Turbo for a Series II motor??

[cstavro]

iB::Topic::3800 Series III Turbo...

Here is all the info but it has not been updated for a while, it is a very good read so have some popcorn ready. Very impressive work indeed; I don't think anyone that I have seen so far in the 3800 community has used the theory of pulse turbocharging to its full potential. What he did goes beyond using twin scrolls.

it took me over 5 hrs to read the entire thread! all those useless posters, and two failed hijack attempts didn't help. lol

i haven't heard of anyone in the 3800/gn community either. he uses twin scrolls aka divided housing. he guesses that the single wastegate doesn't hurt. the thing is, it still isn't tuned as of june 2007 (2 year project!), and hasn't had it wot.

i got lots of great ideas, plus where nocutt himself said he would have done things differently. the biggest one: either get a kit, or fab everything up on a donor car first! hp tuners and a custom file to at least get you going. zzp says you can install their kit in 6 hrs. thanks again for the link.

i haven't gotten ANY feedback from sellers on a divided t4 housing. i'm leaning towards the gt61-6776rs with 3 bolt! precision can get me a pt61 t4...at a higher price than limit or full throttle

 

[bison]

Pulse tuning may be something to look into but the basics still apply. Those are to have a decent pressure ratio between intake manifold and exhaust pressures. The BB turbos allow us to run a larger a/r for the same 2 wheels without trade off on spool up. Converter selection becomes easier also. Id go with the largest exhaust a/r that you can stand and or use a little N2O to spool an even larger a/r. Getting the exhaust pressure down while having the intake pressure high will increase power tremendously. Its possible to have higher intake than exhaust pressures with the right combo. Nitrous is almost always used to achieve a pressure ratio like that and may not be acceptable on the street even though it only takes a tiny bit of nitrous to spool the turbo with the bigger a/r's.

 

[bison]

iB::Topic::3800 Series III Turbo...

Here is all the info but it has not been updated for a while, it is a very good read so have some popcorn ready. Very impressive work indeed; I don't think anyone that I have seen so far in the 3800 community has used the theory of pulse turbocharging to its full potential. What he did goes beyond using twin scrolls.

it took me over 5 hrs to read the entire thread! all those useless posters, and two failed hijack attempts didn't help. lol

i haven't heard of anyone in the 3800/gn community either. he uses twin scrolls aka divided housing. he guesses that the single wastegate doesn't hurt. the thing is, it still isn't tuned as of june 2007 (2 year project!), and hasn't had it wot.

i got lots of great ideas, plus where nocutt himself said he would have done things differently. the biggest one: either get a kit, or fab everything up on a donor car first! hp tuners and a custom file to at least get you going. zzp says you can install their kit in 6 hrs. thanks again for the link.

i haven't gotten ANY feedback from sellers on a divided t4 housing. i'm leaning towards the gt61-6776rs with 3 bolt! precision can get me a pt61 t4...at a higher price than limit or full throttle

The 6776 3 bolt is a bruiser with a 3000 stall and a cam in the 210 degree range. Id go .63 unless you go BB or if you want to slow the hit down a little go with the .85. You will have a 130 mph car with a good tune, heads, intercooler and 28 psi boost.

 

[jbunla]

it took me over 5 hrs to read the entire thread! all those useless posters, and two failed hijack attempts didn't help. lol

i haven't heard of anyone in the 3800/gn community either. he uses twin scrolls aka divided housing. he guesses that the single wastegate doesn't hurt. the thing is, it still isn't tuned as of june 2007 (2 year project!), and hasn't had it wot...

Actually it is tuned at low boost like 6psi or so, the last I heard; my relative is very close with him. It is funny he was the first to turbo a 3800sII back in 1997 so I wouldn't dismiss the fact the car has not gone WOT as anything but at his own time/pace :smile:

...i got lots of great ideas, plus where nocutt himself said he would have done things differently. the biggest one: either get a kit, or fab everything up on a donor car first! hp tuners and a custom file to at least get you going. zzp says you can install their kit in 6 hrs. thanks again for the link...

Like I said above put thing into context, the fact he already knows how this engines perform without engine management in the past and got it working for another 7-8yrs is testament really. Remember this was before ZZP, stattama, hp or dhp. I still say go to fullthrottlev6.com and you will enjoy the variety of diy. Not much about kits there :wink:

...i haven't gotten ANY feedback from sellers on a divided t4 housing. i'm leaning towards the gt61-6776rs with 3 bolt! precision can get me a pt61 t4...at a higher price than limit or full throttle

Forget 3-bolt that is old school. I agree with Bison in terms of manifold design :tongue:

 

[bison]

Forget 3-bolt that is old school. I agree with Bison in terms of manifold design :tongue:

I agree. If there is room id use the tangential 4 bolt. Thats where the highest hp will be found.

