Knurled. said:In reply to MotorsportsGordon :
If swapping a 4L60E in for the 4L60 is a pain, trying to fit 200-4R where a 4L60 used to live would probably be a nonstarter as well...
The solution to that could be th400 with something like a gear vendors overdrive if u want overdrive still. Heck if u modify the transmission tunnel u could go with a 4l80e.
In reply to MotorsportsGordon :
You're missing the point... a 4L60E would literally bolt in and work without fabrication, because it's the same trans, just electronically controlled instead of governor and TV cable controlled. And that still would apperently be a nogo.
I'm not necessarily disagreeing with the mindset. Dropping an engine into an engine bay is easy, making everything work is the "fun" part. And I have been burned many times by the thought of "Oh, it will all just bolt up, no problems."
For this post it might be better just keeping the 700r4/4l60 and having it built up. They can handle good power levels built up. Plus u can always have different adaptor plates used if thinking going a different motor route.
Sonnax is your friend with 700r4 builds
Why ever change a 700 or 4l60 at all? Other than rebuilding it i mean. I feel like you need to be making 500+ lb ft before you can lodge a serious complaint about it not being good enough.
It sounds like I would be happy with the results if just did some work with the current engine and calling it "tired" was probably an exaggeration. For now I think somewhere between 250-300 reliable, torquey, and unstressed horsepowers would be enough for my purposes. Sounds like that's realistic? There is an advantage to using what I have, and I guess there is something to be said for retaining the original engine for nostalgia's sake.
That being said: I have to ask myself, would the $$ and time I would spend hopping up the old tbi 350 really be any less than the $$ and time I would spend swapping the drivetrain for something else? (5.3 vortec, LT1, etc) After all, I do like the idea of potential to make bigger power down the road. Whatever I decide will happen over the winter, or maybe even the winter after that so I would have plenty of time to find a good deal on an engine/trans and acquire all the odds and ends for a swap.
I also have to decide how big a project I want this to be but that's not really a decision anyone can help with 
I do like the thought of turbo V6 for the sake of being different, but I think a lazy V8 suits this car better.
I have to ask myself, would the $$ and time I would spend hopping up the old tbi 350 really be any less than the $$ and time I would spend swapping the drivetrain for something else? (5.3 vortec, LT1, etc) After all, I do like the idea of potential to make bigger power down the road.
Well, the stock bottom end won't be a limiting factor until probably 450+hp if you're talking durability. Putting bolt on (or nearly bolt on) parts on the stock engine lets you not mess with the stuff you don't want to mess with, like a working accessory drive and all the hoses and wires and brackets that go along with it. Not that that stuff is hard, but if you're only looking for 250-300hp and the stock setup with minor mods will support it, why go all-out on a new platform?
Take a look at this: Vortec heads on a tbi
I basically suggest this ^. Stock vortec heads, a nice carb mani with a TBI adapter plate, and preferably a cam and full exhaust. Unless you want to make 400+hp n/a later, you probably won't outgrow the vortec heads, and you definitely won't outgrow the exhaust system and 'need' it anyway no matter which route you go. The link above claims ~40whp over a stock tbi setup with stock exhaust and a stockish cam and if you believe powertrain loss numbers, 260chp which is right there with a stock Impala SS.
If you want to add more power later you would basically only need to change the cam and part of the intake tract. A quick google search suggests you can make 450hp on unported Vortec heads through a typical Edelbrock RPM dual plane carb intake. The stock GM tbi throttle body won't allow that, so at that point you could decice to go carb or aftermarket TBI on the manifold you'd already have, convert that mani to multiport or something like an LT1 intake on your choice of engine management.
LT1/L99 didn't make it into B-bodies until 1994... at least from the factory.
Yours would have come with a TBI.
