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400hp 351w startup tune

Posted: 2022 Dec 18, 11:41
by efloth
Do any of you have a good startup tune with the expanded VE table and 80 lb injectors? I'm getting closer to you installing my engine and am hoping that I don't have to do major tuning work while trying to break it in correctly.

Re: 400hp 351w startup tune

Posted: 2023 Jan 07, 01:47
by decipha
this should get you started at least

remember to run 30psi base fuel pressure

Re: 400hp 351w startup tune

Posted: 2023 Jan 09, 00:01
by efloth
Thank you sir! I was planning on running a stock regulator. What is the benefit of lower fuel pressure? Better control?

Re: 400hp 351w startup tune

Posted: 2023 Jan 09, 13:21
by decipha
the 80s are linear at 30psi.

you can run any pressure you desire just dial her in

Re: 400hp 351w startup tune

Posted: 2023 Jan 15, 01:57
by efloth
Just started digging into the fuel system. Looks like the factory fuel and return lines are both 5/16 on this truck. My 91 has 3/8 supply and 5/16 return so I was surprised to see this. Should I leave as is or ditch it?

Re: 400hp 351w startup tune

Posted: 2023 Jan 15, 12:35
by decipha
its fine

Re: 400hp 351w startup tune

Posted: 2023 Feb 07, 01:08
by efloth
Does anyone have an opinion on using the stock torque converter with this level of power? Getting closer to installing the engine but will wait and buy a new converter if y'all think that is necessary.

Re: 400hp 351w startup tune

Posted: 2023 Feb 07, 07:22
by red5.0fogger
It could be fine but I'll mention a couple things. Depending on how choppy the cam is, the engine may be sleepy in the lower rpms. If the convertor is really tight at that point the take off will be sluggish until she's on the cam. The other thing that could happen but prob won't, You can overpower the coupling ability of the convertor or drive "through it" and power will be wasted. This scenario is more likely when making huge power.

Re: 400hp 351w startup tune

Posted: 2023 Feb 07, 15:19
by efloth
Thanks for the input. The cam is a TFS Stage 1 with listed powerband from 2k to 5500k. Should I expect it to be super lazy below 2K? I did install 1.73 rockers so would that help the bottom end a bit?

Re: 400hp 351w startup tune

Posted: 2023 Feb 07, 17:26
by Sevensecondsuv
What's the duration, lift, and LSA? The advertised RPM ranges on cams are pretty much pointless. A given cam is going to be very different in a 302 vs a 351 vs a 408. I don't have much experience with automatics, but I've always heard you should buy your converter based on your cam.