[ZLBlue]

I'm happy to finally have the chance to start the Magnuson 2650 build soon on my ZL1. With Oil Pump being replaced with the revised part at the same garage I'm doing my build, I decided the engine might as well come out since both pulleys are being changed.

I was juggling the idea of having the build paired with a Cam only, but some camaro buddies in my community suggested since the engine is coming out, might as well do Ported heads due to the labor.

Since this is going to be a car used for Road Racing (every weekend possibly) and Time Attack events with rare use on the street with some long distance drive rallies, is it worthwhile to have a Cam and Ported heads added in? Or just the Cam?

Edit for list of mods:

- 2650 Magnuson Blower with 80mm upper
- 1 7/8 ARH headers (catless)
- ATI Harmonic balancer/ Lower pulley
- Ron Davis Heat Exchanger
- Stage II Cam package
- Nick Williams 103mm TB
- Big Gulp RotoFab intake (Oiled)
- Elite engineering oil catch can
- JMS Fuel Pump Voltage Booster V2
- Taylor spark plug wires and NGK TR7IX Iridium spark plugs
- Unlocked TCM
- Revised GM Oil Pump and new seals/gaskets.

[UFDUB]

Cam + maggy 2650 and supporting mods is fine for road racing/track work. Just don’t try to add a pulley to increase the boost. More boost = more heat which will decrease reliability and consistency when racing. The marginal gain is not worth the trade off. Making the engine more efficient (better supercharger, headers, less restrictive intake, cam with better fuel lobe) will give you plenty of power without affecting your ability to track it.

[UFDUB]

As long as your lower pulley/balancer is not larger (which over drives the supercharger), you should get near stock boost levels and a cooler charge compared to stock.

[Markoz28]

Not much to gain with ported heads. Going with an 80mm pulley on the Mag will bring boost up from what I’ve seen. It’s good to go with an ATI balancer but don’t increase the pulley size since the 80mm upper will increase boost anyway. You’ll probably be at 16psi. On that SC that is a very safe level with no heat issues. You could go more boost but you will certainly run out of fuel.

I’m sure with your combo and don’t forget the low side fuel, you should be about 850whp.

[UFDUB]

Yes, with cam, not heads. You need the cam for its performance and for its fueling. Don’t skip this.

[Markoz28]

It’s not that the engine cannot handle more boost. It’s that you don’t have the fuel to support a lot of boost. The cam is a huge help in fueling and the low side pump or voltage booster is a great addition. Even with those 2 things you are limited to how my fuel it can support. This is why ppl go with methanol as it is cheap and easy for fuel usage.

Besides going with meth or expensive pumps and injectors I think you will be more than happy at just 850whp.

[UFDUB]

More than a horsepower target, when the goal is track work, aim for reliable and consistent power that won’t overheat. That’s why suggested making your engine an as efficient air pump as possible, ie remove restrictions and use a better supercharger with better cooling, but don’t try to increase boost since this always adds heat. Good air intake, 103 throttle body, good supercharger, cam, and headers will get you a strong, reliable, yet cool running engine that you can track all day. All the power you need! More than power, you’ll need tires for much track work! Enjoy.

[travislambert]

I have a Magnuson 2650 and I can tell you from first-hand experience (with data), that you will never be able to keep that car cool or supplied with fuel without some serious supporting mods.

For a little background on my car... I have a stock lower, 90mm upper, big gulp, Nick Williams 103mm, cat deletes, and. JMS voltage booster. It dynoed at a little over 700 RWHP.

I'm having trouble keeping my temps down on hot days. My oil temps exceed 290F. My coolant temps are going above 240F. Unfortunately, there isn't much in terms of cooling upgrades available. Most of the products you see with "thicker cores" are snake oil. It just ends up increasing the pressure in front of the radiators instead of helping to cool. The increased mass of these units will help on the drag strip, but not the road course. I've actually been talking back and forth with the engineers at C&R Racing about a cooling solution. They told me straight up that their $1,200 radiator is no better than stock for road course.

If I could get the oil temps down, I think everything else would fall into place. In addition to C&R, I've talked to Improved Racing, Derale, Mishimoto, and others and nobody has a good kit available.

Last week I ordered a 95 mm pulley to drop the boost level and lower temps that way.

Fuel is another big problem for these cars. Sure there are plenty of "solutions", but basically none of them will work out of the box for road course use unless you keep things modest and go with a voltage booster only. Voltage booster will only get you to 700 RWHP reliably. Beyond that, you can run the engine lean.

The problem is we have a saddle style fuel tank. When you drop below 1/2 tank, and you go around a hard right turn, all of the fuel transfers to the left tank. Aside from a booster, none of the aftermarket solutions I've seen will keep up with fuel demand under this condition. The aux pumps like the junk DSX Tuning kit only taps the right side of the tank, so that's only a good option if you're eager to blow your engine. The Fore Innovations units delete the fuel bucket from the pump and therefore cannot provide constant pressure as the fuel sloshes around in the tank (because there is no buffer). Other units are pretty much variants of these solutions...designed for drag racing...not road racing. To my knowledge there are no reliable road racing lowside fuel solutions for more than 700 RWHP aside from a custom solution with a surge tank.

