evo 3 16g vs new fp 18g

[JayRolla]

I was thinking about putting higher compression pistons in my 1g/6bolt which is equipped with DSMLink, but anyway do 8.5:1 compressions pistons make that much of a difference? I was thinking about 8.8:1 with my Evo III turbo setup. But depending on what you have to say I may just keep the stock compression ratio.

In short is it better to have 7.8:1 compression and more timing, or less timing and 8.5/8.8:1 compression?

Well if you where going to upgrade the pistons to forged ones I would go with the 8.8:1. With dsmlink you wont have trouble tuning since you can pull timing.

 

[JayRolla]

I don't know about this, a 7cm housing isn't "that" small. And the turbine wheel itself is midway between a TD05H and a TD06. I run a restrictive turbine housing/wheel on my T28, thats has some serious exhaust backpressure.

It usually doesn't affect knock so much until you upgrade to a cam setup that has some overlap, like my HKS 264's, then from my experience you start to see a lot more knock from the backpressure. Before cams I actually ran 25 psi on pump gas on my tiny T28 on a 70-80*F day, a little knock to be sure but only a couple degrees pulled back. Car loved it and made big torque. Once I went to cams the car "hated" big boost and knocks at anything over 21 psi on pump, though in winter it maybe can run up to 22 psi.

Everything is so dependant on the "system" tune, his knock is hardly anything from his last data log, though its impossible to tell how bad it could get cause the timing is still low.

Whats cracking me up is that from what I'm reading, guys are expecting big power numbers from pump gas levels of boost, say 21-22 psi. It don't work that way, you need big boost to see the bigger airflow numbers that make the 50 trims or whatever standout. Your average 2.0L is only going to flow 40 lb/min at 6500 rpm on 20-21 psi. You want another 50 h.p. its going to mean bumping the boost up to 25 psi or building the motor to produce a power peak higher up in the rpm band.

This is why most average cars don't show a major difference in power between turbos at your average 20 psi daily boost setting. Crank that 18g up to 25-27 psi, dump in some high octane, jack the timing up, and add cams, then you'll start seeing a low-mid 400 h.p. run.

I wouldn't go blaming the turbo if the above mentioned things aren't done, I'd blame my own conservative tuning and lack of supporting mods.

Its pretty much been proven that the 16g housings are too small and thats why you cant get more than 17-20psi on pump gas on stock timing maps. Causes too much detonation. Now stuff even a bigger wheel in that housing and lets see whats going to happen.

I dont think that 18g wheel will be too efficient on pump gas and wont make much more than the 16g. Now add some race fuel and people are talking about 400hp numbers, which the 16g can do with better spool.

There is a guy that made 450whp on a 16g running e85. Why buy a turbo for so much more money that does not out perform the 16g. It may push a little more air but its minimal. Only thing I see it being better is maybe pushing more air at higher boost levels but since its running the 16g housings you would think that would cause it too choke out and not hold high levels of boost. Also maybe cause it to surge.

 

[chavez408]

So in the end, this turbo would be good for the avrg tuner comming off a stock turbo (14b,t25,13b..) And looking for a quick upgrade.
And someone who is looking for minm 300whp? With its supporting mods.

 

[gdmbat85]

So in the end, this turbo would be good for the avrg tuner comming off a stock turbo (14b,t25,13b..) And looking for a quick upgrade.
And someone who is looking for minm 300whp? With its supporting mods.

Yea, that's pretty much a good way of putting it. This turbo is a good alternative for an evo3 for someone upgrading from stock (like me) and looking for a little more than an evo3. This is the perfect turbo for people that don't plan on going crazy. I, unfortunately, have to deal with a friend getting a turbo kit for his trans am, so it's now becoming a grudge match for dominance. If anyone would like to donate to the cause, I'd be more than happy to accept,

 

[Black_Bullet]

I don't know about this, a 7cm housing isn't "that" small. And the turbine wheel itself is midway between a TD05H and a TD06. I run a restrictive turbine housing/wheel on my T28, thats has some serious exhaust backpressure.

