T3 vs T2

[WDRacing]

I just wanted to get this info out there. I see alot of people making what I consider to be a mistake. The T2 flange which encompasses the T25 and T28 turbo's are only going to be good for a fairly low boost setup. The KA24DE is a fairly large 4 banger and needs to breath if you want to make decent power. The T25 and T28 are for sale for very cheap everywhere, and so is the bottom mount SSAC manifold. Which for the record, isn't as bad as the top mount.

The combination of cheap mani and cheap turbo is swaying people to go with what I believe to be a mistake in turbo sizing. If you want to upgrade your turbo so you can run more boost later down the road, then you have to also swap out the manifold, which will lead to redoing almost all of the piping as well.

The term lag is used very loosely in this forum. The T3 super60 or any variant of the T3/TO4E in the proper trim will have no lag.

The T3 flanged turbo gives you almost limitless options with manifolds and turbo's. You can easily reach the max power limits of KA with a T3 sized turbo. I can't think of one single reason to pick a T28 over a T3.

I just want all of the newer members to know what they're getting into when they make the initial choices.

WD

[Terran]

Was this pointed at me? HRMMMMMM!? i am not going to use SSAC! My problem is that most T3's are rather expensive, where as a BB T28 is rated at 300hp and is cheap in comparison.

[WDRacing]

Show me a real BB center section T28 thats cheaper then a T3 and I'll show you a turbo made in China.

The JGY is the same exact thing as the SSAC bottom mount bro.

WD

[Terran]

Show me a real BB center section T28 thats cheaper then a T3 and I'll show you a turbo made in China.

The JGY is the same exact thing as the SSAC bottom mount bro.

WD

Yeah i cought onto that, usually they're pretty respectable so i didn't expect them to sell crap, but the revhard manifold (if i can find one) looks good. I'm just going off the JGY prices for turbos. What would you suggest for a T3 for 250 - 300hp and a maifold?

[WDRacing]

http://www.jgstools.com/turbo/index2.html

[Jookmasta]

i also wanted to throw in that a turbo upgrade for a t25 or t28 flanged mani is much much more expensive than a t3 flanged mani. you can definitely get a t28 turbo that might be good to 400hp but expect to pay mucho dinero for that turbo and it will most likely be water cooled. just remember that it's always best to plan one step ahead just in case the boost bug bites ya.............
Modified by Jookmasta at 12:46 PM 12/8/2006

[crzycav86]

It's true that the t25 is an undersized turbo, but you can't beat the performance value of the ssautochrome/sr t25/ebay setup. 220whp for less than $1200?? Sign ME up. Too bad you won't be getting much more than that though. It's enough for some people though while money is tight.

For the record my setup is not the ssautochrome/t25 setup, but I wish it was.. it would have saved me a lot of money and a ****load of work.

[WDRacing]

That is true...you can't beat the price.

[TrunkMonkey]

My problem is that most T3's are rather expensive, where as a BB T28 is rated at 300hp and is cheap in comparison.

don't ever pick a turbo based on a HP rating.

-demetrius

[WDRacing]

OK, I deleted a bunch of crap posts so don't freak out. This thread is staying on topic. If you want to discuss the differences between T25/T28 turbo's and T3+ thats fine.

This thread isn't about what fuel management is cheapest...thats just gay, don't let it happen again. If you're going to ruin one of my personal threads, you'd better post pics of hot chicks!!!

WD

[ownnij]

funny im in the middle of building my ka-t *stock block* and i first went towards the big setup and now im leaning towards the smaller setup. mainly cause its probably gonna cost a lot more for the big turbo setup for my small reliable goals. im only aiming for like 230-250 and im pretty sure a t25/t28 can achieve that but yet im still temped to just do the bigger turbo setup cause ive already got the turbo but man turbo manifold/downpipe are expensive not including the wastegate... WHERES MY MONEY TREE

[KATwo40]

The issue here is that people tend to overlook the equally important turbine side of these T2 series units on the KA.

Sure, the compressor is rated to 25 or 28 lb/min, but remember, this little turbo, because of it's restrictive exhaust, is flowing these numbers way too early on the KA.

Then, you run into issues of exhaust gas reversion into the cylinders, making for higher cylinder temps and pressures than you'd find using a T3 60 trim at the same power level.

Conversely, a T3 super 60 could be had for around $350-400 with an integral wastegate. That's not too shabby, if you really consider that these Ebay used T25 and T28 units are pretty close to worn out for not much less money.

And, I must agree with WD, in that the term "lag" is used quite incorrectly, not only on this forum, but on many others.

The rpm at which boost pressure will be created is called boost threshold. NOT lag. If a T25 makes 12psig at 2500rpm and a T3 super 60 makes 10psig at 2800rpm, the T3 is not laggier than the T25. It simply has a higher boost threshold.

The term lag is in reference to the turbo's response to exhaust gas flow at a given rpm. As rpm's rise, lag decreases. A standard journal bearing T3/T04E will have less response to exhaust gas than a GT35R because the GT35R has better bearings, lighter wheels and less inertial mass.

[ownnij]

yea i agree with that but im just saying if your budget builder and dont have any hp goals. the t25/t28 is the best way to go but i dont know you make going with a t3+ is well worth it

[ownnij]

i just wish that there were cheaper manifold/dp combos for the poor people that cant afford the $800 manifolds

[WDRacing]

One thing I see happening is 2 years at most from now, you guys will all be looking for turbo rebuild threads...why cause you bought a POS off of Ebay.