 

[cstavro]

nocutt is taking his time...and i don't know how worthwhile some of his setup is. we can't tell until it's done!

he uses a T04S P trim 0.70 a/r with 58 mm compressor. he wanted midrange-top end power (instead of the 3500 rpm hp peak) just like i do.

i found someone - with p&p, cam, headers - whose power curve i like. it uses an master power t70 t4 .68 p trim. it peaked at 503 whp @ 5400 rpm @ 20 psig. the turbo starts spooling at ~3000, and full boost by 3600. LS1TECH - Pictures of one of my side projects... ST74 3.8L

do you think i can get away with the stock 2600 rpm converter with a bb gt6776? this will be with t4 divided housing. the other option is 3200 stall, and journal bearing turbo.

btw, fullthrottle can get the divided t4 housing i'm going to email mike on specific setup.

thanks

 

[JZ 97 SS 1500]

nocutt is taking his time...and i don't know how worthwhile some of his setup is. we can't tell until it's done!

he uses a T04S P trim 0.70 a/r with 58 mm compressor. he wanted midrange-top end power (instead of the 3500 rpm hp peak) just like i do.

i found someone - with p&p, cam, headers - whose power curve i like. it uses an master power t70 t4 .68 p trim. it peaked at 503 whp @ 5400 rpm @ 20 psig. the turbo starts spooling at ~3000, and full boost by 3600. LS1TECH - Pictures of one of my side projects... ST74 3.8L

do you think i can get away with the stock 2600 rpm converter with a bb gt6776? this will be with t4 divided housing. the other option is 3200 stall, and journal bearing turbo.

btw, fullthrottle can get the divided t4 housing i'm going to email mike on specific setup.

thanks

That link is the same as the link as posted above. We built that unit (ST74) for the customer after he intially tried an MP T70 with the .68A/R. He was not happy with the final #'s so he stepped it up on the turbo. He said the swap from the T70 to the ST74 only changed spool up by a small margin, but the turbo will make 900rwhp when pushed.

JZ

 

[nocutt]

nocutt is taking his time...and i don't know how worthwhile some of his setup is. we can't tell until it's done! he uses a T04S P trim 0.70 a/r with 58 mm compressor. he wanted midrange-top end power (instead of the 3500 rpm hp peak) just like i do.

...been done, I am curious "what do you think isn't worthwhile?";we can exchange and discuss ideas...

....do you think i can get away with the stock 2600 rpm converter with a bb gt6776? this will be with t4 divided housing. the other option is 3200 stall, and journal bearing turbo.

btw, fullthrottle can get the divided t4 housing i'm going to email mike on specific setup.

thanks

The stock converter is much lower than that...I believe it to be around 2200-2400. To run a turbo that big you will either have to do something about the dynamics of the turbine...I get useable boost by 1900RPMs all the way to redline, since I am FWD I opted to use an eBST controller to move the threshold a little higher to about 2500RPM...not heard of in the 3800 community with a ptrim and .70 A/R...

 

[CTX-SLPR]

Slight HiJac,

What are ya'll with Series II's using to tune with? HPTuners or the DHP? I'd get both if I could but I know they aren't compatable due to the encryption.

Thanks,

 

[nocutt]

I am using a a series III with series II wiring...I use DHP

 

[xXch0dyXx]

i dont have an l32 or l67 right now, but i still have the dhp powertuner ....

nocutt, its odd seeing you on these boards : - )

 

[nocutt]

i dont have an l32 or l67 right now, but i still have the dhp powertuner ....

nocutt, its odd seeing you on these boards : - )

Hey Chody...post here once a year about what happened to your setup...sold?

 

[xXch0dyXx]

yup, sold the setup to pay off the car. ended up getting a GN instead of turbo-ing it again, now im trying to get this thing to the level the old GS was on ;-)

 

[cstavro]

That link is the same as the link as posted above. We built that unit (ST74) for the customer after he intially tried an MP T70 with the .68A/R. He was not happy with the final #'s so he stepped it up on the turbo. He said the swap from the T70 to the ST74 only changed spool up by a small margin, but the turbo will make 900rwhp when pushed.

JZ

i'm away for 3 days and look what happens!

jz...yes, thank you. it's terrible having a short memory and googling mpt70 for hours

i don't just want 'street legal' or 'streetable' - i want a daily driver. i don't know what boost at what rpm makes a turbo 'streetable'. i also need to pass emission tests, and i want a stock quiet sleeper. last saturday i rode in a 1998 turbo regal gs, and the power really came on at ~3000 rpm...and i think 5 psi. he wasn't even flooring it.

