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Ziggy Socky!
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Discussion Starter · #1 ·
I have a question for matt or any other member. I want to stay on the safe side running 15-17 psi on my turbos, no alcohol or propane injection, daily driver. Will Dr500 turbos have a better 1/4 mile time vs. 650's only running this psi because of less lag or will the 650's dominate in the long end.

I want to go with 650's because I don't want to regret getting the 500's and need to spend another $1200 on a turbo swap.

Is there anyone to convince me the 500's are better, I will be using a 550 injector setup with s-afc + BPU, posible arc2 if I can buy it cheap?

Any arquements will be gladly considered.
 

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Here's the deal...if you shift at the right points your RPMs should never drop below 4600rpm while running the 1/4. So you're shooting for 15-17psi right? Well as long as your turbos are not too large to make 15-17 psi by 4600rpm you probably won't loose any ET or MPH due to lag.

Lag is WAY overrated for 1/4 mile racing...you would need to switch to a damn big turbo to actually slow down (providing you keep the revs high and shift quickly to keep the turbos hummin'). I don't think anyones hit that point yet with our cars.

Now too big to daily drive on the street in traffic where it's not annoying...that's a whole 'nother ball of wax.
 

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Ziggy Socky!
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Discussion Starter · #6 ·
Thanks for the help trevor. Why then are you opting to go with the 16g vs. the 18g if lag is not so important? Perhaps those are the "Damn big" turbos you were reffering to.

As for the daily street driving are the 650's notably annoying? When I called Dynamic Racing the guy who answered the phone (Not Matt) said the 650's only require 500 more rpm's to reach my 15-17 psi. Can anyone who has experienced both sets give me their impressions.
 

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If all I cared about was 1/4 times I would run 18G's (maybe even 20G's). The reason I opted for 16G's is I care about how resposive the car is around town since I use my Stealth to go back and forth to work as my daily driver. Hell...I'm even annoyed by my wife's Z's lag...that things worse than my Stealth!

It's not like 16G's are small or something...the compressor is physically the same size and trim as a 368 which are even bigger than the 650's you're talking about.

I haven't driven a 650 car but I can't see lag as being much of a problem with them at all. That 500 rpm estimate sounds about right. Matt and other 650 owners say they spool really quickly.
 

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Ziggy Socky!
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Discussion Starter · #8 ·
Great. You've told me exactly what I wanted to hear. I believe I will be getting the 650's when I have a little more time and money.

I hope everything goes well with your TDO5 setup. With your weight savings and experience you should have a hell of a fast car. By the way do you know how your car weight compares to that of Mahaffey's?
 

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macg23: I'm in nearly the same position as you for deciding between the 500s and 650s. I asked Matt almost the same question. I want to run 18 psi at most with my new turbos w/ 550 cc injectors. Matt said that the DR500s would be better for street use than the DR650s if I planned on not boosting over 20 psi. He also said that the DR650s don't have a lot of lag for a large turbo. The DR500s seem to be a capable turbo if they can pull away from a viper on a roll w/ our cars drivetrain loss and weight.
 

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Ziggy Socky!
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Discussion Starter · #10 ·
VR4GUY I have heard this before too. I am in no way degrading the dr500 turbos but why would a person not purchase the 650's if the lag is so close between the two. I understand there is a $600 price difference but with all the money spent on preping the car in the first place it seems almost obtuse to not buy that extra performance.

Is there posibly another reason, do the 500's have better wear life on the street with stop and go driving? Is there any lifetime difference between the two?
 

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I doubt there would be much of a difference in life, maybe the DR650s would last longer since they need to work less to flow the same as a smaller turbo?

I forgot to mention Matt said that I would need a bigger mass airflow sensor (ARC II) or a vpc to get the performance out of the dr650s

If you decide to go with the 650s tell me how they work out and how the lag is compared to stock.
 

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Lag is, or can be, very important if you do
a lot of commuting around town. That 500
rpm spool difference will seem very big when
you go to shoot around another car without
a downshift. The stock 9b's have "right now"
power that makes these cars the grin inducing
machines they are. I had my Supra set up in
"true twin" mode. They would spool hard at
3800 rpm or above. I hated having that much
lag but liked the boost curve much better than
sequential so I learned to drive around the lag
by choosing the correct gear. The 15g cars I have
driven have been slightly laggier than the Supra
and the DR650 has a little more lag than a 15g.
If the rush of a strong highway pull from 60
to 160 is what you are after,then go with the DR650's.
But if you are only going to run 18 lbs boost the
DR500's will give you most of the performance and
be more fun to drive on a regular basis.
JMHO,
Wayne
 

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Ziggy Socky!
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Discussion Starter · #13 ·
You have some very good points Wayne.

I guess what is comes down to is just personal preference. I suppose I will never truly be able to justify my choice without personally experiencing both setups. I need to go to a few of the gatherings and ask for some rides.

