Ian Posted June 10, 2010 Share Posted June 10, 2010 Just a thought, I had it happen to me, but is there a port on the back side of the intake in the plenum, I had a team G intake with one and forgot to plug it when we put the engine in and it acted somewhat like that... Quote Link to comment Share on other sites More sharing options...
Heckeng Posted June 10, 2010 Share Posted June 10, 2010 Not the distributor tooth. Â How are your brakes? If a booster goes bad, it can turn into a constant large vacuum leak. Â The only missing under pressure sure sounds like a weak electrical connection to me, bad plug wire or plug. Make sure plugs are still seated firmly. Also, take an extra plug and make sure that the plug wires snap properly onto the plug end. There is a snap spring around the connector that can break off and cause a weak connection sometimes. Check the engine ground to the frame. Check the MSD ground and power supply. Coil like mentioned earlier could be bad. Â Â On the cam degreeing, while I am not doubting your ability or anything, it sure is hard to believe they would grind a cam that was 3-4 degrees off! That is horrible. If it were easy, I would want to try the cam as it was sent, without any adjustments--just to try. I would only try this if you knew you had enough p/v clearance though. I don't remember if you would need to advance the cam again, or retard it at this point. Quote Link to comment Share on other sites More sharing options...
Mike 57 Posted June 10, 2010 Share Posted June 10, 2010 Winston, what do the plugs look like? I would pull them and see if you can localize a cylinder Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted June 10, 2010 Author Share Posted June 10, 2010 Â Â On the cam degreeing, while I am not doubting your ability or anything, it sure is hard to believe they would grind a cam that was 3-4 degrees off! That is horrible. If it were easy, I would want to try the cam as it was sent, without any adjustments--just to try. I would only try this if you knew you had enough p/v clearance though. I don't remember if you would need to advance the cam again, or retard it at this point. Â I do not believe the cam was ground off at all. The difference, I feel, is in the chain set. The Hex-Adjust does not have multiple keyways to advance or retard the cam timing. It only has one way it can be installed. It uses a oblonged bushing that you turn with a hex wrench to adjust the timing. All I was saying is that when I lined up the bushing with the middle adjustment between A and R, which should be 'straight up' it came in off by a couple degrees. It's infinitely adjustable, so it wouldn't matter if it was off a half degree or 3 degrees, it's easy to correct, unlike most that have a straight, +4 or -4. (See below) I guess that's why we degree cams. I really didn't feel that it was a big deal at the time, I just put it in like it was suppose to be. Â Again, I do not think the cam was ground incorrectly what-so-ever. I believe the difference in cam timing is in the chain set. Â Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted June 10, 2010 Share Posted June 10, 2010 Justin, that's why I'm not a believer in that kind of stuff. Put in a stock type set and use an offset bushing if you think you need to advance it some. At least you would eliminate that piece of the puzzle. You need to remove as many variables as possible right now or you're not going to know what to chase...JMO...Dave... Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted June 10, 2010 Author Share Posted June 10, 2010 Here is what I did today, before I even started the car. Â Pulled all the plugs. They all looked great. I installed new ones anyway, gapped to .040 Â Unhooked the MSD 6AL and wired to run on distributor only. Â Changed coil to dist wire for a new one, only that wire. Â Took the car out for a spin and it ran good, no miss at all. Â Â Came back and put old coil wire on, still ran correctly. Â Hooked the MSD box back up, still ran correctly. Â So it looks like my issue was a bad spark plug.....again, these plugs looked great and showed no signs of trouble. I did pull them when I changed intakes, not sure if one was damaged somehow after that?? Â But the car runs well now and revs right up to the end of the tach. I set the timing to 36 degrees all in and hooked the vacuum advance back up. I still need to play with the carb a bit and I think I need to go to a 10 deg mechanical curve vs the 15 deg. I could use a bit more timing at idle to keep the vacuum up a little, it kind of wants to die at times. Â I can tell you from the little cruising I did tonight, when the 4 barrels kick in, you notice it big time. It's a totally different feel than the Edelbrock. A bit more tuning and it should be ready to hit the track again and see if it works.... Â Â Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted June 10, 2010 Share Posted June 10, 2010 well then forget all the other crap we told you!!! Â way to go Justin.... Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted June 10, 2010 Author Share Posted June 10, 2010 Would the vacumn line for the booster cause it? I'm not sure why the port on the intake wasn't used. Â With the Air Gap intake and the Holley carb, the bowl sits too low and you are not able to install a fitting in the manifold port. You must use the large port on the carburetor. I would bet the marketing people at Edelbrock did this on purpose. Quote Link to comment Share on other sites More sharing options...
