CB turbo

[Rice_boy]

Hi, i have a CB lancer GL 4g15 5 speed and im putting a turbo on the standard motor to giver her a little more up and go and was pointed to this forum by a gentleman who owns a purple cc gsr with a 4g63 in it.

So far ive got most stuff covered except for the exhaust sizing the turbo i have is a t3 off a saab 9000 and it had 2 1/4 exhaust the whole way through but i can't decide whether to go with 2 1/4 or 2 1/2 pipe the whole way through. I want fast spool up of the turbo but want the low end tourque when it is off boost.

 

[iluszn]

Hrmmm.. I would be looking at fitting a TD04 turbo if you want torque, one off a CC GSR. T3, what are the specs of these turbos.. it might be overkill and you might not have it boosting till 4500rpm.. But i would go the 2.5" exhaust on it but then again... If you want to go turbo, then do it right, save your penies for a 4G61 or 4g63.

Just my opinion

 

[xjokux]

I would save up as iluszn said. Trust me its worth every penny coming from a 4g61 to 4g63t just recently

 

[rob323]

If it's off a 9000 as you say, they did spool very early (around 2500 rpm), but bare in mind, that was on a 2.3 litre motor. If it's off a Saab 900 then it's a little smaller as it's to suit a 2 litre motor and they spooled a little later.

Don't worry about exhaust size, it will make bugger all difference for the low levels of boost you will be able to run on a standard motor (are the wastegates on the saab turbos able to run real low boost?). The turbo will provide all the back pressure you need so you don't lose low down torque.

 

[Rice_boy]

the turbos off the 2 litre and i dont know the specs off hand and ive got all the parts already like the turbo, carby etc its just something a bit different to grasp the principles of turbo charging and after that if the motor dies i'll put in a 4g63t or something.

 

[cblancergsr]

the question is not if the motor dies its when it dies

i dont think anyone would waste money on a 4g15 carby if they are going too upgrade soon

id definetly recommend 4g63t due too being a greater cubic displacement motor soo it return more boost and capable of producing more power hands down

i thought saab 900 had a k26 turbo

 

[GrantDixon]

Ive just done a 4g15 Carby to 4g63t conversion in my cb lancer and Its by far the best thing Ive done!

Just save money and put it towards and do the conversion and dont worry about the carby.

 

[cblancergsr]

yer its definetly a waist of time and money and theres alot of people how have done these conversions before im thinking of doing the same thing putting a 4g63t in my cb lancer gsr when i can save the money too get a half cut
2nd year apprentice mechanic wages are shit

 

[Jazz9]

Hmm,

I just put a 4g61t into my daily driver - soooo much wheel spin !

I reckon that a 1.5ltr carby turbo would be ok. If you can do it for $500 or so ... why not?

I think that you could run 6psi or so on the stock motor - how are you going to setup the carby?


Glen

 

[cblancergsr]

my N/A 4g61 has enough wheel spin as it is

but yer it would be a unique piece of work a 4g15 turbo cb lancer make people turn there heads

 

[GSR70Y]

my N/A 4g61 has enough wheel spin as it is

sorry I just laughed when i saw this.

If you think a 1.6 n/a cb has too much wheelspin for you, I think you'd shit yourself if i took you for a spin in my car.. :lol:

 

[Rice_boy]

the carby is blow through with the powervalve to work on boost. It is mechanical secondary and will be running a bosh external efi fuel pump rom a vk with a malpassi 1:1 carb regulator set to about 6-7 psi base pressure and rise 1 psi for everypsi of boost.

im going to get the tunners to play with the jets, emulsion tubes and air correction valves so she'll hopefully follow the engine requirements when boost kicks in without hesitation. or just a bit when she starts to boost.

 

[rob323]

Efi pumps are normally suited to high pressure, low volume. They don't normally like being used as a low pressure, high volume pump, that's what facet and holley etc pumps are for.

 

[mrcyborg]

the pump will still flow the volume alright, but they may not like the pressure you hold it down to, down low.

 

[rob323]

But if an efi fuel pump can flow say 100 litres per hour at 40psi of pressure, imagine how much it will want to flow at only 7 psi. Assuming the fuel return line is big enough and the FPR can flow enough (and doesn't cause a restriction which will make the fuel pressure at the rail go up no matter how low you set the FPR), all you will be doing is cycling most of the fuel from the tank to the rail and back to the tank again, which everyone seems to think is not a good idea as it keeps heating the fuel up.

By all means, let the OP try it, but if you have too much fuel pressure, not matter what you set the FPR too, and too much fuel going back down the return line, then I would look at using a different pump, one designed for carbies, not efi.

 

[cblancergsr]

the only thing is the fuel pumps that are designed for carby engines are mechanical not electronic soo they run of an eccentric lobe on the camshaft

unless you are talking about an electric universal fuel pump for carby

 

[rob323]

Holley pumps and Facet pumps are all electric. Rotaries all use electric pumps.

 

[Rice_boy]

The problem is it will be at 7 psi of boost so i need at lest 14 psi of fuel pressure because i will be running 7 pounds of boost plus 7 pound base fuel pressure when of boost