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Carb, 383 Swapped 92 Caprice

11K views 38 replies 15 participants last post by  coryblackcb 
#1 ·
So my block got blowed up from sitting through 5 winters with watered down antifreeze. Since the TBI sucks ass anyway, I'm going with a carb on this motor. The block has been cleared for the 400 crank but nothing has been built yet, I'm hoping to be testing in the engine stand by the weekend. The order from Summit was crazy huge but most of the parts have been free. The block was donated, pistons, rods and crank are from the last motor so all said and done I should be under 2 grand.

While I waited for the engine parts I got busy with other stuffs like replacing the SStreetlights with cheap Asian built crap that was cheaper than 20 year old OEM lights.



Painted the gauge bezel and got some new gauges to put on the A-pillar.





Pulled the wiring harness out and started weeding out the things I'm not going to use. I've got it down to; speed sensor, wipers, voltage regulator, head temp sensor, oil pressure sensor, fuel pump and A/C and the other transmission plug that I think is the gear selector switch?





Plugged up the old o2 sensor bung too, still working on ideas for plugging the MAP sensor hole.

 
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#3 ·
After pondering it for a while, decided to use water weld on the MAP hole.



I got the gauge senders through the firewall, I had to remove the parking brake pedal assembly and widen the slot that was conveniently located right where I needed a hole. Got the pillar pod on and everything is ready to be wired up.



The motor is finally gonna get built this weekend!
 
#6 ·
Today I'll be in the shop all day building the motor, picked up the new block from the machine shop on Friday and it ended up costing $1000! It used to be $10 a hole for boring and now it's $25 but I really can't complain with all the stuff I've been getting for free. I had them thread the lifter galley plugs.



The pistons were in great shape.



I'll be using one-peice pushrods this time, these were free. The only bolts that will be re-used are the head bolts but the rest are new and were donated.



The new cam is really promising, I like the thought of variable valve duration too.

 
#7 ·
I didn't quite get it finished yesterday but I did get everything up to the rockers on. Incredibly, a half inch of lift isn't too much for the original LO5 rockers. I had to modify the throttle linkage plate with a vice and drill press but it fits perfectly on the new manifold.

The crank scraper was free, I had to cut out the oil pan baffles for it to fit.



Got the manifold and covers all mocked up for fitment of the throttle linkage. There's no rear crossover so I'm going to have to run a new heater core hose up to the front.



This is basically how it will look though, the valve covers will be gloss black with the tops of the fins buffed. These are the real deal Mickey's not reproductions.
 
#9 ·
Had it on the engine stand Monday night and fired right up. I'm gonna use black plug wires in the car to match the distributor and the valve covers, they look so good black. I gotta re-paint the headers too, they have gotten nasty over the years.



I ordered Z06 rims and adapters today, not really excited to see how they look tucked in the skirt though. This is the style I'm talking about, I'm not a big fan of the newer ones

 
#17 ·
lookin goon.. question.. theres always been talk about the distributor using anything different that the caprice having a hard time getting under the cowl ?

the way i install my HEI distributor is to slide it thru the intake manifold then install both parts together. its a pita but the only way ive found to do it. you can swap your cap and rotor with out any problems but install and removal of the distributor requires pulling the intake manifold (at my house anyways)

the builds looking good, keep it up
 
#11 ·
Very nice build. I am excited to see it finished. Way to be different going with carb. :)

Why did you go against the TBI? Simplicity? You can get to 400hp+ and have computer tune-ability.. Just curious..

What are you plans with the car?


Keep it up!
 
#12 ·
My plan is to fix some of the body work, like dents in the driver's side doors and radius the skirts in the back. I don't want to make it an Impala clone but I do want to get the SS grille and spoiler. Maybe smoothie bumpers too depending if they're in the budget. Further down the line I would like to get a 77-90 box caprice coupe and do a body swap.

I decided to go with a carb for simplicity, you can still tune it (no laptop required) and the HEI can be tuned also. I'm a little wirried about it clearing the cowl though, it's only an inch taller than stock but much wider. A carb cleans up so much of the wiring too.
 
#16 ·
My plan is to fix some of the body work, like dents in the driver's side doors and radius the skirts in the back. I don't want to make it an Impala clone but I do want to get the SS grille and spoiler. Maybe smoothie bumpers too depending if they're in the budget. Further down the line I would like to get a 77-90 box caprice coupe and do a body swap.



I decided to go with a carb for simplicity, you can still tune it (no laptop required) and the HEI can be tuned also. I'm a little wirried about it clearing the cowl though, it's only an inch taller than stock but much wider. A carb cleans up so much of the wiring too.
I like the radius idea. I've never seen it done on a 91-92. I think its a great idea.

I understand what you are saying about the carb. I think its a nice unique build cant wait to see it complete. I would check to see about that HEI clearance. You may have to put the distributor in first then the cap. or go with a smaller setup with a seporate coil.
 
#15 · (Edited)
I'll explain the free stuff. One of my friends is a hoarder and he's trying to clear out some of his "collection" probably to fit more crap. He's got a ton of stuff that he never used and probably will never use in the future and a friend in need is a friend indeed :D

Motor is done with the stand and needs to be tore down for inspection. There were no leaks and no shavings in the oil, I just want to double check the valvetrain clearances.



I got a picture of the finishe throttle linkage plate, looks factory eh?

