1975 Plastic fantastic aka Corvette

[Scott Liggett]

Scott - I'm not a pro, I can only relate what's either happened to me; or what was told to me by someone I should have probably listened to. As I told you before, you mileage may vary.

In any case, I'd be the highest order of jerk if I didn't mention this to you now...

I didn't go into to this lightly or without thought. I have a studded 350 four bolt in my car now that I could buy forged bottom end parts. With the billet splayed main caps and the short fill, these will hold for what I want power and boost wise. I am not going for 1000 hp and 20 lbs of boost by any means.

[SuperBuickGuy]

It's a little hard to blame your 400's demise solely on boost when you said it had an intake leak and a bolt bouncing around the crankcase. But, I will look into it.

Scott - I'm not a pro, I can only relate what's either happened to me; or what was told to me by someone I should have probably listened to. As I told you before, you mileage may vary.

In any case, I'd be the highest order of jerk if I didn't mention this to you now...

[Scott Liggett]

It's a little hard to blame your 400's demise solely on boost when you said it had an intake leak and a bolt bouncing around the crankcase. But, I will look into it.

[SuperBuickGuy]

decisions, decisions.

I feel like I've pulled this transmission as many times as Randal has changed cams...

problem 1
the pressure plate is riding too close to the inside edge


problem 2
why did they chamfer this hole? how do you get an accurate measurement for the depth? at this point, I think the throwout is 1/4" too close to the pressure plate (about the same dimension as the chamfer


problem 3 it's leaking - which could be the cause total of the problem with slippage


Interestingly, neither Speedway nor McLeod list this bearing for the Super T-10 anymore.... and the one they do list now is $317.00 and will not be shipped until the day after the track day (11/18)

square instead of chamfer



so what to do.... I might be able to switch to manual actuation if I pay huge bucks for next-day air for the parts... it also means I have to pull the entire dash out to replace the pin on the clutch pedal (had to remove it for the hydraulic system, naturally).....

I'm at a loss.... I think I have enough parts here to put the transmission back in the car with the clutch arm, pivot, and non-hydraulic throwout.... presuming the clutch pad isn't toast because of hydraulic fluid....

of perhaps buy a hydraulic slave cylinder that mounts to the outside of the bellhousing. I have a bellhousing would work, but I'd lose the scattershield (not optimal, but a possibility)....

[SuperBuickGuy]

there was a vacuum leak under the intake manifold that precipitated the destruction, but yep - bad day.

[Deaf Bob]

Looks like boosting 400's is a bad idea!
That's rough!
The siamesed bores really do not like heat!

[SuperBuickGuy]

I'm simply going to hit the surfaces with a disk and figure out why that stupid hydraulic throwout is too close....

first a reminder of a potential problem with boosting SBC 400s .... I needed to pull the motor out to steal its pan




why can't it ever be easy? stupid bolt


interesting, there was a 1/4 bolt floating around in the pan. I have no idea where it came from.... ah well


nice and clean... once the glue dries it'll be ready to go up - note the edge scraper, and the much better baffles?



cheap ass Taiwanese pan

[yellomalibu]

Next weekend, Sunday, open track day for the Corvette..... I think I found the issue with the EFI, so it stays until after the track day. However, I need to pull the transmission again and make sure the clutch is happy. While I'm at it, I'll swap oil pans to rid myself of the leak around the drain plug and put a well-baffled pan in its place.

What are the signs of an unhappy clutch? Signs of slipping? Hot spots on the flywheel?

...and I'm guessing "open track day" is for a road course not a drag strip - but still, if you have to change any clutch parts, will you have enough time to break in the new parts before beating on them?

[SuperBuickGuy]

Evergreen speedway?

Pacific

[Deaf Bob]

Next weekend, Sunday, open track day for the Corvette..... I think I found the issue with the EFI, so it stays until after the track day. However, I need to pull the transmission again and make sure the clutch is happy. While I'm at it, I'll swap oil pans to rid myself of the leak around the drain plug and put a well-baffled pan in its place.

Evergreen speedway?

[SuperBuickGuy]

Next weekend, Sunday, open track day for the Corvette..... I think I found the issue with the EFI, so it stays until after the track day. However, I need to pull the transmission again and make sure the clutch is happy. While I'm at it, I'll swap oil pans to rid myself of the leak around the drain plug and put a well-baffled pan in its place.

[TheSilverBuick]

Yup, scavenging fuel parts. I'm leaving the MegaSquirt and wiring in place though. Will probably actually wire it up to control timing as I think a VR distributor came with the barn that will work for a trigger and locked distributor. That way I don't have to back the timing off when I drive off this hill or on hot days, it'd do it automatically.

[BBR]

Retrograding. I dig it. Randal just did it to the tbird.

[SuperBuickGuy]

that's it... this car is a knuckle dragging car, and I can use the EZ EFI on other projects..... I'm putting a carburetor back on it.

[SuperBuickGuy]

there are days I wonder why I changed to EFI (days when I go around a corner aren't those days)... however, the O2 sensor says I'm running at 15.9 a/f ratio. I checked the regulator and I'm at 45 psi fuel and maintains that pressure when you bring the idle up.... Also, resetting the fuel pressure (it was low initially) did get it off 15.9.... by racing the motor (getting off the idle circuit, it will blow black smoke) computer is set to 14.3 cruise, 12.3 WOT, 13.7 idle.

I'll update as I figure out what's up

and yes, it's running lean (and yes, I put fuel in it to be certain I'm not picking up air).