Turbo or convertor - which to buy?

[gaminoree]

Rob, not to change the subject but can you give me a low down on how to change out the wheel cylinders to s-10's. I just bought some and need a step by step list on how to do it. Thanks a bunch..... tgamino@yahoo.com

 

[XLR8]

A stock TC with a stock turbo should build boost quick - it even does so up here at 5800'. 1. Change your fuel filter. 2. Turn FP down to 43#. 3. Lower boost to 16#. 4. Check your headers for leaks and get them repaired. 5. Check to make sure yout converter is stamped D5 D5 D5 all around. 6. Make a test run - the car should spool instantly. 7. If you get KR - lift and either lower boost or raise octane.

 

[rob86gn]

I've got a 255gph Wallbro hot wired. It's only a few months old. I was told by Precision that it would be enough to run with the 42.5lb inj and the stock turbo. The engine doesn't cut out or pop at all, only detonation that I can't feel or hear, which makes me think it's not enough octane (93 when I recorded the data-104/93 mix when I ran 14.45) for 20psi. Is anyone else running 93oct at 20psi? If so what is timing set at? Mine was 20 degrees.

Also, I do not have a D5 converter. I think this one goes in a van or somthing. It came with the car. I'm ordering one from TCS, 2400stall 12" l/u for $200 plus shipping.

 

[Robert Walton]

I'm ordering one from TCS, 2400stall 12" l/u for $200 plus shipping.

Look in the Vendors section for Century Automotive in Houston. Mike Kurtz is the man when it comes to turbo transmissions. I bought a restalled D5 from him for around $280. Stalls at 2800 rpm. Love it.

 

[GNVYUS 1]

Sometimes guys cheap out and put in the converter from a Cutlass etc, sounds like you got one of those in there. I got one of those in a 200 I bought off a local.

If you are trying to go faster, a 12" 2400 stall is not going to give you a hard on. And saying D5 and fast in the same sentence is pretty laughable.

If you are going to spend $200, then get a Pats 10" 3000 on sale for around $400 and really wake that car up.

20 degrees and 20psi on 93 octane is a suicide run. Drop the boost to 15psi and start tuning from there with 0 knock in mind.

 

[QWK]

Should I spend $800 on a TA49

WHOA!!! $800?? Check the "for sale" section....Try $675 SHIPPED

Here ya go.....

http://www.turbobuick.com/forums/showthread.php?t=167799

 

[ITSAV6]

????

Did you clean out your intercooler after the oil blowing turbo was replaced?
BTW,my car went 8.81(13.70-13.80 1/4) @ 15# ALL STOCK virgin down to the paper air filter and cat.
If yours only stalls 1500 @ 5#the conv aint right.
Back the fuel psi to 40-43,ever car is different(use a good gauge)
Clean out the ic
Go to a R42 plug for the higher boost
Make sure you have enough octane
Get a quality conv like a Pats 10",9X11,Precision 9.5,Edge 9.5.
Don't be scared of a 3000 stall with the stk turbo,you don't have to build much boost to get good 60ft times,you'll want a bigger turbo soon! :biggrin:

 

[TurboDave]

I've got a 255gph Wallbro hot wired. It's only a few months old. I was told by Precision that it would be enough to run with the 42.5lb inj and the stock turbo. The engine doesn't cut out or pop at all, only detonation that I can't feel or hear, which makes me think it's not enough octane (93 when I recorded the data-104/93 mix when I ran 14.45) for 20psi. Is anyone else running 93oct at 20psi? If so what is timing set at? Mine was 20 degrees.

Also, I do not have a D5 converter. I think this one goes in a van or somthing. It came with the car. I'm ordering one from TCS, 2400stall 12" l/u for $200 plus shipping.

Yes, I run 20# of boost on 93 octane (with less than half a degree of KR). And do it successfully.
You can read my setup and times here:
http://www.turbobuick.com/forums/showthread.php?t=168852

My setup is a little different than yours, and while I agree, you probably need a better converter, that's not all that's wrong. Your state of tune probably has a lot to do with it also.

I've only been tuning this car for 20 years now, but still learn a trick or two now and then.

As far as 20# on 93 octane being suicidle, I couldn't disagree more (obviously). It's all in the tune, and setup.

BTW, hitting 7° of KR with 20# of boost IS asking for major trouble!!!

 

[XLR8]

[QUOTE
I've only been tuning this car for 20 years now, but still learn a trick or two now and then [/QUOTE]

Please note this information when tuning to 20# on pump gas.
I would consider Dave a true TR Guru.

 

[rob86gn]

Well I spent a little money- $200 on a convertor from TCS. They said I'll get 2400 out of it anyway. I'm taking it to the track this weekend. I got a knock gauge too. I spoke with Prec turbo also and they said to try 110 oct, 22psi, and 22deg. I also got S10 manual brake cyl and m/t drag radials. Wish me luck! Thanks for the help too!

 

[GNVYUS 1]

RobGN86, you know the stock D5 brake torques at 2800 rpm and builds around 5psi on stock GN's right?
Why would you step down to a 2400 stall and pay $200 to do so when you can get a stock D5 on the board for probably dirt?

And a 60/40 mix of 104 and 93 comes out to be around 99.5 octane, not enough IMO if you are running the Stock Turbo and IC at 21psi and 24 degrees of timing. Try a full tank of 104 and see what happens on the new set up.

