All of my TBI systems act like that. I've never seen it as a problem. Are you having any issues?
All of my TBI systems act like that. I've never seen it as a problem. Are you having any issues?
1973 K-5 Blazer, TBI 350, TH400, 1 ton axles & 38" SSRs'
1975 280Z, TBI 350, 700R4
1953 M-38A1, TBI Buick 231
1951 Ford Panel, 5.3 with 4L80E
yes. when i climb a hill the exhaust manifolds start to glow within 30 seconds. we cup the tbi shut restricting air flow in and the glow goes away so it's been confirmed that I have
a fuel delivery issue. no exhaust blockage, new catalytic. timing is good, engine has been rebuilt in fact with timing chain and new exhaust manifolds. no vacuum leaks and i put in a new
fuel pump, a new pump relay and the fuel pressure regulator has been rebuilt also. I am seriously amazed why this is happening but it cranks over right away good power. Even the computer
has been replaced.
What's your pressure dropping to when the manifolds start to glow? If the pressure is dropping when it glows, then maybe you have a kinked fuel line or some other type of restriction that allows decent pressure except at higher flow rates? I had an '89 454 Crew Cab 4x4 for a while and it always got pretty hot on the hills too, even though there was nothing wrong with my fuel system. I'm not sure how well GM tuned the 454 TBI for heavy loads. I didn't keep it long enough to really dig into it, though.
1973 K-5 Blazer, TBI 350, TH400, 1 ton axles & 38" SSRs'
1975 280Z, TBI 350, 700R4
1953 M-38A1, TBI Buick 231
1951 Ford Panel, 5.3 with 4L80E
my thermostat was upside down ran hot when I pulled up one hills in flagstaff till the fan started pumping I could bet on it staying in open closed loop check your vacuum at idle and timing I swear my vac was like 30-40 in so I put a lot in it oh it was hot could cook dinner at idle
Last edited by De-stroker; 04-19-2017 at 11:54 PM.
Maybe try setting the Power Enrichment (PE) Delay or Wide Open Throttle Delay to ZERO seconds in the PROM Chip. See attached screen shot showing BCC BAMM with a WOT delay of 70 seconds! PE is similar to having the secondary's of a 4 barrel carburetor opening up.
dave w
IMO you have confirmed that a richer mixture does not cause the manifolds to turn red, but you have not confirmed a fuel delivery problem. Do you have access to datalogs or scantool readings? Have you confirmed the timing is actually set where it shuld be set?
I believe we hashed this to death in the other thread : http://www.gearhead-efi.com/Fuel-Inj...-P30-Motorhome
Last I left it there was no hard data that the injectors actually flowed what Rock Auto said they did , and again , 12 psi is no where near enough to fuel a BBC under load , Period.
TOM
1994 3500 Dually , 502 (509) , 264HR , Edelbrock MPFI , PFI '7427
1992 S-10 434 SBC/Tremec - '7427
1986 Monte Carlo SS
1984 S-10 , SAS, 496/700R4/205 , D44/14BFF -'7427
1980 Z-28 496/700R4
1979 Corvette 496/700R4
1977 Olds 98 Regency 403/700R4
I was having a hell of a time finding real 454 injectors almost everywhere I looked has 350 and 454 as the same part number
I have to guess the last owner of my truck was trying to get better mileage since there was one of the wrong injectors in it when pulled the radiator i found what I think is the right big block injector but it's so rusted I can't use it anyway smh!
Last edited by De-stroker; 04-21-2017 at 11:19 PM.
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