Hey there guys. I’m a new member and this will be my first post. I just came into a 79 Chevy pickup with a 250. Now, I like to think I’m pretty proficient with vehicles, but I have never rebuilt an engine before. So, I have quite a few questions I would like the pros to answer. I have done a considerable homework on this, but there seems to be contradictory schools of thought here on what should be done with the engine and so forth. Also, I own a truck, so I don’t know if it would be that different from the usual car applications that I see on the forum. Anyway my question is what I should do with the engine to get a good amount of torque without having to sacrifice reliability or having to constantly fill it up with premium gas (high compression) as this will be my daily driver. For instance, is going .030 over the biggest I want to go on the bore without having heat issues? Would I really have to shave .060 from the head as Clifford Performance says? That seems like an awful lot to me. Would I need to -0- deck the block if I’m using flat top pistons? Sorry this post is so long; I just have a lot of questions so any help you guys could give me would be awesome. Thanks a lot guys
-J

Welcome to the Inliners BRD.

Keep in mind this BRD is provided by Inliners paying members, but you are still more than welcome to use it.

There is a membership form called SIGN UP on the left sign of screen.

With your engine consider .060 a safe maximum overbore.

Zero decking the 250 with flat tops is a good thing to do. Shaving .060 from the head is alot in my mind. Most of my heads get shaved .030 and some get more.

Lumps added to the head intake ports will certainly help wake the motor up and not sacrifice any streetability.

Back to dyno work. Tom

I am no pro though,,,but here are my thoughs,,,

You can also add a water/methanol kit for normally aspirated engines so you dont have to run premiun fuel.

Zero deck the block.

A camshaft w/about 204 degrees duration @ .050 will work nicely.

Lumps added.

Remember,,,when you get flat top,,make sure they are flat tops,,no chamfers on the top side ,,,no recessed areas other than the valve reliefs..

MBHD

thanks for the welcome and all your help. so .060 would be safe as a daily driver? i'm impressed. what source do you guys use to get your parts? (pistons, lump, etc) also, i've read a few times that we shouldn't port and polish the head. what is the general consensus on this as i have also read that a lot of people have done this.

Hey justnwynn, there is currently a thorough dyno test being conducted this weekend in another post that is answering many misconceptions in those areas. It has already been determined that the installation of the lumps, does dramatically improve the airflow and HP of these engines throughout the entire operating RPM range. So that idea of not to do it, is definately one of those misconceptions. Keep watching the post of this dyno testing, and im sure it will further answer other questions you have about how to properly modify and improve your current inline project.

Justnwynn-

Welcome to the Inliners Bulletin Board.
You can find a lot of info and ideas here - BUT

tlowe has a good point. By joining Inliners you can support this website, but more importantly, you can meet some of the greatest people in motorsports.There are Chapters all over the world with local events and the club has a convention every two years.

Hope to see you.

Will Willis
High Plains Chapter Head

i do plan on giving money to the organization.. its just that i stumbled upon your site about a week ago and i am offshore in the gulf of mexico (working) without a way to pay untill friday. if its considered bad form.. i could stop asking questions untill i can pay.. either way.. the info on this site has been invaluable to me as i'm sure it has to others and i cant thank you all enough for the time you took to answer my questions. (i will have others i'm sure
-J

J, pump that oil...we need it!

And welcome. I joined Inliners a number of years ago, have attended a couple of the conventions and have enjoyed every minute of it. Join when you can and keep asking!

justnwynn-

There are a lot of Bulletin Board only members who are a big part of this website and all are welcome.

Joining the club just gives people a much fuller experience.



Will Willis