My comment of running 20psi with 20 degrees of timing on 93 pump is just that, suicidal especially on the stock turbo and IC. Dave you have a bigger turbo ( lower outlet temps at same psi ) and a FMIC ( much better than stock IC at lower temps even more ) and you probably run less timing than 20 degrees ( not the same playing field anymore ). I would not recommend those #'s above to any newbie or average GN tuner to pull off. Dave you have a ton of GN experience, but I would not run your set up on straight 93 because its not worth the headache of blowing stuff up just so you can run 1 or 2 psi more and put the car on edge.

Sounds like you got it down , but you must be the daredevil type.

 

[TurboDave]

RobGN86, you know the stock D5 brake torques at 2800 rpm and builds around 5psi on stock GN's right?
Why would you step down to a 2400 stall and pay $200 to do so when you can get a stock D5 on the board for probably dirt?



My comment of running 20psi with 20 degrees of timing on 93 pump is just that, suicidal especially on the stock turbo and IC. Dave you have a bigger turbo ( lower outlet temps at same psi ) and a FMIC ( much better than stock IC at lower temps even more ) and you probably run less timing than 20 degrees ( not the same playing field anymore ). I would not recommend those #'s above to any newbie or average GN tuner to pull off. Dave you have a ton of GN experience, but I would not run your set up on straight 93 because its not worth the headache of blowing stuff up just so you can run 1 or 2 psi more and put the car on edge.

Sounds like you got it down , but you must be the daredevil type.

That's why I provided a link, so that everyone would know what setup I run. Yes, 19/17 is my timing. As for any of this being dangerous, that's not really a fair statement. Since I'm very carefull to monitor knock, and have never seen so much as even a degree of KR. The highest I ever see is maybe .6 on a really hot day, 99% of time theres NONE. There's really not enough strain on anything for it to blow up.
As for the turbo, it's only a 44 so it's not "that" much bigger. Yes, the front mount probably does make some difference. Maybe I out to try and crank the boost up on my 87 to see if I can get it to knock? It's only running 18.5# now, Because it's all stock.

 

[gn4u2c]

you need someone with experience to look that car over and tune it . my T ran 13.8o's every time when it was dam near stock had a K&N drop in factory box and a test pipe thats it!! factory chip,boost everything stupied worn out 215 dunlops on it.
put it was in tip top shape

 

[rob86gn]

I spent the money on the convertor because mine is not stock and I didn't know of anyone that had a D5. As I said earlier, someone rebuilt this trans and threw in a van convertor. It wont budge over 1500rpm.

 

[Blazer406]

I just got done driving my car for the first time after installing a Vigilante 5 disk "0-pump" converter.... in preparation for installing my TE61 in the next week or so. I am still running the stock turbo.... I replaced the valve springs and installed a THDP 3" SS w/test pipe last week..... I drove the car for several days with the new DP and valve springs... and was impressed the difference over stock..... Well... after tonight.... even with the stock turbo..... the converter made the stock turbo boost instantly.....no hesitation..... 0-15 psi boost from 20 mph @ steady speed....... and nail it takes about 1 second to get to 15 # of boost :biggrin: then the street tires are begging for some grip......

I still believe you have some tuning to do.... but the converter will definately help as well...

Keep us informed of your changes/results....

I plan on going to the local 1/8 mile track tomorrow night..... to see what my changes netted...... wish me luck.....

 

[Blazer406]

I plan on going to the local 1/8 mile track tomorrow night..... to see what my changes netted...... wish me luck.....

Last time at the track..... bone stock except for the K&N.... went 9.20 @ 73 in the 1/8...... with a 2.06 60'....

Installed the converter and DP in my sig and replaced the valve springs.... all else unchanged.... went 8.46 @ 79 with a 1.84 60' ... .7 sec and 6 mph out of valve springs/DP/converter.... all else pretty much stock.... 8.46 should be around 13.30 thru the quarter if my math is correct..... I am pretty happy so far....

 

[jamericaniSS]

How does the car drive now that you have a 3200 L/U as opposed to the stock stall. Can you notice the difference in stall.

 

[Blazer406]

Drives great.... hardly notice it much with light driving.....

mash on it.... and wow!!!!!!!!! nearly instant torque...... I guess because of the faster spoolup.

 

[QUIP'6']

I did some testing on the street and recorded some data. O2 was 769mv WOT, I had 7.3 deg spark retard with 93octane and a 20 deg chip. Full exhaust, plugs gapped at .035 R44's. Boost 20psi. I don't think the convertor is a D5 - only stalls to 1500rpm max with drag radials @ 20psi, it does lock though.

I'm definitly buying a converter (anyone use TCS' 12" l/u?), using higher octane fuel next time- probably 111 unleaded.

On the 14.45 run I had radial t/a's with 32psi. Didn't matter because the car wouldn't even spin them until second gear. I also think it's running rich. I have 42.5# with stock turbo @ 45 psi fuel press with line off.

that is a d-6 i had one and it went 1500 4psi off the line that was the gas to the floor went with a restalled d-5 and i get 14 psi at 2800 rpm off the line

 

[rob86gn]

That's encouraging. I put this convertor in that was supposed to go to 2200-2400, it only went to 1800 (300rpm higher than the ol truck/van convertor it replaced). Anyway between that, the S10 wheel cyl, and m/t drag radials, it helped me to get to 13.78 @98 on 20psi. My 60' is still weak at 2.2...I couldn't get more that 5psi off the line. I'm going to see if I can return this convertor and get a true high stall convertor for next year.

My trans is slipping in 1st and 2nd now so I'm done for this season.