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Re: 1988 Pontiac Trans Am getting the LS treatment
Originally Posted by alex722607
Thanks for the compliment. Virtually anyone that knows anything about an internal combustion engine can do this. But it certainly helps when your dad is next to you giving you pointers.
It's not a matter of knowledge or capability, it's more of a time/place/motivation lol. After work I'm usually busy or wiped. I'd love to see a video!
Re: 1988 Pontiac Trans Am getting the LS treatment
Yeah that's a big one. I planned for this 3 months beforehand, and had 1 month to do the big stuff. Patience literally got me going stir crazy, but I kept remebering that breaking down every two weeks and sucky gas mileage was a bigger headache.
Re: 1988 Pontiac Trans Am getting the LS treatment
a big part of my problems stemmed from bad grounds, terrible power distribution, broken connectors, a previous engine swap that had problems from day one, and the list goes on (also a bad distributor cap..............
Re: 1988 Pontiac Trans Am getting the LS treatment
Wow thanks for these. I think I am gonna start accumulating parts and will probably tackle this in the summer. For now this car needs to return to driver duty...lol as soon as the snow threat goes away
But yeah I know exactly what you mean about the rear suspension. I always heard these creaks and moans and it makes sense that it would be the weak construction of the rear end. (I am just grateful I have a 9 bolt)
Re: 1988 Pontiac Trans Am getting the LS treatment
Yeah, I bought all mine at once. It was a bit of a sticker shock, but I was deployed at the time so what else was I going to spend my money on. There are more expensive parts out there, but they don't function any better than what I listed. The good part is that you can get those one at a time and put them on as your budget allows. First I'd do the control arms and relocation brackets, then the SFC (and weld them in once they are bolted in place), the panhard bar, and then finally the torque arm.
Re: 1988 Pontiac Trans Am getting the LS treatment
I sent him the link for an adjustable panhard bar, but get the single adjustable ones. The on car adjustable is over kill and more threaded parts to fail.
These are the only adjustable ones that I would spend money on. I have the poly/roto-joint non-adjustable ones, which don't seem to be available anymore.
Re: 1988 Pontiac Trans Am getting the LS treatment
Yea when I start getting parts I am gonna ask a ton of questions. As for lowering the car, I dont think I can lower it any at the moment simply because of the exhaust.
Right now I need to get myself a door hinge kit for my drivers door and I need new latches, because mine are shot. To the point I have real trouble closing the doors and with the sag and window alignment, it makes it worse.
Anyone know if I should get the same hinge kit dorman offers for both the upper and lower on the drivers door?
Re: 1988 Pontiac Trans Am getting the LS treatment
The on car adjustable PHB makes it much easier to make adjustments. There really inst anything more to "fail" over a single. May as well go with non-adjustable
Re: 1988 Pontiac Trans Am getting the LS treatment
I know the conversation is flowing in terms of suspension, but I need to do a redirect, cause I need the input of wisdom. I looked for rerplacement door latches and literally I only found used and new repro's from classic industries.
Well I have a small box full of 4th gen door stuff, including a latch and striker. When comparing the mechanism's action over the 3rd gen stuff, the 4th gen one is much smoother. So I am gonna ask the question, would it be possible to adapt the 4th gen stuff to work on our doors? The holes are different, but that is a matter of drilling new ones I would think. The latch is different too This is something I would like to try to get away with, without a repaint in those areas. I know I am asking a lot, but anyone heard of this. I searched, but only found negativity on the subject, and nothing helpful
With that said, any takers to answering this question
Re: 1988 Pontiac Trans Am getting the LS treatment
Originally Posted by scooter
The on car adjustable PHB makes it much easier to make adjustments. There really inst anything more to "fail" over a single. May as well go with non-adjustable
I was referring more about the control arms than the panhard bar. When I did mine, I picked up the single adjustable one and it really wasn't that bad. I eyeballed it and when I had a 4 wheel alignment done and it was spot on.
