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2005 Impala SS 129,000 miles in June 2021. 86 Olds 442 with a '68 Olds 350
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Discussion Starter · #1 ·
I have something I'd like to get an opinion on from the gear heads out there that are using the aeroforce gauge. For little background on this deal I've had this 05 Impala SS since 2009. In 09 I put a front power log on it, did the FWI using the factory air filter box, 180 stat and the Ubend delete. Left it that way until last fall. I got the ZZP 3" DP and the 3.5" pulley. I figured the 3.4" would be iffy and not worth the potential KR nightmare. It has the 180 stat and Autolite 605s . The DP really woke it up but the 3.5 pulley did even more. We have 93 octane here in Mich. I've driven it about 3000 miles on it mostly in cool weather. I just got the aeroforce gauge a few days ago to check KR. I'm seeing 4 degrees max between 5000-5800 when it shifts. Out of curiosity , I tried 16 ozs of Torco in 10 gallons(raising octane to 97) but it didnt seen to affect the KR. No part throttle KR and I usually dont see it until Im past 4500 rpms. Out of curiosity, I pulled the plugs just to see how they were burning. No pitting, no white color,just an even tan electrode, wire and porcelin. I need to get an mail order tune from intense before the warm weather gets here and I suppose it will knock out that KR? The strange part is the 0-60 on the Aeroforce. With these basic bolt on and a stock tune, it claims I'm doing 5.7s 0-60? I did 3 runs on a day where the temps were in the low to mid 60s. I rolled out to 15 mph then punched it, it hooks. The car is quick no doubt. Low end torque is very strong but 5.7 seconds seems a little generous. Are these gauges accurate? Are there any other 3.5" pulley guys out there with a stock tune or mail order tune running 0-60 in the high 5s?
 

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1998 GTP coupe. All stock and rust free. That will change soon.
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have you done any MAF tuning at all? Your issue sounds typical where you are flowing more air but the fuel curve hasn't adjusted, so you're locking lean and that can cause KR. Even a basic tune can quench some of that KR
 

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2005 Impala SS 129,000 miles in June 2021. 86 Olds 442 with a '68 Olds 350
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30 Posts
Discussion Starter · #3 ·
No MAF tuning. I don't have any tuning equipment. Only think is the Aerotech to monitor. Your explaination sounds like that would remedy the situation without much difficulty .....if someone had the tuning equipment. Would a basic Intense PCM "canned tune" most likely quench that KR? I just went out and tried that aeroforce gauge again for a 0-60. It's 57 degrees out and it "claims" it did a 5.51?( no wheel spin at 15 mph) Does a 3.5" pulley with the right upgrades actually support this kind of 0-60 or is this aeroforce a little too generous? Thank you for the quick response. I almost went with a 3.4" pulley but I figured no way with a stock PCM tune and even with a custom tune, I'd most likely need 1.9 rockers then with the extra low end torque, there's even more of a traction problem. The 3.5" pulley and your MAF tuning sounds like the simplest and best plan.
 

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A basic tune from Intense or ZZP should richen it up enough to help some (their basic tunes are meant for these typical bolt-ons), just make sure your Long Term Fuel Trims aren't locking in at more than +/- ~5% when you get into the pedal, or it'll be skewing the fueling enough to require additional tuning. The 3.4-3.5" pulley has been the staple for most starting modders since these engines got started, as long as intake/exhaust/tune components are improved with them, and proper maintenance like 605/104 plugs, 180 tstat, and everything else is in proper working order (harder to ensure as these cars age).

I wouldn't base much on the 0-60, as that's much more of a magazine-humper metric that's not too applicable or reliably measurable for man-on-the-street purposes (hence it's only referenced 99% of the time to OEM cars being marketed). It's also why you see people who want to quantify gains in their vehicle's acceleration performance go to the drag strip for a comparable metric against themselves and others.
 

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2005 Impala SS 129,000 miles in June 2021. 86 Olds 442 with a '68 Olds 350
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Discussion Starter · #5 ·
Thank you for the info. I've just recently got into the whole concept of how a 3.8 is tuned. I comprehend most of what is said on these forums however I've never actually got into tuning myself. Most of my life (58 now) I've been old school with a 86 Old 442 with a 68 Olds 350/turbo 350 3000 stall/ 3.73s. HEIs/ 650 Holley DP is a little different than altering the AF ratios/ maps/ spark advance, etc... but I keep learning as I go along reading up on all of these different posts. Once this PCM issue is ironed out, I'll most likely stay with the 3.5" pulley and not venture into 3.4" territory. Original trans with 127,000 miles. I'm probably already pushing it hard enough. The gain from a 3.4 and potential KR issuses doesnt seem worth the trouble with a novice like me that isnt into tuning myself.

