3.1 turbo-what would be needed for twin turbo?

[no_doz]

im trying to get some ideas what to do with my refund & i soon will be getting a 3.1 turbo out of a tgp, & my question to you guys is what all would i need to convert this to twin turbo-how would i hook it up (would i get another turbo of the same size or a smaller turbo to help with turbo lag or a small and a large one-??) also how much boost could i go on the stock bottom end & a 90 lumina 3.1 4 speed auto trans before i destroyed one or the other? & how hard would it be to find someone to program an ecm for it if i happened to luck across a 5 speed to swap in place?

if at all possible id like to have large enough turbos that i have plenty of lag if that would mean that while in town if i was tame on the pedal maybe it wouldnt eat me alive on gas-am i incorrect in this thinking? thoughts?

thanks guys

[no_doz]

so far i know id need

2 turbos or 1 large turbo
high cap fuel pump
larger injectors
ecm tune??
of course an intercooler
boost controller
boost gauge
misc intake & exhaust piping

then what else?

[IsaacHayes]

1 larger turbo would be the better bet. You don't have much room for TT anyways. The stock turbo on the TGP is on the small side anyway, even for the 3.1mpfi.

[TiredGXP]

I've been looking through turbos for a 3.1 for a couple of weeks.

Many of your questions about turbos can be found here: http://www.turbobygarrett.com/turbob...ch_center.html . Work your way through the Turbo Tech 101, 102 and 103 pages.

In order to properly size your turbo you really need to understand what the N/A volumetric efficiency is. The peak is probably in the 85-90 % range @ torque peak, dropping off to either side (more on the higher rpm's). Maybe someone can post up the WOT VE for you.

A great site for plotting data on various compressor maps is: http://www.squirrelpf.com/turbocalc/index.php .

At any rate, for the iron head 3.1, it looks like the GT2860RS is a great match up to 10-12 PSI

Cheers

[no_doz]

this is an aluminum head engine & i want tt just for the fact that it is tt (bragging rights, ya know)-if i got 2 stock 300zx turbos or 2 smaller turbos-wouldnt that be sufficient? imlooking for mid to high 200's but id like to have ttjust to have it-even if my gains werent/arent above that of a a single larger turbo :P

thanks, doz

[project89]

I've been looking through turbos for a 3.1 for a couple of weeks.

Many of your questions about turbos can be found here: http://www.turbobygarrett.com/turbob...ch_center.html . Work your way through the Turbo Tech 101, 102 and 103 pages.

In order to properly size your turbo you really need to understand what the N/A volumetric efficiency is. The peak is probably in the 85-90 % range @ torque peak, dropping off to either side (more on the higher rpm's). Maybe someone can post up the WOT VE for you.

A great site for plotting data on various compressor maps is: http://www.squirrelpf.com/turbocalc/index.php .

At any rate, for the iron head 3.1, it looks like the GT2860RS is a great match up to 10-12 PSI

Cheers

no reason to do twins its more trouble then its worth specially ony a fwd car
on a stock iron head the gt30 is a better choice any top end work and go right to a gt35, on an aluminum head motor the gt35 will work pretty dam nice as well

if u want a cheap turbo go grab an holset hx35

[no_doz]

why is it more trouble than its worth? i would like an in depth explanation on this from someone please. i realize that it would be overkill & that id prolly end up sending a lot of boost out the BOV but just to know its twin turbo-unless its a HUGE pain over getting a larger turbo & putting it on, i want to do it. yea i know im stubborn as hell, but i figure if tons of 300zx's can do it i would certainly hope my beloved chevy would.

[IsaacHayes]

TT on a transverse engine setup is gonna be cramped. No real benefit either. Many TT factory cars that get modded go to one big turbo anyway.

[no_doz]

for all i care ill cut a giant hole in the hood & get a cowl induction hood to accomodate. HA!

[IsaacHayes]

More impressive would be a single turbo done right making it a fast car rather than some hacked up job to put twins on.

[Guest]

I can see you're new to forced induction.

Grab the books Maximum Boost by Corky Bell and Turbochargers By Hugh MacInnes. Both of these books are good, "Turbochargers" is a more technical read, while "Maximum Boost" is closer to lay-mans terms. "Turbochargers" was also originally written in the '60s and has had a few updates with later releases (my copy is from the '70s, there are later releases though), while "Maximum Boost" was written in the '90s.

TT can be done, if a single was always more impressive or a better way to go, Super Street racers would go with single 114mm or 130mm turbos instead of the twin 76mm or 88mm turbos that most do use.

Anyway, I have a pair of 300ZX turbos that I was, and maybe still will use on my 3500. I was looking more at the ability to spool fairly early in RPM for towing when I had a load on (GMC Jimmy), and be able to spool relativley high (in manifold pressure) at the lower RPM. Upper end would also be likely to drop off or over work the turbos.

I had looked at going TT in a Cavalier, and had most of the lay out figured out, it wasn't going to be a semetrical layout at all, but would have been quite neat to do. Went with a single because the owner of the car got a deal on a larger single.

It's a lot of work to fit more tubing, even though it will be smaller, than single runs of larger tubing, in most cases. I some areas splitting the tubing or using two smaller items might fit better.

[BillS]

It would seem that all you want is to have twin turbos and the hell with practicality or power considerations.

Why don't you do a proper single turbo installation that works and then stick in a dummy turbo that people won't be able to see just sits there unconnected.

[no_doz]

lol BillS that made me laugh. its about the same point, it would just be awesome to have the ONLY TT lumina ive EVER heard of (im sure there are probably a few, but not many), and if i ever went to sell the car (because i -am- hoping to start a family within the next year or 2 & itd be REALLY nice to get a year worth of baby shit bought ahead of time) i could get a lot more out of it just because im sure theres some jackoff out there that would be willing to pay way more than its worth, just because its a fast twin turbo & one of maybe a dozen, half a dozen, etc... in existence. im looking for 250-300 hp & after that im looking for resell value & looks

[mfewtrail]

it would just be awesome to have the ONLY TT lumina ive EVER heard of (im sure there are probably a few, but not many)

There's a Lumina Z34 that has a twin-turbo V8 in it and that was converted to RWD. It's been around for at least a few years...

[no_doz]

lol yea but thats a drag car-completely custom & AWFUL on gas-id be looking for mine to be powerful but a daily driver.