Originally Posted by alex722607
I know the conversation is flowing in terms of suspension, but I need to do a redirect, cause I need the input of wisdom. I looked for rerplacement door latches and literally I only found used and new repro's from classic industries.
Well I have a small box full of 4th gen door stuff, including a latch and striker. When comparing the mechanism's action over the 3rd gen stuff, the 4th gen one is much smoother. So I am gonna ask the question, would it be possible to adapt the 4th gen stuff to work on our doors? The holes are different, but that is a matter of drilling new ones I would think. The latch is different too This is something I would like to try to get away with, without a repaint in those areas. I know I am asking a lot, but anyone heard of this. I searched, but only found negativity on the subject, and nothing helpful
With that said, any takers to answering this question
Replace your pins and bushings. Not hard if you use the door spring removal tool, last I checked they were available for rent at Autozone.
One per door. Use this code when you pay: 2931659926937035.
I just got a 5% discount code in my email today, and I don't plan on using it. Someone may as well.
Re: 1988 Pontiac Trans Am getting the LS treatment
Originally Posted by alex722607
Well I have a small box full of 4th gen door stuff, including a latch and striker. When comparing the mechanism's action over the 3rd gen stuff, the 4th gen one is much smoother. So I am gonna ask the question, would it be possible to adapt the 4th gen stuff to work on our doors?
I contemplated this too at one point, but I think it is a bit more complicated than just drilling some holes. I think you would need to re-engineer the latch area at that spot of the door. If you got em, smoke em....
Re: 1988 Pontiac Trans Am getting the LS treatment
Originally Posted by khulsebus
I was referring more about the control arms than the panhard bar. When I did mine, I picked up the single adjustable one and it really wasn't that bad. I eyeballed it and when I had a 4 wheel alignment done and it was spot on.
Replace your pins and bushings. Not hard if you use the door spring removal tool, last I checked they were available for rent at Autozone.
One per door. Use this code when you pay: 2931659926937035.
I just got a 5% discount code in my email today, and I don't plan on using it. Someone may as well.
Thanks for the code, I actually got one in my email too that I am gonna use. So thanks anyway!
Re: 1988 Pontiac Trans Am getting the LS treatment
Got the door hinge components, have yet to install them though. I also got new wiper transmission casing bushings. I encountered a wacky problem with the wipers in that when they pause, they do so quite high on the windshield. It has me stumped.
I also got the HID kit for 82-90 firebirds that is available through DDM Tuning. Fits nicely.
Re: 1988 Pontiac Trans Am getting the LS treatment
Today I stripped my jasper 350 just because. I got some compression readings from it... Cylinder 1 and Cylinder 7 were both below 100 psi, the rest were between 150 and 175 psi. I also discovered I have a 638 casting block, and 193 heads. (wrong heads for a stock B2L) I think its a caprice motor - thats where it probably started its life and the cam is probably also wrong for my old tune aswell. Well so much for that leaky old motor.
I ve been having lots of fun driving my car with my new powerplant.
**and I also got under 50 psi for cylinder 6 and both head gaskets were about to blow - btwn cyl. no. 3&5 and 4&6 also, major scoring of the walls and no corsshatching at all.
Last edited by alex722607; 03-25-2015 at 11:04 AM.
Re: 1988 Pontiac Trans Am getting the LS treatment
I have a bit of a problem. For starters, my fuel mileage has dropped and i suspect its the injectors or an exhaust leak. I am getting 14.5 combined city/highway. I previously ran on 87, now I just tanked up with 89. This I noticed shortly after I unkowingly almost ran it out of gas. Basically i have not gotten adjusted to my new fuel gauge - when its at 1/4 tank - it has about 1.5 gallons left (16.9 gallon tank) I put fuel system cleaner in with the gas. The injectors I got came with the intake and may have sat for a while - thing is she starts up fine.
Also problem two is I think something is wrong with my gear selector- I cant get it into park and when I do its only for a short while as it jumps back into reverse- I think the alignment is off and the console mount could be messing it up. I think I have to pull the console again.