It usually doesn't affect knock so much until you upgrade to a cam setup that has some overlap, like my HKS 264's, then from my experience you start to see a lot more knock from the backpressure. Before cams I actually ran 25 psi on pump gas on my tiny T28 on a 70-80*F day, a little knock to be sure but only a couple degrees pulled back. Car loved it and made big torque. Once I went to cams the car "hated" big boost and knocks at anything over 21 psi on pump, though in winter it maybe can run up to 22 psi.

Everything is so dependant on the "system" tune, his knock is hardly anything from his last data log, though its impossible to tell how bad it could get cause the timing is still low.

Whats cracking me up is that from what I'm reading, guys are expecting big power numbers from pump gas levels of boost, say 21-22 psi. It don't work that way, you need big boost to see the bigger airflow numbers that make the 50 trims or whatever standout. Your average 2.0L is only going to flow 40 lb/min at 6500 rpm on 20-21 psi. You want another 50 h.p. its going to mean bumping the boost up to 25 psi or building the motor to produce a power peak higher up in the rpm band.

This is why most average cars don't show a major difference in power between turbos at your average 20 psi daily boost setting. Crank that 18g up to 25-27 psi, dump in some high octane, jack the timing up, and add cams, then you'll start seeing a low-mid 400 h.p. run.

I wouldn't go blaming the turbo if the above mentioned things aren't done, I'd blame my own conservative tuning and lack of supporting mods.

This is pretty fair information but I agree with jayrolla as far as the evo3 compressor side is just too small for high boost high rpm, people who use race gas and meth can eck the power our of it since that fuel can deal with the heat and they can normally squeeze max timing advance out of it as well but it still doesnt hide the fact of the limited potiential of an compressor this small.
As far as cams making it knock more, its causing a lot more air flow and basically meaning its just maxing out the "heat thresh hold" at a lower boost level and thats why your car would knock at 21psi with cams were as wouldnt with 25psi without cams... On a small turbo the lbs per min of airflow difference between 21psi- and 25psi isnt that big a difference even if it feels like it is ( in this situation you tend to feel the torque gains), the actual air flow gains get smaller and smaller the higher you go up, but 21psi with cams vs 21psi without cams will net a much bigger difference in flow. Your just getting the same heat but at a sooner time is what im saying. Cams with extended ramp rates like the fp x series cams tend to cause much more combustion pressure due to somewhat increased dynamic compression leading to more knock. According to a memeber on this forum ive spoken with DarenP, about this, he could run like 22-23psi before fp1x cams, and limited to 18lbs after fpx cams but making more power...

I was thinking about putting higher compression pistons in my 1g/6bolt which is equipped with DSMLink, but anyway do 8.5:1 compressions pistons make that much of a difference? I was thinking about 8.8:1 with my Evo III turbo setup. But depending on what you have to say I may just keep the stock compression ratio.

In short is it better to have 7.8:1 compression and more timing, or less timing and 8.5/8.8:1 compression?

On pump gas if a lot of boost and timing was the goal, id keep the compression low, like 8.3:1 - to 8.5:1 wiseco or something, honestly the 1g compression ratio isnt all that efficient to begin with. Now if theres meth or race gas, or E85 in the pic why hold back the power. Id say go for 9:1 if you have meth or E85 all the time. Or stay 1g compression if you want to play it safe... Its all in tuning and octane though. The dynamic Compression has to be determined by a number of factors though, type of fuel used, volmetric efficiency of the motor, the engines stroke, camshafts , how much boost used, timing maps ( 1g timing maps dont like high compression as Jayrolla mentioned, especially with the 6k timing spike.) someone else might know the answer to this better for what compression you should do, im just throwing out my thoughts.

Yea, that's pretty much a good way of putting it. This turbo is a good alternative for an evo3 for someone upgrading from stock (like me) and looking for a little more than an evo3. This is the perfect turbo for people that don't plan on going crazy. I, unfortunately, have to deal with a friend getting a turbo kit for his trans am, so it's now becoming a grudge match for dominance. If anyone would like to donate to the cause, I'd be more than happy to accept,

Basically like I was thinking...

 

[dsm-onster]

Its pretty much been proven that the 16g housings are too small and thats why you cant get more than 17-20psi on pump gas on stock timing maps. Causes too much detonation. Now stuff even a bigger wheel in that housing and lets see whats going to happen.

