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Well started to turbo the c5 yesterday and cut the middle compartment in the back out welded some dom between the rails and made a hanger off of that to mount the turbo. Its off to the exhaust shop this week to basically have a single exhaust from the manifolds back and then the charge pipe in place of the old exhaust.
I do have a few questions before I have the exhaust shop order some parts. Here is the list I got so far. Stock motor gt45 turbo spraying washer fluid.
Is the stock exhaust looks like 2 1/2 to me big enough to flow 600 rwhp? Remember it will be a single pipe from the manifolds.
What is a good size for the charge pipe? 2"? 3" and what are the down sides to going bigger or smaller?
Anything I need to know before we delete the cats? I plan on unbolting the turbo once exhaust work is done and drive the car to the dyno. Tow company wants $500 to take it when I can just drive it up there.
What do I need to do with the maf sensor? Is this completely removed if I install a 2bar or 3 bar map? And what option is best?
60 lb or 80 lb injectors for my hp goal?
And what is the cheapest and best solution for the fuel system? I was thinking bosch 044 and use the stocker as a pusher?
Do I need a rising rate regulator 1:1 with this setup?
Any and all help is appreciated!!! I will be starting a build thread that covers all of this with pics of the work.
From what I'm using on my build this is what ill suggest.
3" both exhaust and charge pipe.
You can use a MAF if you want. I'm choosing not to. Ill be running a 3 Bar MAP. With your goal of 600 rwhp a 2 bar should get you there. This would be something to discuss with your tuner. He/she may have their own preferences here.
Get the lowest one that will make your goal power. You don't want to have to deal with a wider range if you don't have to.
60LB will get you there. However, 80's aren't much more and will give you a lot of room to grow.
At 600 you could use a aeromotive/walbro 340lph and a rewire or possibly a Racetronix pump plus BAP. You'll get a little extra fuel from your methanol kit.
I wouldn't mess with an external pump if i didn't absolutely have to.
If you DO want to go that route UPP and A&A among others make kits.
Get a rising rate regulator from Aeromotive or Fuelab.
From what I'm using on my build this is what ill suggest.
3" both exhaust and charge pipe.
You can use a MAF if you want. I'm choosing not to. Ill be running a 3 Bar MAP. With your goal of 600 rwhp a 2 bar should get you there. This would be something to discuss with your tuner. He/she may have their own preferences here.
Get the lowest one that will make your goal power. You don't want to have to deal with a wider range if you don't have to.
60LB will get you there. However, 80's aren't much more and will give you a lot of room to grow.
At 600 you could use a aeromotive/walbro 340lph and a rewire or possibly a Racetronix pump plus BAP. You'll get a little extra fuel from your methanol kit.
I wouldn't mess with an external pump if i didn't absolutely have to.
If you DO want to go that route UPP and A&A among others make kits.
Get a rising rate regulator from Aeromotive or Fuelab.
Thanks for the help!! I am going to give speedinc a call in the morning and see what they want as for the map sensor. They sell a 3 bar for $63.00 but il see what he wants to do. Also do u have a build thread on here?
From what I'm using on my build this is what ill suggest.
3" both exhaust and charge pipe.
You can use a MAF if you want. I'm choosing not to. Ill be running a 3 Bar MAP. With your goal of 600 rwhp a 2 bar should get you there. This would be something to discuss with your tuner. He/she may have their own preferences here.
Get the lowest one that will make your goal power. You don't want to have to deal with a wider range if you don't have to.
60LB will get you there. However, 80's aren't much more and will give you a lot of room to grow.
At 600 you could use a aeromotive/walbro 340lph and a rewire or possibly a Racetronix pump plus BAP. You'll get a little extra fuel from your methanol kit.
I wouldn't mess with an external pump if i didn't absolutely have to.
If you DO want to go that route UPP and A&A among others make kits.
Get a rising rate regulator from Aeromotive or Fuelab.
Good advice there.
Smaller charge pipe = faster spool at the sacrifice of total power. Bigger intercooler also factors into that. 3" is the most popular size (including on my car) for the ~600hp range.
2 bar speed density is the way to go. It'll get you to 15 psi, and realistically you can run 17 or 18 on it. You'll hit 600hp before you hit 15 psi. 3 bar will give the PCM less resolution and slightly worse street manners. Not sure what year your C5 is, but most years have the intake temp sensor built into the MAF. You'll need to get a stand alone IAT, put a bung on the charge pipe for it, and separate out the 2 wires from the harness for it.
