I've cleaned up most of the "off topic", trolling posts, back and forth bickering, out of this thread. I'd recommend some of our members here familiarize themselves with the forum rules before you receive sanctions that could result in your posting privileges being suspended or revoked. Attack ideas, not other forum members. If you don't have anything constructive to add to the thread that's on topic and intended to assist the OP, STAY OUT OF THE THREAD. CONSIDER THIS YOUR WARNING.

 

5 grams is pretty loose tolerance in this day and age of quality scales. I would have expected +- .5 grams. The 8 inch damper should help if you still have the original.

What Walter from Speed talk was mentioning is 'couple' and any good balancer will show that. The SW balancer had a switch to go from one to another and the magic was know what to do to fix an imbalance without creating a new one. The first 2 I balanced had spun rod bearing LOL nothing to hurt there.

If the engine every needs come out for a rebuild get someone to balance it that knows what they are doing.

Advancing the cam to fix the intake while interesting it only sort of get you what you need. If the cash and ambition available I would spring for the FIRST intake and be prepared to adding a bunch of fuel to the mid range and possibly keep an eye out for knock counts if running a bunch of timing.

 

.5 is probably what it was. To be frank, that was a figure I don't remember after 5 years. In general, the claim was to land better than factory tolerance. I don't have the original balancer anymore. Plus, it wouldn't work. My stroker is balanced with a 400 (external) damper. The factory 350 is internal on the nose. Also, I thought our factory balancers were 6 3/4"? Interesting, I did consider a swap in balancers to an ATI or something. That was also posted to SpeedTalk. IIRC, they weren't terribly convinced that would help. (I could try to dredge up that thread to confirm).

I also called Pro-Race to see if the damper could contribute (or if a better one would help)? They offered to let me call their expert who, IIRC, is in New Zealand or Australia. Rather than do that, I posted to SpeedTalk.


Sounds like you don't think my builder knew how to balance an RA correctly? I wasn't there during balancing so I don't know if/how they might have dealt with secondary vibrations. I would be interested to know what makes you think it's "wrong" and/or how you might characterize it's potential life-span.


Yeah...My designer was really pushing for the FIRST as well. And, I completely see the advantages of going that route. Of course, a swap to a superram wouldn't hurt either...especially if ported to the max.

My problem was starting with intake and header goals BEFORE ending up blowing the whole wad for a motor. I had already bought, polished, and ported an SLP TPI -- which took hours w/o a die grinder or bench wheel. Starting over with the FIRST represent lots of addition al work and potential cost. After going from a $3500 budget to the $8k-$9k range, I decided to get it back together and see where I was at.

My original, orginal PM was to a guy named Mick Stevens who used to be on this forum. He was (is) as good tuner and owned a 90 Corvette IIRC. I originally asked him how to build/improve MY car where it would have a lot more "guts" up to 4500 rpms -- especially in 3rd and/or 4th gear. I have gotten into my 50's and didn't need to build a race car to drive on the streets. I just like short torque blasts and to stay within the law.

Obviously, the FIRST would result in the best result. It would provide more headroom than the SLP TPI...and more torque. Oddly, I kept HOPING to see someone put one on a nice 383/396 build to see the results. It was kind of surprising that the people I kept seeing with plans to do so ended up not reaching their goals. I guess I should include myself in that group (to a certain degree).

I have to admit engine appearance was part of the allure. And HSR -- combined with my hi-rise hood has it's allure as well.

Again, this car is a grocery-getter that spends more time off the highway than on it. And, I've never gotten caught in the 1/4 mile itch. I would have built a different motor for that...and I didn't want to end up always feeling like I needed "more".

Building a motor and restoring a sportscar was more about the learning process, accomplishment, and pride. By my age, it's probably common to start feeling less like you need to get somewhere as fast as possible. Should I be corny and say slow down and smell the roses?!?!? LOL Ok...let's not. Hopefully, you will see my point in there somewhere.

 

I never suggested your guy did it wrong on the balance only what the guy at sped talk was explaining. Running warm is all the usual suspects in the cooling system. Fall is coming so limited drive time left. If it were me I would enjoy the car in the fall and do the cooling system things over the winter as I have to do with mine as well. I am tempted to change the rubber fuel lines as well. I heard E10 eats them up and a fire is not something to look forward to.

Bottom line is if you are having fun enjoy the car and don't worry about the HP left on the table if you seldom use it anyway. My '91 engine is stock at 250 HP and honestly don't care. If I wanted a faster car would have bought one. If I had been in your position I would have bought a GM 383 crate engine and a first intake and call it a day.

