Jump to content
The mkiv Supra Owners Club

Comparison of Single Turbo RWHPs


Jake

Recommended Posts

Looking at my old T67 journal bearing graph it sits between Jakes and Gamers. Nice :)

 

4000rpm = 215bhp

5000rpm = 420bhp

6000rpm = 570bhp

6500rpm = 630bhp

 

Factor in my 8% drivetrain losses

 

4000rpm = 195bhp (just ahead of Gamer)

5000rpm = 385bhp (just behind Jake!)

6000rpm = 525bhp (equalling Suprafan)

6500rpm = 580bhp (er, hang on... :blink: )

 

Wait a minute, much as I'd like to think it were true, the old non-Dbb T67 surely can't leave a T71GTQ for dead and then overtake a T51R? Apart from Jakes turbo massively pwning the others below 4500-5000rpm, it appears to be the best of both worlds - faster spool and more power. What was the boost these turbos were running at? What cams? (cams are a huge factor in 6000+ rpm breathing, stockers really choke up)

 

One day I might get the DBB dyno'd but I'm not sure I can be arsed as I know it's 'better' in the midrange :)

 

-Ian

 

Mine was running at a measly 1.4 Bar.... 8 per cent drive train losse's mmm... I'd be interested Ian in taking mine to the same dyno as you had your old T67 dynoed at... and im using 272/272 cams with ported and polished heads, oversized valve etc.

Link to comment
Share on other sites

  • Replies 102
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Posted Images

In my mind those opens up a whole debate on what dyno is right (if any) and what dyno's are wrong... Really when looking at these figures they could mean anything and in some cases totally wrong..

 

I guess as Chris W said the only way to tell would be to taken the engine out and put it on an engine dyno.

Link to comment
Share on other sites

Interesting stuff.

 

What has also not been mentioned is the fact that the samall 35's have almost an instant throttle response. At 4k, you get instant power, whereas the bigger tubbies still take .5 or 1sec to power up at high revs.

 

If you took a big tubby on a racetrack you would be completely screwed.. they are ok on the road, but my car, as it is now, would be a total waste of time on a track.

 

This is something dyno's don't show, but a really important part of driving in twisties.

 

Don't get me wrong, on the open road the medium and big singles are devastating, but useless, if not very dangerous, on the open winding roads.

Link to comment
Share on other sites

Interesting stuff.

 

What has also not been mentioned is the fact that the samall 35's have almost an instant throttle response. At 4k, you get instant power, whereas the bigger tubbies still take .5 or 1sec to power up at high revs.

 

If you took a big tubby on a racetrack you would be completely screwed.. they are ok on the road, but my car, as it is now, would be a total waste of time on a track.

 

This is something dyno's don't show, but a really important part of driving in twisties.

 

Don't get me wrong, on the open road the medium and big singles are devastating, but useless, if not very dangerous, on the open winding roads.

 

Agree with you there mike... and on a track a sorted Bpu or small single would be all over the medim to big single guys.. hence why im not really interested in the track or drag racing really....

Link to comment
Share on other sites

Interesting stuff.

 

What has also not been mentioned is the fact that the samall 35's have almost an instant throttle response. At 4k, you get instant power, whereas the bigger tubbies still take .5 or 1sec to power up at high revs.

 

If you took a big tubby on a racetrack you would be completely screwed.. they are ok on the road, but my car, as it is now, would be a total waste of time on a track.

 

This is something dyno's don't show, but a really important part of driving in twisties.

 

Don't get me wrong, on the open road the medium and big singles are devastating, but useless, if not very dangerous, on the open winding roads.

:goodpost:

Link to comment
Share on other sites

I have been thinking of moving to the GT4088 or T51 as my car is in pieces and I have a new engine going in, I have spoken at length with a couple of people and decided for now to put the old T04R back on, I will be very interested to see the power delivery change from this turbo with the new engine as the old engine was stock apart from the exhaust cam (264)

The new engine has uprated Rods, Head bolts, valves, valve springs and retainers, 272 cams on exhaust and inlet and polished head, I will post both graphs when this work is complete at the end of August :)

Link to comment
Share on other sites

Hello guys,

Interesting thread. I have a hks To4r .96 and stock cams. I dont find it laggy and like someone said earlier in a manual you can just use the box to get the car going.

Also i believe the driver makes a big difference to how the car performs on road. I am well happy with my to4r and find that my car actually grips alot better than when i had my twins, because it really squats when the boost kicks in.

Link to comment
Share on other sites

Hello guys,

Interesting thread. I have a hks To4r .96 and stock cams. I dont find it laggy and like someone said earlier in a manual you can just use the box to get the car going.

Also i believe the driver makes a big difference to how the car performs on road. I am well happy with my to4r and find that my car actually grips alot better than when i had my twins, because it really squats when the boost kicks in.

 

I also have a T04R with an auto, the power comes in noticably at 4K and full at 4200, in auto mode there is a little lag but you can compensate with MANU mode, i am going to test it against my mate's auto GT3568R for comparison.

Link to comment
Share on other sites

I also have a T04R with an auto, the power comes in noticably at 4K and full at 4200, in auto mode there is a little lag but you can compensate with MANU mode, i am going to test it against my mate's auto GT3568R for comparison.