There is power to be had in the 350, but you're looking at a complete re-do. TBI 350s were all well-matched for the 190hp they made, so its not like you can just swap cams, heads, or put headers on it and release the magic genie from the lamp. TBIs had dished pistons, the worst-flowing production heads Chevy ever put on a V8 (and that even includes all the way back to the old-school 50s heads), tiny cams (180s intake duration and 116 LSA), low compression.... its a whole package of well-matched smog-legal goodness. You will also find that from 87-93, Chevy did some fun mix-n-match as they transitioned over to the newer generation of small blocks (94-97 Vortec). In most of the trucks you'll find a block with roller cam provisions (taller lifter bores and bosses for the spider retainer) but nearly all of them got flat cams. In cars, there were more roller cams, but its not a guarantee. If you pull the intake and don't see a roller-ready block, sell it. Seriously. There is no reason in 2018 to build a flat-cam engine, and roller conversions are expensive. (special lifters, dog bones, etc. Think $1000 for a conversion cam kit instead of $150 for just a cam).
So, if you pull the intake and see a roller block, it's worthy of using, however you'll need a clean-slate rotating block. You can basically keep the block, crank, and rods, but everything else will need to be something else if you want to make power. My go-to recipe for a 300-325 hp small block is aftermarket Summit iron Vortec heads, vortec carb intake (ZZ4 intake is expensive, but look to marine carbed intakes from a boat boneyard... same intake casting with bronze-lined coolant crossover and often $20). flat-top pistons with valve reliefs, and a Melling cam. I'm trying to think of the cam number. I think its 22124, but I might be remembering the flat cam part number. Its something like 194/208 duration on a 112 LSA IIRC. It can use stock valve springs from a roller application, but they might start to float at about 5200. If you don't get the aftermarket Vortecs, make sure to get a retainer kit that allows for .550" lift. Stock Vortecs are only good to about .470". That will get you a 9.5:1 assembly that will easily take 87 octane and make around 300 hp.
If you live in smog territory, you can easily keep it TBI, but take your TBI and smash it with a large granite rock. Or sell it to someone who still thinks they are worth something. (can you tell I hate the small block TBI?). Instead, replace it with a BBC TBI. They are actually decent-ish. Well, they still suck in my opinion, but they at least flow a decent amount. An unsuspecting inspector (say that ten times fast) will never notice a thing. If you live in a place that does a sniffer test, you should be able to tune it to pass a tailpipe test with a good chip burner.
If you don't want to put all of that money and effort into a SBC, there is a lot of aftermarket support for LS swaps. Even if you do have to smog, you can likely get by with it with a little redtape.
If you don't have to smog it, the world is your oyster. Caddy 500 weighs about the same as a 350 and makes mountains of torque. Mine was 390hp/5xxtq (dyno couldn't hold the torque, so it was probably north of 550 lbft) and got 18 mpg in a 66 Bonneville. I set redline at 4700 and used 2.93 gears and a TH400. Cruised all day at 1900 rpms and roasted tires.
Duramax would be killer. Probably get 30 mpgs in that wagon.
Oh, forgot one thing.
LT1 is a great engine. The iron-head LT1 used an intake port design that was so good they actually copied it exactly for the Vortec head in 97. It was a 21% flow improvement over L98 TPI heads, a 16% improvement over the aluminum LT1 head, and a 6500000% improvement over the TBI head (the last number is fake)
Don't listen to the people saying the Opti-spark is bad. It is amazing. Where it got bad was two ways: the first design didn't incorporate a breather tube and condensation corroded the caps. Secondly, the weep hole on the LT1 water pump drips directly on the opti. A short piece of 1/8" brake line and some epoxy cures that. The opti gets a bad rap because people expected too much of them. The optical pickup is bulletproof and one of the most accurate you will find anywhere. The cap and rotor are just that... a cap and rotor, and need to be replaced every 80-100k.
Having said that, if you're spending money on an engine swap, and LT1 is evolutionary, not revolutionary. Functionally speaking, it is a 1-piece rear SBC with different heads and coolant passages. The reverse-flow cooling system is very nice because it allows for the cooler water to hit the heads first. This allows a little more compression on cheap gas, but its nothing to write home about. An LS is cheap, plentiful, and makes more go for your dollar these days.