I dont think that 18g wheel will be too efficient on pump gas and wont make much more than the 16g. Now add some race fuel and people are talking about 400hp numbers, which the 16g can do with better spool.

There is a guy that made 450whp on a 16g running e85. Why buy a turbo for so much more money that does not out perform the 16g. It may push a little more air but its minimal. Only thing I see it being better is maybe pushing more air at higher boost levels but since its running the 16g housings you would think that would cause it too choke out and not hold high levels of boost. Also maybe cause it to surge.

Do you mean turbine housing or compressor housing?

Compressor efficiency has a minimal influence on pumpgas tunes where proper intecooling is used. A 75% efficient intercooler (ebay fmic) is plenty efficient to run a compressor at 65% efficiency (terribly off the map) and will keep aircharge within about 5 degrees of a compressor running at 70% efficiency. A smaller compressor a/r also increases efficiency at higher boost levels according to Garrett. And performance differences are minimal.

The turbine housing airflow cannot be discussed w/out mentioning the turbine.
For example, the t-bird TC runs a .48ar t3 turbo (automatic) and .63 ar t3 turbo (manual). We swap in the 1985 GN CHRA which has the same turbine but larger t compressor. We manage to wring out 300whp. The same .63 turbine housing machined to accept a t3 stage 3 turbine coupled to that GN compressor yields 350whp. Same boost. The turbine flows more. And the .63 ar turbine housing has never been labled a restriction to 500whp 50 trim setups. The 7cm^2 turbine housing can flow enough for that hp, see FPgreen and FPred. The housing size is a way to fine tune a setup for topend or slightly quicker spool.

The td06 turbine wheel causes the whole turbine to flow more. Having a 7cm^2 turbine housing does not choke it. td06h 20Gs have been banging out big airflow numbers for years. The compressor housing can be restrictive. But, FP feels that it is OK for the 18g wheel.

You really shouldn't state the flow difference between the 18g and the evo3 16g compressors is minimal. . . We have no proof. That is why this thread and several others have begun. We have seen many evo3 16Gs pushed far beyond their rated maximum airflow. Understanding how the housings influence performance, why would a turbo using a larger turbine and significantly larger compressor w/ the same blade shape flow marginally more?

 

[chavez408]

I would want to see the difference in gain when meth is install.

 

[pboglio]

Wait a minute. The 18g has such an inefficient compressor wheel in the TD05H compressor housing, a restrictive 7 cm turbine housing, and of course a "restrictive" TD06SL2 wheel that causes a car not to be able to run more than 17-20 psi without knocking. So guys prefer the EVOIII 16g to that? The EVOIII 16g runs a nonclipped TD05H wheel which has been known for the last 15 years to be so restrictive on a 20g that a MASSIVE clip of the turbine wheel is required.

Things aren't adding up. 18g flows LESS than a 20g on the compressor side, yet arguably the TD06SL2 wheel flows more than a TD05H wheel. I'm not understanding what the problem is with this combo? Who on Gods earth wants to run anything bigger than a 7cm housing. Everybody that runs an 8cm switches right back to a 7cm cause of the lag.

Common sense guys, if you can't run more than 17-20 psi on pump gas on a 18g with a turbine section that frikking big, one of the last things to blame is the turbo. I do it on my T28 all day long, on a lot more timing than stock and on 8.5:1 compression. It ain't the turbo causing the problems.

 

[dsm-onster]

Common sense guys, if you can't run more than 17-20 psi on pump gas on a 18g with a turbine section that frikking big, one of the last things to blame is the turbo. I do it on my T28 all day long, on a lot more timing than stock and on 8.5:1 compression. It ain't the turbo causing the problems.

AMEN! I actually have a semi-decent tune w/ a small 16g and pump gas running 20 psi now (NO injection)! It took lots of time. This is the typical small 16g (td05h 7cm^2 turbine). A larger turbine wheel would net my airflow goal at a lower psi, with or without the 7cm^2 housing.

 

[pboglio]

It does look like the map for the EVO 16g compressor and the 18g look really close in terms of maximum flow capability, with the peak efficiency island advantage going to the 18g. Both turbos on their 130,000 rpm speed line max right around .295 m^3/s (622 cfm). The EVO does it at a pressure ratio of 2.35 (19.8 psi) while the 18g does so at 2.15 (16.9 psi).