BowtieThunder Posted June 10, 2010 Share Posted June 10, 2010 GREAT TO HEAR Glad you found it Quote Link to comment Share on other sites More sharing options...
Heckeng Posted June 10, 2010 Share Posted June 10, 2010 Edelbrock coincidentally sells a stubby 90 degree fitting that will work under a holley on their SBC intakes. I think you may have to use multiple or a thick carb gasket though. Â I understand how the timing set works but I would have though that when they were set on the middle setting, it should be neither advanced nor retarded--straight up, but you are saying it is not, and since you degreed your cam, you should be right. That is retarded of the timing set manufacturer though. Â Glad the miss seems to be solved! I hope the power is up where it should be now! Quote Link to comment Share on other sites More sharing options...
TN454Monte Posted June 10, 2010 Share Posted June 10, 2010 Glad to see you got the bugs worked out !! Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted June 23, 2010 Author Share Posted June 23, 2010 Still haven't been to the track, they were closed last weekend. But am planning to go this upcoming one. Â I wanted to put on a 1" open spacer to help on the top end, but as most of you know the room is somewhat limited under a stock hood. I was running a 1" drop base air cleaner, I think it was a K&N base. I could fit a 4" element without the spacer, it's tight but it does work. Â Didn't want to use a 3", my calculations showed it didnt flow enough for my setup. So....in order to stick with a 4" filter I needed a new air cleaner base. I ordered a factory GM L-88 Corvette drop base. GM used this on several combos when they had a high rise intake and a Holley carb. It is suppose to be the best flowing drop base ever made. It is actually molded around the Holley carbs that came on the L88 and LT1's. Â I did have to notch it a bit where there was some alignment tabs, and I also needed to remove the PCV air inlet pipe as it hit the rear accelerator pump. Â It looks like it will work great. It drops the filter 2" below the carb top and flows around it beautifully. Â Â Â Â Â Quote Link to comment Share on other sites More sharing options...
wallaby Posted June 23, 2010 Share Posted June 23, 2010 Those are a very nice piece. I never figured out why the aftermarket didn't catch on and start stamping those out. Where did you get it? Quote Link to comment Share on other sites More sharing options...
TN454Monte Posted June 23, 2010 Share Posted June 23, 2010 Nice looking set up... Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted June 24, 2010 Author Share Posted June 24, 2010 I got it from Corvette Central. Â Description ALL 396 427 EXCLUDING 3X2, L88, LT1 Corvette Central #: 152088 Original GM #: 6422188 Car years: 1966, 1967, 1968, 1969, 1970, 1971, 1972 Â I did alot of research and this seems to be the best one made. The way the air flows over the air bleeds into the horns is suppose to be better than any other air cleaner base. Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted June 27, 2010 Author Share Posted June 27, 2010 Got to the track today. First time I had ever driven my car and not trailered it. Ran great all the way out there. First pass I spun pretty good out of the hole, ran a 12.0 at 115.8 Â Bumped up the timing a bit for the second run. Still not a great hole shot, but felt like a good run. Got to the probably the 1000 ft mark (guessing by the video playback) and the car just fell on it's face. I actually thought I blew a tire. Â Turns out the driveshaft snapped and decided to remove itself from the car. It twisted apart towards the rear of the car acutally. The stub swung around, still connected to the rear end and hammered my new mufflers and the bottom of the car before the u-joint retainers on the pinion gave way. In the mean time the front half of the driveshaft came out of the tailshaft and bounced down the track. I guess that's why they make you put in a loop... Â Whilst all that was happening, a flum of white smoke poured out the car as the transmission case cracked in half just behind the bellhousing and put oil all over the car and track..... Â Like I said, this is the only time I had ever driven to the track. My old man had my trailer 300 miles away, so a trusted friend had to rent a trailer and make the 2 hour trip to get me. I have had better days. But the car is MPH'ing 115+ now, so the changes I made with the carb and intake helped, but I didn't get a chance to do much jetting. Â What would cause the case to crack like it did? See pics below. Â Â Â Â Â Â Â Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted June 27, 2010 Share Posted June 27, 2010 the exact! happened to my buddy thirty years ago my guess is the shock of the shaft letting go snapped the tranny case  Quote Link to comment Share on other sites More sharing options...
