[MagnumForceGB]

I got a set of MACE 210/210 camshafts for my LLT back in November. Over the winter time I removed the cylinder heads, ported the exhaust ports, installed 85 lb valve springs and the camshafts. I had my supercharger installed during the first drive but due to the impeller seal leaking I have it off and will be tuning it as NA. Next Friday I plan on going to the track with this setup, see how it works.

For the install, I did everything in my own home garage. Cylinder head removal wasn't required but I removed mine to replace my original ones. This also gave me a chance to port only the exhaust ports which I enlarged from 40mm wide to 46mm-47mm wide (forgot which). For the height I only went from 20mm to 23mm, but I slopped the ports down to where the gaskets were. The bottom of the exhaust ports were close to the top coolant ports, didn't want to destroy them. The exhaust valves are 30mm in diameter each, so both of them open flowed a lot and the stock exhaust port narrowed down fast. They now matched the gaskets, but are still smaller than what my ARH headers are height wise.

I did the valve springs with the cylinder heads off which made it easy. The stock valve springs are around 60#, going to 85# made the engine harder to start (it struggles a little bit now) but will make sure there is no valve float when I get into extreme RPM and boost.

For the camshafts themselves, they are about the same valve lift as the stock cams. The duration is about 25 degrees longer (getting the exact specs for OEM is hard) with the same centerline, this allows more overlap at rest position but earlier exhaust valve opening and later intake valve closing. This allowed more overlap at mid-range and extending the torque curve to very high RPM. These cams really shine when you rev the engine out, you can have 3.91 gears but still get the MPH of 3.27 gears. The install was straight forward, if you are doing timing chains yourself then to swap out camshafts is real simple since majority of the work is done (timing cover and chains removed).

The only issue I had during the whole install was during the first startup. I started the engine up and after 20 minutes I gave it some gas and everything when to crap. The engine started misfiring and bank 1 went completely lean. After a week of troubleshooting I found out the issue was a camshaft actuator solenoid had gone bad, it wasn't returning to the rest position so oil was constantly going to the movement side of the oil passage. Best way I can describe it is each camshaft has 2 oil passages in the cylinder head, they lead into the camshaft actuator itself. This solenoid controls which passage gets the oil, the advance or retard passage. My solenoid was stuck on the retard passage so the exhaust cam was 50 degrees closing the exhaust valves later, causing massive overlap on only one side of the engine.

I've driven the car for the past 2 days for my work commute and the mid-range acceleration is a lot better. The engine is currently revving to 7200 RPM and still making power, by next weekend I want to have it revving out to 7500+, depending on when the intake manifold stops make power. I'm using a crappy hot air intake setup from parts of my boost pipes for right now. The exhaust note became deeper with a little bit of lope, but nothing drastic. I'm still working on the off-idle acceleration, there is a little bit of lag in it.

Current mods are:
80mm Throttle Body
LFX Intake Manifold (ported throttle inlet)
MACE 210/210 Camshafts
MACE 85# Valve Springs
Ported Cylinder Head Exhaust Ports
American Racing Headers 1-3/4" Long Tube Headers
ARK DT-S 2-1/2" Cat-back exhaust
Circle D 5C Torque Converter
Driveshaft Shop 1-piece driveshaft
210mm Differential with 1LE 3.91 gears and JRE Posi-Mod
1LE Axles and Hubs
BMR Suspension
HP Tuners self-tuned

My car is still heavy since I have some of my supercharger stuff still on, mainly the intercooler and meth pumps. I'm hoping to get at least a low 13 second pass since the DA will probably be in the 2000 range.

Any questions about these camshafts, I can answer them like the install and some specs. These cams didn't not require a VVT delete or limiters, they still allow full range of movement. They do require the engine to be revved higher to take full advantage though.