 

[cstavro]

...been done, I am curious "what do you think isn't worthwhile?";we can exchange and discuss ideas...

nocutt - thanks for dropping in! the emphasis in my statement was on 'don't know', not 'not worthwhile'. as of last week, you hadn't posted any driveability or power figures in your thread. it's encouraging that you get useable boost at 1900 rpm.

cartuning states "This upgrade turbo is a 61mm PT-61 capable in excess of 700 crank hp with lagless operation... A turbocharger with boost by the time you are at 15% throttle." full boost by 2600. i believe it to be a p trim .63-.68 a/r t4. this turbo spools nearly as quickly as yours, and you use a boost controller to delay response - you might consider a larger compressor

i believe a 61mm p trim std bearing turbo will spool quickly, good for low 11s (with cam and heads), and i'll forego the 67.

being a stickler, i'd want equal length header tubes. a 12" length difference seems significant. i.e. cyl 1-5-3 fire at 0°, 240°, and 480°, respectively. the pressure pulses (independent of actual fluid speed) will reach the turbo at 35°, 270°, and 505° at 6000 rpm. they're still not arriving at equal spacings (the purpose of using a divided housing). i don't how this translates to spool or hp.

i've read that headers aren't worth the cost over stock manifolds even in a 10 second car logs benefit fab time, ease, and spool - and apparently don't lose much to full headers. i would, however, build the log with a 6°-8° cone instead of steps. 321 stainless, or even coated carbon steel is better than 304.

i also don't like the throttle body right above the exhaust/turbo. can you rotate the l26 intake 180°? this will also shorten the intake piping a couple of feet.

The stock converter is much lower than that...I believe it to be around 2200-2400. To run a turbo that big you will either have to do something about the dynamics of the turbine...I get useable boost by 1900RPMs all the way to redline, since I am FWD I opted to use an eBST controller to move the threshold a little higher to about 2500RPM...not heard of in the 3800 community with a ptrim and .70 A/R...

i've heard stock gs stall anywhere between 1800 and 2600 rpm. i've seen 2000-2200, but then i wasn't pushing it as far as i could. i hate the difficulty in getting good numbers. i've even gone to gm and i was told it's 'confidential'.

your car burbles...do you have the turbo cam in? i also hear the buick turbo snort

 

[nocutt]

nocutt - thanks for dropping in! the emphasis in my statement was on 'don't know', not 'not worthwhile'. as of last week, you hadn't posted any driveability or power figures in your thread. it's encouraging that you get useable boost at 1900 rpm...

LOL...the thread is never real time...never :wink:
Well I have this engine in a much lighter car and even the tire footprint does not really help. The tires go up in smoke so I had to artificially change boost threshold; between 2300-2600RPM dependent on the color of the sky lol. In any event, it is a testament to how the xhaust manifold was designed and other ancillary devices etc

...cartuning states "This upgrade turbo is a 61mm PT-61 capable in excess of 700 crank hp with lagless operation... A turbocharger with boost by the time you are at 15% throttle." full boost by 2600. i believe it to be a p trim .63-.68 a/r t4. this turbo spools nearly as quickly as yours, and you use a boost controller to delay response - you might consider a larger compressor
i believe a 61mm p trim std bearing turbo will spool quickly, good for low 11s (with cam and heads), and i'll forego the 67...

Well I cannot say first hand what the cartuning specs do, but I used a modified gn turbo years ago in a series2 and this was way smaller than what I have now, we are talking .60/.63 with a 4X mm comp wheel and boost came in at about 22XX-23XXRPM, fullboost was about 28XX-29XXRPM and plateau'd around 55XXRPM. A regular constant type turbo manifold was designed. In other words Cartuning is using a marketing ploy" over-rating" ...it simply does not make sense physically for them to be able to get fullboost by 26XXRPM. I will not go into their design specs is serves no purpose.
edit: I quickly went on clubgp to do a search here; good supporting info
ClubGP Message Forum troubleshooting

...being a stickler, i'd want equal length header tubes. a 12" length difference seems significant. i.e. cyl 1-5-3 fire at 0°, 240°, and 480°, respectively. the pressure pulses (independent of actual fluid speed) will reach the turbo at 35°, 270°, and 505° at 6000 rpm. they're still not arriving at equal spacings (the purpose of using a divided housing). i don't how this translates to spool or hp.
i've read that headers aren't worth the cost over stock manifolds even in a 10 second car logs benefit fab time, ease, and spool - and apparently don't lose much to full headers. i would, however, build the log with a 6°-8° cone instead of steps. 321 stainless, or even coated carbon steel is better than 304...

