Performance rebuild on m30 (3.0cs)

posix

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I’ve read lots of people swap out the engine for like a 3.5L to gain more HP.

what are the suggestions if I want to keep the original 3.0cs m30but rebuild to get more hp?

What are the cons of doing this vs swapping?
 
Higher compression pistons, bigger cam, headers, triple Weber sidedrafts are some upgrades for the original engine, not sure if Megasquirt works on original block, @sfdon knows all the tweaks to consider
 
sfdon is all you need to know for performance engines for a coupe. there are other excellent choices, but Don is across the bay from you on Alameda. give him a call or send him a PM on the forum. @Stevehose has the right answers up there, but Don can tell you anything about megasquirt possibilities. higher compression pistons can be found, Don probably knows where to look.
 
There is no substitute for cubic inches. If it was me, I'd park the original long block on an engine stand and start with a 3.5l long block. It costs the same to modify the larger motor, and you are starting with a better head.
 
There is no substitute for cubic inches. If it was me, I'd park the original long block on an engine stand and start with a 3.5l long block. It costs the same to modify the larger motor, and you are starting with a better head.
If I want to keep it carbureted, I just need the block and the head right? Everything comes from the current engine?
 
Suggestions...

as noted by Senor Bavarious- early heads are only valuable as a boat anchor unless you have a Csl In which case it’s a rare injected head that you need.

If you are stuck on an original 3.0 engine- that’s great but at least upgrade to higher compression pistons and a later head with the improved coolant passages.
I‘m across the bay in Alameda - almost 20 coupes and engines to look at.
it’s a rare situation where a 3.5 engine isn’t the best choice.....
4BF55AD5-9432-4DAB-831B-655AB581DC6F.jpeg
 
Suggestions...

as noted by Senor Bavarious- early heads are only valuable as a boat anchor unless you have a Csl In which case it’s a rare injected head that you need.

If you are stuck on an original 3.0 engine- that’s great but at least upgrade to higher compression pistons and a later head with the improved coolant passages.
I‘m across the bay in Alameda - almost 20 coupes and engines to look at.
it’s a rare situation where a 3.5 engine isn’t the best choice.....View attachment 97281
I’m in Palo Alto, if you have time and are willing, would love to go by sometime :)
 
I’m here until Thursday? - after that I’m at CK and La Jolla tuning cars,
Back early next week.
you have a pm with ph. Number
 
If I want to keep it carbureted, I just need the block and the head right? Everything comes from the current engine?
The long block includes everything but the intake and exhaust. You can use your carbs, oil pump and pan, accessories, water pump, thermostat housing, valve cover, upper timing cover, etc. You will need a cam adapter nut to drive the distributor and a pilot bearing for your tranny. You may need to adapt the motor mounts depending on the year of the block. Easily done.
 
Easily, but not inexpensively.

Speed costs money, how fast do you want to go? (I've read here).

Fast, good, cheap. choose two.

But, having a BMW K1300GT with 4.5x the power of my first Bug, and weighing on 40% of the Bug, power is addicting. OTOH, look where it got your various dictators.
 
The long block includes everything but the intake and exhaust. You can use your carbs, oil pump and pan, accessories, water pump, thermostat housing, valve cover, upper timing cover, etc. You will need a cam adapter nut to drive the distributor and a pilot bearing for your tranny. You may need to adapt the motor mounts depending on the year of the block. Easily done.
Hi Mike

I am thinking of building a 3.5l M30 for my '73 bavaria. I would stick with carbs; not sure about number or draft yet; I like the sound and simplicity of carbs. I would purchase a long block, tear down etc, maybe hop up the hp a wee bit with mild cam and pistons...maybe... and transfer your list above from my 3.0 to the 3.5. However, I do not know what a 'cam adapter nut' is; please explain?

THX
Bill
 
Hi Mike

I am thinking of building a 3.5l M30 for my '73 bavaria. I would stick with carbs; not sure about number or draft yet; I like the sound and simplicity of carbs. I would purchase a long block, tear down etc, maybe hop up the hp a wee bit with mild cam and pistons...maybe... and transfer your list above from my 3.0 to the 3.5. However, I do not know what a 'cam adapter nut' is; please explain?

THX
Bill
camshaft adapter nut 11311284801 - it allows you to run your original distributor drive with a newer cam such as the one in a B35.
#18 in the drawing...

 
camshaft adapter nut 11311284801 - it allows you to run your original distributor drive with a newer cam such as the one in a B35.
#18 in the drawing...


THX mike,
What does the cam adapter nut replace on a M30B35 long block?

Cheers
 
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