3400 turbo.

[hotooimpala]

I just want someone to use it not really my cup of tea even as cool as the design is, btw I am a diesel tech in training so if me one wants to take the leap n try to make one work for a 60v, then I can get good condition VG turbos and I also can tune them and personally believe it wouldn't be horribly hard to dial in, since iv had them apart 15 plus times and have transferred one from an isx to a 3406B which is a largely different power band and hp app and injection system even lol but It was a simple spring and retaining ball swap and it ran like a dream..after a few try's of course

[hotooimpala]

Indeed!

[Guest]

Like I said, if you are poor go with a Holset. If you want a 35+lb turbo hanging from your engine, go with a holset. If you plan to drive your turbo setup for 500k miles, go with a holset. If you want a turbo designed for a Volvo diesel motor, go with a Holset.

[Alxsmt]

lol no offense. Im not getting a diesel turbo. im not into "throwing" random parts on my car. I like to know what they are going to do and how they are going to act.

[hotooimpala]

Obviously there are multiple styles of any brand of turbo..but I was just tossing ideas around you are right 99% of holset would be for us poor builds, but the VG is a whole different animal, it's like the Nsx it's not the best option for everyone as its expensive and has a lot of tech and all the hoopla, I mean ya honda is an economy car company..but the Nsx is the elite of that as the VG is to holset, except the Nsx would have to be able to switch between a quick revving tiny engine to a v8 beast every time the Roma go up to be an accurate comparison..(may have been a confusing rant)

[Guest]

Obviously there are multiple styles of any brand of turbo..but I was just tossing ideas around you are right 99% of holset would be for us poor builds, but the VG is a whole different animal, it's like the Nsx it's not the best option for everyone as its expensive and has a lot of tech and all the hoopla, I mean ya honda is an economy car company..but the Nsx is the elite of that as the VG is to holset, except the Nsx would have to be able to switch between a quick revving tiny engine to a v8 beast every time the Roma go up to be an accurate comparison..(may have been a confusing rant)

Confusing rant for sure. But it seems like you are stuck on the VG as being the end all be all. I'll try to break it down.

The Holset he351 with the VGT was designed for a diesel exhaust. Diesel exhaust is relatively cool. Gasoline exh temps run too high, and the holset exhaust parts werent designed for it. There will be issues.
The He351 doesn't use a standard t3 flange. It also doesn't use a T4 flange. You will have to have a custom flange made to bolt it to a crossover.
The exh outlet is a 3.75 inch outlet which is an oddball size as well. Then you have to find a way to stuff a 3.75 inch exhaust into your engine bay, or neck it down to 3 or 2.5 however you want it.
The turbo is physically large. the exhaust housing on it as well as the compressor housing are huge, and packaging will be an issue.
The turbo weighs 35+ lbs. I have heard some people quote nearly 50 lbs. Either way, its not light by any means. Imagine leaning over into your engine bay trying to pull that thing out over and over again while you fab up your exhaust.

Now there is a VGT turbo that you can buy, that was designed for gasoline engines and is made by borgwarner so you are in luck if you are stuck on wanting a VG turbo. They are much more compact and don't weigh as much as the holset 351 too. Full-Race sells them, as well as other places. They came on Porsche 997 GT2s around the 07 model year.

Remember, if you go this route, you will prob want to get two of them, since a single one would prob be way too small for a 3400-3500 motor. Porsche used two of them. Here is where you can get it. Remember you will need two of them.

http://www.full-race.com/store/turbos/borgwarner-airwerks/borgwarner-bv50-vtg-turbo.html

I found a pic comparing a t3 exhaust housing with a 351ve exhaust housing. which one do you think weighs more and which one will be harder to package in a tight fwd GM engine bay?

[Guest]

I cant figure out how to read maps for the life of me.. well from what I can see on garrets site nothing is in the boost range im thinking about running so im not sure if it really even matters too much as long as the turbo isnt too small

the plan - keep my current 3400/3500 10.5:1 cammed engine but regap the rings for boost. start with 3psi and see where it goes from there. Im thinking no more than 5 on this engine. pump gas. when the engine goes, maybe 10psi on a "stock" 3400. I have been cleaning up my engine bay and making room for the past year.

everybody seems to love the gt35 but I dont think I will need a turbo that big.

