My 1990 383 Caprice Classic

Hi fellas, new to the forums but have been reading awhile and I just have to say that I think it's great that there are other B body enthusiast that have come to gether to share their projects and their knowledge!  I've gotten several great ideas for my Caprice Classic by reading the forums here thank you!

First off I've been driving this car since it was my dads in the mid 90's. My Caprice Classic rolled of the plant in August of 1990 in Arlington Texas and was owned by one little old lady in South Dakota before being sold to my grandfather in 1995. I remember seeing it for the first time and thinking how old, boxy and uncool it looked. Those of you here will appreciate how little I knew then. It came with the 305tbi which offered decent power and excellent highway mileage which came in handy as it has always been used as a road car and has been driven across country several times. The car survived the adventures of my adolesence and I ended up buying her in 2004.

The moment the car became mine it was as if I was Han Solo at a Sabbacc tournament and this was my Millennium Falcon and since then I've made many "special modifications" as well as having to fix or change many a part.  

As she sits now

383 Stroker 600cfm edlebrock Chevy HP dualplane intake, MSD, Hedman Heads, 3" Flow master exhaust (no cats)
Heavy duty radiator new heating and cooling system
Stage 2 built corvette 700r4 custom crossmember with oiler cooler and 2200 stall 2:56 gears
varible rate rear springs and 9c1 heavy duty suspension monroe sensa trac in front
frame reinforcment
Stage 2 tow package
Xenon 7500 HID bulbs

Hi, welcome to the forum!! What a great story about the car and it sounds like you have one awesome set up.

Hey welcome! when you can, post some pics of it!

Welcome!
Very nice ride!

Very nice ride indeed glad to welcome another B Body aficionado !

Apparently I am exceeding bandwidth I may have to use a 3rd party sight or make a few post...

Very nice, out with the old and in with the powerhouse! I bet that car comes alive! Maybe a 383 is what I should build for mine. Still thinking about a big block though too. At first I thought that was snow in that one pic until I looked closely.

Holy smokes!! I've never seen engine compartment mold and fungus get that bad!

Lol, jk!

Ha ha guys! Being a primarily Arizona car the car had loads of red sand but I've never had to worry about the rust
Yeah the larger powerplant (which became a 383) was a ten year dream for me, I love it! The driving experince has always been great in the Caprice (I feel like a million bucks driving this car) But now that I've extended my own blood and sweat and put something a little different and special under the hood/drivetrain/suspension its simply amazing. I intend on building up a pair of heads and going all roller rocker on it, but for now I'm just switching out the rockers and push rods to COMP cams as I hear they have a tighter ratio profile than stock stamp steele GM stuff. I am totally hooked, this car has been a school of mechanical engineering for me and although I wish I had spent a bit more money or built the car myself to have proper heads put on it I strongly recommend a 383. Buuut maybe that's just because I havn't gotten into a big block yet The 427 has always been an attractive motor.

Yeah, the stamped ones aren't nearly as accurate as the aftermarket ones especially if you have a healthy cam. Are you going with machined aluminum or stainless?

Just going eith the stamped steel ones, http://www.summitracing.com/parts/cca-1212-16
I've bent three push rods and have now broken two rockers and yesterday when I was looking at the valve springs they didn't seem to be set correctly, any advice on what springs I should be looking for? Thanks!

383Falcon wrote:Just going eith the stamped steel ones, http://www.summitracing.com/parts/cca-1212-16
I've bent three push rods and have now broken two rockers and yesterday when I was looking at the valve springs they didn't seem to be set correctly, any advice on what springs I should be looking for? Thanks!

These are better suited to your engine. http://www.summitracing.com/parts/cca-1412-8?seid=srese1&gclid=COjmqv6V5MACFYU9aQodzF8AHA

Something in your valvetrain geometry is off if you're breaking parts. I wouldn't drive the car until it's properly fixed.
It sounds like the springs are binding. What type of cam are you using? What's it's specs? What heads? Was there any machine work done to the heads? Are you sure you're using correct length push rods? Where in the RPM range is the damage occurring?

Sweet Seventy9 wrote:

383Falcon wrote:Just going eith the stamped steel ones, http://www.summitracing.com/parts/cca-1212-16
I've bent three push rods and have now broken two rockers and yesterday when I was looking at the valve springs they didn't seem to be set correctly, any advice on what springs I should be looking for? Thanks!

These are better suited to your engine.  http://www.summitracing.com/parts/cca-1412-8?seid=srese1&gclid=COjmqv6V5MACFYU9aQodzF8AHA

Something in your valvetrain geometry is off if you're breaking parts.   I wouldn't drive the car until it's properly fixed.
It sounds like the springs are binding.  What type of cam are you using? What's it's specs?   What heads?  Was there any machine work done to the heads?  Are you sure you're using correct length push rods?  Where in the RPM range is the damage occurring?

Will roller tiped rockers work with a flat tappet cam? I have an enginepro PN#MC1991 cam with 465/465 224/224 112lc 107lcl Speedpro aluminum flat top pistons and the heads are either 8998920 or 3998920 and 3888820 or 8888820 which I can't find anything on and they have no work done but are supposed to be rebuilt.. I don't know what spring bind looks like but the valve spring retainer didnt look right.. I'll take some photos. I've got a pushrod length checker on its way from summit, everytime I've had a problem it's been in the 2500 3000 rpm range..

383Falcon wrote:
Will roller tiped rockers work with a flat tappet cam? I have an enginepro PN#MC1991 cam with 465/465 224/224 112lc 107lcl Speedpro aluminum flat top pistons and the heads are either 8998920 or 3998920 and 3888820 or 8888820 which I can't find anything on and they have no work done but are supposed to be rebuilt.. I don't know what spring bind looks like but the valve spring retainer didnt look right.. I'll take some photos. I've got a pushrod length checker on its way from summit, everytime I've had a problem it's been in the 2500 3000 rpm range..

