Magnuson 1900 Project- over-drive Cog, Porting, & Cutting out restrictions....

[G8-4-Speed]

Today started a 1900 project to see what porting and over-driving a 1900 will change. What originally started as a Cog upgrade, ended up as "while we have the blower off......" type project. Today was tear-down, port, and add the cog drive. Well, the cog drive wasn't the bolt-on we had planned. Turns out the 1900 is a older style with press-on hubs that need the bolt-on flanges pressed on first before we can upgrade to the cog-drive. On to the porting.... The ports on the lower blower manifold are a bit tiny when compared to the head. How tiny? Tiny enough that the 1 1/2" port length cuts off almost 50 cfm at high lift.
Flow cfm with the stock manifold bolted to a mildly ported head are:
stock ported
.300-202.4 217.9 +15.5
.400-236.3 259.5 +23.2
.500-257.7 294.2 +36.5
.600-268.1 315.3 +47.2
.700-273.3 322.3 +49.0

It is pretty sad when a manifold runner, as short as it is, cuts off that much flow.

***If you have ever taken a blower manifold apart before after 30,000 miles, this is as clean as they get!!! usually they are caked up sludge and puddled with oil. Methanol injection rocks!

Next, ported a throttle body....
And adding a 4" LS7 card style MAF...
Installing a second 325cc methanol nozzle.....

This is DougH G8 with a DoD cam pushing 10psi. We'll see where it ends up at when its all done....

[evl.346]

very interesting
did you just die-grind the runners to match?
what kind of benefits or gains are you expecting.

will be good to see the final outcome and gains you make aswell

while its open any chance of a pic of the intercooler core?

cheers

[locrzn#92]

I like.

[GXPaycheck]

Like Doug isn't fast enough as it is!

Looking forward to the finished product.

[G8-4-Speed]

We are trying to keep the boost down and make more power with the cog. Would guess 12psi with the Cog but if it was 10, even better. Just trying to flow air more efficiently.

[G8-4-Speed]

very interesting
did you just die-grind the runners to match?
what kind of benefits or gains are you expecting.

will be good to see the final outcome and gains you make aswell

while its open any chance of a pic of the intercooler core?

cheers

Would guess it should pick up 15-30 hp just from the porting. Yes, used the gaskets to get a port location on the heads and then matched it to the intake. I have several special cutting bits for aluminum and spent most of the day working the intake and throttle body. Will load a picture later of the intercooler.

[Darkmanx]

I'm @ 650 @ 10psi so its not hard as is

[hartigan85]

I can't wait to see the difference this makes. I've been wanting to port the blower since I installed it and saw the size of the ports. Seems ridiculous to me that Magnuson would make the ports so small and odd shaped.

Can you do a write up for tearing the blower down to that point?

[Doug Hilliard]

Thanks for the pics and update Rick; man those flow gains are pretty amazing! Hate we got snagged on the pulley/shaft issue but I'll get the new hubs on order tomorrow!

[SpeedRacerX]

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