I hear you guys, i just hate the look of the EFI manifold. Also my fuel milage is not the greatest either. Ive got it to the best milage right now at about 18 mpg without running AC despite being in south texas. But thanks for answering my question. It gives me more to consider before i pull the plug on the EFI.
I agree with the "look" and wires everywhere. That's why I did it, but my assumptions about the factory engineering were way off. The EFI was carefully engineered for this engine, and for a daily driver no other combo will match the drivability/ response/ economy. Here this again: an Offy intake and 4V carb are way short of the response and power of the stock EFI.- and never mind the extra 35% of gas used for every mile driven. They're gaudy, but those individual 19" runners are near ideal, and can not be duplicated in any way whatsoever with any carb intake.
 
I agree with the "look" and wires everywhere. That's why I did it, but my assumptions about the factory engineering were way off. The EFI was carefully engineered for this engine, and for a daily driver no other combo will match the drivability/ response/ economy. Here this again: an Offy intake and 4V carb are way short of the response and power of the stock EFI.- and never mind the extra 35% of gas used for every mile driven. They're gaudy, but those individual 19" runners are near ideal, and can not be duplicated in any way whatsoever with any carb intake.
I was planning on using my aussie speed intake with a 2v carb. I had gotten it for a different project but had to buy another truck for work before continuing on with the project. And now im considering giving up the first truck since the truck i got for work is exactly what i want. Plus with the carb cheater thats now out there by thunderhead 289, im wondering if that device would make carbs just as good as EFI.
 
I was planning on using my aussie speed intake with a 2v carb. I had gotten it for a different project but had to buy another truck for work before continuing on with the project. And now im considering giving up the first truck since the truck i got for work is exactly what i want. Plus with the carb cheater thats now out there by thunderhead 289, im wondering if that device would make carbs just as good as EFI.
I hear ya Dave. Forget the carb cheater. Put the Aussi on there, ok. (Will it fit with AC?) Part of my dissatisfaction has always been the ignition system. If you can keep the TFI ignition, it may do real well with the carb- I for one would be very interested in the results.

Recap: used a Summit HEI dizzy when the swap to Offy DP/Edelbrock500, until this year. Despite countless tweaks with springs, weights, vacuum advance timing was never exactly right. Now have a DS2 that Bill Amber curved for the EFI head. (And a Holley 390) It's way better, mileage is up slightly, but - hear this- the EFI head is ultra sensitive to timing AND that timing is highly affected by engine temperature. The current ignition is almost right- until the engine gets over 185*, then it pings. The factory timing table pulls eight degrees of timing at 195* from 180*. Without a knock sensor, there is NO WAY to keep the EFI head at ideal timing. So carbing it and keeping the TFI computer ignition may give good results.

If you are truly shooting for max economy, I'll challenge you to try this, I will wager it improves economy: Change the 195* thermostat for a 180*. I am not exaggerating the exceptional economy of this truck with EFI. Flat, hot area like you're in. It got 22-24 mpg @ 60 mph AC on. E4 auto trans/ 3.08 gear. Repeatedly, on a monthly trip to Charleston, 75 miles. Went there and back on about 6 gallons of gas. It has a 180* stat. @ 180* the computer is running earlier timing than at higher temps. If it's too much, the KS catches it. This way the timing is always at max efficiency. @ 195* the computer may be leaving some some tune on the table with the 8* retarded spark.
 
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Ok, new questions as im starting to pick up another build. I got a buddy who wants efi for his 300 and i got a spare harness and computer and all. However Im wanting to do a bump in power and i heard the moates QH is discontinued. Is there something similar in the market or would i need to get a mega squirt? Or should i just sell him on getting a self tuning efi like a sniper even tho i believe for the 300 mpfi is better.
 
The Holley Terminator X or the Holley HP is also an option for MPFI.
This is what my first thought was as well when I read the post and it mentioned the Holley Sniper as an option. For similar pricing as a Sniper, I'd consider the Terminator X and HP for their port injection, sequential injection, and sequential spark opportunities, as well as expansion options I don't know that Sniper can do.
 
CoreTuning.net still sells the quarterhorse but you have to buy a binary editor license as well. Takes the price up a couple hundred bucks.

 
CoreTuning.net still sells the quarterhorse but you have to buy a binary editor license as well. Takes the price up a couple hundred bucks.

Ok, so based on the website since my 300 is an obd1 i would get the quarter horrse package for $500. Thats not too bad if i can tune this project and my own truck if i decide to stick with efi. Also ive been hearing while the carb cheater is a good product, its still not better than efi.
 
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