Planning An LS1 Build

[Ginger Beer]

Have you thought about a single turbo?

A "correctly" sized spooly boy will give good response

Sometimes I wish I went a single turbo instead of the Harrop HTV2300 that I went with

Whilst my PD blower is good from basically idle, there was alot of hidden costs and mucking around to get it working like I wanted (read: interchiller, thermal spacers, firewall modifications)

With a turbo, tuning boost per gear is a big advantage that is simple with a good ECU

The trick, whilst not too hard, is correctly sizing a turbo, not only for response but also your power goal

The turbo technology nowadays is awesome for both power and response

 

[Pollushon]

Wow! Now that's interesting. I expect to hear back from Tim today. What you've raised, has yet to come up in conversation. But I'll be sure to bring it up now.

If you've a moment, care to give me a brief on what you mean and why ("the LS will eat it up..." and "they don't have the velocity for a built LS.")? Thanks muchly...

It's going to come down to what you do or plan to do. The Raptor is a great blower but it's a baby as far as volume goes. If you leave the bottom end stock it's probably usable but you might be disappointed for the bucks. Higgins heads and a longer duration means you can kram more air per bang, which means less resistance and less pounds. If you stroke and forge then it's not going to keep up and you can only spin them so fast. See what Tim says but if I were venturing down your path I'd want a 2.0L pd (minimum) or turbo kit to keep up.

I have an M122 PD on a fruity LS1 stroker built for 1k hp and it can barely push 8 pounds through it. Still big power, just a far cry from its potential

 

[elliottecarter]

Thanks for that.

Yes, initially I thought turbo. Looked into it along with everything else. And here we are.
But now … I’m curious again.

Sounds like you paid for your Harrop in more ways than one.
Shame.

Interesting about tuning with a turbo “per gear.”


Can’t help but notice your emphasis on choosing correctly. In what direction do you think I ought go to explore this further as a potential option; and, if so, the ‘trick’ to correct sizing?

Thanks for sparking this idea again.

 

[Ginger Beer]

Thanks for that.

Yes, initially I thought turbo. Looked into it along with everything else. And here we are.
But now … I’m curious again.

Sounds like you paid for your Harrop in more ways than one.
Shame.

Interesting about tuning with a turbo “per gear.”


Can’t help but notice your emphasis on choosing correctly. In what direction do you think I ought go to explore this further as a potential option; and, if so, the ‘trick’ to correct sizing?

Thanks for sparking this idea again.

I don't know if this has turbo efficiency maps for you cubes

But, over in the JDM forums, like Skylines Australia, there is a heap of info on all the new turbos, and real world results on how they perform from stock to stroked 2.0ltrs up to 3.2 ltr RB engines

My best input would be to ask local tuning shops about your wants and needs, and whilst a compressor map will tell you most of what your after, nothing beats real world testing and tuning

Boost by gear/rpm/mph is pretty simple. In layman's terms: you can set boost limits so the boost/power will only come on where you want it, like, if you are losing traction in a gear, you can lower the boost down a bit until it reaches a certain RPM/MPH, so you launch in first at 4psi, 2nd gives you 8 psi ramping up to 15psi, 3rd gives 15 psi and ramps up to 25psi, 4th is all in

Boost by gear, RPM and MPH help with traction as well as mechanical sympathy/engine protection on rods and bearings, high boost and low engine speed/RPM puts alot of load on rods and bearings, even when they are built using premium parts

Most people I know with high HP boosted cars use it now for the reasons I stated above

The other benefit with a turbo and boost by gear/RPM/MPH control is you just page up for power, or down for traction

You do need a good ECU though, Haltech 2500 have it all if you want to do some research on what they can offer

 

[07GTS]

Thanks for the breakdown on the stall. Looks like it’s worth spending the time learning more about E85 cos that’s a helluva difference for a boosted LS.

When you’re talking about compression, what are we doing to adjust it/maintain it? I guess I’m asking what considerations factor in to compression.

Really appreciating your feedback. So helpful.

static compression is set by the piston, cylinder/chamber volume, but dynamic compression is set by intake closing event, the static compression is calculated from bottom dead center thru the stroke up to top dead center, but the intake valve is open for some of that intake stroke so compression dosnt start until its sealed and that is dynamic compression as it is always changing based on the engines demand, compression should be set to actual peak boost, fuel type, camshaft

 

[elliottecarter]

I don't know if this has turbo efficiency maps for you cubes

But, over in the JDM forums, like Skylines Australia, there is a heap of info on all the new turbos, and real world results on how they perform from stock to stroked 2.0ltrs up to 3.2 ltr RB engines

My best input would be to ask local tuning shops about your wants and needs, and whilst a compressor map will tell you most of what your after, nothing beats real world testing and tuning

Boost by gear/rpm/mph is pretty simple. In layman's terms: you can set boost limits so the boost/power will only come on where you want it, like, if you are losing traction in a gear, you can lower the boost down a bit until it reaches a certain RPM/MPH, so you launch in first at 4psi, 2nd gives you 8 psi ramping up to 15psi, 3rd gives 15 psi and ramps up to 25psi, 4th is all in

Boost by gear, RPM and MPH help with traction as well as mechanical sympathy/engine protection on rods and bearings, high boost and low engine speed/RPM puts alot of load on rods and bearings, even when they are built using premium parts

Most people I know with high HP boosted cars use it now for the reasons I stated above

The other benefit with a turbo and boost by gear/RPM/MPH control is you just page up for power, or down for traction

You do need a good ECU though, Haltech 2500 have it all if you want to do some research on what they can offer

Thanks for that. I’ll be revisiting turbos now I’m a bit better armed. This “boost by gear/RPM/MPH” control really has my attention.

To-date, feedback on the PCM (when asking about upgrading) has been that it’s okay. But I do understand what you’re saying, so yes I have looked at Haltech. Amazing. And expensive. So, for now, it’s an expense potentially for the future.

 

[Ginger Beer]

Thanks for that. I’ll be revisiting turbos now I’m a bit better armed. This “boost by gear/RPM/MPH” control really has my attention.

To-date, feedback on the PCM (when asking about upgrading) has been that it’s okay. But I do understand what you’re saying, so yes I have looked at Haltech. Amazing. And expensive. So, for now, it’s an expense potentially for the future.

You can also pull some timing from the midrange, well, if the stock ECU will let you

I really, really want a Haltech ECU, I want the option to run 2 maps, one for the street on street tyres, and one for the strip on drag radials

 

[elliottecarter]

static compression is set by the piston, cylinder/chamber volume, but dynamic compression is set by intake closing event, the static compression is calculated from bottom dead center thru the stroke up to top dead center, but the intake valve is open for some of that intake stroke so compression dosnt start until its sealed and that is dynamic compression as it is always changing based on the engines demand, compression should be set to actual peak boost, fuel type, camshaft

That’s handy to know. Thanks

 

[elliottecarter]

You can also pull some timing from the midrange, well, if the stock ECU will let you

I really, really want a Haltech ECU, I want the option to run 2 maps, one for the street on street tyres, and one for the strip on drag radials

Yeah, I hear you: That ECU is a bit hard to ignore.

 

[07GTS]

You can also pull some timing from the midrange, well, if the stock ECU will let you

I really, really want a Haltech ECU, I want the option to run 2 maps, one for the street on street tyres, and one for the strip on drag radials

u can have thousands of tune files for the stock ecu and just keep one for the track and flash it in, then flash back in a normal driving tune when u finish, u could even have one for track on a 25 deg day with a bit of adjustment to timing for the track and another for say a 10 deg day and so forth, same with trans if u want to dial in the shifting better just for the track