 
#18 · (Edited)
Thanks for the tip, the manifold is already sealed so I'm hoping I don't have to take it off. It's been slow going this week, I've been busy figuring out rims and suspension. I'm gonna run C5 Z06 rears in front and back with 245/45's, they are a little wide for the front so I'll have to update the bumpstops. I got 1.5" spacers for a total backspace of 6" and the wheels are really close to the frame in the rear. The spacers were measured to 12/1000" which is pretty good in my opinion.



You can see the body work that I need to do, both doors have a crease from front to back and a fat dent in the rear quarter. I'm going to go with Impala mirrors too, if anybody wants to sell me a spoiler and mirrors for cheap (like $100 shipped) let me know.



The front is crazy lifted from the lack of engine weight but I want to lower it more anyway, I'm thinking Hotchkis springs front and rear.

 
#19 ·
Finally an update, the HEI distributor is to blame. Dropped the motor in and there was absolutely no way it would fit under the wiper. After lots of pondering, came up with the idea of a removeable plate. It's much easier to remove a plate than the whole engine if I need to pull the distributor for whatever reason.



 
#22 ·
I discovered that the cap will not go on without the cover removed also, changing the screws to hex heads after fighting to fit a screwdriver back there. I thought about going to a mechanical fuel pump but the electric is almost brand new so I'm keeping it and using a new regulator.



The wiring kind of has me going ??? I have all the grounds finished up and the wipers are the only things that work. Fuel pump is my next obstacle, I can't use the factory oil pressure sensor because this block isn't drilled for it. It's not like I'm upset about losing my idiot light but I can't figure out why the oil pressure sensor would be in the same circuit as the fuel pump. I went through the diagrams and labeled all my loose ends, less than a dozen total, so now I just need to test how to turn on the relay to get fuel pumping.

The cylinder head sensor is in the manifold now and that goes to the gauge in the factory cluster as well as ties into the A/C. I just want the A/C to come on and off when I turn it on and off not temperature controlled like the ECU did during engine warmup so that concerns me a little. The top radiator hose won't work with the valve covers so I'm going to get a steel braided one also because the polished thermostat neck is larger diameter.

I rotated the back of the alternator case so the power isn't so close to the valve covers and I'm going to use the point where it mounted to a support in the rear for a battery ground. Anybody that knows the wiring really well pleas chime in with some advice, I'll just be shooting in the dark until I hit something.
 
#23 ·
I've got the wiring figured out, The light blue wire to positive is what turns on the A/C clutch and the oil pressure sensor gan be removed completely. The orange wire that splices is just a common constant power and the grey spliced is common ground. The red fuel pump prime wire sprays fuel when connected to positive. All I need to do now is cut the fuel lines down and get a new heater hose.

I've also been working on my stereo project. I'm going to have the battery sunk into the bottom board and a top board that goes across the top for boxed 6x9's. I'm just unsure how I want to finish it, with carpet? painted? wrap?

 
#24 ·
Most of the wiring is done in the engine bay, I pulled a switched power lead from the right side through the harness and I'm bundling it with the tach lead, oil pressure and ignition power along the firewall. After that's done all that's left is connecting the throttle linkages and plumbing the vac hoses. I had to use a PCV valve in the left bank because the heater core hoses are so close and I'm keeping the charcoal canister and power brakes so all that needs plumbing. I turned on the ignition and moved the a/c switch without connecting any of the leads and the clutch worked. I still have to wrap up all the loose wires on the inside of the firewall but should be done with all the wiring in one more day's work.

 
#25 ·
Finally got it running in the car today! I had to go with a serious fuel pressure regulator to tame the in-tank pump. Got the pressure down to 7 lbs but now my fuel level gauge is pegged way past full tank always. I'm gonna bleed the brakes again and give it the first road test in over 5 years tomorrow

 
#29 ·


First impressions are great, pulls strong and very responsive. The carb has the air bleeds opened up just until the motor dies for emissions but now that I'm exempt they will be going back down. Some problems I noticed; the speedometer worked for 4.8 miles and is now stuck at 29mph, fuel level gauge wasn't working but now it seems to read accurately.

The 700r4 is bone stock with a deep finned pan so it's now the weakest link. It has held up just fine with the old 383 but it had 4.10 gears in it back then too. I'm running 26" tires and 3.73 gears now so I might need to beef up the trans soon.

Ride height looks great with the Hotchkis springs, I wasn't expecting it to be so low. They settled quite a bit after driving only a few miles. I'm not used to scraping anymore so that's could be a problem. The lowest point will be my trans drain plug when the exhaust is welded up and I can get rid of all the clamps

Anyhow, I can do you one better and show you how she went.

 
#30 ·
I had to scrap the old throttle plate and buy new. It doesn't have provisions for cruise control so that's been removed too.



I'm having a few issues with the wiring still. My speedometer worked for 4.8 miles then quit. It goes down to 0 when the key is off but as soon as the key is on it goes to about 28mph and the odometer stopped turning after the 4.8 mi. I double checked the connection on the gear and it is solid, There's still a few cut wires where the computer used to be so I have some experimenting to do. I'm really happy with the power but I need to get rid of the flex fan and put in the old clutch type, it makes so much noise I can't hear the motor.

 
#31 ·
Any reason why you would not run a set of electric fans, they would conserve HP and MPG over a mechanical fan.

Every so often in your drive I hear a noise like something hitting or grinding, happened just when you pulled into the driveway.

Now with that out of the way, I love it, Im old school and love carbs and less sensors.
 
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