Boost difference. Dyno VS Street - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

eLeSthree · 12-13-2019, 06:07 AM

I recently dropped a pulley size from 100mm to 95mm.
(sorry, ESS uses metric. 100mm is 3.93, 95mm is 3.74)

On the dyno the 100mm made peak boost of 18.7 @6800 rpms
On the street the 95mm made peak boost of 18.4 @ 6800 rpms
I havent retuned for the 95mm, so it hasnt seen the dyno. (FP drop problems)

I cant find a log of the 100mm on the street, but this should prove that I see less boost on the street than I do at the dyno.

I've heard people usually see MORE boost on the street than the dyno. Is this normal?

I'm dropping down to a 90mm (3.5) as soon as my fuel pump assembly arrives. I'd like to get closer to 900whp but that wont happen if I cant up the boost...

Is it possible that my K&N air filter is a restriction? I've cleaned it and it doesnt see many miles, but it does appear to be collapsing a little. I picked up an Airaid Race Day filter to see if that helps. It has no paper element, its just a screen basically. Not meant to drive on the street, but it will keep out small rocks and birds and shit.

RealQuick · 12-13-2019, 06:25 AM

What was the air temp differences between the two different runs (iat’s).

eLeSthree · 12-13-2019, 06:48 AM

Quote:

Originally Posted by RealQuick

What was the air temp differences between the two different runs (iat’s).

13 degrees. It's listed above in white.

eLeSthree · 12-13-2019, 06:51 AM

Just realized, the dyno was in 4th, street was in 3rd. Will that make a difference?

stevieturbo · 12-14-2019, 01:57 PM

On a blower car....I wouldnt really expect there to be much change either way.

On a turbo car, load can change things a fair bit, and also ambient/charge temps perhaps more so than a blower.

The difference you're showing on your graph of 228 vs 231kpa, really is nothing. The lower value is also at almost 80rpm less at the engine

Either way.....you need bigger injectors or a fuel system upgrade from those graphs.

eLeSthree · 12-16-2019, 05:57 AM

Quote:

Originally Posted by stevieturbo

On a blower car....I wouldnt really expect there to be much change either way.

On a turbo car, load can change things a fair bit, and also ambient/charge temps perhaps more so than a blower.

The difference you're showing on your graph of 228 vs 231kpa, really is nothing. The lower value is also at almost 80rpm less at the engine

Either way.....you need bigger injectors or a fuel system upgrade from those graphs.

Yes sir. Triples on the way.

The difference in the logs is minimal, yes, but it should be larger since one is running a much smaller pulley.

acammer · 12-16-2019, 07:54 AM

Quote:

Originally Posted by stevieturbo

On a blower car....I wouldnt really expect there to be much change either way.

On a turbo car, load can change things a fair bit, and also ambient/charge temps perhaps more so than a blower.

The difference you're showing on your graph of 228 vs 231kpa, really is nothing. The lower value is also at almost 80rpm less at the engine

Either way.....you need bigger injectors or a fuel system upgrade from those graphs.

That was the first thing I saw rpm/IDC/AFR headed in one direction, and fuel pressure headed the other way.

The boost difference is pretty marginal. It might get air a little better on the dyno with the hood up, and make a tick more. The rate of acceleration may have been a little different as well - I wouldn't think that would matter much to a centrifugal - but you're not talking about much of a difference. I wouldn't be bothered by that.

But the fuel pressure and IDC - it's time for more pump!

eLeSthree · 12-16-2019, 10:16 AM

Quote:

Originally Posted by acammer

That was the first thing I saw rpm/IDC/AFR headed in one direction, and fuel pressure headed the other way.

The boost difference is pretty marginal. It might get air a little better on the dyno with the hood up, and make a tick more. The rate of acceleration may have been a little different as well - I wouldn't think that would matter much to a centrifugal - but you're not talking about much of a difference. I wouldn't be bothered by that.

But the fuel pressure and IDC - it's time for more pump!

For sure. even with 1300cc injectors...
Just plumbed an entire new fuel system.
https://www.camaro5.com/forums/showt...=564168&page=2
Working with DSX to test their new In-tank triple pump assembly. It should arrive tomorrow, as it was on display at PRI this weekend.