Need help with the fuel issue though. - thinking I should contact southbay and have them flowtested
Re: 1988 Pontiac Trans Am getting the LS treatment
Might be best to do a flow test. Running rich? Could be a combination of things, honestly. If it starts up fine, and the injectors flow fine then your tune might be dumping too much. Way too many variables to pinpoint off a post.
Re: 1988 Pontiac Trans Am getting the LS treatment
that could be it as now that i think of it When my dad drove it a couple days ago he said he saw black smoke coming out of the tail pipe - its a mail order tune, so it does make sense. Guess I gotta do the trouble tree, and if it all checks out- i have to get it dyno tuned cause 14 is ridiculous- especially for a 5.3 in a light car as this. Thing is it was pretty good until I ran it low on gas (low meaning enough to stall it up a small hill)
Re: 1988 Pontiac Trans Am getting the LS treatment
I just thought of something- could the fact that i reused the old catalytic converter have something to do with it. I mean- the old 350 was burning a lot of oil which cant be good
Re: 1988 Pontiac Trans Am getting the LS treatment
That could have an adverse effect, for sure. Burning oil = clogged up Cat. I cut my old 305 cat off after it got clogged up and it made a huge difference. Have no desire to go through anything like it again so there will not be any Cat's installed once I finish my build.
Mail order tunes can only go so far. I highly recommend getting it looked at ASAP. I look at them as an advanced form of limp mode, lol. Great for testing and getting a feel for things, but they are limited.
Re: 1988 Pontiac Trans Am getting the LS treatment
First thing, get it tuned. I took mine my tuner did a street tune, and it picked up a ton. Then we went to the track and he tightened up the tune a little more. That mail order tune is basically a bunch of guessing to get it close enough.
Second, how are you running 87 or 89 octane. Before mine got tuned, I'd get a check engine light if I even thought about putting 87 in it. My dad did it on accident, and it took 4-5 full tanks of 93 to get it all out and stop throwing the code for engine knock. Basically once the code got thrown, it would pull timing and power and mileage would suffer. Even if the light isn't coming on, I wouldn't be surprised if the code isn't there.
Lastly, you probably burnt your shifter cable. I went to drive mine one day and I couldn't hit park or low gear anymore, and it felt a little more mushy than normal. I checked out the selector on the side of the trans with the cable disconnected, it shifted fine by hand. I checked out the shifter with cable disconnected, it shifted normally. I grabbed the cable and it felt like s***. This is the second time I broke a cable, when I blew up the trans last year, the shop said the cable was bad and needed to be replaced.
I ordered a new cable from rock auto, and then wrapped it in heat protective sleeve from Summit. The whole cable is covered, from the little grommet where it enters the tunnel all the way to the lever on the side of the trans. So far it's worked.
Re: 1988 Pontiac Trans Am getting the LS treatment
Actually my exhaust runs similar to the stock routing for the sbc. I need to take more pics of it.
I figured out my problems I think. Number 1- the gas mileage is two fold - i have an exhaust leak at the manifold because the bolt by the number 8 cylinder - well I couldn't get to it and did not have a box wrench to tighten it so its just there by hand which I completely forgot about. Number 2 is the tune. I have to fix one problem to work on the tune though.
Get this on the trans- the cable is new and its perfectly fine, the selector on the trans got loose. So I drained the fluid and dropped the pan. The gear that rides on the leaf spring is held in by a nut. That nut got loose and the gear slipped the leaf spring and stopped doing anything all together.
I need to tighten that exhaust manifold and check my fuel trims again, because they were reading -2 on left bank and +18 on the right bank (at idle) I am also getting new intake gaskets - just because I got gaskets with the intake and never replaced them. With any luck it should take about 45 minutes for everything.
Re: 1988 Pontiac Trans Am getting the LS treatment
Well so far everything is okay with the engine except for a couple snags I recently hit... So without further ado here we go.