By 93 the cop Tbi 350 was making 205 hp and in 94 the truck version was 210 so u can build power out of the tbi it’s a good old sbc Chevy at its heart afterall. Changing heads etc will definitely help make more power.
there are duramax swaps out there like that you will need to do a body lift to fix the Allison transmission in and probably have to beef up the chassis etc to handle that combo.
Vigo said:Why ever change a 700 or 4l60 at all? Other than rebuilding it i mean. I feel like you need to be making 500+ lb ft before you can lodge a serious complaint about it not being good enough.
Connecting a TV cable to a drive by wire engine is... problematic. Even the cable throttle GenIII does not make it easy to run a TV cable due to routing issues.
Isn't this where we came in?
After driving the Custom Cruiser to work all week I've come up with another option: leave it stock, enjoy the wagon for the big lazy cruiser that it is, and buy a late 90s Camaro if I want to go fast with a Chevy V8.
Hmm...
TV made EZ makes a solution to for the TV cable to work with an LS1 for $190, of course this is only for cable driven throttle bodies, not sure about DBW solutions. I think the only other thing you'd need to make the trans work is maybe a flexplate spacer and a way to control converter lock-up.
Vigo said:The old vortec crate motor which was stock vortec heads and stock vortec truck cam made 290chp with a carb manifold. So yeah, vortec heads and any kind of cam with a carb intake and headers is 350hp. The question becomes whether that's actually cheaper or more desirable than the alternatives.
Agree and disagree in his case. His TBI has dished pistons. Just swapping on Vortec heads will mean about 8.5:1 compression. Regardless of what ever else you do (within a range of matching cam durations and other things) he will be rather dramatically restricted. 250-275 would be easy, but to get 350 hp he really needs to get rid of the dished pistons. There are no aftermarket or factory heads that will bring the compression up enough, and even if there were, dishes with tiny chambers = very little octane tolerance and very poor swirl/efficiency. The LS1 I'm building for instance is 11.3:1 and I expect not a single ping with 91 octane and 550 hp. But dished pistons with tiny chambers, 9.5:1 might detonate with 94 octane and only make 300 hp. It would just be mismatched parts choices and I don't think he'd be happy with the performance, trade offs, or fuel suckage.
BlueInGreen - Jon said:After driving the Custom Cruiser to work all week I've come up with another option: leave it stock, enjoy the wagon for the big lazy cruiser that it is, and buy a late 90s Camaro if I want to go fast with a Chevy V8.
Hmm...
Tbi 350s make lots of torque and run stronger then the horsepower numbers say because of that. I know the tbi 350 in my dads 94 gmc ext cab felt strong.
Making decent numbers with a 350 TBI motor has been documented eight ways to Sunday. A mild refresh of the shortblock and stock heads, a bit more cam, work on the intake side and everything you can legally do aft of the exhaust ports is what I'd still recommend. These things are also slow, soft shifting cars, and the trans is probably a bit tired at this point anyway. A refresh of the stock trans with some kind of shift improvement (I hate to say "shift kit" as that to me says tire-chirps every shift) might be nice.
2.0L turbo. 280hp, over 300lb/ft torque. Better numbers than the Vortec in my ‘96 Silverado Ext Cab.
pres589 said:Making decent numbers with a 350 TBI motor has been documented eight ways to Sunday. A mild refresh of the shortblock and stock heads, a bit more cam, work on the intake side and everything you can legally do aft of the exhaust ports is what I'd still recommend. These things are also slow, soft shifting cars, and the trans is probably a bit tired at this point anyway. A refresh of the stock trans with some kind of shift improvement (I hate to say "shift kit" as that to me says tire-chirps every shift) might be nice.
