Don Terrill’s Speed-Talk

That Elgin 224 cam at 9.78 (18cc) will make a great truck cam, with a nice idle. Might hit 430-440hp. Not far from the Blueprint 415hp 383 that I had, but with a bigger but wider LSA cam and slightly better heads and 10:1 cr. Perfect for a 2100 RPM stall 4l80e. You could go tighter LSA - down to 110...

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 ...

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 co...

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...

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...

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...

If you do go FiTech, I often look at the control software and calibration engineer in the mirror, and sleep with his wife

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 ...

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 ...

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...

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 ...

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...

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 di...

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, y...

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...