Sure, you can use roller tipped rockers with your cam.

The heads are probably #3888820, 1972-1975 cast iron off of a 350. 1.94/1.50 valves.  Early smog heads. Your engine is telling you it hates them, lol! J/K Seriously though, they're killing the potential of your 383.

Spring bind is when the spring compresses fully and the coils hit each other.  It's usually caused by too much lift on the cam vs compressed height of the spring.  Sometimes the spring it's self is weak and causes it to bind too.  A weak spring will seem fine at idle and usually isn't a problem until you get into the mid to upper RPMs where the speed and force of the rocker arm pushing down surpasses the springs ability to push back.  When it can't push back, it collapses and the coils hit.  

Let's see.... it happens in the mid RPM range and you've observed an issue with the retainer.  So far, it sounds like a weak spring is what evidence is pointing to.

Is the problem isolated to only one head?  Or cylinder?  Or only one valve?  Were the heads fully assembled when you bought them?
The MC1991 is a hydraulic cam so lash shouldn't be an issue.
The cups on the rockers don't look galled but I have to ask, are you sure the top end is getting proper oiling?

If your running stock springs, i know those have a max lift of about .460 before some funky things start happening. It sounds like your pushrods are too long, or you are getting some serious coil bind. You running hyd lifters or solid? Did you preload or set the valve lash correctly? Are you using 1.6 rockers or stock 1.5?

[quote="Sweet Seventy9"]

383Falcon wrote:

Let's see.... it happens in the mid RPM range and you've observed an issue with the retainer.  So far, it sounds like a weak spring is what evidence is pointing to.

Is the problem isolated to only one head?  Or cylinder?  Or only one valve?  Were the heads fully assembled when you bought them?  
The MC1991 is a hydraulic cam so lash shouldn't be an issue.
The cups on the rockers don't look galled but I have to ask, are you sure the top end is getting proper oiling?

That's awesome you tracked down the head info thank you! From what I've seen it has been oiling itself properly, The problems have been on cylinders 7 5 and 6 after install I took the motor out and the builder was supposed to replace the heads but that obviously didn't happen.. So, I should look at replacing springs pushrods and rockers.. Right now I've just got the GM stamped 1.5 which I've heard is actually closer to 1.46 and COMP cam is supposed to actually have 1.5 ratio rockers.. So stronger springs to handle the 465 lift? From what I've seen 465 is pretty mild isn't it? Thanks for all the info guys!

GM B-Body Forum wrote:If your running stock springs, i know those have a max lift of about .460 before some funky things start happening. It sounds like your pushrods are too long, or you are getting some serious coil bind. You running hyd lifters or solid? Did you preload or set the valve lash correctly? Are you using 1.6 rockers or stock 1.5?

Valve lash was set after install and I am using hydrolic lifters with stamped 1.5 rockers..

Hey guys! Just wanted to post an update! Albeit a very delayed one.. Turns out no one in the engine shop actually set the lifters before I received the motor for install and I know neither of the mechanics I was working with did either... So last October I replaced the rockers and push-rods keeping to stock 7.8" pushrods and 1.5 rockers, I reset all of the lifters by hand myself and had to replace my Alternator which had blown out (again, luckily that's under a lifetime warranty..) So the Caprice has been running great the last 7 months!! Aside from daily driving I have taken it on several inter-state drives and now that the lifters are actually set correctly the motor is running better than ever!! Oh and with the weather becoming so nice and the fact I'm actually going to have a garage of my own baby will be receiving a full Flat-black paint Job this Spring :] It's current paint scheme is Original Burgundy/Rust with a flat Black Hood and patches of Hazard Orange, Black and Rustomleum red ha ha

383Falcon wrote:Hey guys! Just wanted to post an update! Albeit a very delayed one.. Turns out no one in the engine shop actually set the lifters before I received the motor for install and I know neither of the mechanics I was working with did either... So last October I replaced the rockers and push-rods keeping to stock 7.8" pushrods and 1.5 rockers, I reset all of the lifters by hand myself and had to replace my Alternator which had blown out (again, luckily that's under a lifetime warranty..) So the Caprice has been running great the last 7 months!! Aside from daily driving I have taken it on several inter-state drives and now that the lifters are actually set correctly the motor is running better than ever!! Oh and with the weather becoming so nice and the fact I'm actually going to have a garage of my own baby will be receiving a full Flat-black paint Job this Spring :] It's current paint scheme is Original Burgundy/Rust with a flat Black Hood and patches of Hazard Orange, Black and Rustomleum red ha ha

It's good to hear that you've got the bugs worked out and she's running great for you.
Spring is right around the corner. Sounds like you're in for some fun times out cruising!

383Falcon wrote:Hey guys! Just wanted to post an update! Albeit a very delayed one.. Turns out no one in the engine shop actually set the lifters before I received the motor for install and I know neither of the mechanics I was working with did either... So last October I replaced the rockers and push-rods keeping to stock 7.8" pushrods and 1.5 rockers, I reset all of the lifters by hand myself and had to replace my Alternator which had blown out (again, luckily that's under a lifetime warranty..) So the Caprice has been running great the last 7 months!! Aside from daily driving I have taken it on several inter-state drives and now that the lifters are actually set correctly the motor is running better than ever!! Oh and with the weather becoming so nice and the fact I'm actually going to have a garage of my own baby will be receiving a full Flat-black paint Job this Spring :] It's current paint scheme is Original Burgundy/Rust with a flat Black Hood and patches of Hazard Orange, Black and Rustomleum red ha ha

I'll be looking forward to seeing you pass me on the I-5 with that machine!