As you have seen it is very difficult to design "true" equal length headers with this claustrophobic engine space afforded by GM ...I am sure it is feasible but one needs lots of room to accomplish this. It is either you do a Pulse design or constant pressure system...they both have their merits, but as a street car my own emphasis lay in quick response, stock converter and a much broad power curve, in which case the pulse design was a better idea. The torque curve seems to be much broader like a "little turbine". Again different "means to an end". As far as hp and type of system goes, it is really difficult to say which setup favors power more granted we are working with what GM gave us. Again in my mind, the area under the curve should dictate that and since in this system the turbine is actually working much harder I would say there may be a much broader curve than a constant pressure system...that is an educated opinion, I will see when I get on a dyno...but definitely spool 101% faster.

...i also don't like the throttle body right above the exhaust/turbo. can you rotate the l26 intake 180°? this will also shorten the intake piping a couple of feet...

Never tried it (don't think it would fit...strongly), but for me it was a necessary evil...I am not a daily driver and that was a compromise. That area is wrapped, shielded and hood louvered, plus the tb is smaller less surface area to heat...
If you want the intake pointed the other way, you will likely have to design yours or get an FbodV6 (lot of work though)

...i've heard stock gs stall anywhere between 1800 and 2600 rpm. i've seen 2000-2200, but then i wasn't pushing it as far as i could. i hate the difficulty in getting good numbers. i've even gone to gm and i was told it's 'confidential'.
your car burbles...do you have the turbo cam in? i also hear the buick turbo snort

The supercharged version is around 1800RPMs, while the N/A variant is about 2200RPMs stall respectively. Now with a turbo behind I really don't know what it translates to...even higher stalls? never noticed it :frown:
I personally wanted to avoid higher stalls anyways.
Couple of folks swear that I have a "turbo cam" in there, but it is a stock cam...must be the tune :tongue:

 

[cstavro]

The tires go up in smoke so I had to artificially change boost threshold;

i want quick spool, and a flat torque curve. i'm sure i'll go with an electronic boost controller in the future. tires can only handle so much torque. innovative's solution was to quote me a turbo with delayed spool.

I will not go into their design specs is serves no purpose.

i was really interested in the pt61...until i was lead to you. i've requested a quote for a gt6176s divided t4 housing 0.7 a/r.

we are working with what GM gave us. Again in my mind, the area under the curve should dictate that and since in this system the turbine is actually working much harder I would say there may be a much broader curve than a constant pressure system...that is an educated opinion, I will see when I get on a dyno...but definitely spool 101% faster.

the stock cam and heads were made for idle to 3500 rpm torque. cam, heads, and shorter runners will really broaden the torque curve. i need 438 wtq @ 6000 rpm to meet my goal...and i don't want much more torque. popular setups make this much torque with only 300 whp i really can't wait for your dyno run

If you want the intake pointed the other way, you will likely have to design yours or get an FbodV6 (lot of work though)

what i want is a cad designed, cast aluminum intake...i think an l26 lim, fabbed upper and l67 throttle body is a very good compromise.

The supercharged version is around 1800RPMs, while the N/A variant is about 2200RPMs stall respectively. Now with a turbo behind I really don't know what it translates to...even higher stalls? never noticed it :frown:
I personally wanted to avoid higher stalls anyways.

i'm not a tranny guy, but more torque means lower stall. the turbo comes on after stall, so i'd agree with your statement that you never noticed it. i want stock stall too.

fyi, i discovered that accel fuel injectors make 150 um droplets. they call this 'ultra fine atomization'. toyota uses denso uc injectors that make 50 um droplets (fog ranges from 10-100 um, or .00004"-.0004"). this 1/3 radius means 1/9 volume...3x the surface area means 3x faster burn, more power, better economy, better emissions, and more stable idle. it's like the difference between wheat, which doesn't burn, to dust, which will annihilate a silo.

denso injectors are worth 3x the cost of bosch injectors, but i believe they're worth 3 mpg. increasing fuel pressure from 43.5 psig to 72.5 psig increases fuel flow and surface area by 29%. imagine what di does at 1200 psi! i also believe siemens injectors are better than accel. i hope siemens returns my call.

 

[Turbo6Smackdown]

Are there any kits to turbocharge the engines of the 88-90 buick century/skyhawk/lesabres at all?

 

[bison]

Are there any kits to turbocharge the engines of the 88-90 buick century/skyhawk/lesabres at all?

You would be better off starting with a series II since they are plentiful, cheap, and many options on kits are out there. You will spend less $ in the long run.

 

[Turbo6Smackdown]

I see. But how will the older computer work? Do the newer ecm's fit in the older cars?