Car is a 1997 A4
turbo I have I am thinking will be the downer to this build its an ebay gt45 thinking of upgrading though. Here is a parts list I got so far with some prices to give me an idea of how much this is all going to cost me.
exhaust shop $400 this is to do the charge pipe for me as well out of stainless.
rising rate regulator $125 http://www.summitracing.com/parts/aei-13129
aeromotive in tank fp $153
fuel rail adaptors 6an $25 for 2
oil feed and return lines $100 ebay
80lb injectors $280 ebay
All the turbo hard parts like bov wastegate boost controller I already have.
got tons of fuel line and fittng laying around.
And yes I know there is a ton of smaller stuff I need fittings clamps etc but to be honest I have built 2 carbed turbo cars now and 2 turbo drag bikes. So I should have most the stuff needed laying around in some boxes.
Could u guys explain the IAT a little more? From what I get out of that I cut 2 wires on the maf and hook to a new IAT sensor and that's it? Thanks for the help guys I am sure there will be some more small things that come up o this build. Got the water meth kit mounted up last night so I am going to wire all that up today etc. Il post pics and build cost as I go.
97 should have a separate MAF and IAT sensor. Google tells me '01 was where they changed to a larger integrated MAF.
97 is good for the fuel system, it means your pressure regulator is on the fuel rail. 99+ C5s have the regulator back near the fuel tank... takes more effort to up the fuel flow on the 99+ C5s. A 340 drop in pump + boost referenced regulator + 80lb injectors should get you pretty far. The stock fuel lines and rails shouldn't be a restriction until you're north of 800 horsepower. I'm sure there are some good threads on fuel system modifications on 97-98 C5s with the return fuel system. I'm not directly knowledgeable on what the popular easy methods are for getting lots of fuel out of them.
Last edited by PhysicsDude55; 02-15-2015 at 10:40 AM.
I did my rear mount build in all 3in. If I had it to do again, I would have done it in 2 1/2 all around. The spool was decent but not great. I redid the charge tube in 2 1/2 and it helped spool time. I had a H/C/I with a stock short block. Car made 420rwhp with a hp cam prior to the turbo build.
What turbo were you running? I think running both 2.5" manifold outlets to a y with a 3" outlet and dropping back down to 2.5" closer to the back would work well also. On the cold side run 2.5" up to the front cradle area and then convert to 3". You can use a lot of the stock exhaust piping this way also if you are cheap like me haha. I've seen 3" intake/exhaust piping support a lot of power on these rear mount corvettes so if you are good with say 800whp running the above size might just be the ticket.
Danzglass's build shows great spool due to the turbo sizing and pretty much zero backpressure on the backside of the turbine wheel. I think the 7175 with a .81 housing he used is about perfect for a 5.7L vette if you are good with 700-800whp. I might try one out on a friends car but the turbine exhaust will split back to dual GHL's and have the normal GHL tips, etc. This might hurt output some, but look a little more standard.
Thanks for all the info guys!!
So far this is what I got out of it all
valve springs $100-? depending what I buy
180lb injectors ebay $280
340lph pump in tank Aeromotive $160
rising 1:1 regulator $70-$170
found some an adaptors that just snap on to the existing fuel rail cheap!! $25 for 2 6an ebay so $550-$650 there
that should take care of the fuel system. besides some fitting's and lines I already have laying around.
I am just going to order a new turbo so $500-$700 is in the budget
Map sensor Found a bunch ranging from $40-$100 still waiting to hear back from the tuner on that.
I have a nice water meth kit that is controllable off boost reference etc
Just not sure what to run in it? water? washer fluid? don't want to have to mix or order anything so has to be readily available.
Max boost with this set up? Always hear I can run more boost with w/m combo.
There are guys on ls1 tech making insane hp on stock motors with turbo so its hard to tell what spring I should put in before I take it to the dyno.
My goal is for it to make 500 wrhp minimum but if I can go more towards or past the 600 mark would be gr8 im just a little nervous as I really don't know the limits of this motor. Has 90k and runs like new!
I am really considering just running the stock exhaust and see where that gets me. I know il get bored next winter and change it to see how much difference it would make. All the tuner could tell me was sts kits he has done see 550whp at7-8lbs and up to 650 around 10-14 lbs on a dynojet
Last edited by turbocvette; 02-16-2015 at 02:38 PM.
I see you were an auto also so you probably didn't lock the converter on the dyno did you? Did you ever take it to the drag strip?
It was dynoed unlocked. Due to it creepn thru the brakes I couldn't get any boost on the brake. It went a dismal 2.05 sixty foot but it ended up going 127 mph thru the 1/4 with an embarrassing 11.50 ET. My only consolation is that if leaned over about 200 ft short of the 1/4 and ended up having 2 hurt Pistons.
02-14-2015, 07:42 PM
diy rear mount turbo have a few questions?
