krazykane

Has anyone ever ls swapped a 84-88 manual and kept the doug nash? while id love a 6 speed I dont see the point in spending an extra 2 grand on a trans if i dont really need to. i got my od working how i want it, really no qualms with the trans. not 100% sure how much it can take.

VikingTrad3r

i know there is one guy who did it.

im a huge fan of the 4+3 and encourage u to search here and find the thread. its within the past couple years.

krazykane

really just curious what do you like about it in particular? do you prefer it over the zf1 in the later models or other vehicles 5 or 6 speed transmissions? im still new to cars. i learned to drive stick on this thing and i havent driven any other performance vehicles or stick shifts in general. i like the doug nash well enough since i jumped the ecm wires and made it fully manual.

ill search harder for that thread. all i did was search "doug nash lsx" on the forums search tool.

84 4+3

If it's a stock LS1 it'll be fine for a while... just no WOT shifts into overdrive and you'll be fine. The 4 speed side can take a half decent beating. The OD not so much.

stew86MCSS396

Claims he never completed the project but seems like he was a wiring harness away from completion.
https://www.corvetteforum.com/forums...-4-3-swap.html

Phobos84

To be honest unless you already have the LS1 I would save a pile of money and swap in an aluminum 5.3L. Same basic swap but the aluminum 5.3's are gen IV motors with better rods and heads. A simple cam swap will put the 5.3L way over the power limit of the 4+3 anyway. The best part is you can pick up a 5.3 in iron or aluminum for around $300. LS1 prices are crazy and just not worth it. Or you could do the iron block 6.0L for around the same price as the 5.3L.

From my understanding the only tricky part of LS swapping with the 4+3 would be finding a clutch that will work. Other than that it should be a fairly straightforward swap. LS swapping C4's isn't hard. It's even easier if you use Holley EFI.

cv67

Id call summit, clutch companies, someone offers an adapter of some type they are out there.
A worn out 5.3 out here starts at 1300, total rip. A rebuilt isnt much more (ca)
These kids think they are the only way to make any power.

84 4+3

You can find them cheap here but it seems like everyone thinks they have a hunk of gold with it lately. Been looking for a junk 6.0 to rebuilt for the work truck that finally crapped out... 300k miles out of it before it was done ain't too bad. Has basically zero compression left but still runs. But yea a core 6.0 was like 1400 at the local wreckers. Not even worth my time right now. Granted they are complete but still way more than its worth.

As for the clutch, surprised it is that tricky. The one I used was a regular McLeod 10.5 inch street for like every GM 26 spline in existence. There were also 11s that fit as well.

Phobos84

It might be worth the drive for you to go here.

Standard price on any engine with a warranty is under $350. They are having a pull a thon on the 30th so you could get one for way less. They always have 6.0L's in the yard. Most are LQ4's and the occasional LQ9. They probably have at least five 5.3's with around 100K miles. If you want some help I'll be there for the pull a thon on the 30th.

84 4+3

I'm working overnights that whole week and weekend so no time sadly. I think we've discussed this once before however.. that place is legit.

Phobos84

See I have an alternator motive for trying to get you or anyone for that matter to go there with me. For the Pull a thon you pay $50 for anything you can carry 20 feet per person. So if I pay $100 two people can carry whatever it is 20 feet. I can pick up half a V8 .

84 4+3

been a hot minute but I could still probably lug an assembled V8. Maybe not an iron headed Lq4 but an aluminum one for sure. Sorry I'm working lol.

gman35

you are the first person that I have seen saying the LS swap on the C4 is easy. I am planning on doing it too mine< can you tell me more. I thought the wiring would be a nightmare> thanks, Gary

Phobos84

I didn't think doing an LS swap on my 84 was that bad. That being said I ditched the gauge cluster for aftermarket gauges and went with Holley EFI. I originally used a stand alone factory modified harness with a 411 PCM. I feel that, that was a mistake. The Holley Terminator X gives you a new plug and play harness. I got the X Max which also gives you transmission control. I originally had a 4L60e but upgraded to a 4L80e that I built when I had covid.

If I had to do another one I certainly could have done it for less money. But the end result would have been the same. I would do Intellitronix or VDO gauges and either a Terinator X or a Domintor ECU.

