right one not connected up correctly. If there's no advance then the car will run like a dog. If you need a dist then you may be able to pick one up on this forum?
Thanks for you long and informative post, and how did my car get in the UK? Yours looks exactly like mine in your sig pic!
I'm going to take my car in to a chevy mechanic (he's old and new school) and has his own shop, while working full time for a local chevy dealer. As suggested, after getting the distrib./carb/tuning problem out of the way (with or without ECM - which I prefer not to have), I think I'm going the header/true dual exhaust route while dropping the cat completely. After looking over everything, It really doesn't look to difficult a job adding the headers.....I AIN'T SCARED!!
The Dynomax Headers I fitted were easy to get on. I put them in from underneath & to make it easier I had the trans mount removed (only 2 bolts on the x-member). I then put a floor jack under the trans & lifted it very slightly, tilting the engine forwards, so that the Heders could slip right in easily. Apparently they can be wiggled into place with patience, but I was running short of patience at the time
The only tricky thing I found with Headers was hooking them up to the original system. I got around that by making a system up from scratch, but any good exhaust shop should be able to sort something out for you. Getting 2 1/2" pipes bent was a problem for me as very few vehicles here use that size of pipe. The ones that do just fit "off the shelf" replacements so I had to go to an F1 car exhaust manufacturer to get mine bent. Then I saw the exhaust bending machine on American Hotrod & wept Good luck getting it running right. Once it's running as it should, & you've got dual pipes on it, you should be a lot happier with it
Then, after about a week, you'll be wanting even more power.......
02-17-2005, 01:02 PM
#55
CFOT Attention Whore
paul and MsVetteMan, this is how to tell if your distributor is ECM controlled... look on the back of the distributor, between the cap and the firewall. if there is a four wire plug coming off it and there is no vacuum advance canister on the front/right side, it's ECM controlled. another way, if your still just really not sure, is pull the cap and rotor off. the module that controls dwell and advance is a seven-pin type. 2 on one side and 5 on the other. after that, if your still not sure, sell your car and go buy a freakin' hyundai and some 'type R' stickers. 
for the time being, if the computer system is whole and connected, i think you would be dollars ahead reconnecting the system. the computer can support what you want to do for now. just make sure you have an O2 sensor welded into your new exhaust. once you start looking for 400+hp, then scrap the computer.
now, let's see if you have the computer hooked up. first step: does the 'check engine' light come on breifly when you start the car?
next step: turn the key to the 'on' position but do not start the car. remove the ashtray and look down underneath. you will see a five pin connector. take a paperclip or piece of wire with the ends stripped off and connect the two pins that have the notch missing between the them. if the computer is hooked up, you will hear the idle mixture solenoid cycling (real fast "tick, tick, tick..." from under the hood). if every thing is working correctly, you will see the check engine light flash a test code, 12 (once, short pause, twice, long pause, and repeat two more times). it will do that 3 times. if there are any stored fault codes, it will flash each of them 3 times, and will follow up with the 12 code again.
try that and let us know what, if anything, comes up.
for the time being, if the computer system is whole and connected, i think you would be dollars ahead reconnecting the system. the computer can support what you want to do for now. just make sure you have an O2 sensor welded into your new exhaust. once you start looking for 400+hp, then scrap the computer.
now, let's see if you have the computer hooked up.
first step: does the 'check engine' light come on breifly when you start the car?next step: turn the key to the 'on' position but do not start the car. remove the ashtray and look down underneath. you will see a five pin connector. take a paperclip or piece of wire with the ends stripped off and connect the two pins that have the notch missing between the them. if the computer is hooked up, you will hear the idle mixture solenoid cycling (real fast "tick, tick, tick..." from under the hood). if every thing is working correctly, you will see the check engine light flash a test code, 12 (once, short pause, twice, long pause, and repeat two more times). it will do that 3 times. if there are any stored fault codes, it will flash each of them 3 times, and will follow up with the 12 code again.
try that and let us know what, if anything, comes up.
02-17-2005, 01:31 PM
#56
Drifting
There's a lot of usefull information here, but in my opinion Gator81 had the right idea.
I also have an 81 that I am looking to add more performance to. I am more concerned with cornering ability though, than with power though.
My 81 is an all original very low mile car that is in really great shape, but is is a 24 year old car after all. I am starting with the most basic components and going from there. I won't even think about motor work at this point.
My point is if I were you I would get the car back to (or as close to) 100% stock condition, then go from there. It's like a house, you wouldn't build it on a bad foundation. That extra HP is going to be no fun if you can't stop or turn correctly.
I also have an 81 that I am looking to add more performance to. I am more concerned with cornering ability though, than with power though.
My 81 is an all original very low mile car that is in really great shape, but is is a 24 year old car after all. I am starting with the most basic components and going from there. I won't even think about motor work at this point.
My point is if I were you I would get the car back to (or as close to) 100% stock condition, then go from there. It's like a house, you wouldn't build it on a bad foundation. That extra HP is going to be no fun if you can't stop or turn correctly.
