gt4088
68 pounds @ 19 psi

58 @ 14.7

602 and 514 at crank SAE hp


GT3582r
68 pounds at 19 psi

63 at 14.7

602 and 558 at crank SAE hp


GTX3582r
75 pounds at 19 psi

68 pounds at 14.7 psi

664 and 602 at crank SAE hp

all above from Garrett compressor maps...

howard

do you mean that the smaller GT35R will produce more power at 14.7psi than the bigger GT4088??

The GTX is a brilliant unit but a bit expensive for my budget...

What does SAE mean

Also I can tell you for a fact that an FD with a GT35R @ 1 bar will not do more than 430 @ the crank

"do you mean that the smaller GT35R will produce more power at 14.7psi than the bigger GT4088??"

yes. the 4088 isn't able to make as much air as the GT35 at lower boost levels as per Garrett...

SAE is the generally (USA) acknowledged correction factor. dyno runs correct for non standard temp, pressure and humidity. if you use different correction factors you produce differing hp output.

dear Mr Howard Coleman CPR you seem to know quite a bit about turbos. Can you have a quick look at my post and see if you can help me out...

https://www.rx7club.com/single-turbo-rx-7s-23/hks-t04e-935395/

thanks again

done:)

This information is Golden. Saved in the databank... I never forget this stuff either. I will remember this 10 years.

I know , Mr Howard Coleman CPR is a treasure to this forum . Merry Christmas and a happy new year to EVERYONE

i hate to bump this 2.5 year old thread, but i'm wondering if anyone has seen a compressor map (much less plotted a ported 13b on the map) for a Precision 6262 turbo?

i have a blown up GTX35R that i am replacing with a 6262 .84, and i'm wondering about the difference between the two turbos.

After so many months , even years I still have the small T04E by HKS. I have seen 23 and 24 psi but I wonder if my small unit is already maxed at 15psi....

I came across two interesting turbos... One is a second hand GT3582R with T3 0.84 A/R hotside
This is sold at 500 euros which is about 650 us

The second option is by Turblow named TDX61R and has a very interesting NON ball bearing unit at 1000us dollars with the following info

The Turblown TDX61R is arguably the best street, and medium frame turbo for a 2 rotor engine. This water-cooled Ball Bearing turbo provides the fast spool of our standard TD61 Turbo(61mm-500rwhp), with the power of a To4Z Turbo(67mm-550rwhp). This turbo features A TurboSource 11 blade 61mm billet compressor wheel. It " spools" 500rpms faster than a TO4Z while still being able to support 550rwhp @ 25+psi( E85 or race gas). The turbine section is a 74mm P trim wheel, which is very well suited for the 15 to 25psi range on a 13B 2 rotor. The larger 74mm P trim wheel outflows the 68mm Gt35R turbine wheel considerably above 18psi. We have seen as much as 24psi by 3400rpms in 4th gear on the dyno. Most end users report 400rwhp @ 15 psi, and 15psi by 34 to 3600RPMs.

To me it looks like a GTX 3582R compressor and wheel without the ball bearings but with a more efficient cold side...

My aim is 500bhp (engine) at 20psi

Howard what do you think of the TDX61R

Regarding my setup do you think that my cast iron HKS exhaust manifold and HKS 40mm external are small and not efficient any more for the bigger turbos I have in mind

I some some tubular exhaust manifold sold on ebay for cheap money...Are they any good???

92-99 Mazda RX7 FD3S Turbo Exhaust Manifold | eBay

This is a very nice option as well!!!

