Speed-Talk is running on www.Speed-Talk.com

IMPORTANT: Update your bookmarks to https://www.speed-talk.com/forum/
(Right-click the URL and select "Bookmark this link")

Search found 591 matches

by RednGold86Z
Wed May 05, 2021 1:00 pm
Forum: Engine Tech
Topic: EFI Fuel Pressure Drop ~5psi
Replies: 20
Views: 610

Re: EFI Fuel Pressure Drop ~5psi

Are you running a dead-headed line to the front from the rear regulator? That will cause the pressure drop, especially if you also have a fuel filter that is getting clogged. If you're running pump -> filter -> injection -> regulator -> return to tank, then you wouldn't have this problem unless the ...
by RednGold86Z
Mon May 03, 2021 7:06 pm
Forum: Engine Tech
Topic: EFI Fuel Pressure Drop ~5psi
Replies: 20
Views: 610

Re: EFI Fuel Pressure Drop ~5psi

Where is the pressure read & regulated? Read at the TBI, regulated about 14ft away at the fuel tank This is your problem. Not a big problem if it's fully closed loop AFR control, and if the injectors are a bit larger than necessary. If you were to read it at the regulator, it would likely be consta...
by RednGold86Z
Tue Jun 25, 2019 6:36 pm
Forum: Engine Tech
Topic: EGT and 02 sensors
Replies: 48
Views: 3664

Re: EGT and 02 sensors

Widebands (that I use) have sensor element temperature readings but are heated to a specific temperature by the controller, so I doubt it's very good at reading EGT. I've only used EGT *tuning* to ensure exhaust valve longevity. When fuel economy or emissions matter, stoich may need to be used at co...
by RednGold86Z
Mon Dec 03, 2018 5:07 pm
Forum: Engine Tech
Topic: EFI for big inch BBC
Replies: 30
Views: 3463

Re: EFI for big inch BBC

I'm installing FItech six pack this week on a 71 challenger 440...original 6 pack car. It's the first one FITech built, according to them...so we are the guinea pigs on this deal. I'm interested on how it will progressively bring in the outboard throttle bodies...which they told me it will Who told...
by RednGold86Z
Mon Dec 03, 2018 4:25 am
Forum: Engine Tech
Topic: EFI for big inch BBC
Replies: 30
Views: 3463

Re: EFI for big inch BBC

I'm installing FItech six pack this week on a 71 challenger 440...original 6 pack car. It's the first one FITech built, according to them...so we are the guinea pigs on this deal. I'm interested on how it will progressively bring in the outboard throttle bodies...which they told me it will Who told...
by RednGold86Z
Wed Nov 28, 2018 1:09 am
Forum: Engine Tech
Topic: EFI for big inch BBC
Replies: 30
Views: 3463

Re: EFI for big inch BBC

If you do go FiTech, I often look at the control software and calibration engineer in the mirror, and sleep with his wife :mrgreen:
by RednGold86Z
Thu Apr 26, 2018 4:45 am
Forum: Engine Tech
Topic: anyone experience this effect of injecting on intake stroke ?
Replies: 62
Views: 6652

Re: anyone experience this effect of injecting on intake stroke ?

The fuel must travel from the injector to the valve this takes time. Transport delay. It's not a constant either. But it's not far from a constant amount of time. It's coming out of the injector with the same fuel pressure, into, give-or-take, the same air speed, but just some varying density. The ...
by RednGold86Z
Tue Apr 17, 2018 9:10 pm
Forum: Engine Tech
Topic: anyone experience this effect of injecting on intake stroke ?
Replies: 62
Views: 6652

Re: anyone experience this effect of injecting on intake stroke ?

On our small OEM engines that I did a few years ago, low RPM and low load injection on the open valve had much worse engine out emissions and rougher running. Idle was much rougher. I believe the logic is the hot valve aids evaporation, and the residual cylinder pressure right at IVO blasts fuel up ...
by RednGold86Z
Fri May 05, 2017 11:45 am
Forum: Engine Tech
Topic: 1987 camaro tpi tuning advise
Replies: 9
Views: 1687

Re: 1987 camaro tpi tuning advise

http://www.moates.net APU1 Autoprom. G1 adapter. Tunerpro RT. And study study study. It's a MAF system, so, you're not going to need to do much. Mostly, set the timing - need to disconnect the EST enable wire from the distributor and put timing at about 6 degrees (computer will advance from there a...
by RednGold86Z
Thu Feb 09, 2017 7:08 pm
Forum: Engine Tech
Topic: Pulsing fuel injectors when dry
Replies: 2
Views: 730

Re: Pulsing fuel injectors when dry

I don't recommend running them dry. I've locked some up when dry running them for too long. If you want, just take the end caps off and disconnect the injectors. The end caps have 2 O-rings per side to seal the fuel crossovers, so don't lose those. Also use a little lube when reassembling, and make ...
by RednGold86Z
Wed Jan 18, 2017 2:59 pm
Forum: Engine Tech
Topic: holley sniper question
Replies: 5
Views: 1459

Re: holley sniper question

Here is my question? Is the FiTech 1200HP 8 injector unit you are running a two separate 4 port throttle bodies each with 4 injectors? My reason for asking is if this is a normally aspirated engine, the largest single throttle body they appear to offer is only about 850 cfm and you can't make 1200H...
by RednGold86Z
Fri Dec 02, 2016 11:03 am
Forum: Engine Tech
Topic: Why does GM spec such low idle timing advance?
Replies: 21
Views: 3283

Re: Why does GM spec such low idle timing advance?

But where it gets more interesting (to me at least) is that GM is STILL recommending the same thing on their current crate engines that are not emissions compliant: ZZ427 (480 hp): 10-12 dgr ZZ572 (620 hp): 15 dgr Both of the crate motors state "The HEI vacuum advance canister should remain disconn...
by RednGold86Z
Mon Nov 28, 2016 5:56 am
Forum: Engine Tech
Topic: engine idles great cold but poorly when warm question
Replies: 13
Views: 2328

Re: engine idles great cold but poorly when warm question

That's what a vacuum gauge is for. Use it to get best vacuum at idle while adjusting AFR and timing. Nothing else required. If you did that, you'd end up typically too rich and "too much" timing. With a properly set up EFI with wideband AFR control, with timing control and idle control, you can usu...
by RednGold86Z
Mon Nov 28, 2016 1:51 am
Forum: Engine Tech
Topic: engine idles great cold but poorly when warm question
Replies: 13
Views: 2328

Re: engine idles great cold but poorly when warm question

What is your Idle Target RPM? Huge cams may need over 1200+, while a stock ish cam can handle 650. Adjust (open = counter clockwise) the throttle screw to get the warm IAC steps to basically 0 (more open screw results in lower IAC steps). With automatics, I often cheat, and when in park i have it at...
by RednGold86Z
Tue Sep 27, 2016 1:55 am
Forum: Engine Tech
Topic: decel question
Replies: 46
Views: 5877

Re: decel question

As RednGold86Z said it's the fuel puddle evaporating. Your best options are either tuning the EAE or leaning out the cells on the VE table that you spend in decel but not under power or in cruise. The problem the latter creates is you won't have enough acceleration enrichment to make up for the lac...