I agree that 0-60s are a little over hyped and talked about too much. Great marketing numbers along with HP. I was just a little skeptical of the accuracy of these Aeroforce gauges. That's new to me also and I didnt think a 3.8 with these basic mods would be capable of sub 6 second 0-60s but then again, that's the first time I ever timed it in the 12 years I've had the car. Wow, 11.40s at 122. I thought 12.50s with that Olds I have was cruising. Buicks make the best sleepers and in total luxury. My dad was a hard core Buick man. I can still remember what the old 401 nailhead looked like in his 64 Wildcat convertible. Carburetors, points ignitions, no air bags, ABS, traction control, bias plies. Seems like a hundred years ago.
 

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I wouldn't get too spun around the axle on the miniscule difference of 0.5-1psi boost difference in the 0.1" pulley change. The drop from a stock 3.8" is already significant enough to ensure you have all the components ready to deal with some more demand.

Comprehending how to increase airflow and fueling is common regardless of turning a screw on a carb, twisting a distributor cap, or changing more accurate values in tables that now get more accurate data from sensors. Most high-end old school engine builders tend to appreciate the improved ability to optimize things, and love that the detailed sensors they only had on their engine dyno's are now on everything from a Vette to a minivan. Heck, even the tech in these 3800's is now a generation old, and I'll be looking to try new things when I'm ready to buy something direct-injected (besides my truck) or even electric down the road. There's always room to appreciate older styles/tech, while appreciating how updates can improve performance when applied right.

Thanks, and I'm hoping to cut about another second off it soon, once I get ready to hit tracks (tune, race gas, cage, etc.). The sleeper thing is kinda fun, although I prefer the Pontiac looks more, but this was originally assembled for a buddy who moved on to other vehicles and offered it up. I'll rock it for a while, since it's so clean, but want to try more platforms that push the envelope further.
 

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2005 Impala SS 129,000 miles in June 2021. 86 Olds 442 with a '68 Olds 350
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Discussion Starter · #7 ·
I hear that about old vs new. When I started as a dealer mechanic in 85, it was the old C3 system on GMs. I left just as OBDII came out but just picked it up as I went along on my own vehicles. Being familiar with diagnosis and repair , I understand the concept of tuning,mostly, but have never dove into it. Anyone that thinks carburetors/ sticking chokes/ saturated floats/ choke pull offs that dont work/ low voltage points ignitions that crap out when wet or old plugs gapped at .030 that fouled out with leaded gas, lousy gas mileage, more frequent tune ups, etc was the way things should have stayed doesnt appreciate the ability of modern engine controls that manage the fuel and ignition systems. The whole powertrain for that matter. It just took me a little while to crawl out of the 70s.

Another second off? That's getting into some hard core speed. Sounds like you have a drag strip to go to. Up here in metro Detroit, our one and only Milan dragway is closed for the season. Mid michigan (US 131) is 145 miles) Norwalk OH is 125 and the nearest, Lapeer, is 75 miles but kind of a dump. However, the old hot rod Oldsmobile I have seems to be taking a back seat to the more highway friendly, air conditioned, overdrive, quieter , more sleeper like, fuel injected Impala. Seems some of us do a little more bench racing than actually racing as we get older. Maybe the luster of the dragstrip wears off on some people after 35+ years! Good luck pushing that envelope and hitting the 10s. Thanks for all the info.
 

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I used to go to Milan during the ~5yrs I lived in SE Michigan during the peak of 3800 times (early 2000's). Avoided Lapeer, but tried Ubly once or twice, and Norwalk was usually what the Motor City GP club would rent for a day when that group was still active 15+yrs ago. I think US131 or elsewhere is where the western MI & ZZP guys go, if I'm not mistaken. Most of the crowd has moved on, so unless you're a die-hard stubborn person like me, with parts and tuners to keep it going solo, I'd refer you to just getting what you need from the remaining vendors while they last.

I actually finally got around to being able to truly afford to put the parts into this that I wanted after age ~35 or so, and happened to build this car with everything available at the time (trans parts, etc.), so it's the only reason I'm still tinkering with 3800's. My dad and uncle still competitively race multiple drag/oval platforms as they've reached their older years as grandpa's, so maybe it's just considered normal to always continue it.
 
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