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turbo2nr said:
Is the turbo you are using also called a "Disco Potatoe":nanner2: ?

Last question. Is a pressure ratio of 1.5 about the same as 7.5PSI?
You have to take into account vaccum on the turbo inlet side as well so pressure ratio at that boost is about 1.7.

Also consider this: Airflow is just one piece of the puzzle. The engines VE makes a HUGE difference in what kind of power actually comes out of that airflow.

An engine with a VE of 98% will make LARGE gains over an engine at 80% VE.

A good example of this is the SRT4 and Cosworth Focus SVT. The SRT4 with 8.1:1 compression and "so so" breathing head makes about 220whp with 17psi of boost.

When turbocharging the 2.0 Focus engine with only 8psi, they made over 245whp. (Using the same GT28RS mind you).

The more efficient engine does more with less. VTEC Honda's with boost are a very good example of this. How many 400whp B18's are out there running only 15psi of boost. We also made 480hp with a built Mitsu 4G63 running only 16psi of boost on a GT35R turbo - THAT car was a monster when all was said and done. Nothing like 4wd drifts from a roll in third gear. :bow:

Technically, the 28RS compressor can flow about 33lbs of air at 1.7 ratio - but it's out of it's range to do that big time.
 

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PWR2W8 said:
Jay,

Do you have to change the oil pan when installing the turbo kit or is it just a good idea to do so? Need to know so I can make arrangements when my kit is being installed.

Thanks,

Brad
My take is this: If you are going to track the car hard, turbo or no turbo there may be some issues of oil starvation. Seems there are examples of about 50/50 either way that I can find. Some guys drive em harder than hard with no issues...others have problems.

Lotus chose to go with an accusump for this remedy on the Exige 240R and I tend to side with that solution myself as a backup safety precaution.

The turbocharger itself adds no more tax on the oil system as it flows a minimal amount of oil through it's center section and even has a built in flow restrictor.

Making the extra power obviously generates extra heat which in turn can create higher oil temps but thankfully Lotus has put in good oil coolers in a proper location. (Not stuck in a side vent as an after thought.)
 

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Discussion Starter #23
Jay when do you think you'll know if the Arquay Sport cat will work or not? Because if it won't I can drop off the stock cat on the weekend or an evening after work.
 

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Eyelise said:
I like hearing alternative views. Thanks for your contribution. I would really need to see the torque curve to better understand your statements. I can't get past the old familiar adage "small engine + big turbo= lag". It is not enough to produce more torque than NA everywhere. I want the set-up that will give me maximum torque down low and then a nice flat curve across a broad RPM range. I'm not as interested in huge peak numbers. Don't get me wrong, I'm looking for close to 300 whp but it is the delivery that really matters to me. Show me the torque curves baby.
Definetly different strokes for different folks. I've got both big turbo and small turbo cars in my life. Both have merit IMHO.

On the 1Z Toyota in our MR2 Spyder kit you can really see the different characteristics of the turbos when going from the 28R (rated from Garrett at 280hp) 28RS (rated 320hp) and the GT2871R (Rated at 385hp) all on the same turbo kit and car.

The 28R has lightening response and a linear pull from 2200-2300 to redline...very supercharger like feel.

Transient response of the turbo in part throttle driving is out of this world.

The 28RS has more of a "turbo" feel on the top end, a bit less responsive to the right foot but has a lot more "go" when you do mash the pedal.

The 2871 is a wait for it...wait for it...wait for it..HOLY CRAP turbo with real soggy throttle response.

It reallly comes down to throttle reponse and transient response IMHO.

I've noticed the 1.8 Toyota's for whatever reason do not come close to motivating a turbo like a 2.0 liter Nissan, Honda or Mitsubishi. We've got a GT30R on an SR20 powered SE-R here that is simply a monster and will build 12 psi of boost by 3200rpm and is in full swing by 4000rpm - better than a GT2871 on the 1Z/2Z. :shrug:

The K20 is a whole different animal. It's a very close relative to the Nissan SR20. It has a square bore and stroke (83mmx83mm) and head that flows like the dickens. (Over 300cfm stock!) It also has a pretty healthy bottom power curve end compared to the 2ZZ.

Eyelise: I think this is more the power curve you were talking about that you prefer.



That is from our Mazda 3/6 kit with the GT28R on the 2.3 liter Ford engine. WICKED responsive - Audi/VW like, but still pulls good on the top end. That's all you will get out of that turbo on that motor before it starts falling off on the top end. It's done with a capital D, BUT the car is a freakin hoot to drive.

This is a 2ZZGE with the GT2871 mentioned above at about 11.5 psi of boost.



