Hey all.... As most of you know, I've been fighting a head gasket grimlin. I have since ordered up some 4ply cometics .074 thick. Cometic stats that a retorque isn't required (doesn't need to be done). However, I've hear various oppinions about retorquing them even tho the manufacture says not to. My question is this, A. Is anyone out there really putting the cometic's to the test right now? If so did you retorque them? B. If you are retorqing them, is it done Hot (after it's ran), or over time like the TA's Orange Crush? I should have my gaskets Wed's or Thurs this week.... I'm hoping to have all my ducks in a role so I don't have to loose out on any more car season :Brow: Thanks for the input
Rich, Without getting into a long explanation right now. I feel a retorque is an ounce of prevention. A quick recap: The BBC with low boost (8#) did just fine gasket related. The SBB with big boost (we were at 15#) lifted the heads and blew out. BUT!!! The gaskets (we paid $230 for these special) were not hurt and are going to be used again. WITH STUDS THIS TIME!!! PS. You and JB are gonna s_it when you see the graph. Later.
Hey Bill, Where the gaskets cometic's? Also do you feel pre fire retorque is good enough? I'm sure you know but AC cars are about impossible to do a head torque with the motor in the car. Send the graph........ enough of the teasing already :grin:
Rich, Sorry I haven't been able to sit on the pc for any amount of time. Yes, the gaskets were cometics. The "locals" that are playing with these two engines recomend a retorque after the initial run regardless what they say about the gaskets. Take this as necessary because these builders know what they are talking about. (I'll get into this at a later time.)
Rich I have about 20-25 runs on my Car so far this year after switching to the Cometics on my 13.4:1 505.... No re-torque......No problems....... I went with their advice on this,and so far so good.
Hey Gary, Thanks for the info. Just curious if your using heads with the extra bolt's? I think I may retorque them before firing the motor up while it's still out of the car. It's such a #$@#! to access the head bolts on a air car that I'm not sure it would be worth it.........
Rich Yes I do have the xtra 4 bolts.......Wouldn't be a bad idea to loosen and re-torque 1 by 1 after the initial torque. You see what I mean when you put them on,But they are unlike any other gasket to torque.....as you go through the sequence and they compress,It is evident.
We retorqued ours after the first night of racing, just because we're chicken I guess. 13.25-1, iron heads, studs, methanol, 6500rpm, 3 nights on high banked dirt oval. No problems yet.
Rich, There are differeing opinions on this whole retorque thing, but my understanding is that you have to retorque the heads no matter what. The point of the retorque (and the torque down) is to maintain clamping force. The gasket doesn't really help or hinder the clamping force, only the head bolts/studs. The bolts stretch with time when under load, when they do this they lose thier clamping force. That's why you have to retorque after 3-4 days, the botls stretch (engineers call it Creep). The head gasket doesn't help with the seal in that case unless the engine blows a hole in the gasket ring. Could be wrong, just my 0.02.
Thanks Clint, I just wonder how much studs that have already been used will stretch.......... At this point, I'm planing on doing a retorque...... I'm just not 100% sold on doing one the car has fired. I may let the motor sit for a few days out of the car and do a retorqe before setting it in... That is unless others feel it's necessary to do it after a few heat cycles........