Precision SC6262SP Billet Turbo NEW SC6262 T4 Divided | eBay

Any comments on my last two posts ???

objective: 500 hp

960 CFM or 66.3 pounds air per minute

you have a TO4E 60 trim.

the TO4E was a family of compressors before Garrett released the GT line. progress in turbos since early 2000s has been significant.

in 2003 when i designed my twin turbo setup i was looking for an efficient 80 pounds per minute. i decided on two TO4E 46 trims which each put out 44 pounds per minute. they worked very well.

your HKS kit uses a Garrett TO4E 60 trim compressor

TO4E 60

46.5 pounds per minute at 14.7 369 hp
50 pounds at 19.4 psi 377 hp

compressor average area: 5.64 sq inches
the GT35 compressor is 6.386

your turbine area is 5.89 (P trim)
GT35 turbine area 5.171

you have a pretty small hot side housing given it is a T3. i have a fair amount of experience as i was running two TO4s and had to move to two of your T3 housings to get back pressure where i wanted.

keep in mind the rotary requires more airflow to make equivalent piston hp. that means the hotside needs to be larger. the rotary also generates approx 400 degrees more EGT. you need to get that out of the engine so hot side sizing is important.

your current turbo has a really nice hot wheel and a restrictive housing.

as to looking for a new turbo...

first off....

you can do 500 w a "small" size turbo or a "medium" size turbo.

if you do it w a small size you will be pushing it to close to it's limit and you may gain some midrange advantage.

if you choose mid size your turbo will be cruising, not stressed, and you will lose a small amount of midrange.

as always, life is filled w trade-offs and YOU have to make the call based on your needs.

the turbos you list are in the small category. that doesn't mean they don't make major power, just relatively, they are smaller.

all three have compressor wheels that are in the 6.3 average sq inch area.

they do differ greatly.

the first mentioned has too small a hotside for your app. period. too much back-pressure, too much retained heat. warped apex seals.

the second (TDX61r) would be my choice based on dimensions. it has an uprated GT35 compressor wheel and a P trim sized turbine wheel. less back pressure. less retained heat. less warped apex seals. the write up is for the BB version but Turblown sells a journal bearing model which is more cost effective.

caveat: i believe Turblown was testing their own billet compressor wheel on this turbo. being conservative, i would prefer a Garrett GTX comp wheel. should the in-house wheel prove out i would give it a look.

a properly built journal bearing GTX35 compressor, or equivalent, paired w a P trim sized turbine wheel, w a T4 divided housing might just be the current best answer for many FD apps.

just keep in mind that anything above 500 hp and you will be pressing this turbo.

Elliot might want to give us some info on what he is using for a comp wheel...

the Precision turbo you mention has Precison's proprietary billet comp wheel which is the same approx size (6.386 area) as the other two... Precision is a non OE turbo vendor (unlike Garrett/Honeywell and Borg Warner) and as such may not have the resources to provide compressor maps.

that doesn't mean we can't evaluate their product. lots of dyno and track attest to their outstanding performance.

do keep in mind when you are looking at their data as to HP the Precision, as well as all others, are talking piston.

for example a "700" hp turbo is 700 FW piston.

to get the rotary number we can divide by 1.3

700/ 1.3 = 538 rotary as an example

the Precision turbo you mention has a GTX type compressor w a hotside wheel equivalent to a Stage 5 T3

5.408 average hot side area.

so, turbine larger than a GT35 but smaller than a P trim.

rotaries need all the hotside they can get in the 500 hp area.

i would add another turbo for your consideration in the "small" category:

Borg Warner

P/N 177272
P/N 177280 same w a 90 degree bend towards front comp housing

compressor area 6.437 V 6.386 for GT35

hotside wheel area 6.31 V 5.171 V 5.89 V 5.408

T4 housing w 1.00 A/R avail



moving to the "medium" category

most have compressors that measure 7.0 average sq inches.

many have high trims in the 63 area (favoring top end V mid range)

an exception is the Borg Warner mid size which has a 52 trim

BW

P/N 177283

compressor 7.06

hotside wheel 6.31

this turbo will make 550 and be on cruise at 500 around 20 psi. it will make 400 rw rotary at 5500 so it has kick ass midrange and was happy on my motor around 8650.

all of the above are available w P/N 177209 which is a 1.00 A/R rear housing

for an extensive list of brand of turbos and their wheel sizes see my sticky thread in the Turbo section. "Turbo Comparisons."

as to your manifold...

i doubt you will hit most of the hp numbers (which are approx max) w your manifold. it has a flow problem. manifolds are really important as to configuration and i will have a lot to say on the subject down the road. there are many manifolds on the market and most will work better than the one you have. it is unfortunate that HKS didn't put much effort into the design as cast manifolds are superior to tubular in many respects.

happy hunting,

Howard

EDIT: Just realized that Howard pointed you towards the exact turbos I am talking about...Borg Warner P/N 177283....hard to beat at under $1000

Don't overlook the Borg Warner S362 or the S363 (normal or FMW)...they are a fraction of the price of the Garrett options and should perform similarly.