I fixed my exhaust leak which was in two places. One was at the cat just after it which was because of the mating being crushed. I bought a new flange mating surface from summit and finally got around to modify it to fit. It only has a minor leak at the at point now- keep in mind it's only held on by being pushed together, it's not welded or anything- it sort of slipped inside. The other leak was at the pipe that goes over the axle and was because the slip fit was messed up. So I cut it off and replaced it. Seems my dad had a problem with that years back when he replaced the TPI fuel pump and had to drop the exhaust.
Lately I have been getting shitty fuel mileage and a running lean code- yet it's running way rich. I can see black smoke when I hit the gas. Also at around 50 mph when I hit the gas I feel a stumble which only corrects if I hit the gas a lot more. I am getting an error code po171 which is running lean.
Re: 1988 Pontiac Trans Am getting the LS treatment
If the ECM thinks it's running lean it will dump in a lot of fuel to try and correct it. That would be your black smoke issues. I've run into contaminated oxygen sensors that cause really weird fuel trims. Just a suggestion if you've eliminated any other possible causes.
Did you replace the intake gasket?
All of this is based on trucks with 5.3's, same principle should apply though. Hope I maybe helped.
Re: 1988 Pontiac Trans Am getting the LS treatment
Okay thx I'm gonna add that to he list. So what I will be doing is the following:
I will be replacing the intake manifold gaskets and the throttle body gasket as soon as they come in as they could be repsonsible for a vacuum leak causing this issue. In addition i suspect a faulty injector or two because when I connected it to the scan tool, and manually **** off each injector one at a time and noted any differences, on a couple there were absolutely no changes to how it ran. Now truth be told the exam will correct they condition to a degree, but the car will run weird for the time it takes for the ecm to correct or compensate.
afterwards I will examine the left upstream O2 sensor because it could be getting a false reading due to the wires for it being tight up against the crossmember.
Hopefully I'll do injectors tonight and gaskets when they come in. I also need to take it in for a wheel alignment because I don't wanna be dishing out for new tires
Re: 1988 Pontiac Trans Am getting the LS treatment
Okay so today I completed phase 1 - I replaced the fuel injectors with replacements from Southbay. The old ones had some rust spots where the fuel sprays out of which alarmed me. I sprayed carb cleaner throughout the fuel rail, and everything is fine. I put the new ones in and drove it about 5 miles or so, including highway and - wow what an improvement in throttle response and the hesitation at 50 mph is gone. I am still going to relocate that O2 sensor and replace the intake gaskets and throttle body gasket.
Re: 1988 Pontiac Trans Am getting the LS treatment
I have yet to see. I can't plug it in right now because the car is going in for a wheel alignment this morning. But I should get it back this afternoon so well see then.
Re: 1988 Pontiac Trans Am getting the LS treatment
I plugged in yesterday and I still got weird fuel trims- 25 on 1 .....and 9 on 2.
I suspect vacuum leak and/or kinked O2 sensor wiring due to placement of said sensor.
On a side note I blew out my tire yesterday. -pretty well too... Sidewall is gone.
It didn't hit me till this morning as yesterday when it happened it sounded like it was the differential making noise. I mean the whole time you think it's much worse than it is. Even though a blown tire is still pretty bad. Hopefully it's covered by the warranty. And since I have to get two- because who replaces just one tire - now my firebird rim will have a tire on it so I will have a spare again.
So I am trying to look at the bright side. And another thing is that now I will have the time to put a/c back in and fiddle with a couple things. The downside is that if it is not covered by the warranty - then I just blew the money I had put away to buy new seals again.
Re: 1988 Pontiac Trans Am getting the LS treatment
A vacuum leak should affect both banks in terms of fuel trim you would think. Even an intake leak SHOULD impact both banks. I would still be suspicious of that banks O2 sensor 1. I have also seen MAF sensors do really weird things. Either way, I hope you can track down your issue! Keep us posted!
