I have an 86 IROCZ with tpi 305 and an auto trans, and it has acceleration issues. Once you are going and the rpms are up, it does decent, but idle to about 2500 rpm, has a bad lag to it. It has new plugs, wires, air filters, gutted air box, new fuel pressure regulator, new catylitic convertor and fuel filter, and it just passed smog, no problem, but I cant figure out where that drag is coming from. The engine has around 150k miles, and runs and sounds good, just seems to be holding back..... Also I changed the trans fluid and filter. Any ideas would be great, cuz im kinda stumped on this one, thanks again, guys

 

im going to guess its the 305, throw a 350 in and you'll be good .

i have an 86 iroc and have the same problem with 48,ooo miles

 

Yeah, thatd be sweet, a new engine is a lil outta my grasp, plus thats a lil more work than I want right now. If you wanna buy me one, then Id be down, lmao. Its a good engine, seems tight. No leaks, and doesnt burn oil, just plows thru gas. But other than that **** is sweet. I think the power is there from the engine, maybe fuel, or maybe trans. I dont know right now. To me everything seems about right, but its just kinda a dog when you're taking off.

 

i take it you just got your camaro ??? i was the same way, thought my car was the fastest thing around and could take on anything. then i got beat by a ford focus

although i think i could take him now because i know how to drive it. but still

 

Even with a 305 it should yank out of the hole strong , yea a 350 has a little more power ( stock ) but you should be able to light up the tires , idle to 2500 should be your strongest power band so somethings up .
When did your problems start ? has it been this way for a while ? You have listed all these new parts did anything hurt or help the problem ?

 

Had it about 6 months

 

I got this car about 6 months ago from a coworker for 800 bucks, he bought a year before and just never fixed it up. Just parked it. Just some front end damage and needed a tuneup. Everything Ive done so far to it Ive already listed, it has always had that lag since I got it. Everything Ive done so far has helped a little. I think the only thing I forgot is i was told that lag could be caused by the iac, so I followed the instructions on this site to reset it, and it did make a noticable difference. But it still has that drag till I get over 2500 rpms or so. Any ideas what else to check? Thanks again you guys know your stuff!

 

do you know what rear gears it has? if its geared high it will be a dog out of the hole.my transam had 2:73s in when i got it, didnt have any power until after 2500 or so. put 4:10s in helped like everything, although i do wish i had installed 3:73s.4:10s are a little too low, but they did improve gas milage.the car went in and out of overdrive a lot with the 2:73s, quite a few hills on the way to work.with the lower gears it stays in od. all the time.go in the homepage on this site ,go into tech articles ,scroll down to gears ,great article.maybe this will help,hope so, good luck ,later jimmy

 

After I did a cam swap in my car it was dead off the line. Even after I set the timing. I found out the balancer had slipped and the timing was way off. I got a proform balancer cover and reset the timing. Its all good now

 

Im pretty sure shes all stock in the engine. I have 273's but shouldnt it still have some get up? I have a 05 focus with a 5spd and 151 horses, and that 4 banger will take the camaro. I know that its 20 years newer, but that camaro has a lot more torque! Shouldnt it smoke that four banger? I guess its geared pretty high I think I run just about 2k rpms at 55 or 60. does that seem right? It does good cruising on the highway, but I have my gas saver, I want my tire smoker now. So is that how it should be running with those gears, or could I have a problem somewhere else?

 

funny story that 4cyl i lost to was a focus 5 speed. you should be able to beat it once you learn to drive the camaro. not saying you cant drive, just every time you get a new car you have to learn how it needs to be driven. when i raced it it was from 30-80 but i got him one race. i would suggest getting a posi rear end and some nice slicks. that way you can hook up better

 

check your throttlbody, if its an aftermarket from a former owner, they may have bought one too large for that motor... i am about to build at 383 stroker with my 350 tpi and i was told not to go with the 58 mm twin throttle body, if i go with the 52mm i will have better throttle response. im not sure what size came in the 305 stock but if im going to be pushing that much power and will run a 52mm if the former owner bought a 52mm thinking more air = more power without consequenses, that could be your problem. if its not that i really dont know.

 

Maybe it has the wrong throttle body, how do I know if its stock? Also I was telling a friend about the problem, and he said maybe it has an aftermarket chip, could be throwing the timing, or fuel off. Or if it is a chip, maybe the octane isnt high enough for it to work right, how do I know if theres an aftermarket one installed?

 

I think timing / fuel is the best place to look first , have you test the fuel injectors solenoids with an ohm meter ?

 

I checked the timing it was almost dead on, but how do i check the injectors, do I have to remove them?

 

You don't have to remove them , on the top of the injector there is a spring clip you have to push it in to unplug the two wires that make it pulse , there are two little metal terminals inside you need to ohm between to check the resistance of the solenoid .
If you search the tpi foroum and use the key word ohms you'll get a pile of hits .

 

I didnt get a chance to check that yet on the injectors, but on strictly highway keeping it right under 65, and runnin a lil higher than 2k rpms, Im only pulling about 18 to 19 mpg, and that is babying it. I didnt open it up once the last 2 tanks and its all on level ground. I saw somewhere it should get 16 city, and like 24 or 25 highway, and in town I usually see like 12 or 13. I did the basic tuneup as I stated before, but if I had a bad injector shouldnt it have failed the smog check? Maybe it just has bad injectors, but I have no trouble codes..... I gotta figure this out! lol

 

Ok, I finally checked the injectors. They are all at 17 ohms, with everything else done, what else should I check?

 

what plugs did you go with? what's your fuel pressure set @? check your timing yet? what kind of cat did you put on? consider bad torque converter? there's a lot that could be screwing with you. you're gonna have to go over all the basics and once that's done and you still can't find it... time for some serious wrenchin!!