400FWHP TBI build attempt thread

**Fast355** · 12-23-2016

Personally I wpuld run the big block injectors at that power level. I have run the 61s as high as 50 psi but the opening and closing times start to get too long for higher rpm use.

**Gojira94** · 12-24-2016

Originally Posted by Fast355

Personally I wpuld run the big block injectors at that power level. I have run the 61s as high as 50 psi but the opening and closing times start to get too long for higher rpm use.

Thanks for the input. When you say higher RPMs, how high? I'm planning to spin no higher than 5500, limiter set at 5750. I'm feeling like I should have insisted on BBC injectors. I think I'd have fewer concerns and questions.

**Fast355** · 12-25-2016

Originally Posted by Gojira94

Thanks for the input. When you say higher RPMs, how high? I'm planning to spin no higher than 5500, limiter set at 5750. I'm feeling like I should have insisted on BBC injectors. I think I'd have fewer concerns and questions.

You are going to have a hard time making 400 hp under 6,000 rpm on a 350 that mild.Pulsewidth to stay under 80% duty cycle goes from 5msec at 5,000 to 4 msec at 6,000. If it takes 500 usec to open the injector and another 250 usec to close you are looking at needing an injector that can get the fuel volume necessary in 3.25 msec. Big injectors are a must for a high hp TBI.

**dave w** · 12-25-2016

Originally Posted by Fast355

You are going to have a hard time making 400 hp under 6,000 rpm on a 350 that mild.Pulsewidth to stay under 80% duty cycle goes from 5msec at 5,000 to 4 msec at 6,000. If it takes 500 usec to open the injector and another 250 usec to close you are looking at needing an injector that can get the fuel volume necessary in 3.25 msec. Big injectors are a must for a high hp TBI.

I agree with Fast355 on the using Big injectors to make 400 hp. My own personal best with a SBC 5.7 Liter TBI chassis dyno pull was 330 Rear Wheel HP using 454 TBI injectors part #5235231 at 15 PSI. I used Vortec heads, EFI roller camshaft (similar to a Comp Cams 268 grind), Vortec 4 barrel aftermarket intake with a TBI adapter plate, headers, 9.2:1 CR, 0.045" Quench, and the 16197427 PCM... I admit there was a slight trade off in the tune, the big injectors were on the rich side at idle at 15 psi... The 16197427 has near idle fuel and spark tables, very helpful for idle tuning! The 16197427 has off idle fuel and spark tables, very helpful for MAX performance tuning! ... The EBL system does not have separate near idle / off idle fuel and spark tables, I wish it did... dave w

**Fast355** · 12-27-2016

Originally Posted by dave w

I agree with Fast355 on the using Big injectors to make 400 hp. My own personal best with a SBC 5.7 Liter TBI chassis dyno pull was 330 Rear Wheel HP using 454 TBI injectors part #5235231 at 15 PSI. I used Vortec heads, EFI roller camshaft (similar to a Comp Cams 268 grind), Vortec 4 barrel aftermarket intake with a TBI adapter plate, headers, 9.2:1 CR, 0.045" Quench, and the 16197427 PCM... I admit there was a slight trade off in the tune, the big injectors were on the rich side at idle at 15 psi... The 16197427 has near idle fuel and spark tables, very helpful for idle tuning! The 16197427 has off idle fuel and spark tables, very helpful for MAX performance tuning! ... The EBL system does not have separate near idle / off idle fuel and spark tables, I wish it did... dave w

I have never once used seperate VE table or Spark values at idle. I found them an annoyance. Even on my 0411 both idle tables and the main table have the same values.

**dave w** · 12-27-2016

Originally Posted by Fast355

I have never once used seperate VE table or Spark values at idle. I found them an annoyance. Even on my 0411 both idle tables and the main table have the same values.

I completely agree, separate VE and Spark tables are an annoyance. I was very annoyed with the hours and hours of time I spent writing an excel spreadsheet that would sort / filter / average the separate tables from the data log .csv file. I also find waiting on the spreadsheet to finish processing annoying. dave w

**Gojira94** · 12-27-2016

Originally Posted by Fast355

You are going to have a hard time making 400 hp under 6,000 rpm on a 350 that mild.Pulsewidth to stay under 80% duty cycle goes from 5msec at 5,000 to 4 msec at 6,000. If it takes 500 usec to open the injector and another 250 usec to close you are looking at needing an injector that can get the fuel volume necessary in 3.25 msec. Big injectors are a must for a high hp TBI.

Thanks- that's the math I needed to know that I need to learn. I'll touch base with Sean at SPR and swap out injectors. I may not hit 400FW but it'll come pretty damn close by 5700 if nothing scatters. I've studied and planned this build for 6 months. Fueling and tuning are the 2 biggest variables for success with my build and I know it. I had wanted to keep the stock TBI intake and open the bores but I'm headed toward the Holley 300-49 since it doesn't need to be bored to accept a 46mm TB and it has the center bolt holes at the correct angle for the early pattern SBC heads I'm using. Slotting the stock TBI centers was starting to look ugly for lack of room there without hitting the walls.

**Gojira94** · 12-27-2016

Right now I'm looking at how to resolve the code 23 it's throwing in EBL, on a truck with no IAT/MAT sensor. The word/ bit aren't set for that in the base bin (ebl_f_2010) and I'm not sure why I'm getting it. I wanted to square everything away and fine tune the stock setup for practice VE learns, etc. before tearing into it. Hoping to start tearing it down later this week.

**Gojira94** · 12-28-2016

I reflashed banks 0 and 1 with the 2010 and 2011 bins. Now each one works and drives normally and the SES light isn't on, but I see this in the Malf Codes display. The screen cap doesn't show it, but the IAT LO 23 blinks in the first column and is solid in the 3rd. The EST code 42 is just solid in the 3rd column. That's knock sensor failure and it's defaulting to the ICM control of timing in the distributor, correct? I think my question is about how to read this malfunction code table in EBL.

**Gojira94** · 12-29-2016

I disconnected the battery for a few minutes and tried again. This time I only got the code 23 blinking in the first column. I read somewhere recently that it's normal for it to do that. No other codes in any column. It drives really well. Very happy with how it runs on the EBL in stock form. If anyone more familiar with EBL Flash than me can briefly explain what the 3 Malf Code table columns are about I'd appreciate it.