see, i go by what the guys that do this for a living say. when they have the amount of builds, that they do, under their belt, i tend to belive them. none of these measurements were decided on by me. lord knows i don't have a engineering degree, they have or the experience they have. bubba do you get paid to assemble motors for a living? and if so do you run the shop and come up with the clearance numbers or just listen to another person? as far as the clay measuing style. its just like evey other type of checking we can do without the motor running. its just a ball park figure of clearance. thanks for all the input gents

 

Higher compression on a stock engine, a thinner head gasket is a cheap way to bump up compression + improve the quench on an engine that is otherwise stock. So you end up with a more efficient burn from a two fold effect one from the higher compression and the improved quench. Since the stock quench is anywhere from .071 to .088 swapping to the thinner impala gasket will yield a quench anywhere from .048 to .061 still well within the safe range for these engines what is there to lose by swapping to a thinner gasket? Its obvious what you have to gain on a stock engine.

 

Hey, just sayin'. No I don't build engines for a living nor would anyone want an engine that I built. So tell me how much HP/TQ would one get by using this thinner gasket? Is using a thinner gasktet the thing one would want to do with an aluminum head which might be more prone to blowing the gasket. The idea of the gasket is to insure a tight seal between the head and the block/cylinders. If you didn't use any gasket you would not have a seal--heads and blocks are not always perfect, thus the factory specs regarding gasket thickness.

Does the manufacturer build in greater margins for safety----absolutely. Is it possible to increase power by reducing the margins----of course. Is it somewhat risky to reduce all of the factory engineers' margins to gain more power---might be----depends on the gain vs the risk.

Don't know much about nothin' when it comes to cars. I just buym' and drivem'. Not that I don't like the idea of making more power or having someone help me (or do it for me)but....I have had plenty of experience with the results of mechanics, engineers, manufacturers, etal when it comes to cars breaking down for some reason or another and I don't find it particularly enjoyable when it happens---especially from a $$$ point of view or just plain inconvenience.

However I do find it amusing to read time and time again where someone is going to use, or do something questionable or perhaps a teensy bit risky for a novice when some things have been pretty much accepted among owners on this site, eg. using NGK plugs instead of bosch 4s, 1" header bolts, felpro gaskets, no messing with the maf, stonger valve springs, care in installing cams, not spending too much time on which oil to use, putting in humongous cams, especially in a stock bottom, aggressive launches with a 10 bolt-----you all know what I'm talking about.

If you knew me as well as most on this site, you wouldn't put much stock in my opinions. I'm just glad I'm allowed to be on this site.

 

lol i am basiclly in the same boat as you. they got into issues that reminded me of a old song "things that make ya go humph" or however that went. i was just wondering if you had a background in that field or what, i wasen't trying to be a SA . even though thats what i am best at. i'll let ya know how she does. shoundn't be long at all. (god i keep saying that and keep hitting more set backs)

 

I wouldn't put the optimization of quench in the same category, but I know where you're coming from. Yeah, if I were assembling this thing, things would be way off on the safe side, but I like many others, are looking to make things right (or better) where we can - my engine builder has been to this rodeo a few times so I trust his ability and opinion. Yeah, I know Rich and a few others debate this pretty vigorously, but there are more fast guys who are not on this site doing this than those who pretent to be fast not doing it.

 

I sure hope you are not referring to me as the person who is trying to be "different". I was the skeptical one the entire time when I heard of a "thinner" head gasket which Is why I posted here.

 

on a side note , did you have any issues with t56rebuilds.com? (now know as 6speedsinc.com) pm me if you feel the need to keep it private.

 

Actually T56Rebuilds.com was Amazing. The best customer support I've ever seen. They happened to be at a track near me and they let me drop off the trans there, then they had it shipped back after a few days(so i paid no shipping at all). My trans was destroyed pretty good and it only cost about $1500. Then when I got the trans installed I had a problem w/ the clutch not disengaging so I called them up and they helped me out as much as possible, even letting me talk to their driver about it and she went out of here way to ask other local shops about the problem. In the end it turned out that the clutch was defective and too thick! They were ready to ship me an adjustable master just to see if that helped.

Overall If I had to do it again I'd go with them.

The only thing I noticed was a slight wine in 2nd gear but hardly anything and probably normal.

 

wow, long story short . i ordered the tranny in april and received it 3 times (they swore dhl had it) finally they said they dropped the ball and figured out they never made it. made it shipped it , then i noticed i had me a nice t56 for a LS1 car, lol i ordered it for a lt1. then i got the lt1 version and shipped the ls1 version to a guy in maryland. sad thing was i ordered the 2250. package and it took 3 months of untruths and blaming dhl to get my tranny. glad you had a good dealing with them, atleast they finally got mine right. have you figured out which gasket (from this post) you are going to run yet? good luck man and thanks for the info on six speeds inc.

 

from impala head gaskets, to quench, to t56 rebuilds. this thread has taken a journey.

 

I'd like to see this answered. Then the risk versus reward is a better judgment call.

Dan

 

I've been sitting in the wings, reading and waiting to see where all this
is going. I'll be swapping heads on a stock motor one of these days and
the plan is to go with the Impy head gaskets. I would not think the shop
doing the heads would recommend something that will not work or would
lead to future problems. They do this all the time and there are probably
100s of LT1s running the Impy gaskets with aluminum heads.

I'd also like to see the answer to the HP/TQ question on a stock motor
with just a head gasket swap.

 

I'm pretty sure Im going to stick w/ the felpros. No one seems to have any proof of hp/tq gain from the impala's. Plus the idea of having a thicker gasket makes me feel better.

On a side note, I bought some felpros a while ago and when I got them they were botha bit bent on the corner(s) from shipping. There is a mark where It was bent but Would this effect anythig when I bolt it down?

 

You're looking at about a 1-2% average gain in torque across the rpm range of the engine from the increased compression.

 

I have no problem using the Impala gasket to raise the CR, if that is desired. But you must not put the piston too close to the head. I would not use a 0.029" gasket on a zero deck block - it is too close.

Rich