I agree completely that you can make good numbers with a TBI motor, its just that they start with every possible crippling thing going for them. They're great and well-matched for the 200hp they make, but the comprehensive overhaul they need often means spending much more to get the results you need compared to starting with a good used vortec longblock for $250. Starting with flat tops and great heads for $250 is cheaper and easier than buying $500 vortec heads, $200 pistons, $40 rings, honing cylinders, yadda yadda, and putting it on a TBI block that may or may not be set up for a roller cam.
A TBI engine is just like any other SBC... it can make power, its just one of the weakest starting points for a build from a parts standpoint.
Also agree that any of the GM transmissions will be a fine choice at the modest power levels we're talking. If the 4L60 in there isn't slipping, I would leave it alone unless you're going over 350hp. A mild shift kit can't hurt, but make sure you get a quality separator plate for the valve body. The check ball for the 1-2 shift circuit likes to whack into the plate and eventually peens the hole to the point where the check ball either gets lodged in the plate or blows through it... and that is at stock pressures. A shift kit will accelerate that problem. It isn't a major problem when it happens. You either get no second gear (lodged ball) or a super hard 1-2 shift (blown through).
There are even a few direct swaps between transmissions with a couple tweaks here and there but I see no reason not to use the 4L60/700r4. The only reason I would switch to a 4L60E is if you are switching to something like an LS where the bellhousing is a bit different and the TC bolt pattern is different. Instead of "adapting" an LS to a 700r4 and then finding ways to do a control cable, it might just be wiser to get an LS/4L60E together and let the computer do its thing.
The other fun option is that a T56 is a direct bolt-in replacement for a 4L60/700R4/4L60E. Same length, same crossmember, same spline count, the works. Take one out, put the other in. You would just have to program the computer (or burn a chip depending on which one you're doing) to have the flash for a manual trans vehicle. Conversely, you can do a non-electronic auto trans behind an LS by just telling the ECU that it's a manual trans program and it will ignore the transmission altogether.
There are also plenty of cable throttle operated LS motors out there. The ECUs are a little different between electronic and cable throttles, but you can easily do a cable-operated throttle on an LS which would let you do a control cable with a little fabrication. You can do a cable throttle on an electric throttle ECU, but you have to check the ECU before you go the other way around. There is one driver on the board that is sometimes missing in cable-op throttle vehicles. I will likely be converting my LS from electronic to cable throttle... mostly because I don't like the tiny lag with electronic throttles. I'm sure I'd get used to it, but mine will have a T56 manual and I just prefer my foot to be physically linked to the throttle blade.
I also think that a few companies make a trans control cable kit for just this purpose. They make a cable and bracket that attaches to the actual accelerator pedal so that you can do an old-school trans in an electronic throttle vehicle. At SEMA one year, someone was also showing a prototype of a system that piggybacked off the factory electronic throttle. It was basically a second throttle control motor with a bellcrank on it. When you pressed your foot down and the computer opened the throttle, it also operated this second motor to pull on the cable. Not sure if it ever made it to production. The display prototype they had at SEMA wasn't working, so maybe not. Check TCI's website. I think it was their booth. Nice idea. It just mounted by taking two pan bolts out to mount the assembly.
Compression numbers are going to make a single-digit percentage difference in peak hp. With goals this mild I think they're pretty close to the bottom of the list of places to go looking for power. My .02.
As far as the throttle cable thing, i agree that's valid but i guess i should have been more specific. If i was swapping to an LS i might also swap to a 4l60e, but i don't think it makes sense to swap to a heavier trans with more torque capacity and more parasitic loss for an engine that doesn't have a hope of breaking a stock trans in good condition anyway. Also, my .02.
It's odd to me to think that a TBI engine from 92 will need pistons and a Vortec engine from circa 96 won't.
Vigo said:Compression numbers are going to make a single-digit percentage difference in peak hp. With goals this mild I think they're pretty close to the bottom of the list of places to go looking for power. My .02.
As far as the throttle cable thing, i agree that's valid but i guess i should have been more specific. If i was swapping to an LS i might also swap to a 4l60e, but i don't think it makes sense to swap to a heavier trans with more torque capacity and more parasitic loss for an engine that doesn't have a hope of breaking a stock trans in good condition anyway. Also, my .02.