The VE of the 1.8 Yota just isn't all that great on the small cam, and it really doesn't push a turbo that well. Not to say that 140ft lbs at 4000rpm isn't about 40 ft lbs stronger than stock but you can clearly see where the turbo comes up and the power and torque takes off. It's building boost down low, but the turbo doesn't swing into it's sweet spot till about 4700rpm.

That turbo is still streetable, but I would questions anything larger on a mid engine rwd car. Snappy power on one of these can spell trouble IMHO. It does for the MRS - ask me how I know. My rear quarter panel is primered for a reason.

Just my $0.02
 

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TurboXS_Nathan said:
What you want is a supercharger or a larger displacement motor. You will fail trying to make a turbocharged 2zz something that it is not. All respect to Hass and forced fed, but I think this motor will make more HP on less boost and be much more drivable at the track with the proper turbocharger.
None taken. I just don't agree that the 28RS is not a "proper" turbo. It's not like I havn't built GT35R Mitsu's or GT30R Nissan's etc etc. I have. Hell, we are about to boost a current generation Viper with probably twin GT3071's. :bow:

I think you might be surprised at how you find the 2ZZGE responds to larger turbos. I didn't pick the 28RS because I didn't know any better. I found it was the best turbo that could support 325whp comfortably and still offer excellent throttle response and boost response on the 2ZZGE, and I don't mean spool RPM.

There is nothing like squeezing on the throttle 25-50% at 3500-4500rpm in traffic and having the car just squirt forward right away with the turbo happily singing away and increasing the torque by a lot. It makes the car a joy to drive and the power delivery very predictable.

On FWD cars in road race situations, I would go the opposite route. The larger turbo cars have always been easier to drive as the boost comes up much more slowly and doesn't blow the tires off while in mid turn.

In the end, I am going my own way and building my Elise as I want to build it. I think others are missing out by not thinking outside the box, but it is their right. Time will tell who is right.
With all due respect I don't think it's a matter of right or wrong as much as it's a matter of preference. :)
 

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TurboXS_Nathan said:
You appear to agree with me then that a slightly larger turbocharger will be easier to drive in a road race situation with a little milder boost response. The additional benefit is that I should be able to make the same or better power on a lower boost setting all with less ignition timing required to light off the mixture. I am not building my car to feel like a viper or Vette. I intend to build it in such a way that enhances the track and street performance without overly changing the character of the car.
On a FWD car that makes over 300whp, you HAVE to have a laggy turbo or you end up plowing like a truck through the turns and it makes for a miserable and overall slower lap time than the guy with the NA car going 10/10ths with only 160whp.

That's more or less what I was getting at.

Here's a video of what I was getting at.

http://www.hassturbo.com/video/se-r/joes_car.mpg (This was at "light" boost BTW. ;) )

I owned an identical car to this one that I built and let me tell you - the car is all over the place at 110mph + grabbing for traction and can out run a Yamaho R1 from 50mph past 150mph. (The owner of this car actually owns an R1 and lost to his car on his own bike. ROFL) I was a MESS up at Limerock trying to muscle around the track and slower than the NA cars. LOL

As for the GT35’ed evo. It’s sort of a “fad” turbocharger. It’s not bad, but I prefer a 67mm/p-trim combo. That’s where the money is at (until you jump into the GT42 compressor wheel). Call me old school.
Well...I wasn't talking about the EVO. We were doing the 35R on DSM's back wheneverone was on the "Frank" and "color" turbos. It's recently become a "fad" because it's a NASTY turbo that can push out over 600whp and be very streetable. I will be putting a 30R with the .82 housing on my EVO as I'm not looking for those kind of crazy numbers.

I don’t think your turbo selection is so much “wrong” as it’s expected, in the box, what the market wants thinking. There’s nothing wrong with making your customers happy by giving them a turbo that spools wicked fast. I just think it’s the wrong choice for me personally. I don’t want wicked fast spool. I want linear (if increasing) torque with a much broader overall shape then stock.
Understood, thanks for clearing that up. :)

As for the 2zz low cam comments, have you ever tried a different manifold arrangement? There is value in your current setup as it gets the heat to the turbo ASAP, but I wonder if you are sacrificing exhaust flow and seriously harming VE in the process.
Not at these power levels. We take the time to makes the logs flow as best they can while taking advantage of the extra heat going to the turbo for a fat powerband. Our primaries are 1 5/8" and we do our best to place the flange so two ports have direct access to the turbine inlet and the other two are not fighting each other to get there. I.E. Putting the flange on the end of the log inline with the last port.

We've tried different set ups including a tight tubular unit and saw no real gain on the dyno at these power levels, sad to say.

I don’t think anyone can tell you that the 2zz heads don’t flow reasonably well.
Agreed, but I think the issues with the 2Z go beyond head flow.

