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Discussion Starter #1 (Edited)
Good Day All,

Before you 馃敟 me for asking about engine upgrades, please read on...then if you feel needed, flame on.

1st, I have read through the following thread and many like it on this forum, great information but I am quite ignorant to engines. I have tried my best to understand and help myself, but would like some input:
LT1 Camshaft/Valve Train Selection Guide

Here is my situation:
I have a 1996 Roadmaster Wagon (LT1) that I purchased in 2017 and have not done much with it. This fall/winter I originally intended to upgrade the suspension to QA1 Coilovers and replace the steering components and upgrade the stereo. Well, the project has snowballed. As I remove things, I find things easier to get to and figure "while I am in here". There are several things that I am working on, which is leading to pulling the engine and trans to have the trans rebuilt/upgraded and I have a rear main seal leak and possibly a front one as well.

Since the engine is out, I am wondering if there are any maintenance or upgrades that I should consider, car has around 118K on the clock. Here is more information to help with suggestions.

Below are some drivetrain things that have been or are being done:
The car currently has the Bailey LTCC Setup for ignition, link below:
Bailey LTCC setup
I will be adding GenII Try-Y Headers with High Flow Cats and a SSRI from Clear Image Automotive
Car has 2.5" exhaust
Intend to rebuild the rear with 3.42 gears and Posi

Would I need to change out the torque converter?

The car is already fairly quick, but looking to improve on that. This car will not be tracked, so I am not looking for the fastest 1/4 mile. I may run it on a track for fun or an AutoX with a local car club, but nothing for competition purposes, just fun.

The main intention of this car is to be a fun cruiser along with an enjoyable to drive road trip vehicle. Ideally I want it to somewhat be a sleeper, something that can surprise people on a cruise or at a light, but not something with a loping idle or loud at idle. I don't really need more high speed performance, additional torque and low to mid range power I think would be most beneficial, again, not going for top speed, just quick off the line and great passing power. This is why I am looking for guidance, much of the information I see tends to be race related.

Any questions, let me know.

Thanks in advance for any help and guidance....hopefully I am not deserving of a flaming for this post.
-Dan
 

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The more torque and low end part , has me wondering if maybe keep the stock cam and put 1.6 rockers and call it a day ?

My LT1 , I had the baby Comp 304 , Even it lost some sub 2000 rpm power.

Convertor , The vigilante 2600 9.5 lock up ( again personal experience) was a great convertor
 

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Prefer 3.73 gears... Other than that, I think you have a solid plan.
 
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Swap the cam while the engine is out. Even with a "baby" cam, it will still be an upgrade over stock. Since you are swapping gears and converter it will still feel stronger than stock, even low in the powerband.
 

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Discussion Starter #6
Hi All, I figured since I haven't replied yet, I would just quote each of you and reply in one post vs several different posts.

The more torque and low end part , has me wondering if maybe keep the stock cam and put 1.6 rockers and call it a day ?

My LT1 , I had the baby Comp 304 , Even it lost some sub 2000 rpm power.

Convertor , The vigilante 2600 9.5 lock up ( again personal experience) was a great convertor
@95wagon - After your comment, I did edit my post to indicate low and mid-range. I am looking for performance beyond off the line, but not looking to gain top speed. I would still like to have good torque and power when passing on the highway or interstate. When I stomp on it, I want to go, even if I am rolling. Not certain if this changes your statement. With the gear change and upgrades, do you believe the TC change out is beneficial? I have tried to comprehend the way the TCs work, but just cannot seem to grasp it. I learn best either hands on or through clear data...kind of a "numbers" guy, however the visual of YouTube videos has worked great for my learning curve on some things.

Prefer 3.73 gears... Other than that, I think you have a solid plan.
@1slow96 - Thanks, however I am looking for any suggestions or maintenance items that I should consider while my engine and trans are out. Regarding gearing, see my next reply below to 95 wagon.

Wait until you find out he is going to run 28.6 tall tires馃
PREFER may be too soft a word .
@95wagon & @1slow96 , as noted above in my post to 95wagon, I don't fully comprehend things until I can get the information in a format my brain will accept, I believe most of us are that way but the "way" we understand the info is different. I was starting to feel a little flaming here, I can take it, no problem. So, I had to do some digging to understand why a larger tire would make a difference regarding gearing...yeah, I am that basic. So much of the information on these forums is opinion, which is fine, but as I have debated about gearing, originally thinking 3.08 and being coaxed and convinced to step up to at least 3.42 I accepted that as I also want to keep decent MPG for road trips.

I found the chart in the following link with a screen shot below based on 1:1For some reason, my little mind could understand this. I guess because it is actual data presented. If I want to be in the best daily driver range I will either have to step down in tire size (was debating about a 27.6" size before thinking a larger tire would look better) or upgrade gears, otherwise I will be riding on the edge of MPG and daily driver, which might not be too awful
Gear Ratio Chart | Revolution Gear & Axle
198144


Swap the cam while the engine is out. Even with a "baby" cam, it will still be an upgrade over stock. Since you are swapping gears and converter it will still feel stronger than stock, even low in the powerband.
@94SSman - what is considered a "baby" cam for our LT1s? I am not solid on swapping the converter, but it would be one less thing that I have to worry about failing and replacing later. Again, "while I am in here" allows me to make sure I have a fun, solid running road trip cruiser when complete.
 

