intake manifolds

[aaklingler]

Did the intake manifolds change somewhere around 99? Did the diameter change? From what to what?

[1Dieselman]

Yes they changed middle 99 from I believe around 2" early 99 to 3" late 99

[late_99_PSD]

^^^Yup

[Patrick Feeley]

They also changed within the 2" versions (from 8-bolt to 10 bolt). I want to say mid-96 maybe? but I'd have to check. Cheers!

[backwoodsboy]

94.5-97 was a "Y-pipe" - directly off the turbo into the plenums.
99-99.5 was a "Spider" - from the turbo, to CAC, back to the plenums.
99.5-03 was a "Spider" - same design as 99-99.5, but 3" diamater as opposed to 2".

[aaklingler]

Thanks guys, Is there reason everybody wants the early spider for the obs trucks?

[late_99_PSD]

The early spider has the 2" outlets that match the OBS intake plenums. A 99.5+ spider would not match up.

[aaklingler]

unless you change the intake manifolds?

[backwoodsboy]

You'd have to put some 3" SD intake plenums on, as well as do a fuel bowl delete in order to run a L99-03 spider.

[Patrick Feeley]

The turbo flange is different as well (that's why the need for the early 99 spyder, it would mate up with our turbos). With the early 99 spyder you also need the boots that stepdown from 2-3/8" to 2" and a different turbo clamp. Cheers!