Take a look at this dyno chart:



I was on throttle from the sample time starting and you can see it's building a little boost by 3500rpm with about 6psi by 4000rpm and then going into full swing at about 4700rpm. The turbo was building boost down low, but the engine simply was not responding very well to that boost until it was past 5K rpm.

That's the scenario you were talking about using a large turbo with light early boost onset and I hope you don't see the same results. That was with the GT2871R BTW. Just passing along some info - not trying to discourage you at all.
 

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TurboXS_Nathan said:
Conventional wisdom says you can't run boost on a 11.5:1 motor without blowing it up. I guess we'll just have to wait and see. I am obviously willing to bet my motor that I can make this work.
Oh sure you can. I'll be your biggest supporter for that. :)

FYI: I've been past 15psi on pump gas using a 1mm water jet. I don't dare tell customers to do that, but it doesn't change the fact that the stock 2ZZGE was pretty damned okay with it believe it or not.

The ignition system bitching up a storm trying to light the fire at that boost with water was another story. LOL
 

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crackaonrice said:
what turbo is it actually? is that a gt28r?


very nice tuned curve

http://www.hassturbo.com/images/2z-327hp-dyno.jpg
If you are referring to that dyno run, it was on the GT2871R. The kit uses a GT28RS which will yield very similar results up to about 320whp with a little more response down low.
 

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MyElise said:
I think you will be surprised. A number of the kits purchased are going onto cars which will see a lot of track time. Nothing wrong with drag cars or street racers but I don't believe that the track car is looking to maximize hp and torque. I'm looking for that extra 40 lb/ft of torque between 4k and 6.2k to pull me out of the corners and the extra 50 hp for the straights. I hope 6 psi will supply that without significantly upsetting drivability, reliability, throttle response or handling.

Frankly I'm shocked at how many guys are tracking their car. By FAR the Elise community is the most hard core I have delt with regarding actual use of their cars and wanting to drive them around a track. Out of the five cars we currently have in our shop three are going to track them. I would say at least 70% of the kits we have sold to date will be on a road course.

I think the low boost option you are talking about will be a pleasant surprise. The most common feedback I have gotten at 6-7psi is "wow, it still feels like the NA car in regard to power delivery - just a lot more of it."

Once you get into the higher boost range, the power delivery is more tied to the boost gauge so you feel that "rush" come on when the boost dial swings towards the big end.

The light weight of the Elise is also an asset to this nature. My EVO by comparison is a heavy bitch. Off boost, the car is dead as you are trying to move 3300lbs with 122ci. It's not until the boost gauge swings past 15psi does the car get up and go. It really makes for an "on/off" type car as it NEEDS that boost to make enough power to get out of it's own way.

With the Elise and low boost it accentuates the already balanced nature of the car while fattening up the powerband across the board so you can punch through that hole and not have to flat foot the car and painfully watch the tach and speedo creep up slowly on the top end.

Bah...you guys will just have to start driving them and report back with your own experiences. Trying to talk about it is like trying to explain sex if you've never had it. LOL :D
 

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Discussion Starter #30
MyElise said:
Enough of this nonsense. Scotty, what is happening with the car?
All this is quite amusing! Anyways no updates this weekend, I'll hopefully touch base with Jay on Monday. My main concern was whether my Arquay Sport CAT can be modified for the turbo. If not, He's going to have to take my Stock Cat and work that into my Arquay SS Dual Tip Exhaust.

Also something quite interesting, Jay thought that the Arquay Sport Cat might actually be more restrictive than the stock CAT. Any one have any info on this. All I know is the Arquay CAT is lighter.
 

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Stan said:
Have it measured...you can make a fitting to screw into the O2 sensor bung and then use a normal pressure gage.
Exactly, the problem is finding a flowbench that can flow like an engine! LOL Most can replicate one port at a time but to simulate an engine on WOT takes a lot of huff.

The comment was a casual observation. The sport cat has a much smaller overall area compared to the stock unit, but the "cells" look larger so it may be a wash. I really don't have any hard proof for the record and don't want misinformation to get out about the product.

I'll see what I can come up with, but the shopvac test isn't going to be very much help IMHO. :p Maybe we can rig a turbo compressor on a 12hp briggs and stratton to make our own industrial strength blower. LOL
 

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Discussion Starter #32
Here's my latest correspondence from Jay:

"The coated intercooler is supposed to be here late today, that's is the last piece of the puzzle we were waiting on to finish bolting the turbo system up. So we will be back in full swing on Friday to get her buttoned up regarding the turbo."
 

