OK, been a while since I updated. Yanked the monster apart this january. It was literally leaking from every gasket and seal possible.head gasket, rings, front/rear seals, valve covers, oil pan, timing cover,etc.... Here's the nasty old engine before I got it out:
So much crap in the intake it was ridiculous. Got the engine torn down and found 3 broken pistons, and all 8 intake valves had the keepers so loose it should have dropped a valve. So had the heads milled, new intake valves, cut the exhaust, 3 angle valve job, bored the block.030 over, decked, polished the crank, popped in a new Comp Cams cam with .500/.510 lift, new valve springs, miniram intake, 24lb accel injectors, hedman headers etc. So today I put her together:
Still need to drop the headers off at Pro-Kote and tomorrow I'll drop in the lifters, bolt down the oil pan and install the pushrods and rocker arms and then yank the rack out and get it rebuilt this week.
Also got all 4 new front control arms with newbushings and balljoints, So the suspension is now all new ( I rebuilt the rear last winter).
So the goal is to stab the engine and trans back in the car next weekend and get the plumbing finished up.Got new braided lines for hte fuel feed and return to the mini-ram and a new braided clutch line. Replacing the clutch, pressure plate, flywheel,master and slave as well. This thing should be good to go for a few years.
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Looking good! I'm hoping I'll be able to start a similar build thread for my car soon! Hopefully all the weather dies down before it gets to Tulsa tonight.
Keep it up!
Got pictures of those pistons? That is something I would like to see
I took pictures of them with the phone and the wife deleted them by accident. Three where missing the inside bottom of the skirt. I found a ton of the pieces in the pan and oil pump pickup. It was pretty nasty. It was funny though, the deeper I tore this thing down the more amazed I was that it actually ran at all, let alone made enough power to be an over steering demon able to get sideways at a moments noticed with a touch of the throttle.
I discover to mention that the compression got bumped from the stock 9.5:1 to approximately 10.5:1 with the new pistons. I'm hoping to squeeze 290-300hp to the rear wheels out of it and have a real rev range that will allow me to shift at 6k instead of the L98's 4500-5k limit.
Very interested in this build, I like the C4s, and my parents own a '94 in Admiral Blue (LT1, 6 speed)...
A Corvette is on the bucket list, and a C4 is the first generation I'd really be interested in...
cool stuff. i really really want to put a 6 speed in mine. i'm contemplating just putting it down for 4 years and going through everything bumper to bumper. in 4 years i'll be emissions exempt and hopefully have enough $ for a cage and 6.2/t56 type combo. now that my belair and my impala are faster than the vette, i haven't felt the need to bother paying for registration let alone driving it.
I want to ditch the 4+3 trans for a tremec. But I don't have that extra $3k laying around for the swap kit. I'm thinking 2 years will be the time for that.
Bobzilla wrote:
It was funny though, the deeper I tore this thing down the more amazed I was that it actually ran at all, let alone made enough power to be an over steering demon able to get sideways at a moments noticed with a touch of the throttle.
You know what they say about small block Chevy engines, they'll run longer badly than most motors will run at all. Good stuff!
Javelin wrote:
Bobzilla wrote:
It was funny though, the deeper I tore this thing down the more amazed I was that it actually ran at all, let alone made enough power to be an over steering demon able to get sideways at a moments noticed with a touch of the throttle.
You know what they say about small block Chevy engines, they'll run longer badly than most motors will run at all. Good stuff!
Yes, absolutely. I enjoyed my C4 for years. L98 low end torque is great!
Ian F
UberDork
4/16/12 12:47 a.m.
Threads like this one really make me want to inquire about a flooded C4 sitting in a driveway I pass on the way to/from work every day...
You know the one thing I love about the c4 is its ability to hang the tail out but be completely controllable. I think sitting at the rear wheel lets you feel it sooner to catch it. That and the "insta-torque" the L98 gives. I'm giving up a little bit of that with the mini ram, but what I gain in usable Rome more than makes up for it.
Bobzilla wrote:
I discover to mention that the compression got bumped from the stock 9.5:1 to approximately 10.5:1 with the new pistons. I'm hoping to squeeze 290-300hp to the rear wheels out of it and have a real rev range that will allow me to shift at 6k instead of the L98's 4500-5k limit.