 

Wait till we have had a play with it matt:)

Link to comment
Share on other sites

Well mine put down 455 bhp at the hubs at JAE on thors hub dyno and 458 at the crank calculated using transmission run down on the dyno at my tuners the day after. Obviously a bit of a difference. My tuner basically told me that my T61 was only realistically good for about 500 horses total and that mine was still being kept safe and a tad rich :)

Link to comment
Share on other sites

*Shameless plug* :D

 

We have a RR day booked on Aug 25th at SRR (i.e realistic rw figures). So far there are two same spec 6spd single supra's going:

 

DAF GT4088

BL T67DBB

 

Would be great if any of you 6spd single supra owners (Jake, Suprafan, etc) can make it along to do a back to back comparison at 1.4bar

Link to comment
Share on other sites

I also have a T04R with an auto, the power comes in noticably at 4K and full at 4200, in auto mode there is a little lag but you can compensate with MANU mode, i am going to test it against my mate's auto GT3568R for comparison.

 

The trouble is though; say you come round a corner at 5k, you are ready to feed power in up the straight..

With a smaller turbo you can get pretty good throttle response, so you can feed in throttle effectively and get a grippy slingshot out of the corner... because you have a direct relationship you can tease the back end's grip and get an accurate balance between power and traction.

Come out of the corner with a bigger single and the inertial lag of the turbo spinning up is so much more that even at 5k the throttle response is extremely slow by comparison... so in reality(unless you are really talented or insane and lucky) you just can't get out of the corner with any accuracy. Even if you are given 2 clear gears of boost I recon you would be no quicker being 150 hp up on a smaller single.

 

I am horrified at just how bad the 4088r is for driving around the twisties... I tried it tonight, the dyno prints are not so different but in real life the car is a totally different beast, even if you keep the revs above 5k, just not a smooth car to drive.

Link to comment
Share on other sites

How do you mean "Factor in my 8% drivetrain losses"? It works the other doesnt it? The 580rwhp was what was measured and the 630fwhp was calculated, wasnt it?

 

 

8% of 630 is 50. 630-50 = the 580 they measured at the road, ergo, 8% of crank power lost through drivetrain. Therefore, drivetrain loss :)

 

I see this has turned into another "BPU is faster than a single turbo under all circumstances" thread ;)

 

-Ian

Link to comment
Share on other sites

I am horrified at just how bad the 4088r is for driving around the twisties... I tried it tonight, the dyno prints are not so different but in real life the car is a totally different beast, even if you keep the revs above 5k, just not a smooth car to drive.

 

This I'm really surprised at Mike. Mine has a supposedly similar spec turbo, but the lag time and smoothness when hitting the throttle at 4k rpm is virtually instant - just a fraction of a second to go from deceleration to 1.2bar+ boost.

 

Are you able to record any video of this? I can try the same (if I can get the damn camera setup properly!)

 

Had mine round some nice A and B road twisties this weekend (200 miles worth) out in the west country and it was just incredible. The power and low/mid range torque is just awesome. Barely even went above 6k rpm, it's just not needed.

Link to comment
Share on other sites

Feck i forgot about that site Darryl lol

what about the number crunching part though as in that link, would be interesting for making comparisons, should be enough Dyno graphs around to get some starting data

 

I'm working on something, but it's going to take a lot more input from folks here :D

 

Will be posting more in a months time.

Link to comment
Share on other sites

You'd have to agree everyone uses the same dyno or atleast the same kind of dyno hardware & software.

 

Yes, thats the idea Gaz (along with recording AIT, humidity, etc) so losses/gains can be approximated to some degree.

 

It's a long way from an exact science but will at least allowed for some reasonably close approximated figures at the same RR.

 

As mentioned, if anyone is interested, try and get yourself along to the RR day ;)

Link to comment
Share on other sites

This I'm really surprised at Mike. Mine has a supposedly similar spec turbo, but the lag time and smoothness when hitting the throttle at 4k rpm is virtually instant - just a fraction of a second to go from deceleration to 1.2bar+ boost.

 

Are you able to record any video of this? I can try the same (if I can get the damn camera setup properly!)

 

Had mine round some nice A and B road twisties this weekend (200 miles worth) out in the west country and it was just incredible. The power and low/mid range torque is just awesome. Barely even went above 6k rpm, it's just not needed.

 

I do need to buy a video camara, and yes, the difference is huge... if you have instant throttle respons I would like to know why or how so I can replicate it!

 

I would say the GT35R is virtually instant, although it's been a while since I drove a TVR or something asperated that is similarly powerful, so maybe not instant, but the differance between these two tubbies on throttle response is huge.

 

It is a divided housing .96 ar, this 4088, whereas the 35 I have is '68. maybe that would have some bearing compared to yours.. what 'ar are you running?

 

The turbo is brand new and free flowing; you can hear the thing spin for a minute after the engine is turned off.

 

I would like the power of the 4088 in a turbo that had the throttle response of the 35, I can live with a powerband 5/600 hundered rpm further up the scale. If I could quantify your setup I would go and buy your exact turbo in a heartbeat...

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.