What is a 355?
Perhaps someone could take the time and explain this to me in layman's terms?
I bought my dream car - my Formula LT1 - because I wanted something to tinker with and spend some time on, and after countless hours (years) of browsing I think I have finally found what I would like to do with it, and that is to build a 355! I'm not talking about starting this build today, but somewhere down the line I would like to do it. For now I would just like to know what a 355 is and what you need for it. All info is appreciated!
I have zero experience of any kind of engine work and I haven't done anything like this before (well, I did Pacesetter LT's last year lol), but I bought this car with the intent of learning. My car is my hobby and I have been a car guy for as long as I can remember. Cars in general, and f-body's in particular is my life!
Looking forward to answers!
/E
Last edited by ErikFormula; Apr 19, 2017 at 03:55 AM.
This means the diameter of the cylinder bore is 4.00" and the amount the piston travels up and down the cylinder is 3.480". A 355 is when you remove 0.030" from the cylinder walls for a rebuild but still retain the stock length of stroke. A 383 is when you remove the 0.030" from the cylinder walls but also change the crank to one that has a stroke of 3.750".
the reason why you don't see 355 kits really is because it just requires a larger diameter piston where as a 383 requires different pistons, rods, and crank.
This means the diameter of the cylinder bore is 4.00" and the amount the piston travels up and down the cylinder is 3.480". A 355 is when you remove 0.030" from the cylinder walls for a rebuild but still retain the stock length of stroke. A 383 is when you remove the 0.030" from the cylinder walls but also change the crank to one that has a stroke of 3.750".
the reason why you don't see 355 kits really is because it just requires a larger diameter piston where as a 383 requires different pistons, rods, and crank.
cubic inches increase the potential for power since more space inside the cylinder can equal more power with the proper compression ratio and supporting parts like a larger camshaft and better flowing cylinder heads. Changing the piston allows you to run a different design to influence the compression ratio like more compression for a naturally aspirated build or one using higher octane fuel or lowering the compression ratio for forced induction.
cubic inches increase the potential for power since more space inside the cylinder can equal more power with the proper compression ratio and supporting parts like a larger camshaft and better flowing cylinder heads. Changing the piston allows you to run a different design to influence the compression ratio like more compression for a naturally aspirated build or one using higher octane fuel or lowering the compression ratio for forced induction.
So if I buy a LT1 rebuild kit with a new crank and some new larger (forged?) pistons, and a mail order tune, is that all I need? My car has 77k miles on the clock btw.
How much money are we talking about?
https://play.google.com/store/books/...FRZHDAodObYCoQ
Read it a few times, then start planning a motor build.
https://play.google.com/store/books/...FRZHDAodObYCoQ
Read it a few times, then start planning a motor build.
Trending Topics
The Best V8 Stories One Small Block at Time
After doing the LT's I swore that next time I do anything I will pull the engine, and if I do that I might as well give the block some love while it's out in the open. Thinking about it still gives me chills along my spine.. it took me 6 weeks to do the headers, not one weekend as the people here on the forum said lol!
Thank you for your answer, I will search eBay for a shop manual!
First of all I'm gonna build the rest of my exhaust, and when that is done I will move on with the suspension (probably Koni STR.T or KYB AGX). After that I will move on with the body and rims. I'm about to be a father in a few months so the car is pretty far down on the list. ^^
Anyway, thanks a lot for the help, and btw your car is badass!
When looking at rotating assemblies stay away from cast cranks unless using a GM crank. Hypereutectic pistons are fine unless you're planing a lot of compression, forced induction (turbo/supercharger), or nitrous.
Doing a heads/cam swap will gain you alot of valuable experience in disassembly/re-assembly and how the motor goes together. Depending on the setup, you should end up between 350-400rwhp realistically, which will equate to a fun street car. Once you get bored with that, figure out the next steps. Some people move on to nitrous or forced induction (supercharger or turbo).
At that point, start considering what bottom end to run.
When looking at rotating assemblies stay away from cast cranks unless using a GM crank. Hypereutectic pistons are fine unless you're planing a lot of compression, forced induction (turbo/supercharger), or nitrous.
Doing a heads/cam swap will gain you alot of valuable experience in disassembly/re-assembly and how the motor goes together. Depending on the setup, you should end up between 350-400rwhp realistically, which will equate to a fun street car. Once you get bored with that, figure out the next steps. Some people move on to nitrous or forced induction (supercharger or turbo).
At that point, start considering what bottom end to run.
I forgot to mention that I live in northern Sweden so ordering parts are very expensive with import charges and all that. My Pacesetter LT's and y-pipe sat me back close to 500 bucks in additional charges.






