Smaller turbo now have flat spot? - Competition Diesel.Com

muz · 07-16-2019, 07:02 PM

I've had a 62/71/14 turbo with 5x14 injectors with 10 thou pintle lift on my truck for a long while but its always been a little smokey with a little lag. I've changed the turbo for a 62/65/12 and now it pulls well hits a flat spot (almost like a rev limiter) then powers on again do you think this is a drive pressure issue?

jasonc · 07-17-2019, 05:51 AM

Do you hear any surge when this happens?

muz · 07-17-2019, 09:17 AM

no real surge it just goes flat for what seems like a few seconds then it powers on again

CorneliusRox · 07-17-2019, 09:32 AM

Seems like an AFC or Gov Spring issue to me.

Is it purely RPM based, or purely boost pressure based?

jasonc · 07-17-2019, 10:36 AM

Check or tighten your gate.

07-16-2019, 07:02 PM	#1
muz Name: muz Title: Diesel Enthusiast Status: Not Here Join Date: Feb 2009 Location: Hampshire U.K Member`s Gallery Posts: 174	Smaller turbo now have flat spot? I've had a 62/71/14 turbo with 5x14 injectors with 10 thou pintle lift on my truck for a long while but its always been a little smokey with a little lag. I've changed the turbo for a 62/65/12 and now it pulls well hits a flat spot (almost like a rev limiter) then powers on again do you think this is a drive pressure issue? __________________ 97 x-cab LB 4x4 goerend, DHD, gsk, #10 plate, gauges, 05 rims, 4" pipe AFE, II 62/71/14, ARP studs, fluidampr, 5x14's, mack plug... Last edited by muz; 07-16-2019 at 07:09 PM.

07-17-2019, 09:17 AM	#3
muz Name: muz Title: Diesel Enthusiast Status: Not Here Join Date: Feb 2009 Location: Hampshire U.K Member`s Gallery Posts: 174	no real surge it just goes flat for what seems like a few seconds then it powers on again __________________ 97 x-cab LB 4x4 goerend, DHD, gsk, #10 plate, gauges, 05 rims, 4" pipe AFE, II 62/71/14, ARP studs, fluidampr, 5x14's, mack plug...

07-17-2019, 09:32 AM	#4
CorneliusRox Name: CorneliusRox Title: Seasoned Rookie Status: Not Here Join Date: Dec 2012 Location: Detroit, MI Member`s Gallery Posts: 4,154	Seems like an AFC or Gov Spring issue to me. Is it purely RPM based, or purely boost pressure based? __________________ Corey - BSME '21 Tesla Model 3 Perf '22 DMax AT4 2500

07-17-2019, 05:51 AM	#2
jasonc Name: jasonc Title: Too Much Time Status: Not Here Join Date: Nov 2009 Member`s Gallery Posts: 4,412	Do you hear any surge when this happens?

07-17-2019, 10:36 AM	#5
jasonc Name: jasonc Title: Too Much Time Status: Not Here Join Date: Nov 2009 Member`s Gallery Posts: 4,412	Check or tighten your gate.