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On an old LT1, tight budget, Comp Cams UltraPro Magnum 1.6 Roller Rocker Arms, reprogram for 91 or 93, done.

On a comfortable budget, ask Advanced Induction, Lloyd Elliott, or Karl Ellwein about a cam that works well with OEM iron heads, loses no low end, and makes more power to / WOT-upshifts by 6000RpM.
They'll tell you which rockers to use, 1.5 or 1.6 (or maybe both!)

On a very comfortable budget, make all these people scratch their heads and trade the LT1 intake manifold for a
FIRST Fuel Injection Tuned Port Intake Manifold
because you're far more into road-tripping a [email protected]$$ wagon with your family hauling a buttload of stuff.
You're not racing for glory like all these others who suggest a cam and/or heads that will 'move the powerband further to the right'.

Also why I recommend 3.42 over 3.73. (In 26 years no one ever came out with a 3.5x rear end and reluctor for us, FOR FOCH'S SAKE!?)
If there's enough weight in the wagon, only thing wrong with 3.73, is that there's no way to know if your driveshaft will impersonate a guitar string at 80something MpH. Maybe the ISSF can fund a kickstarter to buy you a driveshaft upgrade?
If not, 3.42.

If you upgrade the torque converter, tell them you're probably gonna fill the wagon with people and stuff!
If you upgrade the torque converter, upgrading your ATF cooler is a MUST.
At least add a damn fan to it! - but best to get a better cooler AND put it in a better spot.
 
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I was not intending any flaming.
My comment about lslow96's opinion was based on ,,,, this is an Impala Forum and "most" ratio vs rpm vs highway vs town vs bla bla, discussions here is based on 255-50-17 thinking, or even shorter 275-40-17 tires run by many here .

The best mileage my car got was with 3.73 stock cam, aggressive tuning and convertor lock up. Better than the original 2.93 as most of the time on the highway it stayed locked in 4th

Your above chart, multiply by .69 to get a more meaning full "high gear"

Camshaft, there is no free lunch. you give somewhere to gain somewhere.

Hopefully you can find a happy medium picking up mid range without losing noticeable low end.
The ONLY mild LT1 cam I have ever put in was the Comp 304 . It is an old profile, there are likely better choices for small cams.
Even it at 210-220-114 still had a HP peak of 5900 in my car and as I said gave away some low low end power.
Crap load of timing and a small efficient convertor did cover that up.
Take my info as what it is , an opinion based on one cam swap in one car.
That said, it might be one more than some others cam swap advice you will get .
 

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Small, moderate stall , torque convertors in heavy cars .
45 years ago, there was a guy running around here with an 8" "Vitar" if memory serves.
We thought he was insane
The rest of use where running 11-12 high stalls locally done.
Difference was his worked , didn't slip appreciably at low- moderate throttle.
Our were junk . The Biscayne I was associated with, you just looked at the throttle and it was on 3000 !
The old way, local shops just clearanced the hell out of them, bent blades indiscriminately.
Might as well beat the thing with a hammer to make it slip more.

My home grown analogy, take a 4 cylinder mini van with its little torque convertor , load it up with crap so it weighs 5000 pounds.
It takes just as much power to drive it up a hill as it does a 5000 pound wagon.
It does that without undue convertor slippage or heat.
There is a lot more to it than the above and I do not profess to know all the nuances of convertors

A quality 9.5 lockup convertor in a lower stall ( repeat my personal experience was a 2600 Vigilante) will act as it not even there at light throttle, but when you put the coal to it will allow the engine to rev enough that it will be more into its power band.
Add in, the lock up , and on the highway there is basically no downside.
The common players are
Precision Vigilante
Yank
Edge

People swear by the Yank, I have not personally driven one.
I loved the Vigilante, think the quality is outstanding. Billet front end, full dia clutch
Edge, I had a 3000, it did everything they promised, but for street, Vigilante is my personal choice.

Coolers, I ran ONLY the stock HD system ( rad cooler through front air to oil cooler ) NEVER saw a temp problem in street and drag strip duty.
Not sure if it ever saw 200 .
Road coarse might be a completely different deal.

Get you lock ups programed well, I question if more cooling is required.

All opinion, but based on first hand.
 

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Hey man, sounds like you have some great ideas for your wagon. Always fun and educational modding our LT1's!