Is that much power really possible with a TPI intake manifold? Have you considered an LT1 intake swap to loose those mega long runners?
Adrian_Thompson wrote:
Bobzilla wrote:
I discover to mention that the compression got bumped from the stock 9.5:1 to approximately 10.5:1 with the new pistons. I'm hoping to squeeze 290-300hp to the rear wheels out of it and have a real rev range that will allow me to shift at 6k instead of the L98's 4500-5k limit.
Is that much power really possible with a TPI intake manifold? Have you considered an LT1 intake swap to loose those mega long runners?
Actualy I may have just answered my own question. You said too the rear wheels, not at the rear wheels. That's a big difference.
Bobzilla wrote:
You know the one thing I love about the c4 is its ability to hang the tail out but be completely controllable. I think sitting at the rear wheel lets you feel it sooner to catch it. That and the "insta-torque" the L98 gives. I'm giving up a little bit of that with the mini ram, but what I gain in usable Rome more than makes up for it.
You must be a talented driver. For the most part when I had mine if the tail stepped out, I was backing it into something.
He's got a miniram intake manifold. 
92CelicaHalfTrac wrote:
He's got a miniram intake manifold.
Doh, didn't see that, I saw in the 1st pic prior to re-build it still had a TPI.
daytonaer wrote:
Bobzilla wrote:
You know the one thing I love about the c4 is its ability to hang the tail out but be completely controllable. I think sitting at the rear wheel lets you feel it sooner to catch it. That and the "insta-torque" the L98 gives. I'm giving up a little bit of that with the mini ram, but what I gain in usable Rome more than makes up for it.
You must be a talented driver. For the most part when I had mine if the tail stepped out, I was backing it into something.
Maybe there was something "not quite right" with the setup? I found my C4 extremely easy to toss around: very well balanced and easy to catch.
njansenv wrote:
daytonaer wrote:
Bobzilla wrote:
You know the one thing I love about the c4 is its ability to hang the tail out but be completely controllable. I think sitting at the rear wheel lets you feel it sooner to catch it. That and the "insta-torque" the L98 gives. I'm giving up a little bit of that with the mini ram, but what I gain in usable Rome more than makes up for it.
You must be a talented driver. For the most part when I had mine if the tail stepped out, I was backing it into something.
Maybe there was something "not quite right" with the setup? I found my C4 extremely easy to toss around: very well balanced and easy to catch.
This. Pre-suspension rebuild and alignment the car wouldswap ends faster than a bucking bronco on Cocaine. After I rebuilt the rear end, and got the front pointed straight it became very manageable. there are so many bushings in the rear that a few of them getting sloppy makes for an interesting mess.
And yes, I swapped to a miniram and bigger cam with appropriately sized injectors. ~300rwhp is about all you can really get out of a massaged TPI set up. To do that requires T/B, siamesed tubes, big mouth intake along with the right cam and exhaust. But you still run into limited rpm range. Being that I am an auto-x'er, being able to get 70mph out of second gear is a good thing!
Got the rack out this morning. I swear that it cannot be possible with the engine in the car. Dropped the headers off to get coated.
ANYONE know what to do with the old TPI setup? I always thought that engine should have been in a motorhome with teh amount of torque it made from idle to redline.
lots of tbi truck guys swap to it, or used to anyway.
i sold mine to a guy on here with all the g body cutlasses when i went with the superram, then i ditched that, sold it for around $1300, and plopped on a single plane and a carb and it pulls hard to 6k. such an unreal difference over the TPI.
daytonaer wrote:
You must be a talented driver. For the most part when I had mine if the tail stepped out, I was backing it into something.
How old are your tires? Corvettes usually get limited miles, so often the rubber on them is much older than you would guess by the tread depth. When I bought my '92 Mustang GT, it had ancient Goodyear Gatorbacks that were rock hard and contributed to the worst snap oversteer in the wet I've ever experienced. Switching to new tires solved that issue with no other changes...
WELL, The rack is done. headers should be done Weds. Still need to get the p/s pump and the pressure hose ordered through Advance.
