Help with 340 rebuild - Chicagoland area

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340runnee

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Naperville, IL
Hi, coming over from FBBO, already messed up my username, can't change it for a month so oh well. Supposed to be @340runner
I'm here because I know the A body guys are a lot more interested in the small blocks than the B bodies, and I have a 71 340 that's in need of a rebuild, I'm just unsure and kind of worried about doing it myself. It has already been freshly rebuilt, but the guy who last did it mixed and matched parts, it has 30 over stock replacement pistons, but for the low comp 340s, the l2385f. It also has a single plane intake, speedmaster heads and a 243/257 "big mutha thumpr cam". Right now, it's been driven for about half a year and is now starting to leak badly from the timing cover and is slinging oil everywhere, and when I step on the gas it puffs out a little bit of smoke, I'm thinking the valve seals.

Id like to use the above issues as basically an excuse to pull the engine and do a rebuild on it, swapping out the pistons for l2316f pistons, but I'm kind of nervous about doing the rebuild myself. This will be the first time I'm doing this kind of thing, and it'll be on a engine that currently does run, so the whole "can't be worse than before" thing doesn't apply. Does anyone know anyone in the Chicagoland area that'd either be willing to help with a rebuild, or i would be able to pay to rebuild it?

Thanks very much,
Paul
 
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Westech automotive run by Norm Brandes in silver lake, wisconsin is just over the border from you. Full service machine shop and automotive repair that has been featured in Hot Rod magazine numerous times in the past specializing in performance car issues. I believe they have a dyno for tuning as well.
 
ch1ll said:
Westech automotive run by Norm Brandes in silver lake, wisconsin is just over the border from you. Full service machine shop and automotive repair that has been featured in Hot Rod magazine numerous times in the past specializing in performance car issues. I believe they have a dyno for tuning as well.
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Its a option, but also I'm trying to both learn how to do this, I've done just about everything r&r wise, including trans drops, diff replacements and engine pulls. Now I'd like to actually learn internals, so rebuilding diffs, engines and transmissions. Other reason why I'd like to at least do some of it is I'm broke, I work part time and am on high school. I'm typing this out in my AP government class right now actually

Not opposed to paying people, but holy hell most shops I've talked to want at least 5 grand for just a rering.
 
There are several people in your area that belong to the Chicagoland Mopar Connection that would lend a hand. We had a web site, check us out! We used to have a show at Koller Dodge in Naperville but it has been gone a long time.
 
HemiSSDart said:
There are several people in your area that belong to the Chicagoland Mopar Connection that would lend a hand. We had a web site, check us out!
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I'm actually in the Fox River CAM chapter, I made it out in January and feburary to the meeting, i just haven't been able to make it to the last two because I've had work the last two tuesdays
 
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HemiSSDart said:
There are several people in your area that belong to the Chicagoland Mopar Connection that would lend a hand. We had a web site, check us out! We used to have a show at Koller Dodge in Naperville but it has been gone a long time.
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I was also there for the winter swap meet in Lockport
 
RustyRatRod said:
The link posted above is from @krazykuda Karl. He is in the Chicago area. He might be willing to help. I know he would at least with maybe a phone call. He's had some health issues lately, so I don't know how much bearing that would have, but Karl is a good guy. I tagged him so maybe he will chime in.
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Yeah, I have actually read his series on it, and I've done a lot of research about rebuilding engines, I just want someone there who's a bit more experienced. If I mess something up it's gonna be expensive, so I dont want to mess anything major up
 
340runnee said:
Yeah, I have actually read his series on it, and I've done a lot of research about rebuilding engines, I just want someone there who's a bit more experienced. If I mess something up it's gonna be expensive, so I dont want to mess anything major up
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I can completely understand. If I was local, I'd be glad to help. That'd be a commute from middle Georgia, though. lol
 
Wlecome to FABO. I'm also in Naperville. Not an engine builder, but glad to assist with your project if you just need an extra set of hands.

Pat
 
Divenut said:
Hey Dave! How've you been?
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Lol, slackin' as usual! How 'bout yourself?
Got a little around town road time in finally.
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Get a book and take your time it may take longert than you think . Cleaning stuff and measuring etc. is key. basically knowing what is go and no go
 
fix the leaks, check camshaft install for proper installed centerline while the cover is off, put a dual plane on it like an RPM/air gap and get the tune up right.

Even with lo comp pistons it should still move pretty good.

If an auto car, junky stock converter in it? Pull a plug or two, post a picture.
 
crackedback said:
fix the leaks, check camshaft install for proper installed centerline while the cover is off, put a dual plane on it like an RPM/air gap and get the tune up right.

Even with lo comp pistons it should still move pretty good.

If an auto car, junky stock converter in it?
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4 speed car, 4.56 on spool rear gears . It runs 96.6mph in 1/4, with crappy shifting and the 96.6 is with 3.55 and a limited slip, dont know what itll do now

Also have a nitrous kit i got used, I'd love to slap it on but id rather get everything nice before.
Also just a regasket wouldn't help the fact I'm burning a Lil bit of oil
 
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JMO, don't put juice on a poor running engine unless you want to hurt parts.

What intake, timing initial and total all in. Is this is a 71-74 B body? That mill should go in excess off 105 in an A body and probably closer to 110 if tuned well.
Smell like a fuel truck leaking gas on the road from the exhaust?
 
crackedback said:
JMO, don't put juice on a poor running engine unless you want to hurt parts.

What intake, timing initial and total all in. Is this is a 71-74 B body? That mill should go in excess off 105 in an A body and probably closer to 110 if tuned well.
Smell like a fuel truck leaking gas on the road from the exhaust?
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Thats where I'm at with the juice
Its a torker 2 intake, 22 degrees initial 36 all in
Yep, in a 71 roadrunner, weighs in at 3800 race weight with me but the runs were at over 4050, had a friend in the car helping me at the time.

Tune-up on the carb is good, doesn't smell rich really or anything, no lean bog when i step on the pedal, idles nice, but I just put on a new proform 750 double pumper and haven't put on enough miles to see how my jet tuning is via spark plug, and haven't had time to go to the strip, not to mention dont wanna piss oil on the line, and dont wanna chance running the same street over and over and over and over again to tune

If I'm gonna pull the motor to do timing cover and the heads for the valve seals which is the better way to do it probably, why wouldn't I at the same time just swap the pistons?
 
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Well as a update, I made a probably bad financial decision and snapped up a complete 1970 383HP that was originally in a 1970 roadrunner supposedly. Supposedly ran when pulled, has oil still in it and turns over. I guess now im gonna go through that instead or something, I dont even know what I'm doing with it yet. I hope I could get at least 400 horse out of it.
 
@Divenut your inbox is full, but here's what I was gonna say

Hi, saw your earlier post on my thread, and now would be the time to probably ask for help haha. I have a complete 383 in my Jeep Wrangler right now with honestly no idea how im going to get it out quite yet. It got in there with a forklift, and im thinking its gonna have to come out with cherry picker. Do you happen to have one?



Thanks,
Paul
 
340runnee said:
@Divenut your inbox is full, but here's what I was gonna say

Hi, saw your earlier post on my thread, and now would be the time to probably ask for help haha. I have a complete 383 in my Jeep Wrangler right now with honestly no idea how im going to get it out quite yet. It got in there with a forklift, and im thinking its gonna have to come out with cherry picker. Do you happen to have one?



Thanks,
Paul
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Hey Paul,

Unfortunately, I do not have a cherry picker. Sorry man :(

The wrangler build sounds awesome. Looking forward to hopefully meet you one of these days. There are a few great FABO members nearby.

Be well,
Pat
 
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