I have the TR 230/224 111 LSA w/ stage 1.5 5.3 liter heads. I am interested in getting the magnuson running only 5 lbs of boost. Will I be alright? Thanks, Kaley

 

Kaley -

I'm certainly no expert, but it looks like nobody else jumped on this thread, so I'll make some observations based on the reading I've been doing on CF and LS1Tech.

Yes, the mag will "work", but your cam is definitely not ideal for a supercharger, especially one like the maggie, for a few reasons.

First, for forced induction, you want to keep the LSA wider (numerically higher), to reduce overlap and keep from blowing all your boost out the exhaust valves. 114 or greater is generally suggested by folks. Note the high separation and split pattern that LPE has on their GT2-3 cam.

From what folks have said, the Magnusson supercharger is pretty taxed up here at altitude, so a high overlap & duration cam would compound that problem.

Second, folks usually recommend a split pattern cam (i.e. 220/226 or 218/224, for example) for superchargers. This is because the supercharger provides lots of help to the intake side, and by biasing the cam towards the exhaust side, you can get the air back out in a more balanced fashion. With your TR227, and a supercharger, you'd have gobs of intake flow. But, with the lesser exhaust duration, and the exhaust port on the 5.3L heads that isn't as good as, say, an LS6 exhaust port, you're very biased towards the intake. As old drag racers would say "it can't eat because it can't crap"

Lastly, the high compression of your TEA 5.3L heads is at odds with forced induction. You'd perhaps want to go back to stock LS1 compression. It seems you wouldn't want to go a whole lot lower, since the magnusson simply can't move a whole lot of air to make up for a low compression engine.

Try calling around to some tuners up here in Denver/Ft. C etc, and get their opinions on forced induction at this altitude. I've had a few tell me they really like the mag, and a few that they think it simply can't breathe hard enough in our thin air.

In your position, not road racing the car, I'd go with the TTi system. That's what I'd do too, but nobody seems to have a way to retain any kind of brake ducting with it :cry . When you start adding up the cost of a Mag supercharger + hood + painting + headers etc, the TTi system starts to come out ahead in performance and price in a hurry. Plus, I don't think anybody would argue that turbochargers aren't a better mousetrap than blowers are. Or, I simply could be biased, from my knowledge/history with that GSX of mine.

Hope that helps!

-Jake
beginning to wonder if his C5 will ever be as fast as his DSM... :rolleyes:


[Modified by JakeL, 10:46 PM 10/23/2003]

 

Jake, I am living in Florida now. So the air here is not thin :). Antone else? Thanks, Kaley

 

Aside from the issue of altitude and thin air, his other points are right on. If you're set on the Magnusson as your next mod, I'd at least change the cam.

 

If I were to leave the cam in for a while will I risk damaging the motor? Thanks for the replies guys. Kaley

 

The high CR from the heads could be a problem, the cam won't cause any damage.

 

I have been told that if I run low boost I will not have a problem. That is why I am leaning towards the magnuson. I only want to run around 5 lbs. Anyone else? Kaley

 

Most likely, your cam with its relatively long duration and tight LSA has a fair amount of overlap. I do not know what compression ratio your heads are at but the overlap of the cam will help lower the compression and be less prone to detonation.

 

TEA has some nice 5.7 and 6.0 heads with stock size or larger chambers. I would look for a standard split cam maybe a 222/230 on a 114 or 115.