[Steve91T]

Man I'm excited. Dailydriver posted his car for sale and I could tell from that add that it was much loved and well taken care of. Unfortunately a nasty knock on the engine forced him to sell it. I thought this could be the perfect car for my dad.

This car looks amazing for having 172k miles. It is pretty rare to find a 1 owner car these days.

So, first things first. I had the car for all of 30 seconds before I broke it. I dragged the exhaust pulling into my driveway and separated the car back from the y pipe. So today I fixed that so the exhaust wasn't dragging on the ground anymore. Next, I need to make room for all the parts Dave packed into the car. It's completely full of parts. Thanks Dave! And finally, I need to figure out what's up with the engine. It has a nasty knock. It has great oil pressure, runs smooth, no smoke, but knocks really bad. I think it's a lifter, but I don't know. I think I'm going to pull the valve covers and see what I find. As well as this car has been taken care of, I'm hoping the engine is healty. I'd love to just replace some lifters and let my dad enjoy this car for a while.

Anyway, let me know what you guys would do to diagnose this knock.


https://youtu.be/AJUsOvgpnmg

https://youtu.be/otobYePJLyo

[JimMueller]

LS1/LS6/LS7's/shorties/midlengths/longtubes in that order should flow the best. They'll all bolt up to the heads, but from what I've read only the LS1 F-body manifolds will be compatible with the F-body engine bay and suspension without hacking. The LS6 exhaust manifolds were only available for the Corvette, and the LS7 manifolds exit in the center instead of the rear like stock. From a performance perspective I'd not bother with shorties or midlengths, though.

Whomever you contact regarding a replacement cam, inquire about valve springs and whether your current length pushrods are the correct length. They may want to know what lifter you're using also. Ideally, you would use a pushrod length checker after everything is assembled to determine a pushrod length in the preload window, and order that length instead of assuming up front.

If you stick with stock exhaust manifolds now, realize you'll need to have the car tuned once for the stock manifolds and again after adding headers. A cam designed for stock manifolds will not be optimal for headers, and vice versa. So you will be making a compromise unless you decide to swap to another cam at the same time you install the headers. Ground clearance with longtube's should be fine at stock ride height but you would need to keep an eye on it if you lower the vehicle, or if your front suspension is soft enough to allow the front to 'crash' down after going over a speed bump which would hit the collectors on a speed bump. The y-pipes for longtubes are hit'n'miss, my ARH fit really well though.

[Steve91T]

LS1/LS6/LS7's/shorties/midlengths/longtubes in that order should flow the best. They'll all bolt up to the heads, but from what I've read only the LS1 F-body manifolds will be compatible with the F-body engine bay and suspension without hacking. The LS6 exhaust manifolds were only available for the Corvette, and the LS7 manifolds exit in the center instead of the rear like stock. From a performance perspective I'd not bother with shorties or midlengths, though.

Whomever you contact regarding a replacement cam, inquire about valve springs and whether your current length pushrods are the correct length. They may want to know what lifter you're using also. Ideally, you would use a pushrod length checker after everything is assembled to determine a pushrod length in the preload window, and order that length instead of assuming up front.

If you stick with stock exhaust manifolds now, realize you'll need to have the car tuned once for the stock manifolds and again after adding headers. A cam designed for stock manifolds will not be optimal for headers, and vice versa. So you will be making a compromise unless you decide to swap to another cam at the same time you install the headers. Ground clearance with longtube's should be fine at stock ride height but you would need to keep an eye on it if you lower the vehicle, or if your front suspension is soft enough to allow the front to 'crash' down after going over a speed bump which would hit the collectors on a speed bump. The y-pipes for longtubes are hit'n'miss, my ARH fit really well though.

I think there is a difference between LS1 manifolds. The 98-00 and the 01-02. I'm not 100% sure though.

This car is on coil overs and it's going to sit pretty low. Not slammed, but lower than stock. I just know he doesn't want to deal with long tubes. Another thing he really wants is low end torque. I don't know if long tubes compromise low torque.

I'm going to get an LS6 intake manifold. The PO already has a larger TB, so that should be a nice compliment to the ls6 manifold. Maybe I'm wrong, but with an LS6 cam, or something comparable, the cam might be the limiting factor, but the manifolds. Now for those who put a big cam, yeah I could totally see the manifolds being a problem.

Maybe it's just hopeful thinking.