rop3

Running all stock externals on engine, except larger intercooler, new cam headwork and rebuilt engine.

For street use what turbo would give best spool up power combo least lag?

JDS968

You can get as many recommendations as you want...but I'd suggest you run the calculations based on what your own goals are for your own car, then go read the compressor maps for different turbos until you find the smallest one that can handle the boost you want to run.

brrgrr

JDS968 hit the nail on the head - there are probably 10 different turbo's that "fit" - the key is matching the turbo to your HP goal. The smaller size will give you quicker spool up and a better "street" solution.

Ski

isn't time you change you avatar and dump the red thing?

fast951

It will help if you refine your requirements and goals:
- What sort of HP are you aiming for? Would you want more soon or you will be satisfied?
- What do you consider good spoolup? 1bar boost by 3000RPM or 4000RPM?
- What other supporting mods do you plan on getting? A chip, a MAF, a standalone, injectors?
- What would you be using for boost control? Stock WG or a dual port WG?
- Do you need to keep stock appearance? Keep stock air box and J-boot?
- Do you want a turbo that bolts directly to your exhaust? Or are you willing to make exhaust mods?

As you can see, there is no one size fits all turbo. Once you determine your requirements, it will be easier to identify the turbo that will match most of them and you will rule out the turbos that will fall outside of your search criteria.

docwyte

What John said. Once you figure out the answers to the questions, John and others here and steer you in a good direction.

brrgrr

Avatar changed per Ski's request.

Back to the turbo discussion -

The link below is a great tool to get you in the right ballpark.... it has the compressor maps and will plot out your values depending on the inputs you select.

http://www.squirrelpf.com/turbocalc/

Richgreenster

Cool link but I dont quite get it.

Target Power: hp
Engine Size:
Target A/F: :1 (I thought that 12:1 was target for every car)
BSFC: (What are you guys putting for the 951?)
Max I/C Loss: psi (How do you know this value?)
Pressure Ref: psi (Do you just input the altitude that you are at?)

RPM Points Vol. Efficiency Intake Temp
Engine Redline: rpms -> % -> deg F
Peak Power at: rpms -> % -> deg F
Max Boost at: rpms -> % -> deg F
Min Boost at: rpms -> % -> deg F
(I dont quite get Min Boost.. Is this where you have some boost..above 0 psi...?)

Then when the chart is loaded for each turbo is the red plot line better to go straight up the center or should it be closer to the surge line?

brrgrr

I left most of the defaults alone, I put 2500 in for "min boost", 3000 for max boost, and a target HP of 375. Power peak at 5900 rpm, redline at 6300.

you want the red dots to be in the highest efficiency part of the map - you don't want any of the dots to be "left" of the surge line.

For a target HP of 375 - the GT2871R-1 looks like a nice fit, along with the TO4E Super 50.....

Rogue_Ant

A GT2871 would be an awesome street turbo! But some mods are needed to bolt-it on for the 951.


-Rogue

gt37vgt

Awesome on an all standard engine
well you can get them in a KKK hotside ... the oil drain looks the same (famous last words)
http://www.034motorsport.com/product...ducts_id=13762
just need to sort out the compressor inlet and oil and water .
I think an an engine with the head cam and inter-cooler upgrade deserves the step up to Gt30 of even 35

Richgreenster

Some one needs to come up with all the 951 turbo options and turbo maps in a cool site like this one. Do any of the turners post the turbo maps to their turbos? I remember when I went looking for my turbo the tuners would not give you very much info of what turbo you were buying. I bought mine kind of in the dark and only trusted what they said it would do. With that said What would a T04B-50 map look like?

Rogue_Ant

At 50trim would be a great fit as well - just older tech then the new GT stuff.
Good luck getting much turbo spec info out of the tuners... LR is about as forthcoming as they get.

gt37vgt

thats why i wouldn't touch most 951 tuner turbos

Richgreenster

I have the TO4B not the E. I think that the intake is 2.75" on mine and the E is 3" but I could be wrong. I have looked for the map on mine but could not find it anywhere.
p.s. I love the pic of your engine in your avitar.