Big increase in power in my 1977 403ci engine

[david j. forjan]

Ken and MIke's point about possible damage to the tranny is not lost on me. 1500 miles so far so good. If and when I have tranny problems or need to
replace it I will post that here, for education and in the interest of proper scientific experimentation methodology.
Thanks for that insight both of you.
Be well.
david
--
David J. Forjan, 1977 403 26' Palm Beach, glad to have the 3.70 Final Drive and pork chop for level front end, Tularosa New Mexico

 

[roy keen]

Besides gearing recurving the distributor by increasing mechanical advance at a lower rpm and reducing vacuum advance at the same time is one of the
most rewarding improvements that is inexpensive and very noticible in most cases.
--
Roy Keen
Minden,NV
76 X Glenbrook

 

[Keith V]

David Said;
"As for getting more out
of a design, doesn't dual exhaust or quad exhaust or headers or turbocharging get more out of the original design? Significantly more too? "

Then you've changed the design

 

[mike sadlon]

David and Rick,

I always try to give credit were credit is due.

After your thread the other day, it really got me thinking, why did my transmission go and not yours?

End of every old school tune up I have ever done in my 40 years working on engines. I always check for spark knock with a quick power brake full load.


Of the 2 previous trans I killed, I thought I knew why both went. 1 was old, and the other, the guy, in the car had it in reverse. Bad scene on a new
trans and engine.

I knew my trans in the coach had been replaced at lest once because it had a switch pitch converter.
I always keep my trans in high stall except on the hiway. I like the way it accelerates.
After looking at dyno chart after dyno chart lately, It hit me.
So as I did my tune, the motor was 500 rpms up the torque curve. Making probably 100 lbs more than a normal pull.
So one slipped transmission.

So as your read todays thread "balance your system", you can take credit for me thinking about torque converter upgrades or run and hide. :]

It's an area for improvement I think we may have ben missing.

Thanks, Mike

 

[david j. forjan]

Thank you Mike for the nice words and insights. And now you got me even more fascinated with this subject. I have two questions if you have the
time. What do you mean by "high stall". And are you recommending torque converter upgrade?
Thanks Mike.
Be well. David
--
David J. Forjan, 1977 403 26' Palm Beach, glad to have the 3.70 Final Drive and pork chop for level front end, Tularosa New Mexico

 

[mike sadlon]

David,

You get a minute read the 'balance" thread from yesterday.

When Rick floored it while braking, the RPM the motor was at was near the stall speed.

There are all kinds of stall speeds available. They should be chosen to balance the application.

I think GM had to go with what they had it 1973. We now have options.

I try not to "recommend" anything. Just put out knowledge to share.

But if your a customer, we will probably do what I think is best.

Mike

 

[david j. forjan]

Hey Mike I apologize for taking this long to say thank you. Thanks for your insights and experience. Every little bit of information helps alot. I
read the "balance" thread and I understand on a conceptual level, but that's it. Helpful nonetheless. Be well. david
--
David J. Forjan, 1977 403 26' Palm Beach, glad to have the 3.70 Final Drive and pork chop for level front end, Tularosa New Mexico