Cascade Crew

Spikeophant · Posted: Fri Mar 12, 2010 1:18 pm Post subject: Carbbed 350 -> TPI

I have an 86 Iroc with a 350 swapped in, it has a bunch of the top end stuff off a 305 on it, carb, intake, etc. All the sensors, etc are hooked up and all work, sorta, they don't particularly like my setup. I want to convert to fuel injection, was thinking a stock 350 TPI system. If I have a crate 350 block, am I going to have to make a spot for a knock sensor, or should my engine be fine. I really don't want to swap blocks, I have maybe 30k on my engine/trans. It falls on it's face at full throttle with the carb on it though, well, anything past half throttle really. I'm going to fully tune this thing up in a couple weeks, haven't really looked at it too much. I think the cat might be starting to clog, as when I get after it as much as I can, it stinks like a bad cat. I'm going to do plugs, wires, distributor cap, rotor, etc when I tune it up, and see what the plugs say. It's giving me a VSS code and a code from one of my O2 sensors saying it;s running rich. Any advice on the tpi swap would be greatly appreciated, and any advice on my power issues while it's still carbbed would be greatly appreciated. I'm not doign the swap till nex twinter while the car is parked anyways.

Dewey316 · Posted: Fri Mar 12, 2010 2:16 pm Post subject:

I'm not such a huge TPI fan.

It sounds like you need to do the tune up, and probably tune the carb. If you are running really rich a lot, you can burn out the CAT pretty quick.

Alphius · Posted: Fri Mar 12, 2010 2:19 pm Post subject: Re: Carbbed 350 -> TPI

Spikeophant · Posted: Fri Mar 12, 2010 2:26 pm Post subject:

I've checked a lot of that stuff out, live in an Apt, so I can't work on it too much at home, my dad has a hot rod shop about 30 miles away I'm going to tune it up in, get it in the air and make sure everything is actually hooked up. The computer tuning of a tpi setups is a bit intimidating, haven't done that before, this is the newest car I've ever owned. I'll investigate about doing some ecu tuning myself, or a shop I can have tune it locally if I do the swap. Other than a stock tpi system, what fi setup would you suggest I get? Stock tpi will probably be cheapest to get all the pieces of from a junk yard, but maybe I can find a good deal on another fi system used somewhere? Any insight is much appreciated guys, just now starting my plan for this cars future.

izcain · Posted: Fri Mar 12, 2010 2:39 pm Post subject:

You should be able to tune that carb after a tune up and make the thing jump right up instead of fall on it's face! Seems to me that would be much cheaper then the EFI swap.

91RSVert · Posted: Fri Mar 12, 2010 2:46 pm Post subject:

The two main fi systems is TBI or TPI.

The TBI would be cheaper, and is easier to fix. But TPI can give you better mpg when tuned right.

either one you do, your gonna honestly need to tune it to what you have. So start schooling up on that. Ive been at it for 2 years on mine and still have no clue WTF I am truly doing.

To me it sounds like you need to really go over what you have now and make it run as good as it can. You may learn to like what you have.

Alphius · Posted: Fri Mar 12, 2010 2:49 pm Post subject:

You seemed pretty set on a fuel injection swap. I personally love FI.

If you can learn to love the carb and tune it up so it's not so slow that might be the best choice as others have said already.

Spikeophant · Posted: Fri Mar 12, 2010 4:10 pm Post subject:

Yeah, I'm pretty set on a fuel injection swap, I know how to work on carb'd cars well, I have built several engines, and do all my own work, from mechanical to paint. So I'm not really intimidated by either learning something new, nor having it be a really complicated swap. I really want to learn about fi cars, how it works, etc, so I thought this would be a fun project, plus I can improve drivability, reliability, and performance. On an unrelated note, my nose cone is pushed down a bit on one side, I notice this on tons of 3rd gens, probably a carelessly placed knee by a mechanic. Can I just pull the nose cone off, heat it from underneat, push it back up, let it cool, and it will return to the proper shape. The left side of my hood shakes at speed from air getting up underneath of it from the slight indent in the nose cone. If this doesn't make sense, let me know, I'll take a pic of it and upload it

aaron_sK · Posted: Fri Mar 12, 2010 4:36 pm Post subject:

If you are dead-set on fuel injection, and have some bucks to spend, consider a TPI harness with a Holley Stealth Ram.

The biggest complaint against TPI is the "wall" it hits at around 4500rpm. Click on my Garage link over here under ol' Harry <-- and take a look at my dyno curve. Note the point it falls off. That will be your shift point with TPI.

That said, if you want to ease yourself in slowly (spend less cash now, but more later on, and not have to jump headfirst into chip tuning) get the TPI setup going, then do an HSR swap down the road.

izcain · Posted: Fri Mar 12, 2010 6:32 pm Post subject:

Spikeophant · Posted: Sat Mar 13, 2010 8:40 am Post subject:

I live in an Apt and they get pissed when my hood's open. Most of my tools are at my dad's, and the shops full right now, and it's snowy outside where he lives, so I simply haven't worked on it. Was trying to get some ideas before I start, I'm going to do a complete tune up and retune the carb pretty soon. Got a Monte Carlo that needs clear shot and rolled outside to cure, then my Camaro can go in and get tuned up. I have a lot of projects...

Spikeophant · Posted: Sat Mar 13, 2010 8:50 am Post subject:

That and I've only had the car for around a month

Spikeophant · Posted: Tue Mar 16, 2010 12:36 pm Post subject:

I have my car running a lot better now. I dug around and found a lot of broken vacuum lines, missing caps, etc. I'm going to reset my computer over night tonight, and see if it continues to throw codes tomorrow. I'm doing tune up Sunday, plugs, wires, cap and rotor, I did oil to a full synthetic right after I got it. Still falls on it's face, but it has to be at upper rpm range now to do so, I'm thinking it's still got some vacuum leaks. I'll update once I've got her sorted.

Alphius · Posted: Tue Mar 16, 2010 2:14 pm Post subject:

Good to hear it's going a little better.

Spikeophant · Posted: Tue Mar 16, 2010 2:16 pm Post subject:

I retuned the carb too, but it still might have issues with the secondaries, I'm going to check them out this weekend, I'll get a vacuum gauge on her too and see what that says. It's a shame all my fun tools are in the shop 30 miles away, and I live in an apt and can't just tear into her at home....