To add to what has been shared and suggested, I would do one of the following two options:

1. Keep your LT1 stock. Replace the front and rear main seals. Tune it up. Leave it alone. A stock LT1 is good for 250-300,000 miles of service if properly maintained. Since you are having the trans built, definitely upgrade your TC. Talk directly to Yank or other trusted TC manufacturer like Vigilante. They will recommend the proper TC to work with your setup. I really liked my Yank SS 3000 stall TC with my stock LT1. Don't cheap out on your TC. I love my 410 gears. It makes our fat pigs move quick. I drive in 3rd around town and OD on the HWY. BUT as stated above, no ABS reluctor rings available and mpg will take a hit. Check with Dan at CIA. I believe he may have a source for a 3.73 ABS reluctor ring. Don't forget to replace the stock POSI while you're doing the gears. Go with a quality HD one. You may or may not need a new driveshaft after the gear change. Check out Denny's Driveshafts. With the TriYs, TC, gears and a serious dyno tune will make your wagon a blast to drive and keep a lot of it's street manners. With this option, you can plan and prepare for a bigger build with your LT1 like a 383 stroker. Something to consider for a later time after you get your money's worth out of the stock LT1.

2. If you go with a cam swap it will be a domino effect. With over 100k miles on it, you should replace the CAM bearings. Along with them, you will need to replace your stock valve springs and pressed in rocker studs with screw in studs. Stock rocker studs pull out with the stock cam. The risk will be much higher with a high lift aftermarket cam. Should change the the timing chain while your swapping the cam. Same goes with the 1.6 roller rockers. Stock valve springs are weak! Need to replace them. Don't forget valve seals! Then if you are going to mod the stock heads, then the cost difference for aluminum ones starts to look appealing. Simply swap them out. But wait, GM LT1 stock heads or ones that have been worked over are 25 plus years old and getting hard to find. Aluminum isn't as durable as iron. May have to go with TrickFlow heads. So, as you can see, with just a cam swap you will have to do more mods. No problem with this if you are cool with the additional work and money. You sound like a person who wants to do it right and not take chances. So, as soon as you crack those valve and timing covers, be prepared and enjoy the go fast adventure. If you want to do the cam with all the necessary accompanying mods, I suggest you speak to Llyod Elliott. He has two cams that go with stock heads that may give you what you want. I really enjoyed the Crane 227 cam I had in my SS:
  • 212/222 .563/.562 114 LSA. 鈥 Idle-5800 RPM
    鈥淪leeper cam鈥 with smooth idle improving HP and TQ everywhere.
  • 218/224 .570/.565 111 LSA. 鈥 1500-6000 RPM
    Great low and mid range power with very mild idle and will easily pass emissions. Works with
    stock gear and factory converter. Comparable to popular Crane 227 cam and GM 845 cam.
Whatever you decide, remember to enjoy the ride man. This is suppose to be fun. Go fast. Don't die!
 
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OP

Agree with Lance...now my $.02

Back before I jumped into the deep end of the mod pool I felt, and still do, that the best street/hwy set-up on my SS was this

stock motor but 1:6 RR (crane gold narrow body aluminum), crane valve springs for iron heads (your stock ones are beyond done)

Ed Wright tune with 160 T stat (yeah more power)

Transgo shift kit on #2 (read not fing hard stun shifts but way better than stock)

2200 stall Hughes standard size converter (did the 2600 Vig and absolutely hated it on the street and trans temps were stupid high)

3:42 gears

stock 27" tires

This was one sweet ride IMHO...but again just my $.02

next step was ported LT1 aluminum heads and a baby 212/218 custom cam and I netted 100 RWHP.....and then the mod train hit full speed so consider how deep into the pool you want to get as once you do more than 1:6 RR on a 100k+ mi motor it has a HUGE domino effect as Lance notes
 

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I have a 6 speed and 28" tire so my 4.56 are not bad at all very comfy on the interstate but when I had an auto and 26" tire I ran 4.10 it was a world of difference over the 3.42
 

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Discussion Starter #14
Hi All sorry for the delay in my reply, I had the joy of FINALLY taking a family vacation to Hawaii that we planned last March - cancelled, rebooked for October - cancelled and was able to make it work this year. Typically for work and pleasure I am on 8-12 flights a year, this past year was the first time in at least 10 years that I didn't have travel booked...it gave me time to learn about and work on my vehicles though. If you look around, there is good to come from COVID.

Thanks @Lance , @BALLSS and @Mwilson1995 for your replies.
All of the input is helpful. I think I am going to go ahead with 3.42 gears with a TrueTrac posi, and may step down to a 27.6 tire from a 28.6, had been debating between both sizes. I most likely will replace the axels and bearings "while I am in there". Regarding the engine, I can see that a cam swap will lead me down a road I am not ready to follow. It sounds like there are some positive results from running 1.6 roller rockers with new valve springs, so I will look into this. It looks like a job I can handle if I take my time...good learning experience.

Again, thanks everyone for your input, I look forward to sharing my progress as things move forward. All of my QA1 suspension components have arrived. Most likely will not install the front stuff until the engine is pulled so that I can clean up the engine bay and do some painting without having to worry about overspray on the new parts. I think my next step will be something on the rear, coil over install or rebuilding the axel. I won't have time to get the engine/trans pulled for a few weeks, but can easily make some progress on the rear end alone with a few hours in the evenings here and there.
 
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