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Ryno said:
Thanks. I'm looking at a similar situation with an out of town install.
So the question is can you get all the way on it right away or is there any break in required?
The only real break-in period is for new engines. If the engine hasn't been broken in as per Lotus/Toyota suggested period you cannot just slam it with full boost and throttle. If your engine had already been broken in properly then you can use the turbo to full performance immediately after install. Although you would be wise to take it easy and check things for athe first few days to ensure all things are working properly and secured.

The 500 mile break-in Sky-King was requesting was not so much for the actual engine break-in but rather to give Hass some time/miles with the car to ensure proper ECU tuning and component reliability. It was more of a Turbo System trial period to help uncover unforseen problems before being delivered across the country.
 

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Discussion Starter #34
Well I dropped in on Jay unannounced today. He's swamped but things are looking great. My Elise is coming along great. I saw the powder coated intercooler and was amazed on how OEM it looked. Jay still needs to section my Arquay Sport Cat so that the system will work with my Arquay SS twin Tip exhaust. We are hoping to have the car at the Dyno next Wed if all goes well. Unfortunately I didn't have my camera so I couldn't take any pictures.
 

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Discussion Starter #35
avantephoto said:
Hi Scotty,... was curious to know if you could elaborate a bit more on what the "work" was to get it to fit with your exhaust?
Well the position of the chamber on the Arquay Sport Cat is closer to the manifold than the stock CAT. Since he is replacing the stock manifold with his own that has the turbo attached, the position of the cat is altered. Essentially he is going to have to section the Arquay Sport Cat in front and behind the canister. He then is going to have to weld new pieces to get it to work correctly with my Arquay SS dual Tip exhaust. Not difficult, but a PITA. I opted to have him do this rather than use my stock CAT because I want to have the option of returning to Stock. This way I will still have the stock manifold, CAT & exhaust.

avantephoto said:
Also... the tuning that they did on Skyking's car where they gained a bit more power... did Jay say if that work/knowledge was going to be put into your e-Manage?
He didn't say anything about the emanage. Jay did say that Skyking wants him to up the boost and see how much this system can handle. Jay did have a big devious smile that spread from ear to ear when he told me this. :evil:
 

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Discussion Starter #36
1FASTMX5 said:
My Lord...his shop must be over-filled with Elises at this point :D . Im sure he can't wait to clear some of them out of there by now. Hey Jay, I hope you got enough insurance for the mini Lotus Dealership you got :eek: :D
Yea it's crazy there right now. I think he wants to start charging you and Skyking rent. rotfl

1FastMX5 I saw your car there too. I don't know how you have made it through all this time without your car. I'm going crazy and it's just been 1 month for me. Looks like your having a fun time with that PB Wing of yours. What's happening with that?

It looks like XCUSEMI will have the distinction of being the first Hass Turbo on the road. His car is nearly finished. I think Jay's just waiting on one part to come in so he can button her up.
 

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scottyb said:
Yea it's crazy there right now. I think he wants to start charging you and Skyking rent. rotfl

1FastMX5 I saw your car there too. I don't know how you have made it through all this time without your car. I'm going crazy and it's just been 1 month for me. Looks like your having a fun time with that PB Wing of yours. What's happening with that?

It looks like XCUSEMI will have the distinction of being the first Hass Turbo on the road. His car is nearly finished. I think Jay's just waiting on one part to come in so he can button her up.
Oh trust me I want my car back very badly! I have lost a whole year of driving due to the issues of the previous install. It's crazy, I have owned this car since 08/04 and I am barely familiar with it as I only had it for a couple of months. When I get it back It will be like getting a whole new car again.

Jay, I'm ready to take it off your hands whenever you are :D

The new PB wing should be there by now and hopefully will have no more issues and can be quickly installed. I'm so ready to get her back!
 

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Discussion Starter #38
Jay gave me a call today to let me know that he’s trying to figure out what to do with my Arquay exhaust and CAT. It wouldn’t be a problem if I chose to go without the CAT, but I don’t want to have any issues when it comes to emissions. No one is really sure what’s going to happen in CT yet when it comes to this. So it looks like he is going to have to alter the piping on both the cat and exhaust to get it to work with his turbo set up. Hopefully we’ll know whether the system will work with the Arquay Dual SS Tip sometime tomorrow. If not, he will source out a new CAT & Muffler that will exit the rear like the Euro 111S.
 

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Discussion Starter #39
I spoke to the Lovely Keely a few moments ago and was informed that the Arquay Surgery was successful. :nanner:

Jay had to section some of the Arquay piping to get it all to fit together with his turbo manifold.
 

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Discussion Starter #40
Got some pictures from Jay today. My sport Cat finally got back from the powder coater. Also, Jay's working on a custom gauge pod for me that will go on the shelf on the dash. It will house three gauges. I'm also thinking about having 2 gauges mounted vertically in front of the shifter. Do you guys think it will be too busy?
 

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