02-17-2005, 01:33 PM
#57
Hi Clutchdust,
Refresh my memory: the two groups of wires from the ECU controlled dist are the 4 you talked about & also another group of 3? And where can I get these stickers you suggested? I hear they're good for another 50bhp
I'm with you on this in that it'd be cheaper to connect the computer back up, assuming that everything is still in place & working. Any problems with the car can, in all likelyhood, be solved by checking out the error codes as you described (a BIG advantage of the computer). But if the carb has been swapped out, the computer fried or the wiring butchered by the previous "mechanic" then it could start getting problematic (if the guy couldn't get it to run properly & his solution was to disconnect the dist from the computer controlling it, as it sounds like, then anything could have been done to it!). Hopefully the mechanic that will be looking at it will sort it all out, one way or the other.
Refresh my memory: the two groups of wires from the ECU controlled dist are the 4 you talked about & also another group of 3? And where can I get these stickers you suggested? I hear they're good for another 50bhp
I'm with you on this in that it'd be cheaper to connect the computer back up, assuming that everything is still in place & working. Any problems with the car can, in all likelyhood, be solved by checking out the error codes as you described (a BIG advantage of the computer). But if the carb has been swapped out, the computer fried or the wiring butchered by the previous "mechanic" then it could start getting problematic (if the guy couldn't get it to run properly & his solution was to disconnect the dist from the computer controlling it, as it sounds like, then anything could have been done to it!). Hopefully the mechanic that will be looking at it will sort it all out, one way or the other.
02-17-2005, 02:30 PM
#58
Melting Slicks
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I just checked....There are indeed four wires coming out of the distrib. about 4 inches or so from the top and going towards the firewall. I didn't see a vac. advance. The engine light does not come on when I turn the key, or when starting, or after. I tried the clip trick, and heard, or saw nothing.
Amazing how car is even running the way it is. On a scale of 1 to 10 with 10 being best, I give it a 7 the way it is now. You would think of the former "bubba" could get it running like this (and it's probably temporary, I'm sure) then he could have at least got it running with the ECM hooked up.
Anyway....thanks, and I'm hooking up with my mechanic on Wed.....lol, I feel like I made a doctors appointment.
I'll let ya know what happens....
Amazing how car is even running the way it is. On a scale of 1 to 10 with 10 being best, I give it a 7 the way it is now. You would think of the former "bubba" could get it running like this (and it's probably temporary, I'm sure) then he could have at least got it running with the ECM hooked up.
Anyway....thanks, and I'm hooking up with my mechanic on Wed.....lol, I feel like I made a doctors appointment.
I'll let ya know what happens....
02-18-2005, 12:54 PM
#59
CFOT Attention Whore
paul, that 3 pin should go up to the coil. it sits behind the power in and tach plugs.
MS, first, i'd advise you to check the computer (as described above) and make sure that it's even connected.
as long as the wiring is not butchered, you might consider just getting a replacement computer. figure $100-150 for an exchange unit as opposed to $200 for a distributor and $300-400 for a new carb. throw in a new O2 sensor ~$25, and for under $200 the car should be in much better shape.
the reason it works as it does now is because the engineers designed in a "limp" mode that the distributor timing faults to a basic setting and the carb will still work to some degree, just to get you home.
now you need to verify that the carb is a computer carb. pull the air cleaner and you will see a two wire plug on the front right top that points off toward the pass. side engine vent. that's for the mixture control solenoid. if it's there, you still have the computer carb. i'd bet it's there but no signs of a plug going to it. find that plug and also check to see the throttle position sensor is still connected (3 pin plug on the left front of the carb). make sure the computer fuse is not blown. (yeah, the fuse block in our cars
)
if you have a computer carb and computer distributor (caveat: so long as the wiring harness isn't butchered), it would be easier and cheaper for you to reconnect the computer even if the ECM is bad. you may get lucky and find that disconnecting the computer may really mean they simply disconnected the two plugs to the computer. *crossfingers*
MS, first, i'd advise you to check the computer (as described above) and make sure that it's even connected.
as long as the wiring is not butchered, you might consider just getting a replacement computer. figure $100-150 for an exchange unit as opposed to $200 for a distributor and $300-400 for a new carb. throw in a new O2 sensor ~$25, and for under $200 the car should be in much better shape.
the reason it works as it does now is because the engineers designed in a "limp" mode that the distributor timing faults to a basic setting and the carb will still work to some degree, just to get you home.
now you need to verify that the carb is a computer carb. pull the air cleaner and you will see a two wire plug on the front right top that points off toward the pass. side engine vent. that's for the mixture control solenoid. if it's there, you still have the computer carb. i'd bet it's there but no signs of a plug going to it. find that plug and also check to see the throttle position sensor is still connected (3 pin plug on the left front of the carb). make sure the computer fuse is not blown. (yeah, the fuse block in our cars
)if you have a computer carb and computer distributor (caveat: so long as the wiring harness isn't butchered), it would be easier and cheaper for you to reconnect the computer even if the ECM is bad. you may get lucky and find that disconnecting the computer may really mean they simply disconnected the two plugs to the computer. *crossfingers*