72MC Posted June 27, 2010 Share Posted June 27, 2010 Man I hate to see any kind of parts failure. Time to call Denny's. - Dave Quote Link to comment Share on other sites More sharing options...
wallaby Posted June 27, 2010 Share Posted June 27, 2010 Just imagine the forces that poor thing underwent. You were at full throttle and the shaft let go, so instantly it was out of ballance and whipping up to redline or above. That kind of force can tear up all kinds of stuff. Â I'd be more embarassed about the mess I left on the track. Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted June 27, 2010 Author Share Posted June 27, 2010 It blew at near the end of the track, so it didn't make "too" bad of a mess. We had alot of cars muck up the track today. More time cleaning than people going down it, unfortunately. I got pulled off way to the side right away, like I said I thought I had a puffed tire so I tried to get if off the track. The majority of the oil leaked out while I was waiting for the tow. I talked to the guy I was racing against, he had a brand new Corvette. Said he was pretty nervous when the driveshaft came out from the car. Below is the video of the run. You can hear when it breaks and it bops the rev limiter (7k). Keep in mind I'm doing 110+ when it happens, as I still ran a 12.1 @ 108mph. Got it shut down pretty quick. Â Sorry about the bad camera, it seemed to have moved at the take off. Â Â Â Quote Link to comment Share on other sites More sharing options...
Heckeng Posted June 27, 2010 Share Posted June 27, 2010 I'd guess the driveshaft caused the tranny case to break, but if you have all solid motor and tranny mounts, that can cause cases to break too if the motor has enough torque. The frame will flex but the engine and tranny can't give because the mounts are solid, so the tranny case at the bell housing is the weak point. Â Sorry to hear about the break, but the 12.0 is nice! Quote Link to comment Share on other sites More sharing options...
502ci Posted June 27, 2010 Share Posted June 27, 2010 Your mufflers are toast also. Not sure what series u-joints you have but I would look into the 1350 series. I myself have them as well as a 3 1/2" aluminum driveshaft from Moser...we are running similiar times, what axles are you running as they probably are the next weakest link? Quote Link to comment Share on other sites More sharing options...
TN454Monte Posted June 27, 2010 Share Posted June 27, 2010 Sorry to hear the shaft let go like that...but glad you're okay, it could have been much worse. Quote Link to comment Share on other sites More sharing options...
Chevyss Posted June 27, 2010 Share Posted June 27, 2010 My biggest fear is breaking a drive shaft. Denny's ready to go in with a loop. Glad you are OK. Parts can be replaced, legs can't. Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted June 27, 2010 Share Posted June 27, 2010 Justin, have I ever talked to you about exceeding critical driveshaft rpm's?? Â Â Happened to me at the first of the year, of course like you it was the first time at a new higher speed. Same results as you except I didn't know I had cracked the trans case until I changed converters a couple of months later. Mine cracked in the bellhousing area.... Â I think you know what to do.....sorry it happened...scared the crap out of me...same thing just before the stripe at 120.... Quote Link to comment Share on other sites More sharing options...
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