I think the biggest thing that made it feel easy was this forum. There are a lot of great build threads were people show everything they did. Do your research first and stick to a plan.

If you would like to see my gauge setup or read about the new motor that will be going in my car over the winter check out my build thread here.

coupeguy2001

Anybody know what 6.2 liters is in cubic inches?
383.
so why not just run over to Summit Racing and buy a smallblock 383 that puts out 440 hp and 400 torque and save yourself the LS swap hassel?
and all your stuff will fit.
you can use a LT1 intake with a distributor hole at the back with custom tune.
if you figure you’re going to have your car out of action for months, and put in $5000 worth of labor, it might just be a bargain

84 4+3

it's actually 377 cubic inches. And reasons for: better heads, bottom end, and stock like drivability. A 450 hp 6.2 will drive like a stock l98 and make almost double the power.. and to put the same sized cam engine for engine you'll always be near a 200hp advantage. If you want nothing more than to go fast and don't give a crap about anything working, it's the way to go because it's just a building block and parts are relatively cheap for now. And you're shaving 100lbs off the front end too.

Phobos84

To me, for a street car if the cost of the motor (whatever it is) is $5000 then I'm not doing it. But the reason I went LS is cost. If all you want is 450 crank hp then a stock LQ9 with a $250 cam and $100 valve springs will do that. Total build cost for a low mileage complete motor and the cam and springs will all be well under $1000. I can't build power that cheap with any small block. But this is assuming that you are installing and building a motor yourself. I would never pay someone to do that for me. But not everyone has the space for it.

Other advantages are each plug has it's own coil, parts or more prolific, weight (assuming aluminum block), better fuel mileage, and usually a higher rpm limit than most small blocks, easier tuning because of the much better fuel injection and ignition system, easy flex fuel compatibility for even more power.

The only drawbacks to an LS swap really are buying motor mount plates and buying new gauges. That last one wasn't much of a downside for me. I couldn't get the factory cluster out fast enough. I couldn't stand it. But that's preference.

Armybyrd21

I did that years ago. Replaced that clunky pos with a t56 and I’m on my 3rd ls engine for this car

VikingTrad3r

Sorry i never replied OP. Not that my opinion matters but I'll answer seeing as you asked. I like it because its period correct for the car. its quirky. its easy, can't get lost in a 4 spd. and frankly, i like the 4+3 for the same reason i have always loved the c4's. They are an underdog. People trash talk them all the time. They raced in the corvette challenge, and, prior to that, c4's were ejected from scca because they destroyed everything else on the grid. all with a 4+3. I will absolutely put a 4+3 behind most likely an LQ9 swap (wife has a 2005 escalade esv in mint shape as family mover, when it eventually goes to car heaven, i will be plucking the engine first!).

I appreciate it is for what it is. Its mechanical, its got levers and pivots and making it a short throw requires nothing other than a hardened bit on a drill press to put the holes in a different spot on the shifter shaft linkages.

i learned to drive on the track with an 86 4+3 and was THRILLED with this transmission. I never, ever, ever, had to worry about missing a shift. I didn't use the OD on the track, no straights long enough. I did the shifter shaft businings, I think it was simply white nylon? So simple. I cannot say how much I love this transmission. I just love it.

I have also owned 2 automatic early cars. 4+3 a million times better. I also currently own a 1990 ZF6 L98 car, and a 1991 ZR-1 which obviously has the ZF6.

I can honestly say that I don't particularily enjoy one more than the other. I really don't. I LOVE a nicely operating ZF6 they are buttery smooth. But....I ALSO LOVE the clunky mechanical feel of driving the 4 speed. And I enjoy using the clutch to shift the OD! So easy!

I would not hesitate for one split second to buy another early car with the 4+3. In fact I am always looking for one. So far the only roach cars I have found have had the automatics and im just not intersted in those cars anymore now that I am a track junkie.

Hope you do what you want to do, and that it is a success for you my friend. Cheers.

OH....and btw.....I also own a 99 c5 with the t56, I would rather have a 4+3 than that POS t56. t56 was a massive downgrade from the zf6.

Armybyrd21

I’m the guy who did it a few years ago. I’ve since swapped to a
t56 though. I hate the clunky pos 4+3