Compression alone, yes. But proper compression is the baseline for cam selection and a well-tuned combo. With 8.5:1 and TBI swirl port heads, that engine is going to really top out at 250-275. If you start with 9.5:1, you have the physics to support 400 or more. I would never raise compression as a means to get power, but you need the compression to support mods that make power.
I built a 454 once and did some wrong maths. I was shooting for 9.6:1 but ended up with 8.7:1. The cam I chose was in the 234/244 duration range. I was expecting 450hp but only got about 390 of the wussiest most awful horsepower I ever knew. I couldn't tune the timing right, the idle vacuum was pathetic, and it ran like crap. Once I found my error and swapped heads, I was making 455 hp. In that situation, a one-point jump in compression added 65 hp because it put me back into the right physics range.
And I agree... he won't be breaking the stock trans
pres589 said:It's odd to me to think that a TBI engine from 92 will need pistons and a Vortec engine from circa 96 won't.
Stock TBI piston looks much like this with a little deeper dish. (this is a 67-83 generic dished piston). It adds about 10cc volume and kills swirl/quench. It also has a higher pin, meaning it ends up about .025" in the hole (below deck) which adds even more and kills more quench
Vortec piston looks like this. Some came with only 2 valve reliefs. They have lower pins and sit .010" in the hole. The piston also works very well with the updated chamber design of the vortec heads making them great with quench and detonation tolerance is greatly improved. You can get away with 0.5 to 1.0 more compression on the same octane for most combinations compared to the TBI.
For shear insanity sake .... I say a 6.6 Duramax LB7 with a ZF six speed......yes that's diesel powaa!!! 300hp/550lbft @ 1800rpm...out
759NRNG said:For shear insanity sake .... I say a 6.6 Duramax LB7 with a ZF six speed......yes that's diesel powaa!!! 300hp/550lbft @ 1800rpm...out
berkeleying preach it. Not to mention, the 30 mpgs he'll get wouldn't be awful either.
Dad has an LB7 with 30-over injectors, cold intake, exhaust, air dog pump, and 5 position chip. Dyno'd at 938 lb ft to the rear wheels. On the way home from the shop I cranked it up to position 5, hit tow-haul mode, and floored it on the highway. Getting sideways and leaving a cloud of tire smoke at 70 mph was something I didn't know was on my bucket list until that moment. Cross that one off.
Back in the carbureted days you needed a lot of compression to support big cams because the cams wrecked the low rpm VE so much that your 'vacuum signal' was garbage and you couldn't easily tune a carb to work properly with that. Higher compression would improve the vacuum even with a big cam and let the car at least idle at 1000rpm and you'll just have to change your fouling plugs if you actually let it idle very much. With fuel injection you can tune an engine with a big cam and low compression to still run properly, or at least as well as that cam can run. Fuel injected cars can have big lope and idle at 600rpm and not ruin spark plugs . So high compression is not nearly as necessary when upgrading cams as it used to be in the carb days. Your static compression and your VE will interplay to dictate your 'dynamic compression' and if you play your cards right you can use high compression that would definitely detonate at low rpms with a stock cam, then use a cam that knocks down your VE at low rpms to the point that you don't detonate under part throttle, and then end up with a great ve/dynamic compression at higher rpm where you'll only be when you're flooring it (and running rich) and make a bunch of power and not blow up. But all of that is irrelevant to trying to make 260chp on an 8.5cr 350ci, which doesn't require any trickery at all. Just slap vortec heads and a vortec-equivalent (which is STOCK, just not for a 94 tbi) or slightly hotter cam in it and you're there. I'm not trying to get testy with anyone, i'm just really trying to avoid the impression that you need to tear into the shortblock to make 300hp. Make that first hurdle too big and guess what ends up happening, the car doesn't get modified at all. OP already dropped hints that talking about major work for minor returns (cr) will lead to exactly that. My .02
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