I have the same goal (500bhp, so ~425whp) and will be trying to hit that with my S362 FMW at 16-17psi running 100% water for safety.

A member here just made 456whp at 17psi on a street ported 13B running 50/50 water/meth on a standard S362 with 0.91 A/R turbine housing.

https://www.rx7club.com/single-turbo...7-psi-1032351/

Here is the compressor map of the FMW.

http://www.full-race.com/store/image...-content-1.jpg

BW turbos are challenging to differentiate:

excluding the monster 400 series as well as the EFR line there are 3 that should draw significant interest.

two immediately below are similar to the GT35 as to compressor dimension but have much larger hotsides:

S300SX 8375

S300SX FMW (FMW is billet comp wheel)

S300SX8875 (mid size)

looking at the BW comp maps i have simplified a bit for you.

.........................................14.7 psi................20 psi...............max

S300SX8375......................476............... ......486...................520 (37 psi)

S300SX FMW......................473....................50 5....................550 (42 psi)

S300SX8875.......................452.............. ......520....................570 (35 psi)

the numbers are based on airflow and are approx max. it could very well be that
they may not be attainable given the motor. they are primarily for basis of
comparison.

the turbos come w a slightly funky 4.21 inch backside V band. various vendors can mod it back to the typical 3 inch setup which may be more downpipe friendly.

see Full -Race.com as an example.

howard

I highly recommend Full-Race, especially for BW turbos. They modify the turbine housings for 3" v-band so that the flange is located in the same place relative to the exhaust manifold as Garrett GT turbos, so you can switch without needing to change downpipes.

Howard the most smart purchase is looking towards the turblown unit ( TDX61R ) with the journal bearing option worth 1000us ( 850 euros maybe less )

I will also get a new exhaust manifold and will have to upgrade to an RX7store fuel kit ( fuel rail , fuel reg , 1680s or 2000s ) since my current 1300s are running at 87% with my small T04E

Howard by the way. I thought that my To4E has a T4 flange with 0.84A/R
From what you said both my turbo and cast manifold are T3 Flange????

You also said that at 17 psi it will give 380 max . Is this wheel or motor

I am asking because at 2 different dyno's I saw 408 and 416 bhp engine @ 17psi and my everyday boost is round 20-23 psi on 100 RON fuel ( for the last 5 years...)

Is the AEM water-meth a good option while running the TDX61R ???

Thanks a million

it is probable that your turbo has a T4 hotside.

Innovative offered such a turbo. they generated a compressor map that showed 62 pounds which would be approx 476 max rotary at the wheels if true. while labeled a 60-1, i have my doubts if it is the same comp wheel as the output is much higher than the normal 60-1.

perhaps others can provide further info.

the normal TO4E 60-1 (60 trim) map shows a max of 50 pounds which is 377 rear wheel rotary power. max power at 19 psi, less power at higher boost. using 15% drive-train loss flywheel max (engine) hp would be 443 SAE max from a typical 60-1.

on paper the TDX61 looks attractive, especially against the GTX3582r as it has a 14% larger hotside area. the compressor wheel is not the Garrett GTX wheel so i am very interested to learn more about it.

let's hear from Turblown.

as to water meth w any single turbo setup, especially one in the 500 area... water, or water meth, isn't "good" to have, it is essential. brand-wise, i personally prefer Coolingmist.

howard

The current wheel design is extremely close to the Garrett GTX wheel, just taller. Back to back dyno tests show they are almost identical in power( the unit we use just spools 200rpms faster, as its 1mm smaller inducer). However we have a new wheel design that is in testing, that makes around 3% power MORE than any of the previous designs( including Garretts!). Honestly we've been so busy with so many things that we haven't had the time to really concentrate on the marketing portion of the wheels. We don't have any compressor maps yet( probably be a while too) they are about $15k per wheel, per compressor housing to generate.

