chimmike

this isn't true, that's the issue.

7psi on a turbo pushing 20cfm at that ratio is throwing in a lot more air than a smaller turbo pushing 10cfm at the same pressure ratio....so the amount of air isn't the same....that's what I'm getting at.

While that's almost symantical, what DCG brought up matters the most in fighting detonation: efficiency of compression at x pressure ratio. If a t25 is more efficient at compression at 7psi, it's going to generally have a cooler charge than one not as efficient at the same boost setting.

Of course, I'm talking using an intercooler on every setup. I'd personally never run a non-turbo motor with a turbocharger and not use an intercooler....even a small one or an air/water unit with a good sized exchanger up front (which would probably work hella better with an aux fan on a 4x4 going such low speeds on trails.)

Sonofmayhem

WOOHOOO! well i got the debt settled for half the price, im gonna start saving up. anyone want to help me with parts? i guess i need a stock replacement turbo manifold a pretty high quality turbo( where should i buy it?) where are some kits that are just fittings and connections? i want to get a running turbo in then start with the fuel mods, i.e. larger injectors, and mega squirt hopefully youll be available.

^VooDoo^

Mike, I think your missing Bills point.
eg. If both Turbo sizes push more then 20cfm but the engine will only except 10cfm and both wastegates are set to 7lbs, Then the turbos look the same to the engine, The only difference between a larger one to a smaller one is that you wont have pressure falloff if you were able to go over the max cfm of the smaller turbo, But if you could use the smaller with out going over its max you would do better because the spinup is much faster.

You couldnt use a Cummings anyways, You couldnt build enough output exhaust from a 22RE to make the compressor spin up untill your 5mi down the freeway and it would most likely lag the engine till then.

I could have sworn Paxton had a supercharger for one of the Celica's with a 22RE

Bill

Ok, we have 2 turbos both pumping out 7psi(measured at the turbo), one pushing 10cfm, one pushing 20cfm (nunbers out of the blue).

The throttle body will stay a fixed size. What I'm suggesting is that to achieve 7psi measured at the throttle body the turbo pushing 20cfm won't have to work as hard as the turbo pushing 10cfm. So to get 7psi at the TB the 20cfm may have to actually make 7psi, while the 10cfm may need to make 8psi to make up for it.

I'm pretty sure the rearrangment of this is what you're arguing: that if both are "working as hard" the larger turbo will push more air into the TB. And more air being pushed into a fixed space = more pressure(more boost).

Hence why I argue that when measured at the TB boost is boost. It's simply a volume of air being pushed into a fixed space. It doesn't matter what's pushing it.

Bill

Hey, you could try!...but yeah, more than likley wouldn't work.

Suprise suprise, they put the 22RE in a Celica for 1 year and someone comes out with a supercharger. They keep it in trucks for 10 years and no one knows squat!

dcg9381

I'm running a mid-compression motor w/o an intercooler. I'll add an intercooler as soon as I start seeing intake temps higher than 170.

The normal intake temps on the 22re (at 70 degrees ambient) are about 125 degrees in the manifold, btw..

For small turbos, 3-4 psi, I doubt you're generating enough heat to justify adding the complication and cost of an intercooler. I don't particularly recommend them on the 22RTE either, due to low boost.. Past 8-9 psi, I'd certainly consider one.

mastacox

The point several people are trying to make is that for a given engine speed and a given psi, you have a SET amount of air flowing into your engine (displacement*rpm). Having a bigger turbo means you will be able to push a given psi at higher engine speeds; but the fact remains that if a turbo is pushing 7psi it only matters how much air the engine is taking in, not how much the turbo can put out. Now if the engine is trying to take in more air than the turbo can supply at that pressure, then your pressure will drop.

^VooDoo^

Mastacox, I agree with that.

smar06

Hey sonofmayhem. How did you make out with all your wiring & vacuum line problems from last week. I'm assuming and hoping your truck is running great.

Sonofmayhem

My dad is paying to get it fixed by a pro i wanted to pay it but he offered so i cant turn that down it was running but throwing 6 codes, then 3 so its getting a complete wiring harness. i cant wait. im collecting parts.

Smiling_Jim

I learned playing with those toys that most stock NA engines will easily take 7lbs of boost (1/2 atmosphere) and yield an approximate 50% HP increase.

I have not worked on the engine internals yet in my 22RE Crawler. It seems from the above commentary that the 22RE needs custom 7.5:1 CR pistons and some combustion chamber mods in order to yield more boost. More flexible fuel and ignition management is a given.

DCG getting high bottom end torque and moderate hp gains seems backwards from what my crawler needs. It needs torque and HP from 3k to 5k rpms for highway driving and sand dunes. I would prefer no boost at WOT until at least 2500 rpm, and then a steady increase to 7psi at 5k rpm.

It should be possible, with a larger turbine housing and proper waste gate setup to design a system that would give the 22RE power where it needs it, at mid range to high rpm.

Any thoughts from the collective on this? From what I have read so far, I wouldn't bother putting a turbo on a 22RE.

dcg9381

Jim, the efficiencies of head designs as well as ignition systems have improved dramatically over the last 20+ years. Remember, the 22R series was probably designed back in the 1970s.

I agree that some late model cars seem to handle significant boost very well and can produce big power safely. I don't think the 22R series is one of them due to factors like compression, ignition timing, and EFI system.


The least expensive way to lower the compression on the 22RE is to use 22RTE pistons. With a 22RE head, the net compression will be close to 8:1.

Jim, I'm in TX so we don't see a lot of dunes. Especially for trucks without dual transfer cases, a boost in low end torque is very helpful, especially in the "drivable" RPM range.

I understand the need for HP in dunes.

Check my website, there are a few dyno runs. You'll see one with a GT28R turbo (small, ball bearing) - it has a great curve with an increase in both HP and torque across the board, but following the same torque band of a typical 22RE - decreasing after about 4500-4700. Just remember that a stock 22RE dynos around 80-86 at the rear wheels when you look at the graphs.

In regard to your request:
A larger compressor certainly will make that happen. I was running a t3/t04b, which really is too big for the 22R series. It would start to boost around 1800-2k and produce 7psi at 3k. Intake temps were very low for a turbo, about 40-50 degrees above what you'd see in an NA setup. No need for an intercooler. You might find boost down low useful, I'm dumping that turbo for something a little smaller - but you're right, a larger compressor will do what you want it to do.
The other alternative is an electronic boost controller, which can help manipulate the wastegate.


Personally, I've found it very "worth" it to put a turbo on a properly modified 22re. You're talking about an engine that can put down 100% more power and torque (on a dyno) than a stock motor and still get near stock MPG. If I do it again, I'd try to do it in a "budget" config with 22RTE internals.
My 4runner is SOO much more drivable on the highway with that sort of power. 70-80mph at 1/4 throttle instead of 3/4... If you've got a truely geared down crawler/trail rig, I understand why it might not be worth the hassle.