Solid 9 Second turbo?

[no-nos]

as an owner of a 70GTQ DUAL BB, i wanted to build my car as a high 9's car that can still be street driven and a 70GTQ Dual BB i can honsetly say it has great street manors and spools up almost instantly, i do have a 9" non-lock-up at 3200. a 76-turbo will have a lot of lag, remember you said street driven.
trust me you'll have more than enough power from it, I'm not as experienced as some of these guys are, trust me i asked guys here also before i purchased mine, the 70gtq dual bb spools up great.

I say this turbo is definetly a part of the big picture, but you gotta have all the other parts line'd up in order to get a 9' sec pass. I know you have a roller cam, rockers, iron heads (ported i take ) but do you have the right injectors? remember fuel delivery twin in tank fuel pumps, headers and so on. what you want is kinda like what i wanted, but truth be told i may see the track maybe 3-4 times a yr. ( how about you ?) the guys have given alot of good advice but i guess it comes down to how much have you got to spend ( cause a new turbo is expensive ). good luck the purchase :smile:

ohh btw here's a pic of my 70gtq

 

[karolko]

i have been working very hard to lighten up the car. i have no idea what i weighs currently though.

I have will have 83lbs injectors, champion gn1 intake, larger throttle body, 3.5 dp, fast xfi, all the goodies to make her go, it is just a matter of the right tune (by Cal of course)

no-nos, i noticed that you have a 3200 non lock up converter and you say it spools up almost instantly. how might a non lock up differ from a lock up with regards to spool time?

bison, i guess i am partially to blame, i would like a car that can hit the nine second mark, 9.99 would be okay for me, for now that is.

i am enjoying learning what others have to say about this. it just makes me think more and more.

 

[karolko]

Here is another idea. how about the pt 6780 turbo. this thing should, and correct me if i am wrong, a .67 trim exhaust wheel and a 80 trim compressor with a 0.85 A/R. similar compressor trim, but witha .67 trim to keep the thing snappy on the street.

 

[oldtimer]

The thread is called "solid 9 sec turbo". Most realize theres a lot more to a 9 sec et than a turbo. We have already touched on a few of the things you mentioned. Tuning seems to be the one step most miss.

Yup, and I respectfully agree. I was looking beyond Adrian's title on the thread, at his "goal" of achieving a 9 second pass, and this is what I was responding to.

 

[bison]

Here is another idea. how about the pt 6780 turbo. this thing should, and correct me if i am wrong, a .67 trim exhaust wheel and a 80 trim compressor with a 0.85 A/R. similar compressor trim, but witha .67 trim to keep the thing snappy on the street.

Thats a 67 comp and an 80 trim ex? Whats an 80 trim. Maybe an HPQ?

 

[kingots2004]

you could use a small shot of nitrous to spool and keep a tighter converter for street use.so you could run a big turbo and tight converter alot of turbo guys do it

 

[TURBO 6]

The DBB 6776 has been 9's at 140 mph. JC's GN did it on pump gas and alky. Do a search. I've been pm'ing him for two weeks verifying that I can duplicate the 140mph. Going to the track in two weeks.

 

[SS_Sean]

I've been following this thread with great interest. It's interesting that the majority of responses are talking about turbo size and construction and although very important, there's much more to running a 9 second timeslip than a bigger turbo. My experience tells me that most average turbo racers aren't seeing the maximum that their existing turbo (whatever size ) can deliver !

Adrian is wanting to run a 9 second pass, he hasn't ever mentioned he wants to MPH in the stratosphere.

Suspension, converter, gearing, weight of the vehicle, boost CONTROL, driver experience and most of all, the right tune (not song) all have a major role in lowered et's.

The highest MPH and/or the fastest car doesn't always win the race.:wink: A good 60ft will lower et considerably !


Just another way of looking at this goal of Adrians.

I assumed this was an 'all things being held equal' conversation. He asked about turbo's, therefore I assumed all else would be held equal. If we want to discuss 9 second combo's I think that's another thread, and not what he was looking for. Correct me if I'm wrong.

 

[karolko]

correct. i want to know about 9 second capable turbo's.

Turbo 6 who is this mystery man. i have searched for a while now but haven't found anything.

do you know his combo??

 

[TURBO 6]

alky forum sticky "fastest alky car" read away.

 

[bison]

He is looking for a solid 9 sec turbo. His application looks more street oriented than a race car. Which means he has no rules to abide by as far as turbo size. The TSM guys go really fast on a 70 or 71 GTQ. This is not the turbo they would be running if the rules were different. It certainly is not anything with a 76 trim exhaust either. A solid 9 sec. turbo at his altitude would be a 76 with an HPQ exhaust wheel or a slightly smaller comp wheel in a 4 bolt configuration. Notice i said solid 9 sec (like the title of the thread. Which means not overworking the turbo to get the job done. Not just a couple 9 sec slips on good passes when the stars align. I mean solid. Which is repeatable day after day on different tracks and ambient temps. The 6776 is a great street turbo for 3600 lb cars wanting to run 128-130mph in the quarter with the correct mix of parts. Its not even close to a solid 9 second turbo. More like a solid 10.50-11.00 turbo. A GTQ or better exhaust wheel is needed.

 

[TURBO 6]

Bison, I agree. If I wanted a solid 9 second turbo I'd go with a 76.

 

[RUQWKNF]

Just for the record,

6780 = 67mm compressor wheel, 80 trim GT-Q turbine wheel.
This turbo is good for maybe 800-825 flywheel hp maxed out.
In PTE speak, this turbo would be available with 4 different compressor cover options. E cover, S cover, H cover and HP cover. HP = H cover with ported shroud option. It was also available in both journal bearing and dual ball bearing form. I'm not sure if they have their new compressor covers available yet for this turbo, you'd have to verify with them.

With your goals and ellevation, I still stand by my original recommendation of 74-76mm compressor wheel and either a GT-Q or HPQ turbine wheel for solid, repeatable 9 second capability. This could be achieved without having to max out the turbo. I highly recommend the dual ball bearing CHRA as well, to maintain streetability with a 235 CI motor.
Lot's of good info in this post.

Later


Patrick

 

[matt87]

Adrian, just to clear up some info for you, the torque converter is a precision industries vigilante 3200 stall single disc l/u. also i weighed the car when i made that 10 sec pass and it was 3500 lbs with my 200 lbs self in the car. so figure it weighs 3300 with a half tank of gas. the car 60 ftd a best of a 1.43 off the foot brake so i know it hooks just fine. please do yourself a favor and call Jack Cotton, he built the car and knows it better than anyone here( no offense to anyone) and see what he thinks.

 

[karolko]

Hey Matt, thanks for clearing up the converter for me. i was under the assumption that it came with the transmission.

For you guys recommending the 74-76 turbo, how much larger, or more umph does this this have compared to the 70gtq?

the only reason i am hesitant about these larger turbos is that i know i will be dropping the boost for the street, just promote engine longevity, and when doing that, i am afraid that the car/turbo will feel a little sluggish in around 20lbs, compared to a 25-28lbs (when racing)

am i on crack when i say this, i have had a long day of fighting the bugs waiting for the helicopter today..

Yes lots of great info here. thanks to all of you guys

 

[Dusty Bradford]

I'd get with Jason Cramer if I were in this situation. He races at altitude with a 70mm in a full weight street car and can put you in the right direction with his experience doing just what you need info on.

What Patrick said is correct. You may need a 74mm or so but it's best to try and stay with as small a turbo as you can. And you can forget running 9's at altitude with 25-28# of boost with iron heads. Maybe 35-38....