Jean's Turbo Build - 318TTi

[trikzta]

how do you know if you have a Dinan TB besides the Dinan Readin inside of it

[Jean H.318TI]

Idk I guess the only way to know is by looking inside

[ChItalian1027]

Jean, that is a massive TB ! glad your working again ! why are there two flaps on the TB?

[Jean H.318TI]

pretty sure the small flap is for the idle but im not 100% sure

[UberWagen]

Originally Posted by ChItalian1027

why are there two flaps on the TB?

My Old Scirocco is like that. The book said it was something to do with maintaining port velocity on take off.

[ChItalian1027]

Originally Posted by UberWagen

My Old Scirocco is like that. The book said it was something to do with maintaining port velocity on take off.

Ok, I thought it was strange that there are two flaps

[sokat1989]

Originally Posted by ChItalian1027

Ok, I thought it was strange that there are two flaps

If you mean 2 butterfly valves then you should know that the stock throttle body has 2 as well.

[ChItalian1027]

Originally Posted by sokat1989

If you mean 2 butterfly valves then you should know that the stock throttle body has 2 as well.

haha, thanks Sohaib

[pdxmotorhead]

If you remember the Zr1 corvette, or the Z28 IROC both exploited a system using dual intake paths to "tune" the intake for the engine RPM.

The throttle body is a progressive design, it uses the small throttle plate for off idle and low throttle settings the bigger one for better heavy throttle performance, internally the intake has a valve that changes the length of the runners long for low RPM torque and short for high rpm HP. Its a lower tech and cost alternative to variable valve timing. (Vanos) that's very effective, on the ZR1 it was as much as 150HP difference with it turned on or off depending on what you did with the engine management.

The 318 actually was pretty respectable in the early 90's not many 1.8 liter engines broke the 125HP mark.

Dave

[Jean H.318TI]

mine broke that mark too 1.9 liter with 130whp

[ChItalian1027]

Originally Posted by pdxmotorhead

If you remember the Zr1 corvette, or the Z28 IROC both exploited a system using dual intake paths to "tune" the intake for the engine RPM.

The throttle body is a progressive design, it uses the small throttle plate for off idle and low throttle settings the bigger one for better heavy throttle performance, internally the intake has a valve that changes the length of the runners long for low RPM torque and short for high rpm HP. Its a lower tech and cost alternative to variable valve timing. (Vanos) that's very effective, on the ZR1 it was as much as 150HP difference with it turned on or off depending on what you did with the engine management.

The 318 actually was pretty respectable in the early 90's not many 1.8 liter engines broke the 125HP mark.

Dave

Thanks Dave for explaining this to me, I didn't know that the 318s came with the dual plate TB

[pdxmotorhead]

The dinan one has been made cleaner, and I believe has a larger secondary bore, be nice if someone that has both would measure them and document them before they install it....

Dave

[Jean H.318TI]

ill do it once i get my DINAN on the mail

[pdxmotorhead]

If you can,,, use a good caliper and check:

1. Both Bore Diameter
2. Throttle plate thickness
3. Rod diameter for both throttle plates
4. Length of throttle body from entry to exit.
5. difference in bore entry and exit
6. Pics from top and bottom and sides if you can!

Thanks!
Dave

[Jean H.318TI]

idk if i can get all those numbers but ill try my best