Re: 1988 Pontiac Trans Am getting the LS treatment
So something very interesting happened yesterday. I was about to get on the highway and suddenly the SES light came on. I noticed that from stop it would not start rolling while in drive. I brought it home and discovered a bunch of codes and the engine sensors fuse blown. Codes were as follows:
P0102
P0740
P0753
P0785
P01860
P0171
Naturally I though that the 02 sensor that we were talking about finally the wire was cut through due to the positioning of the sensor and it grounded against something blowing the fuse. I disconnected the 02 and replaced the fuse. - it happened again
Re: 1988 Pontiac Trans Am getting the LS treatment
Well my diagnosis was all wrong.
It was the wiring harness being cooked by the exhaust manifold.
When I taped up the harness with foil tape I missed an entire section of trans wires and they essentially melted.
I ended up removing the entire harness and cutting out bad sections, soldering and shrink tubing it together.
I just got finished putting it back in and its fine now.
One problem area is around the starter. I went back together tight and I am not happy about that. When I muster the strength to do so I will revisit that and see what I can do to remedy that.
Now I just have to finish the a/c install and take a look at a leaking tranny cooler line.
Re: 1988 Pontiac Trans Am getting the LS treatment
Originally Posted by alex722607
Well my diagnosis was all wrong.
It was the wiring harness being cooked by the exhaust manifold.
When I taped up the harness with foil tape I missed an entire section of trans wires and they essentially melted.
I ended up removing the entire harness and cutting out bad sections, soldering and shrink tubing it together.
I just got finished putting it back in and its fine now.
One problem area is around the starter. I went back together tight and I am not happy about that. When I muster the strength to do so I will revisit that and see what I can do to remedy that.
Now I just have to finish the a/c install and take a look at a leaking tranny cooler line.
I'll take pictures after I wash it.
Yeah, a melted wiring harness would definitely do that haha. How close did you have to run the harness to your manifolds? Is there any way to get it far away? What circuits are in that part of the harness? Glad you found the problem!
Re: 1988 Pontiac Trans Am getting the LS treatment
When I built the harness I essentially kept everything the harness came with, with the omission of evap, air, egr and so on. Everyhting else stayed factory 4th gen.
The way it is, the trans, maf, H2OS are all fed by the ENGINE Sensors fuse.
The trans wires and speedo wires ran from the computer, down right front strut tower, parellel with the manifold. It then ran along the frame rail to the trans. I kept it in place with a fuel line clip and secured it to where the old evap line was secured. I then ran the downstream H2OS the similar way. I ran the crank wires seperate from the oil level wires (which now is combined) direct from the computer to the sensor behind the starter, on the outside of the manifold. Being that it is on the outside, when it gets under the manifold, it has to make a 90 degree turn and it hugs the manifold all the way to the starter.
I am not happy in the least about this. The way I see it is that if I run it between the manifold and the block it might be better. And there is foil tape on it, but I am not sure if that is where I want to put it. (But I dont have many options.
The other problem is that I also had to wrap the battery wire and the ignition wire for the starter in the foil tape as they come really close to the manifold. They in fact touch the heat shield. They too have to make that 90 degree turn under the manifold and are pressed in place when the starter is mounted. The problem I dont like is that it is tight, the wires, albeit are wrapped in foil tape, they are pressed against the manifold. Also the foil tape conducts electricity, so if it touches a hot to an ign power source, that starter will spin and wont stop, or something will short out. This is the worst I can think of that can happen, but it also might not. Thing is I can't see how close everything is up where it is mounted, but just the fact that it is tight, I don't like it.
And now that i am writing this, I don't like it even more. I am really considering running the wires between the manifold and the block, just because they won't be pressed against the manifold. And they have foil tape on them anyway, so the wires should be fine.
Re: 1988 Pontiac Trans Am getting the LS treatment
Yeah, tight is no good (well, at least when it comes to wiring haha) Do you think it would be worth it to make them longer and, although running a lot longer way, run them along the strut tower and down to keep them away from the engine until they need to be on the engine? Or, and again, I'm referencing a 5.3, but is there not a few studs holding the coil packs onto the valve covers? If so, run the wiring there then down along the fire wall? I'm just spit ballin' here so please feel free to tell me if those ideas would not work.