I want boost to kick in at about 3000-3500, power kept in the upper rpm range till 7k max

Going back to your original post there are a few things you are wanting, but might not be possible. You want to run 3-5 lbs of boost, which isn't a lot by any means, which means you don't need a large compressor wheel. You then state you want boost to come in around 3000-3500 rpm, which means you will want a larger compressor wheel so that it is a little laggy. Its either a larger comp wheel, or a larger exhaust a/r.

If you go with a smaller comp wheel, it of course will spool quicker than your proposed 3k rpm. If you go larger, you could run into compressor surge which is bad. The other option is a smaller comp wheel, with as large of an exhaust a/r as you can get. The problem with that is that when you go with smaller comp wheels, you are limited on the size of your exhaust a/r because turbo manufacturers use housings to match the size of the exhaust wheel. Larger wheels usually require larger housings. Like .82 or 1.0

A gt35r size turbo is a 61mm compressor wheel. Now there is a gt35 wheel that is not the R version. R just means ball bearing to garret, but either way, the gt35 and the 35r is a different compressor wheel size. A 61mm will still spool quick on a 3400. Especially with your higher compression that you are running.

My recommendation based on what you are claiming you want, will be a compromise. It will be a smaller comp wheel, but I am going to recommend the largest exhaust a/r you can get which will help with slowing the spool. If you decide you want a quicker spool, you can simply swap exhaust housings.

I recommend this turbo. Its a 59mm comp wheel with a 62mm exhaust wheel. I feel you don't need anything larger for the boost you plan to run. Also with the comp wheel being smaller, it should help with not surging. A .82 exh a/r is also available which I would recommend if you want your boost to come in as late as possible.

http://realstreetperformance.com/store/precision-59mm-5252-turbo-590hp-journal-bearing-t3-t4-t350-2468.html

This turbo is good for 600 hp, which is more than you will prob ever need. It is a great street turbo.

[TGP37]

I can't offer as much advise as the next guy, but I can say I run a knock off T04E-50 on my 3100 at 8 psi (sometimes 10-12 ish) w/ a 0.63 AR Turbine. She spools up real fast and holds all the way to 5500, barely.

You may want the next size up being you have higher compression and more displacement, but not by that much.

You REALLY want to learn how to read turbo maps. If you want a city driver, plan the turbo to be most efficient at peak torque. For a race car, best efficiency at peak HP.....as I was told.


Once you learn the maps, it's like, wow that is easy. A LOT of questions you may have become answered.



Also dealing with exhaust diameter....are you keeping stock exhaust or upgrading? 2.5" is good up to 400-450 HP or somewhere around there. 3"+ exhaust is nice but hard to pack into an engine bay not built for boost. A stock exhaust will provide greater back pressure, reducing the pressure ratio across the turbine....effecting spool and over all performance.

Hope this helps some.

The advise offered here is GREAT advise, these guys, the regulars, are very wise. They helped me succeed in my 1st build.

[hotooimpala]

Ya it was a late night and I had had a few lol, and what temps do our gas exaust run then? Since diesel uses heat and compression to ignite there fuel compared to a card spark, I'd personally think gas manis would run cooler to a point

[Guest]

What's wrong with using a turbo from a diesel?

I have a Borg Warner from a 6.5L diesel on my gas 2.8L I6. IMO it's a bit large for the application, boost starts in the 2500 RPM area, in 3rd gear (higher RPM in lower gears), and have 12 to 14 PSIG by about 3300 RPM. Near the end of last year after some tuning I was getting close to 20 PSIG by the 3300 RPM mark. Boost hits hard, which is fun, but can cause a loss of traction once boost hits.

The idea of wanting lag to promote traction just doesn't hold water, especially once you get to wanting more power, meaning more boost.

To get the idea of lagging boost to promote traction to work, you want a more linear build in power, meaning a more linear build in boost pressure. Turbos not act like this, at least not without some controls set up to make it act that way.

But you know what does act that way?

A supercharger has a more linear build in boost pressure more directly linked to RPM than a turbo does. Load on the engine does play a role, but the build in power tends to build more linearly, helping maintain traction once it is established.

Personally, instead of trying to maintain traction by limiting power, I would look at chassis improvement and wheel/tire combos as ways to gain traction to try and get as much power to the ground as possible.

I also wonder why you have to have an externally gated turbo?

I'm running an internally gated turbo, and other than a poor selection in wastegate actuator, I have had no issues in boost control. With my current spring addition, my minimum boost pressure is about 9 PSIG. With less springs, I was able to be down in the 3 to 5 PSIG range. And as I have mentioned I have seen upwards of 20 PSIG with this same turbo.