When I meant the original balancer I meant the one it was balanced with. Looking at all the drilling on the front throw I suspect he could have taken the counter weight out and saved a bunch of work. Another thought is do you have some super stiff race type engine mounts as they will rattle your fillings out.

 

Hi GreggPenn I also had a chip burned by M-Seven AKA Mick he knew his stuff.I'll be 66 this month so I feel the same way you do about not needing a race car.Just one that runs the way it's supposed to.One question for you how is your oil pressure from when you started running your 383 and now.That would be the best indicator of the condition of your engine.If its close to the same everything should be O.K.,If it has dropped significantly that would be an indication that the imbalance you feel is wearing away your bearings.

 

All right....HERE GOES!....

I'm with Amotoxracer. SELLC doesn't "Get it" w/regard to ignition timing, and the things he's saying are either incredibly misguided...or he's just having a very difficult time articulating himself. I don't know which.

I also agree w/Amoto that it is very unlikely that cam timing off by a few degrees would cause the overheating symptoms described. I too would look at more fundamental things.

If I was truly concerned or worried about my cam timing, I'd pull slap a degree wheel and dial indicator on there and see for my self.

Not really a field day, but that my .02.

 

The original balancer is still on the car. Not sure if/how I implied otherwise.

I asked the builder the same question (about removing the weight). Obviously, that's why I bought that style. When it came down to crunch time, he (his older partner) decided to leave it in -- so the balancer wouldn't be unique to the car. The removable weight couldn't completely be removed. He would have needed to mill it smaller.

Had they ASKED me, I'm not sure I would have disagreed. At the time I didn't know there could be the possibility of secondary harmonics that could be felt. Again, the builder had zero notion that there'd be any longterm effect in a street car. I'm certain he'd still oppose "internet guys" who think he didn't provide me a good engine.

It's almost 5 years old and the oil pressure is (unchanged) and still above factory levels. I used a hi-pressure oil pump. It's about 10 lbs above stock levels at all rpms. The engine has about 25k on it in that time. I don't know if this successful, protracted break-in period adds to prospects of longevity or not.

I have stock motor mounts. I'm not sure how to describe a vibration w/o it sounding like I'm talking worse than actual. The car doesn't rattle my teeth by a longshot. The first "harmonic" is around 1600 rpms. I spent hours trying to see if I could "tune that out". I did find that lower timing would smooth that region... You WOULD think multiple of that rpm (3200, 6400 would be noticable). I would say 3200 is pretty darn smooth. Oddly, the halfway point (4800 might be the only other spot it's detectable). Of course, I don't run the motor that high much...and especially not to 6400. So, the only goal was to eliminate that low vibration.

I'm only running cats and sidepipes. It's remarkably quiet for that config (but the sidepipes have internal curves and a baffle). I suspect most people wouldn't notice what I'm talking about if they drove it.

When I was done with the build, a forum friend showed up with his LT4. He helped with a few last minute details and I enjoyed meeting him (though he's since moved to Texas). The best thing that came out of that meeting (and comparison) was how STARK the difference is between street performance of my stroker versus his LT4. There was SO MUCH difference, it felt like I jumped to a 427 by comparison.

That's until you get them on the hwy and start pulling from 60mph. Obviously, in higher rpms, they are much more equivalent. I may only have landed 20-30rwhp more than an LT4. But, I have so much room "under the curve" that they are different cars. In that regard, it's really hard to be disappointed with my results. I got exactly what I hoped for when I contacted Mick back in 2007.

Third gear is as "fun" as 2nd. Fourth even has surprising torque (under the curve). As odd as it may sound to say it, 5th seems better than fourth USED to be. In short, it really IS a way better car than when I started. It would take a C6 (possibly an LS7) to tempt me to change. Since I'm in my glidepath to retirement, that might never happen. I don't think I ever saw a rwtq graph for a stock 89, but I've gotta think I'm around 75ft-lbs (or more) above stock in the rpms where I normally drive. That's why the motor feels so much bigger....like the 455 TA I used to own back in the 70s. But, the vette is a much better car.

I haven't heard the stories about E10 (or E15) being THAT harsh to eat our fuel lines. Obviously Jon (FIC) let us ALL know about E10 at the stock injectors...so I can see the connection in logic. Most of the fuel line is metal already but I guess there is one/two shorter sections where it's rubber. At least they are lower. As such, I'd never considered the threat of fire.

I WILL SAY, the threat of fire did occur to me when considering the modifications necessary to run a small-cap and reroute fuel lines for an HSR or a FIRST. That requirement did have a small effect on staying with the TPI. Not that I didn't trust myself...just the aftermarket parts I might pick.

