Rebuilt 302 Tune need help!!

[CraKel]

Ok so after a few months of fiddling around the shop and only being home on weekends the engine is in, runs and got exhaust on the thing!!

Now, only problem is that is sounds like ass at idle and when I put in in gear she wants to die on me. Carb is a hollley 4160 600cfm, vac 2nd, no-egr, and 2 idle set screws.

Soo when I took it to the exhaust shop, while running it in the driveway it sounded fine, I knew it wasnt tuned properly and floats werent set right but i asked them to make me up a y-pipe and tune it because those kinda go hand in hand. Now that I got it back it sound like a major popping or ticking in the carb, almost like an exhaust leak but I have checked, I have tons of back pressure and no leaks from exhaust. If i rev to 2k or greater it goes away.. Shop guy said they couldnt tune it cause it didnt have an egr on it. So got an oem 4bbl egr spacer from a mid 70's 302 and installed it, with no change. After looking at the edelbrock intake I put on it however I noticed no hole for the egr in the carb port! Doh! Either way I dont think this is my problem.

I have since, put 30$ premium in it and looked at the plugs, they seem a little white and that means running lean correct? When I put it in gear it wants to die on me so i tried adjusting the idle screw, not the mixture and after 3 turns each way basically no change to the idle rpm.. Vacuum is all hooked up proper, only one I havent hooked up is vacuum advance for dizzy which I dont have.

Oh and lastly I think my oil is diluted, strong gas smell from valve cover breathers and oil looks a lil thin but doesnt ignite when lighter put to dipstick.. Gunna change oil out this wknd anyways..

Any thoughts guys? Its Novmber here in Ontario and I'd love to get this thing running right before it goes into storage before the snow hits.. Mind you its a rebuilt 302 bored .30 over, but I dont think it should sound like this even if it hasnt been road driven over 50km.

Here's some pics and vid of the sound...

 

[CraKel]

Heres the youtube link for the engine vid

http://www.youtube.com/watch?v=jysFzc0mPBs&feature=youtu.be

 

[CraKel]

Another thing ive been thinking about is timing, its not backfiring at all but after i give it gas it sounds fine.. Think it could nust be out slightly?

 

[Tominator]

Did you time it with a light? Some of your symptoms sound timing related.

If the idle screws make no difference and the timing is correct then you must have a vacuum leak.

Don't worry about the plug color at this point.

Nice work there BTW....

 

[CraKel]

I put it to factory settings and adjusted very slightly until it sounded right. I think its about 8-10 degrees btdc if im not mistaken. Ill look this week and time it with a light to make sure. Then check vaccuum out with a guage and report back.

Whats normal vacuum pressure supposed to be from this engine size without having leaks?

 

[Tominator]

One should be in every tool box....

http://www.international-auto.com/fiat-lancia-tips-on-reading-gauges/tips-on-reading-gauges-vacuum-gauges.cfm

 

[CraKel]

Ok good news a nd bad news. Seems like timing was off tgats what was causing the major popping in the carb. So thats fixed.. Vacuum at steady idle at 1200 rpm is bout 18-19 Hg. At idle in gear it drops to about 12-15 Hg. Sounds great in park, but vacuum and rpm fluctuate in gear and sounds like a miss. when driving it sounds like a leak somewhere but pretty sure its idle mixture related.. Started from factory idle mix settings and tweaked to max vacuum but still doesnt sound great. So close to getting this right. Might be a small vacuum leak but hard to say, whats highest vacuum reading at idle am I low at 12-15?

 

[CraKel]

Ok so tried every possible vacuum set up tonight with almost no change. Seemed better when i had full manifold vacuum port on carb hooked up to a hose barb coming out top of edelbrock performer rather than tieing it into the air cleaner. Still a major rpm and vacuum stutter when in drive though.. All other vacuum on carb are hooked up other than vac advance which my dizzy doesnt have. Is that really needed though? Its just a street driver no track etc.. I also tried adjusting the idle mix both ways and it either died or sounded like it was going to die (coughing carb). Any suggestions guys Im out of ideas?....

 

[shane96ranger]

What distributor do you have then?

EDIT: Nevermind, now the pics showed up.. Where are you running base timing at right now?

EDIT 2: I just listened to that video. It sound to me like it's missing.

 

[85_Ranger4x4]

You might start pulling plug wires while you have it running, if the idle doesn't change on one there is your dead hole.

If you are concerned with vacuum you might spray around the carb base, carb spacer and intake manifold with brake cleaner and listen for an increase in idle. Is the vacuum constant?

There is a crossover pipe that is part of the EGR system that crosses the back of the heads. It is commonly deleted in swaps, I know one other guy that didn't plug them and had a lot of exhaust noise. I don't know if it would effect drivability though but it could explain the noise. Did you plug them?

 

[CraKel]

Ya in the video it was missing slightly. After changing the timing should be about 10 degrees btdc right now and sounds great in park. Like i said its just awuful rinning in drive and the sound returns. I didnt know of this crossover pipe. But that def sounds like a possible leak area, any pictures of where this is. Just plug it with one of those allen head threaded plugs?

 

[superdave1984]

Get your timing set correctly before you start making any carb adjustments. Does this have a stock cam? If it's a bumpy cam your timing may need to be tweaked for it. Also a bumpy enough cam will make you need a looser torque converter. I am at work so I can't see the video. Here's how to correctlytune that Holley.

http://www.bob2000.com/carb.htm

Oh, and if you are getting backfire through the carb, go ahead and rebuild the Holley as you probably damaged the power valve.

 

[shane96ranger]

What heads are you using on it? There will be holes in the head that are supposed to go against the firewall. Then there is an EGR pipe that has one bolt holding it on each head. I have an E7TE head with the hole and the EGR pipe that I can get a pic of in a bit.

If that is your issue, I really hope the heads got lined up with them towards the firewall.

It is impossible to tune that thing properly with a misfire. Is that cleared up yet? Otherwise you are spinning your wheels.

EDIT: Please tell us if you are using a timing light. From your wording "should be at 10 btdc", I don't think you are. With a cam, I have found timing by vacuum isn't as easy. I only use a light now.

Sent from a Commodore 64 using a 300 baud modem

 

[85_Ranger4x4]

QUOTE=CraKel;1310433]Ya in the video it was missing slightly. After changing the timing should be about 10 degrees btdc right now and sounds great in park. Like i said its just awuful rinning in drive and the sound returns. I didnt know of this crossover pipe. But that def sounds like a possible leak area, any pictures of where this is. Just plug it with one of those allen head threaded plugs?[/QUOTE]

The pipe that crosses to both heads.

I chased the carbon out with a tap and just used a short bolt because they are straight threads, pretty good sized but I forget exactly. IIRC the factory plugs have a flat bladed screwdriver slot to get them out.

What heads are you using on it? There will be holes in the head that are supposed to go against the firewall. Then there is an EGR pipe that has one bolt holding it on each head. I have an E7TE head with the hole and the EGR pipe that I can get a pic of in a bit.

If that is your issue, I really hope the heads got lined up with them towards the firewall.

I would be hoping for the opposite... a lot easier to plug.

 

[CraKel]

Looking at the pic from 85 ranger4x4 i would say that is definitely my problem. Pretty sure i threw that egr pipe away now that i know what it looks like. Oh well ima just plug those holes on either side and try it again. Heads look same set up in the pic aswell. Should be the stock heads off a 79 tbird.

Timing was set to about 10 degrees using a light. Carb knock from video went away, but while in drive still get a major stutter and cough. Im at work but will try tonighy to plug those holes!

Thanks guys.