JGX421

The Car-

I recently picked up a 97 WS.6 Formula a4 for a decent price. It has 160k on the clock and is in really great shape cosmetically and mechanically.

As of now, it is mostly stock with the exception of msd wires/coil, 160 T-stat, eibach pro springs, hotchkis panhard bar, a flowmaster muffler, and is programmed with a hypertech III handheld programmer.

The Plan-

The route I want to go for this car is a reliable driver to enjoy on the street.

I want to carefully select a few performance parts, but want to keep the car as stock looking as I can, both exterior-wise and under the hood.

I am looking into getting the LE2 stock ported heads, LT headers, and a cam that, as of now, I am undecided.

I have a few things for the build already - stage 3 4l60e (3200 stall) built by Big Dawg Transmissions in Tampa, Fl - ported and polished stock intake (currently red, but will be sandblasted to it's natural finish to keep it looking true to stock) - I will be purchasing a 58 mm tb soon as well.

With the exception of not knowing what cam would be the best for me at this point, I do believe that the above upgrades will help me accomplish what I want for the car.

The Question-

My question is this; what will need to be done to the bottom end of this otherwise stock engine to keep it reliable? Should it be rebuilt? If so, what would need to be done to make sure it will be able to perform to the potential of the aforementioned upgrades and keep it reliable? A 160k mile engine seems that it may not be reliable with those new parts. Am I wrong?

I have a budget of 2-4.5k.

Any advice to pointing me in the right direction will be appreciated.

SS RRR

iTrader: (2)

Get a leakdown done. If cylinder pressure is not escaping from the bottom end and you still have good oil pressure then leave it alone. If it is then at the very least you will need a hone, rings and might as well put in new bearings all the way around. A machine shop can check the bores to see if you can still use the stock pistons without having to bore the cylinders out. On my stock block I did not have to get my cylinders bored and it had 95K miles before I spun a cam bearing (my own fault).

94FBIRD

iTrader: (5)

I would add, that if do hone, rings and bearings put in some ARP rod bolts and new standard pressure oil pump.

Catmaigne

iTrader: (6)

If it was mine I would hunt for a low mileage shortblock from a wrecked b-body or find a core for a near stock rebuild (hone cyls, polish crank, ARP rod bolts and resize, etc). You can build it outside of the car and swap it in when you're ready. The junker shortblock is the cheaper option but a proper rebuild with the right clearances will take more abuse (assuming the builder is competent).

BALLSS

OP

if getting LE heads have Lloyd spec a cam

160k....well what I have seen several times is guys putting H/C in motors with that and more mileage and not long after wiping a bearing, sometimes cam but usually rod or crank. You spin the motor at 6k+ and 160k old bearings just hate that

advice given on getting leak down is good. if you get away with a hone & ring job great but having the rods resized with APR fasteners is advised. polish crank and new bearings all around.

You can roll the dice and just do H/C....just not what I would do on a 150+k mi motor

SS RRR

iTrader: (2)

The only reason why a bearing would get wiped after a cam install is due to a careless, dirty install. It's no coincidence it happens when the oil pan acts like a catch all when the timing cover is off. I wouldn't worry about doing rod bolts unless you are planning on spinning the motor more than 6500rpm. When you do that you then compound the price due resizing the rods. Of course, this all depends on the well being of your oil pressure and cylinder pressure.
If you want to stay within a budget then this is my advice to you. Of course there are risks, but that's what happens once you start modifying.

Catmaigne

iTrader: (6)

160k is a lot of miles for OEM bearings. You also don't know the history of this motor (how hard it's been romped on, if it's been overheated, oil change frequency, how many cold starts, etc.) so it's a huge gamble. Don't plan on a setup like that lasting a long time, especially if you take it to the track. It's also foolish to think good oil pressure always correlates with bearing health. The production bearing clearances for these motors vary. If a clearance is on the tighter side then the chance of losing a bearing at high RPM is greater, especially when you're revving beyond the limiter of a stock motor.

The only reason ARPs are recommended is so you can get away without rebalancing. If OP wanted new pistons/crank then the obvious choice would be a 4340 rod with the cap screws already in them.

SS RRR

iTrader: (2)

Good point on the oil changing frequency. That can be determined by popping a valve cover and seeing how much sludge buildup there is. If it is an issue then it's best to just do a rebuild. I still disagree with messing with the rods since that can increase the cost exponentially.

Honestly if it were me I'd slap heads/cam on there if the the inside looked something like this:


Would not do so if it looked a little like this:

cuisinartvette

Yes and no you are on the right track
Sometimes cheap builds are the most expensive

JGX421

All of your input is appreciated. Reading through the posts here, I am inclined to think about completely rebuilding the bottom end before I install anything I mention earlier.

Going this route is going to require more time and funds though for sure, but I will feel a whole lot better knowing I won't be pushing an old engine beyond it's capability.

Not knowing the oil change history of the car was something I hadn't considered. Although the car was very, very well kept by the previous owner, I'm just not comfortable taking a chance like that.

So besides polishing the crank, new bearings, rings, and honing, what else should be considered for this build up? New oil pump? Rods were mentioned in the thread as well. What do I need to be concerned with as far as the rods go?

I do like the idea of finding a used shortblock and building it outside the car, but for this car being a ws6 and somewhat hard to find, I feel that not building and keeping the original block in the car would take away from it's originality.

Catmaigne

iTrader: (6)

Definitely wouldn't want to modify a sludgy motor but clean doesn't always mean it will survive. The inside of my motor was clean as hell with only 99k, had good oil pressure, and was well maintained but that didn't stop it from trashing bearings. Granted, it was a weekend car that was driven pretty hard at any given opportunity. Few trips to the track didn't help.

New oil pump would be a good idea. The Melling Select pumps have forged gears, stronger housings, and steel driveshafts (the regular pumps have thinner castings, cheap PM gears, and don't include a shaft). The 10554 is the best for a stock style rebuild because it's std volume but with a high pressure spring.

Rod bolts are a good idea if you're going with a decent sized cam. They will have to be resized.

I don't think a WS6 with 160k on the clock is really collectable. That and the WS6 package is more geared towards handling than anything else. The motor itself is unchanged from a regular TA/Z28 so nobody cares if the numbers match. The LT1 shortblocks from different years and platforms are nearly identical and any will make a good foundation for a build. There are 2 types of rods (forged in 92-94 and powdered metal [stronger] in 94-97), different cam snouts on non-vented/vent optis, and some sensors changed, but otherwise it's all the same.

You can always keep the original block as a spare. If your car works right now I'd leave the motor in it and build something else to swap in. That means less downtime.

BALLSS

your stock rods will be fine but I would have new ARP fasteners put on which will require them to be "re-sized" Machine shop will do this

as noted about the oil pump get the Melling Select one mentioned

LT1 blocks are pretty cheap $100-$200 or even less sometimes....you just need to get one that can be honed vs .030 bore requiring new pistons if you want to re-use your stock pistons. While you can visually see if there are any scuffs in the cyl holes and the cross hatch may "look" good you will have to have a machine shop mic & inspect it to see if it can just be cleaned up with a hone

SS RRR

iTrader: (2)

If you are wanting to rebuild the engine then why not slap heads/cam on the one you have until it blows up? The way I see it you've got nothing to lose.