Nissan 370Z Forum - GTM Performance Engineering: MHI Twin Turbo Official Release

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I was one of the members who went for a ride on the test car with Sam. The power this new TT kit makes was unbelievable! :eek2:

To be honest, I don't mind having a stockish looking car that can make this kind of hp and tq. :stirthepot:

Sam, I am still waiting for the quote out the door :tup:

Omg I want in. When do you think you will close this? Just ordered a big brake kit and funds are low. After I know that, ill contact you about getting on the list

Quote:

Originally Posted by SAM@GTM (Post 2257037)

Anytime you run a small turbo with internal wastegates, there is a chance of having boost creep if you are not careful with your exhaust system choices. This is not a characteristic of the 16g specifically, it is a concern of anytime you run a small turbine housing. Even in our Garrett based stage 1 kit that comes with the .64 A/R housing, if someone wants to order it, we always ask what type of exhaust they have or what they plan on running so they don't have boost creep issues.

So if you are planning on buying the 16g kit even though we have done a very good job of polishing the wastegate port, I would not suggest running a high flowing 3" exhaust with internal wastegates. If you are planning on running factory exhaust or factory cats, then it is an excellent choice for an extremely responsive setup and you won't need to worry about boost creep. One other thing, is that an automatic puts more load and can exacerbate boost creep on small turbos. The car we tested on did extremely well on the factory exhaust and cats as far as boost control and also did well with test pipes and factory exhaust. But, when we switched to complete open exhaust, we did experience a couple psi increase of boost over our target boost setting.

We are very careful in recommending the right product to our customers so that there are no surprises and challenges after the install. Also, having all three trim options the same price will make this choice easier for the end user since money is not an issue: only desired performance.

We had two different members stop by our facility to check out our 18g test car and both were blown away by how fast and responsive the car was. Hopefully they'll post their experience.

The new manifold design is done and we are waiting on the pre-production pieces to arrive. Once we have them in hand, we will post the nice, shiny pictures. ;)

The blow off valves can be setup for full vent to atmosphere, 50/50 or full recirculation on the MHI kit. Also, I saw that you asked about HKS blow off valves in a different post and we are willing to accommodate special requests like that.

Sam

How much of a factor is boost creep with 2.5" exhausts? Seeing as how that is the norm on most of the aftermarket exhausts for the Z. I'm planning on the Berk CBE for mine.

Where exactly are the 2 intercooler pipes located that have a reduction in them? What is the piping size?

I purchased and just installed the stage II kit and my only regret would be not going with the stage1 kit due to full boost not coming on until around 4500k. And yes I even have their 3' test pipes. Keep that in mind when you order your kit even on the new one... If I had to do it again I would go with the smaller turbo's...

Not sure how much boost your pushing Cosmo, but I generally see the Stage 2's reach 10-12psi at like 3500rpm. It would be a good idea to create a separate thread to see whats up.

Quote:

Originally Posted by Akmcmahon (Post 2257563)

How much of a factor is boost creep with 2.5" exhausts? Seeing as how that is the norm on most of the aftermarket exhausts for the Z. I'm planning on the Berk CBE for mine.

This could be more of a factor if you are running the 16g kit with an automatic transmission and 3" exhaust. If you don't have this combination, you shouldn't have any issues. Besides, our third in house install car will have 16g's with a 2.5" exhaust and we'll have more data to report once the installation and testing is complete.

Sam

Quote:

Originally Posted by BlkNismo (Post 2257696)

Where exactly are the 2 intercooler pipes located that have a reduction in them? What is the piping size?

There is no reduction. We are running 2.5" piping on the entire kit except the MAF piping where it is 3".

Sam

how do I get on the list

Quote:

Originally Posted by qnguyen018 (Post 2259847)

how do I get on the list

Send sam a pm, and he'll get you set up. :tup:

Well just got my quote from the installer on how much to install the new twins, clutch and the exhaust. Only $2700 for everything to be installed. At the same time I'm going to tackle this myself and put that $2700 to good use elsewhere on the car. That quote was also at $90 an hr. He also said about a week to complete everything including the tune.

So I may have to step up my game to match that time frame since I'll be doing on a Sunday and through out the week when I'm off work. Now just need a release date.....already have an oil cooler(34 row) and transmission cooler in route.

Quote:

Originally Posted by qnguyen018 (Post 2259847)

how do I get on the list

Added! Thank you, sir.

Mike what are your guys thought on wrapping everything? I was planning on wrapping it before I do the install. I been reading a lot on wrapping and it seems to help. I know it's not necessary but still would like a second opinion.

I plan on ceramic coating then titanium wrapping everything.

Quote:

Originally Posted by tower74 (Post 2260432)

If by wrapping, you mean thermal wrapping, yes, you can. That said, I wouldn't really do it on this setup.

The way our kit is setup with our exhaust manifolds and heat shields, heat stays in the exhaust before the turbo extremely well and once the exhaust goes through the turbo, then thermal management isn't a significant issue. Sure, you can wrap the downpipes after the turbos to reduce underhood temps a little but it's not going to give you performance gains to warrant the effort and added cost.

For the intercooler piping, you can certainly wrap that for some performance benefits...it'll just look butt ugly IMO. Personally, I'd trade a little performance for a cleaner under hood appearance unless it is a stripped out, gutted race car and every last pony is needed. In that case, everything would be wrapped, vented hood, A/C deleted, etc.