If you are serious about tracking the car in the heat, I think you'll need to dial back your build quite a bit to have a reliable setup.

[UFDUB]

I will say, for further reliability, ported heads with new springs/valves, trunion upgrade, DOD delete, and new roller lifter (ls7 style I think) will increase reliability with everything considered, however will likely not add much power. But if you’re already there, like ultimate reliability, and have the means to do, not a bad upgrade.

[Juiced1]

With your first build listed you're going to make a lot of boost. As long as you take care of your fuel system you should be fine but that's going to be a LOT of power for a track. Make sure those brakes are working. These 2650s do run nice and cool so you shouldn't have to worry about intake temps as much.

[swisstyphoon]

Originally Posted by travislambert

I have a Magnuson 2650 and I can tell you from first-hand experience (with data), that you will never be able to keep that car cool or supplied with fuel without some serious supporting mods.

For a little background on my car... I have a stock lower, 90mm upper, big gulp, Nick Williams 103mm, cat deletes, and. JMS voltage booster. It dynoed at a little over 700 RWHP.

I'm having trouble keeping my temps down on hot days. My oil temps exceed 290F. My coolant temps are going above 240F. Unfortunately, there isn't much in terms of cooling upgrades available. Most of the products you see with "thicker cores" are snake oil. It just ends up increasing the pressure in front of the radiators instead of helping to cool. The increased mass of these units will help on the drag strip, but not the road course. I've actually been talking back and forth with the engineers at C&R Racing about a cooling solution. They told me straight up that their $1,200 radiator is no better than stock for road course.

If I could get the oil temps down, I think everything else would fall into place. In addition to C&R, I've talked to Improved Racing, Derale, Mishimoto, and others and nobody has a good kit available.

Last week I ordered a 95 mm pulley to drop the boost level and lower temps that way.

Fuel is another big problem for these cars. Sure there are plenty of "solutions", but basically none of them will work out of the box for road course use unless you keep things modest and go with a voltage booster only. Voltage booster will only get you to 700 RWHP reliably. Beyond that, you can run the engine lean.

The problem is we have a saddle style fuel tank. When you drop below 1/2 tank, and you go around a hard right turn, all of the fuel transfers to the left tank. Aside from a booster, none of the aftermarket solutions I've seen will keep up with fuel demand under this condition. The aux pumps like the junk DSX Tuning kit only taps the right side of the tank, so that's only a good option if you're eager to blow your engine. The Fore Innovations units delete the fuel bucket from the pump and therefore cannot provide constant pressure as the fuel sloshes around in the tank (because there is no buffer). Other units are pretty much variants of these solutions...designed for drag racing...not road racing. To my knowledge there are no reliable road racing lowside fuel solutions for more than 700 RWHP aside from a custom solution with a surge tank.

If you are serious about tracking the car in the heat, I think you'll need to dial back your build quite a bit to have a reliable setup.

Maybe Improved racing can help you with an oil cooler.
I saw this video the other day:
https://m.youtube.com/watch?v=k2UeXr...ture=emb_title

[travislambert]

Originally Posted by swisstyphoon

Maybe Improved racing can help you with an oil cooler.
I saw this video the other day:
https://m.youtube.com/watch?v=k2UeXr...ture=emb_title

Thank you!

Yeah, I've actually been working with them on a (less-invasive) supplemental oil cooler setup. Michael is very knowledgeable and just an all-around top-notch guy to work with. His custom products are very high quality.

I didn't like the idea of adding another cooler layer to the front so I'm going to try to mount a small supplemental cooler with an electric fan the in area of the transmission. I have a manual transmission, so there's a little bit of room to work with there.

I have a 3-day track event starting on the 31st. If the parts arrive in time, hopefully I can get it installed and have some data.

[Bow Tie Fanatic]

Originally Posted by travislambert

Thank you!

Yeah, I've actually been working with them on a (less-invasive) supplemental oil cooler setup. Michael is very knowledgeable and just an all-around top-notch guy to work with. His custom products are very high quality.

I didn't like the idea of adding another cooler layer to the front so I'm going to try to mount a small supplemental cooler with an electric fan the in area of the transmission. I have a manual transmission, so there's a little bit of room to work with there.

I have a 3-day track event starting on the 31st. If the parts arrive in time, hopefully I can get it installed and have some data.

Thanks for posting your VIR PDR video. Is Chin in Oct still the plan? Good luck with the oil cooler.

[travislambert]

Originally Posted by Bow Tie Fanatic

Thanks for posting your VIR PDR video. Is Chin in Oct still the plan? Good luck with the oil cooler.

Yeah, I plan to attend VIR in the fall with Chin. I'll be at PittRace at several events in the meantime as well.

I'm the type of guy who will work until I solve a problem, so I'm sure I get something figured out with the cooling.