If you want to select a turbo that you know works on a combination, find someone running something similar to what you are, and copy that set-up, otherwise you can read all the maps you want and while you may choose one that works closely to the way you want, you'll never know for sure until it's actually running on an engine. I'm also not sure you'll find anyone who had the same desires to build a laggy set-up, since most people want boost to come in as soon as possible, to get the most out of their power bands.

[TGP37]

A better differential like a limited slip will definitely help with traction.

A lot of practice making a great driver will solve the traction issues as well. Knowing exactly where to put the throttle and how to ease in with out spinning out really helps.

[hotooimpala]

Good point..I'm clone randomly talking about diesels though, are you ever going to go high boost or you plan on sticking to some low boost levels? If you ever plan on going high might as well lower compression with forged pistons and 3500 heads up, but then again I'm planning a 3.4 turbo impala at 12-15 psi on all stock except ported 3400 heads lower an upper so I guess you could see if I explode first before Gavin to buy the 3500 stuff and pistons

[Alxsmt]

thank you for the replies!! the more I know the better off I am. Im not saying a diesel turbo cant and wont work, im just saying I dont want to go that route.

yeah I was thinking what I want might not be possible unless the waste gate is open 90% of the time with a huge turbo.. I cant see going crazy high on the boost, mainly due to traction and the fact I do more auto cross than drag these days. most I could ever see myself doing is 14, and not on this engine. I will look into that link, thanks!

external wastegate is mainly because I want to put it where I want it, not hanging off the turbo. better adjustability. the screamer pipes sound awesome too

I have thought about the supercharger route but to me thats too complex, exhaust work is easier plus I like the idea of boost only when your in a load. and I REALLY hate my headers.. haha

the car isnt daily driven these days, mostly to the track and back, or towing a jet ski.


as far as traction issues, I currently have issues hooking up in 2nd from a roll.. when its dry. hoosiers are a life saver for the drags yet I can still chirp those pretty good in 2nd.

here is a full list of how the car is currently setup:
engine:
-3400 block
-3500 top end
-polished and cc matched combustion chambers
-3 angle valve job
-comp cams springs, valve locks and retainers
-reground cam 264.6/264.6@.006 duration, 533/533 lift, 110 LSA
-custom pushrods
-cyrogenic treated rods
-je pistons 10.5:1
-paralled block
-65mm tce throttle body
-modified and ceramic coated S&S headers
-2.5" mandrel bent exhaust with magnaflow muffler and cat (plan on keeping it for boost)
-solid engine mounts
-mrz polly trans mount
-megasquirt2 EMS, stand alone.
-innovate LC1 wideband
-flow balanced 28# injectors
-balanced engine
-engineered performance LSD (worn out, getting a rebuild this winter)
-clutchmaster stage 3 clutch
-the drive shaft shop 400hp axles

suspension/brakes:
-Eibach springs
-koni yellows shocks and struts
-rear shock tower brace
-GM strut tower brace
-all bushings are polly
-addco 1" rear swaybar
-92 brake upgrade
-hawk hps pads
-ss braided lines
-16x7 with 225/50/16 dunlop durezza star specs (street)
-17x7 with 225/45/17 kumho v710s (auto cross)
-16x7 with 225/50/16 hoosier drag radials (drag)

plans in progress, installing winter:
c5 front and rear brakes (calipers and rotors)
dual masters
18x8 with 235/40/18 dunlop ZII (16s wont fit over the rotors..)
rebuilt LSD and probably trans too.

[Guest]

For Auto X, I would go supercharger, it will work better with the transient changes in load. A large turbo will just be more ballast, and cause traction losses when the boost comes in, which can be disastrous when exiting a turn. Like I said before it's difficult to get a turbo come on smoothly, without spending a lot of time, effort and or money on doing so.

At this point I think your time and money would be best spent on the chassis and not trying to make more power. You say you already have traction issues, more power will only make that worse.

[Alxsmt]

yes but I dont want to deal with the bet side or constant boost at highway speeds. im very picky I know lol. by the time I add brakes and 18s It will slow it down some. plus a cage.. then I will need power to make up for it and the lsd rebuild should help with traction a LOT. really not much else I can do to the chassis other than rwd.. or custom springs/coilovers

whats every ones take on billet vs cast?