**CHALLENGE** - TURBO LAG TEST using a log

[dmaxbowtie]

I'll try to look through my logs tonight and see how the 366 did

 

[coker6303]

he has a good point Russ, i do like your test though! brian, sean and i were jsut talking about testing this with others yesterday.

Here is my feed back on my stock turbo over my s475 with batmowheel/Yellowchevy upgrade.

At 60mph, 5th gear TC locked, 1500rpm, no load and without letting it down shift, i can hit 20psi at just over a second but its also building 1-2psi of boost before rolling into the throttle. its hard to be "out of boost" so to speak on my setup.

ill see if i can get a log now but i just swapped to 4.56 gears so its REALLY hard to get it out of boost now. i was almost borderlined before due to the longer time between shifts



This whole test your doing is something i was trying to figure out a long while back before i did twins. i finally got Andrew on here to do a loaded test with his truck (bascially the same as mine but with 35s and triple turbos with a 366 as the high pressure). under the same circumstances as i said above but loaded, he could not get boost to build until 1800 rpm. that right there answered my question on whether or not id ever jump up in charger size (i wont).

My turbo setup doesn't really come on hot until 1800rpm when cruising in lockup. For my use I would have been happier with the stock/475 setup for sure, but hindsight is 20/20.

I'll try to get a log from a locked roll in 5th at 1500rpm today.

Maybe we should make a list with turbo(s), converter and then time result of both test so a chart of the different combo's can be somewhat usable for those looking at upgrading.

 

[Chevy1925]

That would be great if we get enough true info

 

[chevyburnout1]

I think from a dead stop mine doesn't hit 20 pounds of boost until half way through second gear :rofl:

 

[quinton]

Ill do mine in a minute. Idk how to get a log on here though.

 

[quinton]

Mine shows to be 1.98 seconds. From 14.8-35.2.

 

[quinton]

 

[quinton]

And this is from a 60 mph roll, no downshift tow haul on. 1.26 seconds.

 

[MACKIN]

I use to do that test that Iowa suggests all the time .

1) I had the cops at my house something about a road rage incident!
2) That was back when smoking was cool!
3) :roflmao:

 

[JoshH]

Mine shows to be 1.98 seconds. From 14.8-35.2.

Why did you start your highlighting at 1631 RPM?

And this is from a 60 mph roll, no downshift tow haul on. 1.26 seconds.

Are you in 4th gear here? 2385 RPM at 60 MPH?

 

[quinton]

Why did you start your highlighting at 1631 RPM?



Are you in 4th gear here? 2385 RPM at 60 MPH?

Missed the first part. Didn't look at rpms was watching MAP. I was going off of what boost was reading. It was a steady 14.8 until I hit the throttle.

Might have been in 4th. I thought I was in 5th. Tow haul was on and it didn't down shift.

 

[Harbin_22]

For my use I would have been happier with the stock/475 setup for sure, but hindsight is 20/20.

We can make that happen. Trade plus some cash???

 

[coker6303]

We can make that happen. Trade plus some cash???

If I didn't have bad memories from my install (broke nose/eyebrow, loss of vision and ruptured blood vessel behind my eye...) if be all over it! Lol. Maybe when the turbos come off for an engine build I'll swap, yours would definitely be a better setup for me to daily drive.

I'm jealous of your built motor!!

 

[matt78]

Whats wrong with yours russ? I pull a 5th wheel with my setup

 

[coker6303]

Whats wrong with yours russ? I pull a 5th wheel with my setup

Pulling, mine is great! EGT's are cool and she pulls like a beast once you are rolling with a little heat in the turbos. Very happy with the towing side.

It's the normal, in and out of traffic that I would like something a bit more responsive. The lag isn't horrible, but it's definitely noticeable.

I drive everyday in Houston traffic, and tend to be a bit aggressive. I've ridden in my cousins stock/475 combo that Josh tuned and it is night and day more responsive than my 66/80 setup. I know I would have been happier with that setup, without a doubt. But...that doesn't keep me from thrashing on ol' betsy like she is!! lol




Traffic is horrible right now in Houston or I would have my log from a 1500rpm roll in 5th. If I don't get it tonight, I'll get it tomorrow on the 2hr drive back home.

 

[coker6303]

What's the time if you back the spread up to where the rpm's jump? or if you have the TPS on there, when you pin it?

 

[quinton]

Give me a little while and I'll look. I was in a hurry when doing this earlier. I would guess in the mid 2 second area.

 

[Chevy1925]

Well I tried logging on the way home but the computer died.

The gears made a noticeable difference. Feels like a truck in stock tires again lol. There's like no lag in this bitch anymore and I can roll into the throttle way harder in 5th gear, TC locked and 1500rpm. There is no counting when I can hit 20psi, it's damn near instant.

I'll get a log Thursday after my new intercooler from mishimoto goes in (yay no more boost leaks!)

 

[coker6303]

My TCM file wasn't right, so I couldn't stomp it wot but I was able to give it enough throttle to have a good log.

4.72sec from a 1500rpm roll to 20psi boost locked in 5th

 

[coker6303]

Don't cheat when you do this, look at your cruising throttle percentage and start the range accurately.

My results summarized - time to hit 20psi above MAP

T4 S366 over T6 S480 both standard cast wheels
tires - 305/50r20
air temp - 45F
elevation - 270'

from a standstill 3.57sec
from a 1500rpm roll 4.72sec