Throttle in front of turbo?

[Trojaneagle]

I have seen some old pics of an old chevy with the throttle body in front of the compressor intake.
Would this make sense today to prevent surge or will the air reading be inaccurate?
has anybody tried this before?

 

[Ric]

It's called draw thru.

Very old school turbo carburated engines. Not worth a shit now a days.

 

[Trojaneagle]

It's called draw thru.

yeah, any ideas if it'll work nowadays?

 

[Ric]

Nope. Blow thru is way more efficient and easier to manage and tune.

 

[Trojaneagle]

can you explain why it's more efficient? does the computer not get the correct info?

 

[Ric]

It's not even worth explaining.. that train of thought was dropped a many years ago, probably before you were born. Google it.

 

[tissimo]

My old drag turbo lebaron had the throttle infront of the turbo from the factory.. it leaked oil from the compressor seal due to the vac on the system.. but worked ok I guess.. I got a 14.7 at 93 on it w/ 18-19 psi and no intercooler.. lol..

 

[Ric]

haha I LOVE turbo dodges!! I had a 88 shelby Z 5spd a few years ago, i never got to make a pass at the track with it, but it was ghetto upgraded and i super gutted it and made it light weight. Im sure i coulda got 13s out of it.

 

[rumptis]

I haven't seen much of or any information about changing your AFM to blow through. Any benefits or negatives of that type of setup?

 

[mattjk]

was very popular on aircooled vw turbo kits with weber or dell'orto carbs.

 

[Ric]

Its a semi popular mod for grand nationals. LS1 MAF converted to blow thru.

 

[Supracentral]

I haven't seen much of or any information about changing your AFM to blow through. Any benefits or negatives of that type of setup?

Think about it this way. If you are going to re-engineer the car that much, why not get the restrictive MAF/AFM out of the way completely?

Blow through doesn't work well for our cars at all.

 

[Ric]

Think about it this way. If you are going to re-engineer the car that much, why not get the restrictive MAF/AFM out of the way completely?

Blow through doesn't work well for our cars at all.

Seriously. If your going to do that much work, just remove the MAF/AFM and get a MAP ECU

 

[rumptis]

I have no intentions on even trying this, the thread just got me thinking about it. I haven't hardly seen any info on it so figured I would just bring it up as its interesting just like putting the carb/TB in from of the turbo....even if it does suck.

 

[Ric]

It doesn't technically suck, the pistons create a vacuum and air tries to rush in and fill the void

 

[Doward]

Seriously. If your going to do that much work, just remove the MAF/AFM and get a MAFT-Pro

Fixed

Draw through CARB systems (Which is what you have in that pic) do not work well, because the fuel is suspended in the air, and it must all be compressed and driven through the turbo. The problem you have, is fuel will drop out of suspension and pool in the turbo, giving you erratic AFRs.

It really is a very poor setup. The blow through turbo is a much MUCH better designed system.

For that matter, the differences in a blow/draw through system are great when talking carb'd or EFI. Please, don't confuse the two.

 

[rumptis]

It doesn't technically suck, the pistons create a vacuum and air tries to rush in and fill the void

But a Blow Job does technically suck right?

 

[tissimo]

haha I LOVE turbo dodges!! I had a 88 shelby Z 5spd a few years ago, i never got to make a pass at the track with it, but it was ghetto upgraded and i super gutted it and made it light weight. Im sure i coulda got 13s out of it.

haha yea my dad has a shelby z that were preping for the track next sunday.. putting my old 7m intercooler on it and cranking the boost.. see what it gest.. if its a 14 wed be happy, lol..