With that does anyone close to the evansville area have either turbo on their car? I would sure love a ride. :burnout:
 

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Here is a story for you I recently had 357 replicas in my vr4. I could hit 15psi around 4000rpms as compared to 2500rpms with my 9b's needless to say I was very disapointed. It change d the whole driving style of the car for the worse. I could no longer get that rush I was feeling before when I floored instead it seemed like forever before the power would come. I would always run higher in the rpm range to keep the car in the powerband. I was so dissapointed that I took the turbos out purchased my 13c's basically same as a dr500. I am very pleased with these turbos they hit hard especially in this cold wheather I can hit 16psi by 2900-3000rpms now that the air is colder and about 13.5psi at 3000rpms in the summer. But I agree it's all what you want the 357 replicas pulled much harder once the hit but I could not get over the extra lag.
 

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Unless you plan on having a track based vehicle ... get DR500's. I have the 650's and I love them ... but I am at the dragstrip 2-3 times/month and next year will be road racing every weekend. The bottom line is ... to truly appreciate bigger turbos like 650's or TD05 anything ... you need to DRIVE THE FUCK out of the car. You need to stay in annoyingly high RPMS and you have nothing off the line unless you rev up to 6k and dump the clutch ... something I am NOT comfortable doing at every stop light. Basically if you are going to strap race turbos onto your car ... be prepared to drive a race car. I have to admit ... I do miss being able to drive my car all the time ... now I only drive it when I want to go racing because I might as well be driving a volvo if I'm nopt keeping those turbos in their powerband.

To answer your question I think the DR500's are phenominal street turbo's and I recommend them as a must-have upgrade for any VR4. They are the kind of turbos a touring car should have. You can solidly make 4-500HP out of them. I'd recommend DR650's for someone who wants a serious street car that can also flourish at the track. I'd recommend TD05 anything for people that like driving their car to the track on a trailer. Maybe the 14b's or 16g's for a street car ... but even then I bet the lag would be pretty stupid.

And the DR650's hit hard between 3300-4000rpms. I'd say I make good boost by 3500 in 3rd.

Oh and getting DR650's (or larger) without a freer flowing MAF and a catless exhaust is kind of wasting your money.
 

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Thanks for the posts you guys with the larger turbos. It re-affirms my decision to just keep my TEC 15G's, which hit ~16 psi by 3000 RPM in 2nd or 3rd gear roll-on from ~1500 RPM. I never wanted the ultimate drag car, just something that would not be embarrased by the lastest big-buck BMW. :) If I can get my drag times to around 12 s I will be very happy.

For you guys considering 13G/DR500, my friend Dean's car, a '94 VR4 with 13G turbos and similar mods as mine, definitely pulls harder from a roll-on than my car does. But the very top-end suffers.
 

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Ziggy Socky!
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Discussion Starter · #18 ·
Crap, Crap Crap Crap.

I thought I had my mind made up. Why did such educated people have to answer my post? I suppose I wanted to justify the 650's in that some day this will not be my daily driver and I could only take it out on the weekends.

All in all you guys are probably right. I didn't want to admit it but I normally shift around 2k. I thought the larger turbos would inspire me to be a more aggresive driver. The last thing I want though is to spend my money and become less satisfied.

I appreciate everyones help on this topic and any more opinions here would be greatly accepted.:thumbsup:
 

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I'm with Jeff on the 15G issue. They're a NICE daily driver turbo. 15psi by 2900 rpm for me (lower altitude and very open exhaust)...damn thing drives like a V-8 around town.

Of course when I'm at the track I wish my back pressure was lower, my EGT's were lower, and I could find some more top end. Such are the trade offs.


I can't wait to get my 16G's...I bet their 15psi by XXXX rpm is going to surprise some people. I hope it won't be a bad surprise though...

"What! It doesn't spool until 5400?!?!" :eek: :p :D
 

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Trevor said:
I'm with Jeff on the 15G issue. They're a NICE daily driver turbo. 15psi by 2900 rpm for me (lower altitude and very open exhaust)...damn thing drives like a V-8 around town.

Of course when I'm at the track I wish my back pressure was lower, my EGT's were lower, and I could find some more top end. Such are the trade offs.


I can't wait to get my 16G's...I bet their 15psi by XXXX rpm is going to surprise some people. I hope it won't be a bad surprise though...

"What! It doesn't spool until 5400?!?!" :eek: :p :D
Well you know the compromise you can do is always go with a split turbo configuration. Right now this second (and for the last 5 weeks) my VR4 has had only 1 DR650 and 1 9b. That has gotten me a [email protected] with a great launch. Granted once I get the other 650 fixed it is going back on and I will be sniffing 11.5's ... but still not bad. I am doing this with the stealth. Since it is my own project lo-buck ... I am thinking either one 15G or 17G and leave on 9b. This mitigates lag nicely but also gives some nice high-end punch. You get positive boost as low as the 9b will pump it (1800 rpms for me with no cats) and then once the second turbo kicks in full force you get all the power you want. In the high end as the 9b starts to lag off the other turbo spins even faster to make up for it. With one DR650 and on 9b I can start making boost at 1800 rpms ... really get a kick in the ass around 2500-2700 rpms ... and hold 15-16psi to redline. Not bad at all. I imagine a 17g/9b combo would produce similar results.
 
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