Turbo 4AF, domestic cars have been doing it for years - Toyota Nation Forum : Toyota Car and Truck Forums

TJsedan · 03-31-2011, 05:19 PM

I just wanna know has any one actually went all the way through with turboing the 4AF motor with out going to EFI. I have done my research quit extensively and i cant find any one person who has done it.

I know its possible from reading "muscle car" forums with possible blow through or draw through set up. im looking to turbo my 4af because im pretty sure i can get most of the stuff pretty cheap from junkyards and ebay this costing muchless than an engine swap. im no mechanic so i dont have a strong background in working with carbs or turbo systems but im an engineering student and an ad-vied tinkerer.

I have a factory manual and im sure for a blow through system my parts would be:

Turbo (on stock internals max 9 psi)
Turbo manifold
fuel pump (fuel pressure must be 3.5 above boost)
fuel pressure regulator
pressure box
waste gate
oil return line for oil pan
intercooler
piping and tubing
misc. brackets

if anyone can help me out that would be great!

eage8 · 03-31-2011, 05:29 PM

flashmn did it before converting to EFI....

turbo carbs just aren't very fun.

I would get a weber carb or something first so you can actually tune it.

also, the stock carb runs at 6 psi and the fuel pump is cam driven and mounted to the head...

Flashmn · 03-31-2011, 06:14 PM

Quote:

flashmn did it before converting to EFI....

I never did have a carb turbo. Converted at the same time as I did the turbo.

...but doing a carb turbo isnt an impossibility with a 4A-F.

TJsedan · 03-31-2011, 06:43 PM

why isnt a turbo carb fun? tuning?

well i would install a weber carb kit after i get the system to work right. i dont want to waste money if the stock carb is going to run fine.

stock carb psi? wouldn't and electric fuel pump work better with the turbo?

i wish i could see flashmn's car but his/your site is down

Flashmn · 03-31-2011, 07:50 PM

Yeah, I dont have that site anymore.

Easiest way to do it is to make a pressure box covering the carb (check out vortech kits how it would look like), a fuel pressure regulator that has boost reference, an electric pump that supplies 6psi base pressure + boost pressure. So if you're hitting 6psi of boost, it would be 6+6 = 12psi total.

Why isnt a turbo carb fun? I never said its not fun, I said its not impossible to do.

eage8 · 03-31-2011, 08:13 PM

I said it was no fun because tuning carbs sucks

will the stock carb take 12 psi of fuel pressure? I would assume bad things would happen to the floats...

here is an interesting site I just found on google... :-P http://www.dune-buggy.com/turbo/carbureted.htm

Flashmn · 04-01-2011, 05:47 AM

I would assume it would work with the stock floats.

SuperRA · 04-01-2011, 03:07 PM

I think the stock floats are made of a buoyant polymeric material, not hollow metal.

Flashmn · 04-02-2011, 05:42 AM

AFAIK they're hollow plastic.

SuperRA · 04-02-2011, 02:09 PM

Ok, well, I meant that I didn't think they were hollow at all, but I'd have to break one apart to be sure.

Flashmn · 04-02-2011, 02:57 PM

Just saying because there are floats that arent hollow

canadianae92 · 04-03-2011, 10:31 PM

Yea its doable, dont try with the stock carb, as for webers lots of rx7 guys turbo with a dcoe, they fill their floats with something cant remember what, some sort of foam. Anyway the info is out there. Besides that it'll be a bitch to tune. The muscle car guys actually have carbs ment for blow through setups, there is actually a set of dellorto side drafts i think that were made for a blow through setup on a alfa romero or w/e.

There is a fair bit of info on turboing cv carbs on r1 bikes, theres a guy with a ae86 with a full carbon kevlar shell that ran cv carbs on a 4age turbo, said it was easy to set up. However bike carbs are sort of a dark road, not all that much info on them. 240z and 280z guys have some carb turbo info out there. Btw the info I'm mentioning is all for blow through setups, you don't want draw through.

Flashmn · 04-05-2011, 06:48 AM

Its the brass floats in the DCOE that need to be filled with a two component foam. The brass floats can take up to about 0.5bar without distorting.

Both weber dcoe's and dellorto dhla's have turbo versions that have the pressurization for the float bowls done easily, but you can do it with the regular ones too, you just have to make the kit yourself. I almost went that route, now hindsight 20/20, maybe I should of, would of been way easier to deal with some things.

eage8 · 04-05-2011, 09:38 AM

Quote:

Originally Posted by Flashmn

Its the brass floats in the DCOE that need to be filled with a two component foam. The brass floats can take up to about 0.5bar without distorting.

Both weber dcoe's and dellorto dhla's have turbo versions that have the pressurization for the float bowls done easily, but you can do it with the regular ones too, you just have to make the kit yourself. I almost went that route, now hindsight 20/20, maybe I should of, would of been way easier to deal with some things.

Tell me 1 thing that's easier to deal with with carbs...

carbs suck, I'll never go back

I need to convert my bike to EFI...

canadianae92 · 04-05-2011, 12:28 PM

I though about goin turbo with my dcoes but idk, I'm using high comp pistons, temp setup either way but I think going turbo would over complicate things. Still finicky as na but I don't mind carbs personally and webers are supposed to be the pickiest of the bunch.