Carb Turboing
 

Hey
Im planning to turbo my 1985 Mazda 626 so heres what Im thinking

1. Carbed - Bah! I need to do a blow-thru setup. I know I need a new fuel pump but is a fuel pressure regulator neccessary? Plus, to connect the intake piping, is there an adapter of some sort I could buy?

2. Can I connect the manifold, turbo and downpipe plus all the oil lines and drive it like that until I can upgrade the fuel and get the intake piping or will it be incredibly loud?

3. IHI RHB5 - good for a 2 litre engine that goes up to 6000?

I only want to run 6-8 psi on this

Re:Carb Turboing
 

Some basics on carb-Forced induction:

There are a few tricky things to watch out for. With a carb setup, you need to keep the fuel pressure at least 2-3 psi above what boost setting your running. This is something that the FI guys dont neccisarily have to be so careful with, as injectors already fire at a high rate of pressure. If you dont keep your fuel higher than the boost, the boost will actually force the fuel out of the bowls. this can be controlled with a boost controlled fuel pressure regulator, such as this one:http://www.fluidcontrol.net/pages/regulators3.html

As for connceting the charge pipe..Im pretty sure its gonna be a home made job!

As for installing the turbo with out the charge pipe, why? Just wait until you have all the componants you need to do it, that way you wont be putting any more wear on the turbo.

The IHI RHB5 come in a wide range of A/R and impeller size, just like garrets. Some might be well suited and some others might not.

Hope that helps!

Re:Carb Turboing
 

Oh yes, and what fuel pump would you recommend? Im only going to be boosting as high as 9psi so Ive been trying to find a nice 11psi pump, but cant ??? any suggestions?

Re:Carb Turboing
 

Do not rely on the fuel pump to control pressure. besides, if you run a high fuel pressure, you may and probably will overpower your carb floats and gaskets, and cause some serious leaks in the carb.

Most aftermarket electric pumps(Summit,Jegs) run around 20 psi, again, your going to need some way to regulate fuel pressure to the carbs.

Boosting a carb setup isnt going to be easy.

Aaron

Re:Carb Turboing
 

Good luck trying to find solid floats for that carb.. you're also going to have to rejet it or install fuel injectors to compensate for all the extra air.

Boosting a sbc is one thing (parts, availability) but I dunno about your mazda, maybe you need to look into other project options. Just a suggestion.

I know people get attached to cars, but this one is going outside the realm of practicality.

Re:Carb Turboing
 

Ive heard of people filling the floats with foam to stop them crushing - I was thinking of doing that
The 1985 Telstar TX5 - [same FE engine as mazda] came in a carbed/turbo model - thats the engine that will provide most of the donor parts, so I kinda assumed that most of it would be OK - if not I could just steal the carb of that

Re:Carb Turboing
 

Just EFI the biatch!

Re:Carb Turboing
 

agreed.. carb setups are a pain in the ass.. although you may get it running.. it will never run like a EFI setup..you cant tune the carb setup like u can a EFI setup but to each their own... good luck with w.e u deside

Re:Carb Turboing
 

I was thinking of that...
Im on a budget though...about $500AU
So would that be enough?
Any links on how to convert or anything?