My concern with the boost.. I dropped a pulley size (3.93 - 3.74) and did not see an increase in peak boost. Hoping the filter was the restriction as I plan to drop to a 3.5 pulley.

Bildo · 12-20-2019, 03:27 PM

I have a seen up to a 90 rwhp difference between the intake tube and filter on my F1A and no intake tube or filter.

12-13-2019, 06:07 AM	#1
eLeSthree Drives: 2011 Camaro SS 6sp Join Date: Nov 2016 Location: Drivers Seat Posts: 1,904	Boost difference. Dyno VS Street I recently dropped a pulley size from 100mm to 95mm. (sorry, ESS uses metric. 100mm is 3.93, 95mm is 3.74) On the dyno the 100mm made peak boost of 18.7 @6800 rpms On the street the 95mm made peak boost of 18.4 @ 6800 rpms I havent retuned for the 95mm, so it hasnt seen the dyno. (FP drop problems) I cant find a log of the 100mm on the street, but this should prove that I see less boost on the street than I do at the dyno. I've heard people usually see MORE boost on the street than the dyno. Is this normal? I'm dropping down to a 90mm (3.5) as soon as my fuel pump assembly arrives. I'd like to get closer to 900whp but that wont happen if I cant up the boost... Is it possible that my K&N air filter is a restriction? I've cleaned it and it doesnt see many miles, but it does appear to be collapsing a little. I picked up an Airaid Race Day filter to see if that helps. It has no paper element, its just a screen basically. Not meant to drive on the street, but it will keep out small rocks and birds and shit. Attached Images __________________ 2011 Camaro SS---SOLD TMS Dart 427 FED M311s, ESS Tuning G4 Blower, DSX Triple FP Assembly, DSX FF, FIC1300, Mcleod RXT 1200HD, Edlebrock Pro Flo XT 1158whp 1017wtq. 2010 CTS-V A6 - "Stock" SOLD 630whp 658wtq 2024 F-150 RCSB 5.0 4x4 waiting for tunes...

12-13-2019, 06:51 AM	#4
eLeSthree Drives: 2011 Camaro SS 6sp Join Date: Nov 2016 Location: Drivers Seat Posts: 1,904	Just realized, the dyno was in 4th, street was in 3rd. Will that make a difference? __________________ 2011 Camaro SS---SOLD TMS Dart 427 FED M311s, ESS Tuning G4 Blower, DSX Triple FP Assembly, DSX FF, FIC1300, Mcleod RXT 1200HD, Edlebrock Pro Flo XT 1158whp 1017wtq. 2010 CTS-V A6 - "Stock" SOLD 630whp 658wtq 2024 F-150 RCSB 5.0 4x4 waiting for tunes...

12-20-2019, 03:27 PM	#9
Bildo Drives: 2012 2SS/RS LS3 Join Date: Dec 2011 Location: Omaha, Nebraska Posts: 1,677	I have a seen up to a 90 rwhp difference between the intake tube and filter on my F1A and no intake tube or filter. __________________ 2012 2SS M6, ERL Superdeck 6 427, PRC 255 Heads, Procharger F1A w/ 3.85 pulley, 1300hp intercooler, Squash Dual 450lph, E85, ID1700, RXT Clutch, DSS 1pc driveshaft, GForce axles, Eaton Detroit Trutrac, a bunch of other crap I don't feel like typing.

12-13-2019, 06:25 AM	#2
RealQuick Drives: 2010 Camaro 2SS M6 - Intake/Exhaust Join Date: Sep 2014 Location: Bridgewater Posts: 693	What was the air temp differences between the two different runs (iat’s).

12-14-2019, 01:57 PM	#5
stevieturbo Drives: it changes Join Date: Nov 2010 Location: Norn Iron Posts: 1,126	On a blower car....I wouldnt really expect there to be much change either way. On a turbo car, load can change things a fair bit, and also ambient/charge temps perhaps more so than a blower. The difference you're showing on your graph of 228 vs 231kpa, really is nothing. The lower value is also at almost 80rpm less at the engine Either way.....you need bigger injectors or a fuel system upgrade from those graphs.