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All of the smog equipment was left in place except it's missing hoses things are disconnected it's missing the belt for the air pump and it's also missing the cat I'm having a high-flow cat put on it but how do I hook up all of the other emission controls since I need them to pass my smog test in Arizona now here's my question does anybody have a diagram for a 5.7 L engine in a 1986 IROC
I don’t think there was a 350 offered in 86 in the f body.
If you post up the letters on the computer chip I can identify it for you.
I’m guessing it might be for a 305 still. The 305 uses 19#hr injectors and a 350 uses 22#hr injectors. If you do t have a custom tune already you might be running rich.
You can use 88-89 computer chip in your ecm.
The guy I bought it from said they put a 350 TPI in it 5.7 l but all the smogging and everything is off and yes it is running rich you can smell the exhaust. The other part is all the smogging and everything is disconnected I need to reconnect because where I live in Arizona 1986 you still have to have an emissions test
As far as the ECM goes I think you might be correct because when I turn the power on my RPM gauge pegs out none of the other gauges read except for the fuel gauge miles per hour gauge is an 85 mile per hour gauge so it's off on speed and my oil pressure pegs out at 60 sometimes it drops down halfway but there's a lot of problems with this car it's just that it's my dream car and it's a labor of love at this point so I need as much information as I can get about the ECM and also where to find it and how to hook up all the smog stuff so that I can pass the smog and drive legally
This is a basic idea of how the air pump is plumbed. There is a crossover for the air pump line that connects both exhaust manifolds/header air pipes. If your headers don’t have air tubes I’m not sure you can pass a visual inspection if the do that.to identify the injectors to see if they are from a 350 they will have a number or number and letters on there body.
The computer is under the passengers side dash under the dash speaker. There is a bracket the ecm is held in that’s bolted to the dash frame.You remove the ecm from under the dash. Once dropped down you can remove the center access cover. You should see a blue chip that has 4 letters on a silver sticker. Unless someone has changed it to a aftermarket memcal.
You might need to disconnect the ecm plugs. To do this press down the connectors latch and pull the connector. I would disconnect the battery first.
Last edited by Tuned Performance; 01-31-2018 at 03:10 PM.
I don’t think there was a 350 offered in 86 in the f body.
If you post up the letters on the computer chip I can identify it for you.
I’m guessing it might be for a 305 still. The 305 uses 19#hr injectors and a 350 uses 22#hr injectors. If you do t have a custom tune already you might be running rich.
You can use 88-89 computer chip in your ecm.
just checked the numbers on the side of the fuel injectors and the part number on there is 523-5047 now I looked it up and I found one fuel injector on eBay for like 19 bucks and it says it's for a 305 but yet I'm running a 350 TPI in here so exactly sure but I'm going to check the computer and see what it says also so would I also be running rich if I'm running 305 injectorsto
The Hypertech has a number on it to identify its usage .
If you rock back the white and blue tabs next to the memcal it will pop out. If your careful you can release the memcals cover it has tabs on each end. The tabs break easily.
To reinsert the memcal it has a notch in the bottom center this notch matches the notch in the ecm header.
Last edited by Tuned Performance; 02-01-2018 at 11:55 AM.
Im wondering if you have a 305 or a 350.The block is behind the drivers side head would let you know. if you have leaking injectors. I’d think it would be running lean with 19#hr injectors. Any check engine lights present ?Or if the engine is rich after it’s warm but not too bad cold startup a o2 sensor. The o2 must get to 5-600f to become active this can be a problem in headers without a heated o2. http://www.chevyhardcore.com/news/re...sting-numbers/
Last edited by Tuned Performance; 02-01-2018 at 01:07 PM.
Reason: Additional information
[QUOTE=irocrocks1234;6198773]Ok. I will post a pic. Did you see the post where I sent a pic about the fuel injector?
pulled Hypertech chip out.. PN: 156332
SN: 626853...
Checked numbers on passenger side behind the alternator and I found some numbers on the Block and some numbers on the head I will try to post those so somebody can tell me if they mean anything
Thank you so much for that link the only thing is is there's three of the CHL codes on there one is from a 1991 305 lb 9 with TBI I'm kind of leaning toward that since I do have TBI but when I bought the car the guy said it was a 350 and so is there any other numbers that I can look at on the engine block to see what this actually is?also what does a small numbers mean underneath the big ones that I sent. And numbers on the head?
Lb9 is tpi, l03 is tbi .you could pull a valve cover to get the head numbers. The lb9 has 081 heads and centerbolt valve covers. The best way to identify what you have is with the block number on the block behind the drivers side head.
The small number underneath the suffix is the last numbers of the vin vehicle identification number the engine came from.
Last edited by Tuned Performance; 02-01-2018 at 05:20 PM.
Okay thank you you're helping me out so much you have no idea. The Hypertech chip that I sent you pictures of and also posted the number part number and serial number of the chip itself what is up with that could you make anything from it?.
#'s on head mean nothing
I don’t know what the numbers on the head mean. The Hypertech is for a 305 so really with those injectors on a 350 you would be running lean if everything is operating like it’s supposed to be. With a 305 you would be running great.
I don’t have image for 86 tpi air pump.
It will look a lot like this carb air system image.
I have also included 88 image which uses a different air pump mounting bracket but the pipes should look close.
You might be able to find the parts you need bye posting a ad in the wanted classifieds section here. I think the brackets and parts are the same for 85-87 tpi .
