More Power for LA360 Engine

[Lemon_Belve]

Hello
I am the new one from Germany.
I am shortly before to buy a beautiful 67 Belvedere II with a 72 LA360 engine.

The engine was Build in the past with some Upgrades but I want some more Power.

The actual Specs:
Indy heads: 360-H1-LAX, 1,920 und 1,625 inch valves
Cam: Mopar Performance: pn P4452782, camshaft and lifter kit, for idle 5800 rpm.
Edelbrock performer manifold with Edelbrock Performer carb 1406 - 600 cfm.

Now my Plan is to Upgrade the Pistons for a Higher compression rate without boring of the Block and TTi Headers
Is it possible to build the engine with kb107 Pistons with 4.000 bore to get the higher compression Rate?

Best regards
André

 

[69Bee]

Welcome from AZ...

 

[RemCharger]

One must ask themselves;
Will the new piston rings slam into the ring ridge of the bore from the old completely different pistons..

And welcome from Sask

 

[Lemon_Belve]

Hello
My expectation will be that I have a Standard 4.00 bore and put new KB 232 Pistons with also Standard 4.00 bore into the engine.
Or what do you mean?
In Combination with the 62cc Indy heads it will be a 9.5 compression.
With the kb107 Pistons it will be 10.9 and In dont know if this is not to much for the engine. We have 102 octane Gas in Germany but In want a healthy powerful engine.

Best regards
André

 

[hunt2elk]

Since you are taking the motor apart already, have you looked into doing a 408 stroker? More money than just changing pistons I know, but then you would have a real nice upgrade with a better compression ratio. Throw a 750 carb on top and call it a day.

 

[rumblefish360]

The actual Specs:
Indy heads: 360-H1-LAX, 1,920 und 1,625 inch valves
Cam: Mopar Performance: pn P4452782, camshaft and lifter kit, for idle 5800 rpm.
Edelbrock performer manifold with Edelbrock Performer carb 1406 - 600 cfm.

That is the original stock camshaft.
This engine should perform like a stock engine of years past. Plenty of room for upgrades.

Now my Plan is to Upgrade the Pistons for a Higher compression rate without boring of the Block and TTi Headers
Is it possible to build the engine with kb107 Pistons with 4.000 bore to get the higher compression Rate?

Yes it is possible. If the cylinder bores are not worn out. A light hone to address the cylinder surface will prep the cylinder walls for the new rings. Above, someone made a mention to the ridge that could be left behind from the current pistons and rings. If honing the cylinders do not take craw of the ridge safely for a stock sized 4.00 piston, then you’ll need to go to the next size available. This is normally a size of an extra .030 of an inch. BUT do so look to see if you can get the piston in a smaller oversize. .010 or .020.

Let you machinist decide the bore size before ordering pistons. Also, the amount a block can take in being bored is decided with a sonic check to see what the cylinders wall thickness is.

Hello
My expectation will be that I have a Standard 4.00 bore and put new KB 232 Pistons with also Standard 4.00 bore into the engine.
Or what do you mean?
In Combination with the 62cc Indy heads it will be a 9.5 compression.
With the kb107 Pistons it will be 10.9 and In dont know if this is not to much for the engine. We have 102 octane Gas in Germany but In want a healthy powerful engine.

Best regards
André

Europe rates the octane differently than the USA. Your 102 is the top grade correct? I do believe it is equal to our 93 octane.

I have run a 360 @ .030 overbore with the KB-107’s set at a zero deck height before with a .038 thick head gasket and72 cc iron J heads.

Just pay attention to the distributor timing.

Now, since you said you wanted more power, just what is more power? Is there a HP number your looking for? An ET slip at the track to obtain?

A couple of more questions for you to help understand where you want to be. I hope you can answer these.

Cars weight, gear ratio, transmission (stock 904 or 727?)
Are you willing to change gear ratio’s and torque converter? Are the use of headers in the future?

Oh! 1 more thing….

Welcome aboard!

 

[Lemon_Belve]

That is the original stock camshaft.
This engine should perform like a stock engine of years past. Plenty of room for upgrades.
Yes it is possible. If the cylinder bores are not worn out. A light hone to address the cylinder surface will prep the cylinder walls for the new rings. Above, someone made a mention to the ridge that could be left behind from the current pistons and rings. If honing the cylinders do not take craw of the ridge safely for a stock sized 4.00 piston, then you’ll need to go to the next size available. This is normally a size of an extra .030 of an inch. BUT do so look to see if you can get the piston in a smaller oversize. .010 or .020.

Let you machinist decide the bore size before ordering pistons. Also, the amount a block can take in being bored is decided with a sonic check to see what the cylinders wall thickness is.



Europe rates the octane differently than the USA. Your 102 is the top grade correct? I do believe it is equal to our 93 octane.

I have run a 360 @ .030 overbore with the KB-107’s set at a zero deck height before with a .038 thick head gasket and72 cc iron J heads.

Just pay attention to the distributor timing.

Now, since you said you wanted more power, just what is more power? Is there a HP number your looking for? An ET slip at the track to obtain?

A couple of more questions for you to help understand where you want to be. I hope you can answer these.

Cars weight, gear ratio, transmission (stock 904 or 727?)
Are you willing to change gear ratio’s and torque converter? Are the use of headers in the future?

Oh! 1 more thing….

Welcome aboard!

Thank you for all your information.
Yeah after your post I think it will be better to bore and hone the Engine Block.
The KB Pistons are also in 0.020 available
The costs for boring are Not so a big Point
The 102 octane are our top grade, correct.

In case of power wishes, actual it have 275hp and I want to have healthy 400-450hp.
Only for our unlimited streets in Germany, no Tracks etc

For the Wight, its a original Belvedere II, only with the 360 Engine. I will buy it in 2 weeks
Its a original 727 Transmission with original rear diff and Gears
Which in Detail I will Check when the Car is in my Garage. Changing of diff Gear is no Problem.

In case of Headers, this Point will be my First one. I will Go with TTI step Headers

I see on YouTube a Guy with His 360 Duster. In his first 420hp step he use the Comp Cam XE275HL
Will this a good choice for Higher compression?

 

[496 polara]

Figure out where you want the power. Do you want a 1/4 mile beast with low gears or do you want a top end machine for your open roads? OR SOMETHING IN BETWEEN?

 

[Lemon_Belve]

Figure out where you want the power. Do you want a 1/4 mile beast with low gears or do you want a top end machine for your open roads? OR SOMETHING IN BETWEEN?

I think Something between with more focus on 1/4 mile
I think an old mopar is no Car to Drive longer Time over 130 mph
But when we Drive on our Autobahn I do not want a Stress drive when I drive 80 mph

I Like a powerful acceleration and I dont need a high Speed Monster

 

[rumblefish360]

The Comp cam is pretty good. It’ll work well with the higher compression your looking to use. I think your on track.
What did he use for cylinder heads?
What are you going to use for cylinder heads?