We've sent several units out and everyone has been extermely happy with their dyno results, and the " spool " time. Brian @ speed1 just put a similar variant on his car, and told me it was the best turbo setup hes had on it( out of 4+ I believe).

Just had a look at this turbo on the Full race com page

BorgWarner S300SX 8375 Turbo S360

Could you tell me which unit between the above and the TDX61R is more '' streetable'' with less lag???

Anything spooling over 4-4.5K rpm would be too laggy . A 3500rpm to 3800 rpm target boost would be prefered...

The BW unit would have a 0.91 A/R T4 twin scroll and the TDX61R a 1.0 A/R with T4 twin scroll flange

The price of the BW is WAY TOO LOW!!! 800 us only ??? Is the a catch???



Howard one more question. When a turbo says that it produces 50lbs of air what is the max bhp engine for a piston and a rotor engine

I am asking because on my T04E you wrote 46 lbs ... That would mean about 460 bhp @ the flywheel on a piston motor and divide by 1.3 = 346 on a rotor ( is this wheel or engine ??? )

//////// edit and correction from Howard:

while i believe my hp calcs for the rotary from airflow are correct i have referred to the HP estimates published by Borg Warner and Garret as rw. of course they are not. they are flywheel/engine.

so, for instance, a 60 pound turbo rated by Garrett at 600 hp is flywheel power not rear wheel power. using a 15% drive train loss the rwhp would be 510.

this does not change the rotary rwhp calculations from air flow.

60 pounds X 14.471 = 868 CFM / 1.92 = 452 rotary rwhp.

it does change the marginal difference between piston and rotary from a 30% discount to 11%. my apologies ///////////////////////

I am only asking because you wrote :

TO4E 60

46.5 pounds per minute at 14.7 rotary rw 369 hp
50 pounds at 19.4 psi 377 hp

I have seen 415 bhp engine @ 16 psi ( I think mine is a 54 or 57 trim )

If my unit produces 46lbs how can I get 377 wheel = 433 flywheel... since you said that a turbo that produces x amount of power on a piston will only give 2/3 on a rotor ???!!!

What I mean is that a turbo with 46lbs which is good for 450 bhp on a piston should give 346 on a rotor . Unless I have confussed engine and wheel power

What I saw was 415 @ 15% = 350 wheel . Did you mean what my turbo is maxed at 377 wheel @ 19.4 psi

So what power am I doing at 22psi ...??? Probably much less

////////// first off, i suggest you forget about the piston rotary relationship and concentrate on your situation. i realize i contributed to your confusion by not using flywheel hp. moving on...

415 fw hp. X .85 = 353 rwhp. it takes 46 pounds per minute. the turbo makes 46.5 pounds at one pressure ratio. it makes a small additional amount w increased boost.
do keep in mind that a turbo must be driven rightward on the compressor map to produce maximum flow. you can be at 16 psi and 40 pounds of flow or 46 pounds.///////

If my goal is 420 wheel BHP why doesnt anybody recommend this one as well

BorgWarner S200SX 7670 Turbo . Claims 380-500 wbhp with a standard T4 twinscroll 1.0A/R or 0.84 A/R ( my current A/R is also 0.84 on the T04E )

Why do we need something bigger like the BorgWarner S300SX 8375 Turbo S360 which is recommended for 500wbhp +++

Bear in mind that my goal is a healthy 400-420 bhp wheel and still a very drivable - streetable FD

"Could you tell me which unit between the above( S300SX8375) and the TDX61R is more '' streetable'' with less lag???

no

i can give you some comparatives which might help.

compressor (cold) side

S300SX 8375 compressor area 6.437 square inches (average inducer & exducer)

TDX61 compressor area 6.443 (GTX35 less 1 mm/inducer)

GTX3582r compressor area 6.518

GT3582r comp area 6.386

all close but the TDX and GTX are billet. billet wheels are made from stronger material and as such they feature smaller hubs and therefore deliver more working (vane length) area and deflect less at very high boost. in this case area is not linear w output.

