PaulJ2 wrote: Amazing what a reprogramed spark advance curve will do. Can you still run regular 87 octane fuel?
I do not think our 1992 454 TBI has been chipped but it does have more power and better MPG running 93 vs 87.
It is my suggestion based on our owership experience that if one has and older 454 is to run three back to back tanks of 93 octane. If pulling the same hill with the same load in the same kind of weather does not go faster when running on pure 93 then go back to a lower grede.
Brian does seem to know the 454 very well and at one point owned a 454 SS truck.
PaulJ2 wrote: Amazing what a reprogramed spark advance curve will do. Can you still run regular 87 octane fuel?
Yes, I am running regular gas no problem. As I recall the compression on that generation was pretty low. I did stick a tank of 89 in it last fall out of curriosity and it did, arguably, get better gas milage, but that was only one tank and 150 miles so not really long enough to tell for sure, but then the gas prices went through the roof so I can not afford anything but regular.
This summer I am going to pop the front off and get rid of the stock timming gear which has a 4 degree retard and put in a good chain and gears with cam timming set at "0". I am still waffling about going all out and putting a better cam in it. Lot of work and $$$.
1991 Chevy Western Hauler 454 engine - RV cam, Headers, Dual Flowmasters, K&N 100 Gall Aux Gas tank
2004 29' Crossroads Cruiser 5th wheel
4 Interstate GC Batteries + WM Caps
2 daughters, 1 cat, 1 sofa lounging Pug, 4 peacocks, too many horses & chickens!
It is nice to see someone towing with a vintage TV.
There was a reply on this forum one time where someone asked how people manage to to 30 ft trailers with less than 300 hp.
My reply was something like, we hitch up and put the truck in drive.
thanks!
Jeremiah
Yep, that is pretty much what we do, hitch up and aim 'er down the road! I find that Gertie can tow just as fast as I care to go 99% of the time. She likes to run between 65 and 70 which is all the faster than I care to go so were fine. The other 1% is going up the side of a mountain and I just go slow and enjoy the scenery more.
On My old 93 GMC Suburban with 454, Towing Chip from Brian and had a cold air intake and this made a big difference. But when I added headers with good flowing cat and muffler it really finished off the package. I also had the TBI bored and replaced the fuel pump with better flowing unit. It ran so much cooler then it did before. Those stock cast iron manifolds rob a lot of power and causes heat to backup in the engine compartment.
1997 Ford F250 Extended Cab, 7.3 Diesel, 8 foot bed.
Reese 16K Hitch
(Moved into Shed) Hensley Arrow
Jordan Brake Controller, Hensley TruControl Gold Shelved.
Open Range 5th Wheel, Roamer RF392 BHS
I do not think our 1992 454 TBI has been chipped but it does have more power and better MPG running 93 vs 87.
It is my suggestion based on our owership experience that if one has and older 454 is to run three back to back tanks of 93 octane. If pulling the same hill with the same load in the same kind of weather does not go faster when running on pure 93 then go back to a lower grede.
Brian does seem to know the 454 very well and at one point owned a 454 SS truck.
That's likely because on 87 octane, you may get some pinging/detonation (especially in high ambient temps) which causes the timing to be retarded to prevent the pinging which = lower power. The ECM can "hear" the pinging via the knock sensor before you can. Running higher octane prevents pinging, no timing retard, no loss of power. This will be especially true if your truck is a high miler.
2010 Cougar 322QBS 5er
2007 Dodge 3500 SRW Megacab, 4x4, 5.9L Cummins, 3.73, 48RE auto HYPERTECH MAX ENERGY or DIABLO PREDATOR tuning MBRP 4" Turbo back Scangauge2 for Boost, Coolant temp, Rail press & Trans Temp
Torklift Stable Loads
Brian recommended 91 or 93 octane when towing with the towing chip. When I just had the Cold Air and chip running mine would ping on 87 octane towing. But after the header and good flowing cat and muffler, the reduced head / engine temperatures allowed me to run 87 just about all the time. I was running a 190 degree thermostat also.
I replaced the opiginal engine in my '90 Suburban with a reman unit from Jasper last year. The new engine has an upgraded cam and valves over original. Also added an Edelbrock aluminum intake and headers and dual exhaust and added a Gear Vendors overdrive unit. I too have Brian's chip installed. Made a trip by his shop and had him do a custom tune to take full advantage of the improvements. The truck runs better with more power than when new.
'90 GMC R2500 7.4L w/ Gear Vendor OD
'90 Avion 34V
Cummins Onan P4300ie
Pro Pride 3P
Prodigy
I do not think our 1992 454 TBI has been chipped but it does have more power and better MPG running 93 vs 87.
It is my suggestion based on our owership experience that if one has and older 454 is to run three back to back tanks of 93 octane. If pulling the same hill with the same load in the same kind of weather does not go faster when running on pure 93 then go back to a lower grede.
Brian does seem to know the 454 very well and at one point owned a 454 SS truck.
That's likely because on 87 octane, you may get some pinging/detonation (especially in high ambient temps) which causes the timing to be retarded to prevent the pinging which = lower power. The ECM can "hear" the pinging via the knock sensor before you can. Running higher octane prevents pinging, no timing retard, no loss of power. This will be especially true if your truck is a high miler.
I expect your thoughts are on target. We are at 109K miles and 20 years old. It is in a P30.
quit screwing around with chips and exhaust and cold air intakes...Call Edelbrock and get their multi point injection kit for your tbi 454...an easy bolt on and it makes the 454 run as it should have from the factory. Best $$ I ever spent on my bought new 91 454 CC dually that was a PIG from day 1 until it got the injection swap.
no I do not work for Edelbrock, nor sell their products...the above was my personal experience while having the above truck that would barely pull my enclosed race trailer above the minimum posted speed limits here in MO
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