It's not like an intercooler or some other stationary object that does basically nothing, we're talking about somthing that spins 60,000-90,000 rpm. While those of us who bought quality units can enjoy around 100,000 miles of driving. At which point the only things we change are the bushings and 2 oil seals.

I'm glad someone brought up the fact that the compressor housing only determines flow. I can run a T25 exhaust housing and a TO4R compressor...do you think I'll be able to use all the CFM it produces...how about no.

WD

[GTR PrYdE]

If this is off topic please delete, but where are good places to get T3s without breaking the bank? I don't usually see them for less than 350-400 bucks, when I happen to run across them.

[S13FX]

350 - 400 is usually what they go for and thats in pretty good shape too. I bought a T3/T04b from a forum member for 350 well worth the price too.

[GTR PrYdE]

Yeah I was just wondering about shops/sites that sell them, as I usually only see private sellers

[KATwo40]

I've been running an SSAC topmount manifold for 2 years now.

That's less than $200.

[GTR PrYdE]

I've been running an SSAC topmount manifold for 2 years now.

That's less than $200.

what did you use for a midpipe to bolt to the sr downpipe?

[KATwo40]

I don't use an SR downpipe. I use a custom 3" downpipe.

The flange for the back of a 5-bolt T-3 turbo (the most common style turbine housing) is about $20. Then, you can purchase a piece of mandrel bent 3" exhaust pipe for pretty cheap, take it to the local exhaust shop and say, "Make this fit."

In the end, you might have $100 in a downpipe.

The main misconception I find in this whole KA-T forum is "I can turbo it, be super fast, reliable and for cheap!"

The bottom line: Speed = money. So, how fast you can afford to go is what it comes down to.

[ghx407]

What's your opinion on a T28 with a .60 compressor and a .64 turbine? Do you think it's a good balance between boost threshold, mid-range torque and top-end power? It's what I'm running in my KA-T and it feels pretty good, but then again it's the only turbocharger I've used in my car. I'm doing 10 psi, just in case you need to know to give me an adequate answer. Thanks!

[ownnij]

i ran a bottom mount ssac on my sr for 3 years and no cracks but the top mount for ka looks like a pain in the ***. mainly cause not enough clearance between the turbo and MBC but if anything besides that i would get it on asap. can a muffler shop really fab me a downpipe? haha i didnt think about that... i always wondered where i can get a downpipe for a bigger setup without spending a grip

[Terran]

I am looking at their T3 kit, awe you mods are so considerate, looking out for people who act like total newbs like myself. **** SSAC!

[KATwo40]

What's your opinion on a T28 with a .60 compressor and a .64 turbine? Do you think it's a good balance between boost threshold, mid-range torque and top-end power? It's what I'm running in my KA-T and it feels pretty good, but then again it's the only turbocharger I've used in my car. I'm doing 10 psi, just in case you need to know to give me an adequate answer. Thanks!

It really depends on the power you seek, and where in the rpm range you want it. If you want something that comes on hard, can easily break the tires loose and is a little squirrely comin' out of the corners, that's the turbo for you. The torque line on a dyno with that turbo is pretty much a steady flat line.

At 10psig, you're nearing the end of it's usable range on the KA. Yes, it can be run on up to 15psig, but with the high exhaust output of the KA, you'll run into exhaust choke around 10-12psig.

If you were to hit the drag strip next to a car with the same peak horsepower via larger turbo (larger turbine housing), you'd see that the other car would pull away from you as you approach the upper end of the rpm range. Probably your power begins to fall around the 4600rpm mark.

In my opinion, a properly sized turbo, even for a fun street car, will have a boost threshold of no more than half the max rpm. So, if your redline is 7000rpm, then anywhere around the 3000-3500rpm mark is acceptable. The benefits of not having full boost at 2000rpm are many fold. Some that come to mind are smooth power roll-on, better fuel mileage at cruise speeds/rpm, more top end flow, less chance for exhaust gas reversion. And the list goes on.

However, please don't take my words as a slam against your setup. I've had some of the most fun in cars with "too small turbos." That snappy response is quite addictive. Just understand that, if you want to make more power any time soon, a larger turbo will be in order.

[Florida240sx]

My friend with his small turbo leaves me behind in 1st. 2nd gear I catch him, 3rd gear he is dust.... On a side note with my t3/t4...I hit boost in reverse So et a turbo that can support you down the road, because you will get the boost itch

[Jookmasta]

u know i never thought about trying to hit boost in reverse lol....................got something new to do on the things to do list.

as the other two said, when the boost bug bites, ur gonna wish and wish that ur mani could take a t04e turbo on it cuz the money to upgrade so that u can use such a turbo is gonna hurt. and to whoever said that u spend extra money due to an external wastegate, remember that most t04e with a .48 a/r have the internal wastegate option so that point is mute.

[WDRacing]

Internal gates suck....

[ghx407]

My power goal with the T28 is 220-230 HP. I haven't put it on the dyno yet, but I think I'm extremely close to it if I haven't reached it yet. I've beaten WRXs, 5.0 and 4.6 Mustangs, etc. with my budget build. My cousin's 527 HP Civic killed me, though. When I finish college I'd love to do an all out setup with 8.5 CR pistons, forged rods, a GT35, stand-alone engine management, blah, blah, blah, good for 350-400 HP.

[S0lid_Snake]

WD, how is a T3/T04E .63A/R turbonetics ball bearing turbo for spoolup? its ball bearing so it should spool faster than a similar sized non ball bearing, thouse the .63A/R housing.If this is a noob question forgive me, but this is the turbo i had planned on, and it would be nice to have someone with your experience lend some insight