A crate motor might have cost me more and I wouldn't have learned nearly as much. In that regard, I'm glad I built my own. If I could travel back in time, I might choose differently. Of course, I would need to land on the day I bought the AFRs and ordered them decked (to 54cc IIRC). Once I hit the need for dish pistons [in a 383], I was a lot further down the road to a custom block.

One final comment in this post:
When you wrote to "get someone to balance it that knows what they are doing", the implication was that my RA was balanced incorrectly....and the builder was a bad choice. Malik seemed to imply that as well. Others (@ speedtalk) told me not to worry. Having 25k miles helps with the later. If I knew it's longterm "prognosis" might not be stellar, I might be inclined to sell it earlier versus later and hop on the train to low emissions and bang the save-the-planet drum. When I compare the Kansas City NIGHT sky to when I was young, I can see a difference in the amount of stars you can see. On the occasion I'm further in the country at night, I look up so I can see them (clearly) again. In THAT REGARD, it's easy to believe we are contributing to a different future for our kids.

It's one thing I think of each time I see a new poster asking which route to take with a build. I thought of it myself. It had a bearing on my selections, use, and intent. I even tried the stock dual [front/rear] cat config. But, it turns out the belly cat couldn't stand up to the task/heat. That implied it might be too rich...though the tune and plugs say differently. The metallic bullet cats I used off the headers haven't failed in 5 yrs though. The belly cat that failed was ceramic. Magnaflow said it probably wasn't being rich that killed that ceramic model...more so the additional head put out by a 383...down the pipes. I didn't replace that ruined belly cat after hearing what it sounded like w/o it!

 

We are in agreement about your entire post. One thing I was wondering about -- when I posted my build pics on the last page -- is whether our forum builders can make any inferences based on the dial indicator/degree wheel orientation in the picture?

Obviously the alignment marks on the timing set are obscured but anything about cam orientation be inferred from that picture? (I'm guessing not...I assume the covers would need to be off while observing "rotating" valve movement).

FWIW, I called Bullet this morning and got my cam specs.
214 .544 intake, 215 .544 exhaust, 112LSA 108ICL
Events:
Intake open: -1 close 35
Exhaust open: 43 close -9

Because valve clearance was checked during the build, I'm having trouble figuring out what the potential worries might be left (from the potential of an effective 104ICL)?

IDLE heat is about the only discernible issue...though this thread seems to imply no additional heat would be generated (even if DCR were higher?) I think that might contribute (at idle)...in addition to thinner cylinder walls, heavier springs, 1.6 rockers, etc... As such, I have reason(s) to put behind the need for better fans.

 

Bottom line in the range of RPM this engine runs with a standard 50% balance it should not shake period.

Without reading pages of posts is this the one I have been following with turned down counter weights if so that is the problem. A balancing machine can eliminate the force and couple of the assembly somewhat static while not in operation though are spinning at a few hundred RPM. There was a procedure quite simple to do that did the calc for the operator. What it can't do is allow for dynamic operation with firing pulses. 18436572 43 same journal 65 same journal 57 next to each other... That is a job for the crank counter weights and damper. If this is not that thread disregard the though I just offered.

 

It wasn't clear whether you were saying anything "wrong" was done...other than the (questionable?) choice of drilling counterweights. Are my counterweights "turned down"? I didn't think so?

 

Different thread then..

 

If something was way off in your RA you would have defiantly found out by now with 25'000 miles on the clock.Your oil pressure being the same from day one to me is a very reassuring sign.A 383 with the parts you have is a great motor.I built my first 383 18 years ago.I did it the old school way 400 crank in a 350 block.World product sportsman heads it was a great engine.I put it in a 72 chevy Blazer.If your really concerned about your RA.drop the oil pan this winter and check to see what condition your bearings are in.I would venture to say they are fine.

 

I sent a text to my builder today. His response was any vibration/imbalance in an RA would be the same whether hot/cold. Since vibration has become more pronounced when cold (in the past few months), I guess that tells me it's not an RA balance issue.

I guess that means it's probably related to injectors and/or intake porting. My personal mechanic friend was voting that I pull the injectors. FIC could flow them if I wanted concrete measurements.

 

I doubt if porting it would be very hard to miss that bad at low speeds. Just start with unplugging one injector at a time and see if RPM is the same or very close for each cylinder. All the usual tune up things are always worth checking if it has 25k since build. I would not ne beyond checking valve lash to see if one or two has been too tight all along.