turbine (hot side) area

S300SX 8375 turbine area 6.31 sq inches

TDX61 turbine area 5.89 sq inches

GTX3582 5.17 sq inches

GT3582r 5.17 sq inches

ratio hot to cold

S300SX8375 98%

TDX61 91%

GTX3582r 79%

GT3582r 81%

face it, turbos are designed for piston engines. rotaries are different. they require more flow to make the same power and 3 to 400 additional degrees of EGT. it is no accident that Turblown grafted a much larger hot wheel on his TDX... the weak point in the GTX35 (may) be the small hot side wheel.

i would not worry about lag. my mid size BW hits full boost very close to 4000. each of these turbos will do fine mid-range. BTW, there are way many more factors that influence spool. check your EGTs between zero boost and full boost. i will bet they are around 1100. tune for closer to 1400. tuning midrange is often overlooked for the top tick number.

as to output V power...

46 pounds will produce (approx) 391 rwhp on a piston engine and 354 rotary.

there are two ways to ESTIMATE rwhp for the rotary. both are empirically derived and they both work well.

pounds per minute X 10 / 1.3

46 X 10 = 460 / 1.3 = 354

pounds per minute converted to CFM / 1.92

46 X 14.471 = 666 CFM / 1.92 = 347

just like dynos there is always some wiggle but they work pretty well.

you did 416 flywheel/engine at 16 psi

416 is approx 354 at the wheels

46.5 pounds at one pressure ratio (14.7) works out to 350 rwhp

you made 354 at a slightly higher boost. all the estimates are maximum.

close enough.

looking at the compressor maps for the 60-1 and other TO4Es nearby generally above 19 psi you will lose power.

howard

"If my goal is 420 wheel BHP why doesnt anybody recommend this one as well

BorgWarner S200SX 7670 Turbo . Claims 380-500 fwbhp with a standard T4 twinscroll 1.0A/R or 0.84 A/R ( my current A/R is also 0.84 on the T04E )

Why do we need something bigger like the BorgWarner S300SX 8375 Turbo S360 which is recommended for 500wbhp +++

Bear in mind that my goal is a healthy 400-420 bhp wheel and still a very drivable - streetable FD"

simple.... it is too small for the rotary and your power objectives. due to it's size, it's max flow will produce just at 400 at 20 psi boost and it is right at stall.

again, the 500 is fw piston... 425 rw piston

500/ 1.3 is 385 rotary which is very close to max. you do not want to run a turbo that is maxxed at your power objective.

hc

I'm running a BW EFR7670, and I don't want to ever switch back to anything else again. My first single was a weird hybrid that I bought from an MR2 guy with a turbine housing that was WAY too small. Didn't know any better at the time. Then I got a 500R-SP and it was good, but still didn't spool quite fast enough for me. At the time I was mesmerized by the numbers and the name of the turbo rather than going for what I was looking for, which was fast spool. I'm in love with my current turbo. Starts spooling around 2500rpm and pulls nice and smooth for the most part, and what I mean is I have to take it easy through the first 3 gears or I'll just spin. I haven't had it on the dyno yet and I'm not sure yet if I will. I think I'm only making around 360whp at 6000ft altitude, and something like 450whp or so at sea level (if I reworked the tuning a bit, because oddly enough if feels a bit slower at sea level and it's running richer, which really throws me for a loop because I figured it would run leaner). I could probably optimize by messing with the tune and tuning up on the water injection too, but honestly I'm super happy with the power and response right now. I'll spin all the way through 3rd gear if I just stomp on the pedal. In 5th gear at about 55mph and around 3000rpm I don't even have to downshift to go around someone, I just push down and go. I LOVE it.

Dear Howard

The turbo that speedjunkie wrote is very interesting...BorgWarner EFR 7670 Turbo

From their page it has a 64lb/min compressor flow which from your math is 640 bhp wheel on a piston or 492 wheel rotor power

So from these maths the 400 whp @ 20psi sounds a bit weird since it can give 492whp according to your math

I have also found out that the power figures in real life are very different than the figures on maps and maths...