Re: 1988 Pontiac Trans Am getting the LS treatment
yea making them longer was my first thought, the only problem I still see is that it has to still go under the manifold and make the 90 degree turn. Tomorrow I am gonna pull the starter down again and try to reroute it and report back. Also I will make sure to take pics ...finally
Re: 1988 Pontiac Trans Am getting the LS treatment
Well , I was able to rerout the wires, so now none are tight against the manifold. I ran oil level and crank next to the dipstick.
I ran the starter wires in front of the cross member and next to the engine mount so that they travel to starter horizontally. The only problem I ran into is that one of the studs for the starter ended up stripping somehow ?? so I removed it to try to repair it. I removed the solenoid thinking that I could replace the stud, turns out that the solenoid doesn't come apart. I did end up screwing up the screws that hold the solenoid to the starter, so I need to replace those. My dad did tap the stud that stripped, but there is missing metal, so I need a new one, it will work for now, but I don't feel comfortable leaving it like this. Only a couple threads engage nut and I cant use washers.
Also I need to remove the right side exhaust manifold so that I can reroute the tranny cooler lines away from it. They lean against it.
Re: 1988 Pontiac Trans Am getting the LS treatment
that last picture shows the previous routing of the wires somewhat.
Also the welds look horrible, but they don't leak, I have to revisit this one day, perhaps I will have it proffessionally done and have headers, but keep in mind, this was built for under like 150 bucks.
also the rear O2's I am planning on revisiting when I fix the tranny cooler lines - just need to get the motivation and time.
Also A/C may look complete, but its not, it will be though ...soon
Re: 1988 Pontiac Trans Am getting the LS treatment
Atta boy! I think it looks good. And don't even worry about some of those things. You got it in and running so call that a win. The other stuff is just minor 'touch up' things. Glad to hear you routed the wiring a little better, tough luck about the starter. Keep at 'er!
Re: 1988 Pontiac Trans Am getting the LS treatment
Well since I havent updated this since May, I might as well get everyone up to speed. So first I decided to install the a/c compressor, it was a pain in the ***. Note: if your are gonna run A/C install the bracket and compressor on the engine before it goes into the car.
The main problem I have been having with the car is the paint. It is peeling left and right. Unfortunatly I have not had the time to take it to the bodyshop that did the paint. That is coming soon however. Lately I have been working on the exhaust. I had a never ending leak at the manifold flange that it kept cooking my harness.
I got racing innovation headers and a hawks conversion y-pipe. I welded a cat after the y-pipe and am installing an OBX catback I got from Hawks as well. Its for a 4th gen but its gonna work just fine. Good thing I decided to do the exhaust cause when I pulled the old crap down, I noticed that the stock cat, well the insides came apart and a little more and I would have had pieces of catalytic converter in the engine.
The passenger side header required the removal of the engine - it was a pain in the ***. I also had to reroute the fuel line and I had to route the brake line through the frame rail. After I am completely happy with the exhaust, I am going to get a tune, and back to paint she goes. It is really embarrassing because it is peeling just about everywhere, probably **** poor prep work.
Some other stuff i have done:
I replaced the stock steering shaft, both the column and the intermediate. The column came from a 2002 camaro/firebird, and the intermediate is from an astro van. I needed to replace the column cause my steering wheel controls went nuts and started to do silly things to the radio when I turned the wheel. Then it fried my control pad and that was the end of that. Since you cant find the cam for this column, I replaced the entire thing. Besides I like the SIR coil thing better, and the astro intermediate shaft looks WAY better than the stock 3rd gen one. (and requires no modification when used with a 4th gen column)
I also went with a monsoon radio and 4th gen wheel, cause my 3rd gen control pad was fried and I had the 4th gen stuff lying around.... so why not (its a better radio and looks stock anyway)
03-02-2015, 07:06 PM