From the maps I don't think an 18g wheel flows any more than an EVOIII 16g compressor wheel, but the bigger turbine wheel alone has got to be worth another 20-30 h.p. in decreased exhaust backpressure.

 

[dsm-onster]

It does look like the map for the EVO 16g compressor and the 18g look really close in terms of maximum flow capability, with the peak efficiency island advantage going to the 18g. Both turbos on their 130,000 rpm speed line max right around .295 m^3/s (622 cfm). The EVO does it at a pressure ratio of 2.35 (19.8 psi) while the 18g does so at 2.15 (16.9 psi).

From the maps I don't think an 18g wheel flows any more than an EVOIII 16g compressor wheel, but the bigger turbine wheel alone has got to be worth another 20-30 h.p. in decreased exhaust backpressure.

There is no map of the evo3 16g. There is a map for the evo4-8 td05hr 16g, there is a map for the big 16g. And recently FP released the map for the 18g. . .

 

[pboglio]

There is no map of the evo3 16g. There is a map for the evo4-8 td05hr 16g, there is a map for the big 16g. And recently FP released the map for the 18g. . .

Your absolutely right. I used the TD05HR-16g6 map as a substitute for the EVOIII map. That might not be a valid assumption as the EVOIII was already superseded by the TD05HR-16g6 and there might have been flow improvements between revisions. I think its safe to say from the maps that the 18g closely matches the TD05HR-16g6 in terms of performance of the compressor. My point is from a technical standpoint, the FP 18g/TD06SL2 already appears to be an improvement over the EVOIII 16G

Just curious, what kind of airflow are you seeing from the 16g at those boost levels. If you got a log post it up.

 

[dsm-onster]

Can't log w/ dsmlink my laptop is beyond repair. I tried w/ a comical result to log w/ my home pc in the car once.

I've been using my scanmaster. I reach 1606hz by 6K. That is as far as the scanmaster logs hz count. I rev to 7500. I bring the car home to plug into the pc instead of 'tuning on the fly'. I've retarded my timing at 2500rpm by 2 degrees and 1 degrees at 3K rpms and the rest is stock timing. I start leaning out at 4500rpms 5 percent reaching 13 percent by 7500 rpms. I see 0-3 counts of knock at random pulls in 3rd gear.

I've been seeing more knock up top recently. Being that I'm running a hacked 1g maf, I'm sure I'm reaching the fringes of overrun.

My point is from a technical standpoint, the FP 18g/TD06SL2 already appears to be an improvement over the EVOIII 16G

I agree. I even feel that the td05h turbine is too small for the evo3 16g. I feel that an 8cm^2 turbine housing (there is none for a tdo5h turbine), or a housing like the BEP, is much better for the evo3 16g compressor; or this "new" turbine wheel. At least it merits a mild clip.

This 18g could only be better with this new turbine wheel.

 

[chavez408]

Dang you guys lost me! Way too advance for me haha

 

[dsm-onster]

Ispent some time on my car today to get a log up. Using my sanmaster, the narrow band o2 was showing .75 volts a 20 psi. I'm running walbro 255 and 1000cc injectors.My FPR shows a 1:1 rise. So I'm sure I was experiening maf overun. Though one should swear by their oem o2 sensor, my fuel curve was close to stock.

No more blown headgaskets for me. So I readjusted my MBC, zeroed out my fuel and timing, and braced my home pc very well in the car; and I took her out for a run. Peak boost is around 15 psi. Small 16g. Pumpgas. FMIC, FP2xs, stock valves, stock intake manifold, evo3 exhaust manifold. I recorded 30.2 lbs/min at only 15 psi (around 320 hp). I truely appreciate this little turbo!

My boostest curve is NOT in line w/actual boost. I see boost much quicker.

Nevertheless, You can see there's lots more room. Even on pump gas. Considering the larger FP18g turbine wheel, over 350whp (34 lbs/min) on pump gas should be a cinch!!!

 

[pboglio]

Nice pull, pretty good airflow for 15 psi. I had a small 16g with a 10* clip on my 91 eclipse and the topend was awesome. I kinda wish I had that one on my 97 GSX now but I like to experiment.

