I have about 500 bucks to spend on an ECU Will that take care of my car cutting out at 112 mph and help my boost what's the best thing to buy for that what's the best chips I guess any help would be much appreciated
I think I can separate that into a couple if sentences/questions...
You can either buy a reprogrammed PCM from a company like ZZPerformance for ~$200, or learn to do it on your own using HPTuners for $300-500 (but that's a pretty big learning curve and time investment, not really worth it when you are just getting started).
Anyone who has HP Tuning software can adjust the speed limiter with three clicks of the mouse. As for aftermarket ECU's I do not know of any self contained units that can shift the 4T65eHD transmission. If you go on the HP forum you will most likely find someone in your area that has the software and can help you. It costs $50 for a license to access your PCM and I would think that an HP owner would charge you modestly for a few minutes of work. Its far better than buying an ECU where you will need to start the programming process from scratch.
The difference between changing the limiter-only, and getting a vendor-programmed tune that includes that plus the fueling and other tweaks that make sure someone wanting to banzai down a highway at 100+ in an inefficient stock engine, is night and day.
Things like PE A/F vs. ECT, time, RPM and so on are going to start getting to places that will chip pistons, and let you start a new post here asking where/how you should approach an avoidable engine swap. If I hadn't seen this a zillion times since the dawn of this club, this wouldn't instantly come to mind.
This post shows the need for information regarding all the factors involved. Logic dictates advising a new person simply asking about removing a limiter to get it done in a way that won't cause a more serious issue soon after... and obviously they can be immediately shown that stock PCM tuning is the route for this platform, so $1,000+ aftermarket stand-alone options are wholly unnecessary in this case.
I've used HP Tuners to program PCM's for quite a few years and there is a case to be made for optimum tunes that support modifications. However, the OP has a stock engine and IMO there is little you can do to get more horsepower with a custom tune. He could go the route of a smaller pulley for a bit of a power boost but smaller than a 3.4" will most likely require adding an intercooler.
A) you are right that tunes don't add much power for stock engines, but making adjustments to tables that preserve optimum A/F in new parts of the tables not typically seen, or when abused by a heavy right foot, is what the goal is. We did this before HPT even existed and DHP or piggy-back electronics were the only option 15+yrs ago, and results spoke for themselves.
B) smaller pulley is a new arena to get them into, but even a 3.4-3.5 isn't going to perform well without some basic bolt-ons and a tune that adjusts for the new conditions... You'll get the quick kick in the pants, but it falls on its face or fails to increase power overall if things aren't setup to take that extra air.
C) going below a 3.4 pulley is 1,000% fine without intercooling, with valvetrain changes. I had all of my M90 fun non-I/C with 2.7-3.0-3.3 pulleys on, depending on what fuel I was running (93-104 unleaded, and L67 or L36 block). Going with an IC is preferred, but efforts can be made in multiple directions with success.
I appreciate people posting to help, but blanket statements that ignore proven alternatives create a cookie-cutter or stovepipe of information. There's also consideration of what to tell a new person based on the way they present a question, which indicates intent and level of understanding. (That's about the nicest way I can say it, versus the regular way we'd talk about this in a shop with more colorful language and laughs.)
First I want to thank all of you for the great support... So does anyone have a link to a aftermarket pulley that won't damage my supercharger while still giving me the extra boost that's safe to use with my stock engine after that I'm going to save for a intercooler and possibly an e85 conversion? This advice is priceless and I am so happy for finding this board. So I can't buy a aftermarket computer for the car that I can replace the old one with, I also plan to install a down pipe with the pulley. And some air box mod at the same time. Thanks for any help..
You certainly aren't limited to buying from them. Intense-Racing is still around, and some of those less specific parts can be had for more competitive prices at other stores online or in-person (air filters, spark plugs, etc.). You can get an idea of what you want to get for overall supporting parts before spinning the pulley too much harder and causing more issues than fun, which is the goal.
Or if anyone wants to tell me which mods to start with? I mean I have to start somewhere.. I'd just like to know where to start? Thoughts or 💡 ideas for my 3800.. the last car I had that was air assisted was a 1987 glhs shelby charger 2.2 intercooled.. they were quite different All I had to do is go to a hardware store and spend $3 to give myself 18 lb of boost and it was intercooler so it was good at 18 lb and yeah I just didn't have to do much to the exhaust cuz it was already done to it pretty much from the factory and this 3800 is a whole different type of power I'm just trying to figure out how to get more of it thanks again
Hey fellas I went under my car to look at the measurements for a downpipe and apparently the Riviera doesn't have a bent down pipe The down pipe is perfect from the factory That's weird that they did that it still has like some weird glass pack but we cut that out of the way yeah it didn't seem to even make that much of a difference because it was there was no restrictiveness before is my buddy that had a GtP was underneath the car with me and told me that he couldn't believe his eyes that there's not that you've been downpipe kind of makes me happy though less money... Have you guys ever heard of this or do you know about this ?
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