Jump to content
HybridZ

singleturbo carbed 320hp l28, looks easy please look!


hondabait

Recommended Posts

Wouldn't the combination of a high spinning turbo and the quick shutting of the throttle on a draw through setup make a spike in vacum in the intake and a spike in pressure in the manifold. I thought it was these spikes in pressure that destroy turbo's. Wouldn't it still need a BOV or atleast BOV in reverse between the carb and turbo to limit vacum or maybe both? dumb question I know.

Link to comment
Share on other sites

  • Replies 81
  • Created
  • Last Reply

Top Posters In This Topic

Wouldn't the combination of a high spinning turbo and the quick shutting of the throttle on a draw through setup make a spike in vacum in the intake and a spike in pressure in the manifold. I thought it was these spikes in pressure that destroy turbo's. Wouldn't it still need a BOV or atleast BOV in reverse between the carb and turbo to limit vacum or maybe both? dumb question I know.

 

No, there is no build up of pressure to neccessitate a BOV. Like I said in my previous post the only reason for a BOV is to relieve the build up of pressure between the turbo and thottle plate(s). With the turbo after the throttle plates there is no way to stall the turbo by closing the throttle in a draw through set-up.

In a draw through set-up, anything after the throttle plate(s) once closed is in vacuum. Once there is a lack of supply of air (closing the throttle), there is no way for the turbo to create positive pressure.

Link to comment
Share on other sites

Here are the main components of Turbo Tom's system laid out.

 

DSCN1791.jpg

 

The bubble wrapped in the top right holds the meth/water tank that is injected into the intake manifold. I plan to look at progressive injection of the mix in my install.

 

Below the meth/water tank is the intake plenum. It has a water heated section at the bottom to ensure fuel does not puddle on cold days.

 

Choosing an appropriate fuel pump to feed the carb is also required.

 

This kit does not have the "dial-a-boost" option.

 

Hope this helps those thinking about draw thru options.

Link to comment
Share on other sites

I got by my storage unit today and took some pictures of my setup as it was removed from my car.

 

1 and 2) Complete setup as unbolted

3) Water lines from thermostat housing and then to the heater box. Also show vacuum line to brake booster.

4) Head view of manifolds. Also shows waste gate at lower left.

5) The water injection nozzle as it sits under the carb.

 

I used a spray nozzle to mist the water into the fuel air mixture after a friend had a problem with his turbo being scored by a straight stream of water. I also used a 20% alcohol mix in my water.

 

The waste gate uses a 7 pound spring and a dial type boost controller. With this setup I was able to run 10psi on the street and then turn it up to 15psi on the track.

 

I've got a few more pictures if anyone is interest.

IMG_3450_thumb.JPG

IMG_3454_thumb.JPG

IMG_3455_thumb.JPG

IMG_3452_thumb.JPG

IMG_3456_thumb.JPG

Link to comment
Share on other sites

Found this in my picture archive. (The picture is not mine and belongs to Dave Smith). I thought this might give you some ideas about adding a weber to your turbo engine.:idea:

 

im very interested in this setup. so a single side draught is enough to handle a turbo'd 2.8? any ideas on how the carb was setup?

 

plus, is water injection still necessary if boost is only goin to be under 8psi?

 

thanks

Link to comment
Share on other sites

Yes, the carb is a standard Holley 750. We played with the jetting on the Dyno to get the mixture right. I honestly don't remember what jets we ended up with.

 

The setup easily made 300+/- horsepower depending on boost level.

 

The water injection is not typically necessary if you keep the boost to stock (7-8 psi) and use premium fuel. Anything over that definitely requires it to avoid detonation.

Link to comment
Share on other sites

I've honestly thought about it. I'm not sure if I should keep the setup as a cool piece of Z car history or sell it so it could be blasting down the road under someone else's hood.

 

I've got a good bit of money in a new carb, rebuilding the turbo, coating all the manifolds and sourcing the proper water injection valve (one of the last ones Turbo Tom had). I only ran the setup for about 3-4K miles until I bought an EFI turbo setup from a buddy who is building an RB-26.

 

Make me an offer?

Link to comment
Share on other sites

The kit contains three custom castings (intake and exhaust manifolds and the carb plenum). The intake/exhaust manifolds are relatively simple pieces. I suspect the carb plenum would be a different matter since it's dual walled to allow water to circulate around the air/fuel charge. Also keep in mind that the castings all require machining to ensure proper hole alignment and mating surfaces for the turbo and head attachment.

 

If you had access to design software a casting foundry and a machine shop it could be done.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...