I would like to add a comment from my experience....Are you 100% sure that the figures on the comp maps in lbs translate in whp. Why do I think that value ( from maps or bhp rates made by the turbo designer ) are always bhp @ the engine

As you know the true power is torque which the dyno can convert to either bhp @ the engine or the wheel

So how can a turbo manuf claim a bhp figure @ the wheels since it doesnt know either what car it will go on... or if it is front - rear or 4x4

For example. We used a Garrett 2876 on a 2lt piston engine. The engine had eveything...Racing crank , forged pistons and rods , big inlet and exhaust cams , AEM ecu the lot

If you see the compressor map it will give 50lbs @ 1.5 bar or 22psi. This is 500 whp from your math.

This car run at 25 psi spike coming back to 22 psi and produced 430 bhp engine which is roughly 350 whp since the car was a 4x4 ( 20% drive line loss )

As you can see there is a MASSIVE 150whp between the map ans real life at the exact same psi

Second example on a rotor... My dear friend and tuner used a GT4088R on his street port RX7. If you visit the Garrett website you will see that the map wields roughly 68 pounds @ 19 psi

Ok so at 19psi that would give 680 WBHP on a pistor or 523 wbhp on a rotor. With 15%-17% drive line loss that would be about 600 to 610 bhp engine. My friend achieved 565 bhp at the engine @ 22 psi and 590 engine @ 24 psi . That is 474whp and 495 whp

So lets sum it up

GARRETT figure for the GT4088R

19 psi 68lbs good for 523whp on a rotor

Actual real life date

22psi 474whp or 565 crank
24psi 495whp or 590 crank

Of course the figures of the FD engine are not massivly out since we had to use 3psi more and achive 50whp less. At 5 psi mpore we where 28whp out but still @ 5psi MORE than the map

The figures on the 2lt piston engine thought where 150whp out

If on the other hand the Garrett map was for 50lbs and actually 500bhp @ engine then the figure we got was still out but by only 70bhp engine and not 180bhp engine ( 150whp )

Again coming back to my engine. The garrett map on my small unit claims 350-370 max at the wheels and I have already seen 350 wheels @ 15 psi but have not dynowed the car beyond that. I know for a fact that it feels stronger @ 19 or 20 psi so the 370 figure whp is not a lie.

Again another example that maybe uor engine will ACTUALLY PRODUCE what the Turbo manufacturer claims...Pistons are a waste of time , money and effort LOL

Example 3 regarding the FD using the BW 8875 @ 17 psi

The map shows @ 1.15 bar roughlt 68 lbs or 0.5 - 0.52 kg/s . That would be 680 whp ////s/b 680 fw hp///////on a piston or 523 whp on a rotor

Our friend achieced 458whp with water-meth which is 65whp or 75bhp engine of the map//////the 523 number is the maximum. your friend did not reach the far right flow area of the map at that boost level//////////////////////////

If the map was on engine power and not wheel power as you said then the power figure would be almost bang on . ie

523 bhp engine according to the map @ 17psi
Our friend achieved 458whp = 530 engine power

So he is 100%!!!! bang on the map ( 523 claimed - 530 achieved )

So my statement regarding maps and figures on engine power and not wheel horse power is not far off!!!

After doing the math on your comment regarding the BorgWarner EFR 7670 Turbo please follow my way of thinking...

You said that this unit will only produce 400 whp @ 20 psi ...This means about 470 engine

The map shows 68lbs. Say for example that I am correct and all these figures give bhp at the engine and NOT at the wheels

So 68lbs = 640 bhp engine piston = 492 rotor engine piston = 405 wheel horse power rotor

So the 400whp you claim for the BorgWarner EFR 7670 Turbo is BANG ON the actual theoritical figures produced by the turbo math but ONLY AND ONLY IF the figures we derive are BHP at the engine ( as I thought ) and NOT at the wheels

This is explained by 3 different examples on 3 different FD engines and only by assuming that the lbs written on the maps make engine bhp and NOT wheel bhp. As you saw the actual figures produced in real life on dynos where also close to 90-95 % to the bhp claimed by the map but with engine bhp figures and not wheels

What are your thought and comments???