Help me understand HP potential of S vs TT

TopgunZ

I know im probably going to get my balls racked here but I am just confused.

I drive a 350Z with the Powerlab kit with a single GT3584R. It is capable of putting down 550whp. And its a single smaller turbo. And there is room for more.

I am looking at selling my car and purchasing a 370 in the near future and am excited yet I want to make sure I get the right kit on there the first time.

I inquired into the GTM stage 2 twin turbo kit. The sales rep shot me back an email stating that at 550whp I would be maxing that kit out, the GT28's with the .84.

So I am just confused as to how you can have a single turbo, that isnt all THAT much smaller than a GT28, making the same power #'s as TWO turbos of a slightly smaller size, on larger engine. Has it got all to do with the fact that they really do just drop off in efficiency at such a lower psi?

I would like for there to be room in my system for growth and I also wouldnt want to be pushing my turbo's super hard all the time.

DEpointfive0

Search feature, we just had a thread like this 2 weeks ago

homeryansta

Im no expert, but isn't the purpose of twin turbo is to have a smaller turbo spool quickly for low end and a bigger one for high end?

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SS_Firehawk

550whp is basically the accepted breaking point, so if the motor isn't built, we stay below that. The GTM TT kits have plenty of room to grow. Mr Squeeze is putting around 650whp with his. The supercharger kits from them have been shown to break 500whp and can hit the 550whp mark. So it's more of a pick your poison. Boosted performance offers a mid mount twin scroll system, S&R offer a single top mount they install (transport to them), STS offers a rear mount, and Stillen offers their SC system, but if you are looking to hit 550whp or higher, it won't get there. GTM also has a twin supercharger system available (kind of) that can push big numbers as well, but turbo's would be a cheaper option.

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SS_Firehawk

Lol DE, you are my daily source of entertainment

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Mitco39

Ibtl!

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G37sHKS

Im sorry but the "sale rep" seems like he doesn't know what hes doing..

I made 500 WHP with GTM stage 1 with just 8.8PSI stock engine/transmission, Now that being said, im sure you can achieve 600 WHP mark with stage one with higher boost...

If you are going for big turbos then might as well go for Single turbo because lag is going to be there in either kit anyways...

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TopgunZ

I read that thread on Single vs TT. I am aware of benefits of setups. I am aware of the offered kits. But, his response is what threw me for a loop.

Here it is.......

"All of my statements are assuming a quality tune in which chances of detonation would be little to none. ~550rwhp is not a limitation for even 91 octane fuel on a VQ37, however it seems as though you have already made your decision. I would recommend going with turbos larger than stage 2s if you are concerned with detonation, they would be operating near there limit at around 540rwhp which drastically increases AITs. Actually we do not have cooling issues with our VQ37TTs, even being in a much warmer climate, so I could not relate to that statement."

WHen he states the stage 2 with the larger .84 ar vs .61 would be operating near their limits at 540rwhp is what concerned me. My slightly larger GT35 can hit that. See what im getting at here?

Mike@GTM

What sales rep did you talk to?

The GT2860RS turbos in our Stage 2 kit do not max out at 550whp. You can push them to 600+ no problem if you have the motor build to support the power.

TopgunZ

I guess I should not have said rep. It was a rep for a distributor of your kits. A very well known distributor I might add.

Would you like me to PM you this information?

But yeah thats what I thought. When he told me at 540 you will be maxing them out I got confused.

OK. I didnt want to get into it but I actually just inquired about cost of a tuner kit. I told him I had ID1000's and an Aeromotive 340lph and return system and wanted to run E85. So I was wondering if they offered tuner kits. He told me they do but then told me it would be stupid to run the E if i didnt have a built engine.

Chuck33079

A GT35 is not "slightly" larger than a GT28. It is a much larger turbo.

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2011 MB Touring-Sport-6sp-Nav/GTM TT/FI TT TDX/JTran/Kosmic/Eibach/Hotchkis/SPC/CSF/RPS/SoThatsWhereAllMyMoneyWent

TopgunZ

Well..Garrett offers 20 diffent sizes of turbos..many more different combinations, but overall sizes. There are only 2 turbos in-between the GT28 to the GT35 so i would say that it is slightly larger, for my question at hand.

Chuck33079

Looking at the compressor maps of the two, the GT28 is around a 35 lb/min turbo. Maybe 40 if you run it all the way out to the very edge of the compressor map. At that same pressure ratio, the GT35 is moving almost 70 lb/min of air. At lower pressure ratios, they look similar, but I don't know why you would buy a GT35 and not run higher boost.

Did you ever own a Supra? Those are the only guys who I've heard use the words "small" and "GT35" in the same sentence.

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2011 MB Touring-Sport-6sp-Nav/GTM TT/FI TT TDX/JTran/Kosmic/Eibach/Hotchkis/SPC/CSF/RPS/SoThatsWhereAllMyMoneyWent

Coon-azz

I' don't have all the technical input, but I would consider what kind of performance driving you are looking to do. This is just my 2 cents. I have had both. I've found that the Supercharger is a better option if you plan to do solo racing and/or more stoplight to stoplight (short distance). If you're doing more longer runs, a turbo might be the way to go. It's just my 2 cents. I've seen both do really well at both kinds of driving and new technologies are really helping equal the playing field.

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I don't care how slow you want to drive; I encourage it. JUST GET THE HELL OUT OF THE PASSING LANE YOU TUCK FARD!!!

TopgunZ

Ok well this doesnt have to do with my initial question. But im looking for a no-lag system. I enjoy spirited street driving and stop-light to stop-light fun. But, I will take it to the track and get some 1/4's in and I am looking to get into some track use now also. But 95% of the time it will see city roads.

So for that im looking to put down between 500-540. So I guess the GT28's would be my choice if i have done my math.I would like to upgrade to the GTX's though. Possibly the BP kit. Again, the less lag for me the better.

I was use to a 350z stillen once..lol..