A little outside the topic, but here's a log of my FP T28/28 on 24 psi spike dropping to 21 psi of boost. Mods are in my profile but I'm running a dead stock 2g MAF. With the colder weather, I'm hitting around 37 lb/min max on my T28. Power wise its leveling off right around 350 h.p. crank. I'm fighting a massive amount of backpressure in the turbine housing at this point and cranking the boost more increases torque a little but it costs me high rpm power.

My current turbo is done, stick a fork in it I was thinking of pulling the turbine wheel off and getting it clipped 10* but it isn't worth the hassle for an extra 10-15 h.p.

 

[dsm-onster]

I agree. The clip isn't worth it. Great pull! Get a 50-trim .

I forgot to mention that the pull I posted was in first gear (speed was 37 mph). You peaked out at 37 lbs/min at 65 mph. Isn't that peak airflow w/ a second gear pull?

 

[pboglio]

Yeah, 2nd gear pull. I prefer 2nd gear as the speeds stay pretty tame. I've done a lot of 3rd gear pulls in the past when I lived next to the forest preserves with no cross streets. But now where I live a 100mph 3rd gear pull to redline would be criminal.

Yeah, I'm deciding between a BB 50 trim, Blouch T28/40 (aka GT2871), FP3052, or the FP 18g. Far and away the 18g provides the most h.p. per dollar and puts me comfortably into the 400 h.p. range I'd like to be in. I'm looking for a 117-118 mph trap, maybe 120 mph with some weight removal.

 

[chavez408]

Sbr g50! Can't beat the price $660 I believe?

 

[pboglio]

Sbr g50! Can't beat the price $660 I believe?

Yeah, $679 internally gated. I've heard they are laggy at part throttle so that one is out of the question for me.

 

[chavez408]

21+- psi at 3800rpm from what I search. Its not bad at all

 

[dsm-onster]

pboglio is likely concerned about transient boost response. Which dosn't really show durning a single, "prepared" pull. The typical 50trim would have less transient response than a BB 50trim or the other turbos on which he's debating.

 

[gdmbat85]

Yeah, 2nd gear pull. I prefer 2nd gear as the speeds stay pretty tame. I've done a lot of 3rd gear pulls in the past when I lived next to the forest preserves with no cross streets. But now where I live a 100mph 3rd gear pull to redline would be criminal.

Yeah, I'm deciding between a BB 50 trim, Blouch T28/40 (aka GT2871), FP3052, or the FP 18g. Far and away the 18g provides the most h.p. per dollar and puts me comfortably into the 400 h.p. range I'd like to be in. I'm looking for a 117-118 mph trap, maybe 120 mph with some weight removal.

I can vouch for the GT2871. My friend had it on his stock longblock SR20 (2.0L) 240sx. He was running 20psi and it felt like there was less turbo lag than my stock T-25. Pardon the french expression, but it pulled like a raped horse all the way to redline. He dynoed 330WHP on a conservitive tune. I hope that helps as to what to expect from a GT2871.

 

[chavez408]

so pboglio are you regretting on getting that 18g? looks like your a little bit disappointed

 

[pboglio]

I can vouch for the GT2871. My friend had it on his stock longblock SR20 (2.0L) 240sx. He was running 20psi and it felt like there was less turbo lag than my stock T-25. Pardon the french expression, but it pulled like a raped horse all the way to redline. He dynoed 330WHP on a conservitive tune. I hope that helps as to what to expect from a GT2871.

I can believe it and thanks for the first hand input. The only difference is that GT2871 on your buddy's 240sx probably had the garrett style turbine housing, which they have tons of options for A/R. This one I'm looking at would be installed inside the guts of a T28 and be stuck with a .48 A/R ratio, making installation a breeze but would be very restrictive on the hot side.

Performance wise from what I read the compressor on the GT2871 is very similar to an 18g, choke flow around 42 lb/min. Personally, going full garrett opens up "enormous" options for tuning the hot side, something like 5 different A/R turbine housings which I currently can't do. At that point I can get away from needing to depend on DSM specific vendors. A T3 exhaust manifold from Turbonetics, which is kinda similar to an FP race manifold, makes it possible aside from some custom downpipe work which isn't a big deal at this point.