The guy I bought it from said they put a 350 TPI in it 5.7 l but all the smogging and everything is off and yes it is running rich you can smell the exhaust. The other part is all the smogging and everything is disconnected I need to reconnect because where I live in Arizona 1986 you still have to have an emissions test
You have to pass the sniffer. That can be done without that stuff actually hooked up and working if the tune is set up correctly. You will definitely need it running correctly and have a good cat on it for this to work.
Last edited by Beater79TA; 02-03-2018 at 09:12 PM.
The two prong electrical piece is the oil pressure switch. There should be a connector that plugs into it near bye. I’m not sure if that’s a block casting number is maybe a date code. But the 5.0l large journal gives away it’s a 305.
There is a connector for that peace and yeah we you and I discussed the 305 part of it and the suffix code which I believe is SGU or SGH or something like that I believe this is off of a 91 IROC or Camaro or Z28 or something like that because you sent me a link with the codes on it. So for the electrical connector for the oil pressure switch would that be why my oil pressure gauge shoots all the way up to 60 and stays there as soon as you turn the key on?
The oil pressure switch is a backup for the fuel pump if the relay fails. The sender for your gauge is on the same oil pressure t or above the oil filter .
Looks like the engine was made in 90 but used in a 91 z28. There wasn’t a iroc in 91. In my opinion the engine is better than the 86 it has a roller camshaft.
Last edited by Tuned Performance; 02-04-2018 at 01:21 PM.
I’m guessing the second week of February 1990 just guessing. I’m not sure where to find out this information. I think the block number is on the side of the block visiable from below. Anyways you know you have a 305 not 350 like the seller said
Block number on driver side or pass side? And what is the difference between what came in this and the roller cam this has Now? More power? Better milage?
The block number might be on the passengers side or the ending numbers on the side of the block. 86 lb9 has 190 hp 285 tq, 91 lb9 was rated at 205 hp 285 tq.
The cam will provide less friction and smoother idle.
Last edited by Tuned Performance; 02-04-2018 at 02:20 PM.
Reason: Typo
The block number might be on the passengers side or the ending numbers on the side of the block. 86 lb9 has 190 hp 285 tq, 91 lb9 was rated at 205 hp 285 tq.
The cam will provide less friction and smoother idle.
Driver side 627 stamp Passenger side block 627 A.I.R tube .. only one... arent thier to be two? What is it? Driver side front by radiator below head lights.
That is the egr solonoid vacuum line. You won’t notice is running poorly it’s ported vacuum but you should repair it using a 5/32 vacuum line. It tunes from underneath the throttlebody to the solonoid from the solonoid to the egr.
Your kinda beating a dead horse with the engine block numbers since you know it’s a 305.if your trying to find the rear end ratio the rpo codes are in the center console. Or if you service the reared you can see the pinion/ring gear numbers on the ring gear.
That is the egr solonoid vacuum line. You won’t notice is running poorly it’s ported vacuum but you should repair it using a 5/32 vacuum line. It tunes from underneath the throttlebody to the solonoid from the solonoid to the egr.
Your kinda beating a dead horse with the engine block numbers since you know it’s a 305.if your trying to find the rear end ratio the pro codes are in the center console. Or if you service the reared you can see the pinion/ring gear numbers on the ring gear.
lol....love the gif..... I am just trying to find out all the numbers I can so that I have them on file and just for reference or whatever and also trying to find out if this is truly a 90 91 like you were stating and just trying to find out as much as I can about this engine the numbers on the head that I sent you I'm not sure what those are I know you told me but they don't match up to my VIN number probably because it's not the right engine for this car found out through a Carfax that's his car was once stolen but it was recovered the very next day so I'm just know there's mileage differences on here by like a few hundred thousand on that Carfax and they just bounce up and down back and forth upside down and inside out that kind of crap so I'm just trying to find out as much as I can I've read in the forums wear a 9 bolt rear end is good gear ratios and I'm just real unfamiliar with these cars so I'm trying to find out as much as I can about them and as far as the EGR valve goes thank you so much
That is the egr solonoid vacuum line. You won’t notice is running poorly it’s ported vacuum but you should repair it using a 5/32 vacuum line. It tunes from underneath the throttlebody to the solonoid from the solonoid to the egr.
Your kinda beating a dead horse with the engine block numbers since you know it’s a 305.if your trying to find the rear end ratio the rpo codes are in the center console. Or if you service the reared you can see the pinion/ring gear numbers on the ring gear.
found some stock exhaust manifolds with the air tubes, just wondering two thing... 1. Will these work? 2 they have a 2bolt flange and I have 3bolt,so if I have the shop cut the 3 off and weld a 2 would that work?
The passengers side manifold is missing a spacer on the outlet.
I’m not sure if a shop can adapt them or if the need to build a new y pipe.
Sounds like you can pass without air system I’d get a cat figure out your running rich condition and take it in to be sniffed.
Last edited by Tuned Performance; 02-06-2018 at 06:13 PM.
I don’t know the tpi / tbi part number. I doubt you can find it at a auto parts store.
Carb version was gm 5234845 with a egr valve but you don’t need that.
The passengers side manifold is missing a spacer on the outlet.
I’m not sure if a shop can adapt them or if the need to build a new y pipe.
Sounds like you can pass without air system I’d get a cat figure out your running rich condition and take it in to be sniffed.
01-31-2018, 02:26 PM
