So I'm nearly complete with the engine swap, suspension rebuild, etc., covered in the previous thread:

https://www.corvetteforum.com/forums...post1593386188

A couple of followups.

I have about 500 miles on the car now since putting it back together. It runs great as near as I can tell, no CELs, no pending codes since two weeks ago. I probably have 30-40 start cycles on it.

The only outward mods I can see are the Borla exhaust. Its been a long time since I listened closely to a V8 but it sounded a little lumpy to me but that could be the exhaust. Not knowing the full history of the replacement engine I was thinking maybe valves or lifters...they sound a little tappy but could be normal. So I ran a compression check. I drove it around for a while enough to do a recheck on the transmission fluid level so engine was at operating temp. It took me about 45 minutes to get all plug wires and plugs out and compression check set up before first cyclinder (No. 2) so engine was still warm. Here are my numbers:

Cyl/Gauge PSIG
2=210
4=210
6=210
8=205
1=205
3=205
5=206
7=207

I removed all plugs and used 7 cranks each cylinder. At 5 cranks (if that is important) the reading was almost consistently about 10 psig below the above numbers. I used the OTC 5605 test kit. The engine has about 74k miles.

The first three readings are probably closer to the 205-210 range... I went and got my glasses after the first three b/c I was originally expecting a much wider range, turns out I needed a closer look.

I was planning to do a leak down test but abandoned the idea when I saw the above results. Think I'll just drive it and enjoy it.

I posted a picture of the plugs at 500 miles. Anyone care to guess which plug was the biggest PIA?

Pretty much all that is left is to wrap up the A/C. I'll be replacing the compressor and accumulator but wanted to do the compression test first. The only thing that isnt working right now is the lights on the top four gauge buttons on the right side of the display. The buttons work fine though.

Any thoughts on these numbers? I'm wondering if the lumpy sound is normal or possibly a previous owner swapped the cam. I dont get any misses on the firing.

I'm averaging 19 mpg as a Sunday driver. I've only gotten on it a couple of times. WOT sounds great with those exhausts.

 

Great to see you got it rolling. How are you liking it so far?

Ls1's are known to have noisy lifters. The fuel injectors also sound a little loud to me. Some of the earlier LS1's had piston slap and GM started using the LS6 pistons with coated skirts around 2001 (I believe). At least that is what mine had in it. Any exhaust noise can be heard from inside the cabin.

Our cars were made with hardly any sound deadening material so you hear everything.

The compression results look real good as far as cylinders being nearly identical. The pressure seems slightly high like there might be a little carbon build up. My old heads had a lot of carbon in the combustion chamber. The plugs are so new its hard to see anything. But if it has been modified it may have higher compression.

I got my A/C compressor new from amazon for $100 and it works fine. I got my condenser there to from Sunbelt Radiator near Miami. If you are running headers you might want to wrap or re-rout the lower ac line and use a starter shield.

If you have carbon in the combustion chamber you can run some sea foam through the engine to clean out any carbon and run premium fuel.

If you are curious about weather or not it had a cam swap, you could always measure it's lift from the top of the push rods by removing a valve cover. If the heads have been swapped then that might be some indication of someone having done performance mods. If this is the case then you will want your PCM tuned to match the mods. What is the casting number on the head? You may have an engine with 100 more HP and not realize it. You may have a LS6 engine.

 

How are you liking the poly bushings. I skipped this step when I had my suspension apart thinking the rubber ones were fine. Now I am regretting it. On the highway, the car is out of control if there are any bumps. Nothing like doing things twice.

I replaced everything else as you did in your build. I'm assuming the rubber bushings got soft with age and now every bump sends the wheels a few degrees out of alignment in every possible direction. When I had it aligned, the shop had to max out the adjusters and still had some negative camber and too much caster (a sign of bad bushings).

Secondly, how hard was it for you to make the swap?

 

I'll have to check the heads. Now that I'm nearly done I'll be taking it to vettexperts nearby to check the tune, particularly for south Florida. I'm actually just starting my second tank of premium gas/seafoam added and I think the idle is cleaning up a little. Its actually smooth but just a little jumpy sounding. Now that I have dissected the old engine I know where everything is so I'll check. Thanks. I went for stock OEM on everything but now having dismantled the old engine I would be comfortable with doing upgrades. When I replaced the harmonic balancer the old one appeared to be the stock OEM....doubtful someone would put that much into the engine and not upgrade the pulley but who knows. I do think at least one of the heads have been removed on this car looking at the area around the gasket.

I'm completely happy with the polyurethane. The original rubber didn't look bad but there were two squeaks somewhere and I've been down that road before so I replaced them. It is a chore though. Probably the most tedious part of the rebuild. I have new OEM shocks and the ride feels balanced. My other project weekend drive for the past several years is an older 911 so the C5 actually feels fine with the stiffer bushings by comparison. The C5 does stick to the road though. It was eye-opening after the alignment. After installing the new suspension I put the obligatory 100 miles or so on it before alignment. It was all over the place. After they did the alignment and restored the ride height the difference was night and day.

The swap is not that difficult once you do a few of them and get the technique down. There's just a lot of them! I did all control arms...including the sway bar bushings. I used a combination of propane torch, vise, my cheap 12-ton press from HF, and a balljoint press set. You probably dont need all of that but I just had them available. I relied on several available threads and a video or two and doped it out from there.

 

Saw your thread with the pics of the damage to the old engine.

Best of luck getting the new engine installed and the car back on the road.

 

I hear the HF 12 ton press is a good value. It would be useful for other projects. I tried to get mechanics to do my bushings and no one will touch it.

Thanks for the info.

 

The 12-ton has worked well for me....I've done many wheel bearing replacements, ball joints, etc., and it worked fine. If I had to get another one I would likely go with the 20-ton, only b/c the frame is a little stiffer, not for lack of power. The 12 flexes a little and makes alignment challenging sometimes, but still works fine. For bushings the 12 will be no problem. A nice assortment of different thickness scrap steel plates is great for leveling and shimming work pieces.