stock LLY turbo inlet

Killerbee

Got Honey?
I would only be guessing, that he used the original to make a cast mold. From the crease seen at the bend, in Mikes pic above, the detail of the part looks identical to stock.

I will have to go get some pressure drop numbers to see what this restriction is really doing. From just measuring, the x-section goes from 8.3 in^2 to 5.3 in^2 (where there is a 90 degree razor sharp bend) then to 6.6 in^2.

For guys doing series twins, assuming 35 psi of boost, 4000 rpm, air flow is something like 1160 cfm. That restriction is flowing air at 360 mph around that 90 degree bend. Add the lack of (any) curvature to the inside of the turn, and that is going to be some serious drag.
 

LarryJewell

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Jan 21, 2007
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KB,
since it is made out of metal would it not be thinner,Hence less restrictive
like as you have seen the inside of the plastic is fairly thick especially at the corner
where is the metal wouldnt be.
IMO what we really need to do is get rid of the EGR motor for starters and then relocate the intake riser and modify the intake manifiold.
then we could run a way bigger turbo intake......Just a thought

My egr motor is already gone, I'm up for some testing...:D
 

Killerbee

Got Honey?
Simulations

Example with MAF=84 lb/min. These show the nasty characteristic, with losses over 4 psi. By getting rid of the of she sharp corners, ksi (small loss coefficient) is reduced, and with diameter increased, most of the drop will disappear.

For the last few years, for purposes of turbo calcs, I assumed intake losses to be around .5 psi total. WOW, was i wrong. This has a disastrous effect on PR when looking at the compressor map. A 2.4 PR, is actually 3.1. That would explain, at least in part, why the VVT compressor product is so darn hot, with toilet efficiency.
 

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codyn

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Aug 26, 2007
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yea the intake rise in the front that goes to both heads that piece comes out in front to piece that was conected to the intake pipe where the egr was bolted on we we made a different way to give there more room. i can get pics when we get the truck back
 

LarryJewell

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Jan 21, 2007
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So what are you doing KB, just using a dremal and shaving the inards on the corner bend

would we not be better to just use a bigger volume HOSE?? , The EGR riser seems to be the biggest problom for the room inbetween riser and intake into the turbo:(

That is someething else that im not to fond of, is the WHOLE intaker riser and "Y" manifold....but thats a whole other thread:D


Well Simon, How about a new thread on the intake riser and "Y" manifold ;) What can be done to improve that :)