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Discussion Starter #1
I am working on a 1990 e30 325i with no motor. the body is in pretty good shape for a car with 340k on it but it only makes it easier to finish the new paint job since i didnt like the color. im going as far as i can with no budget (if i do get money is a few hundred bucks every couple weeks) so im trading my time instead. e30's are hard to come by around here so instead of rebuilding my m20 engine i decided to go for a simple swap to get some easy, reliable, cheap power. my question is will the big block cadillac engine i found fit the bay? i think its between a 455 and 472 but theres no way to tell until i seal the deal (for $300 its a steal, tranny and all). and for $400 for the car the total being $700 for a super light car with that much power, im not worried about moving the firewall back. the car is completely stripped down and im sanding the paint right now. the problem with the build is ive seen a lot of small block chevys in e30's and the engine looks massive. i dont care if it sticks out the hood a tiny bit but anyone got any big block swaps before? im determined to make it work with what i have. also would be good to know if the weight of the motors going to be the real pain? new suspension, sway bars, etc? thanks. im going into the build blind and its my first car resto. god help me....
 

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D'oh, You Kids!
1984 633CSi, 1985 635CSi, 1985 325e, 1987 325is, 1993 325is, 1995 318is, 1995 M3, 2003 F150
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WHICH big block Cadillac engine? If it's cast iron, you're wasting your time. It'll make the normally nimble E30 handle like crap.
 

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Discussion Starter #3
Im not too sure yet i havent been able to get my hand on the motor long enough for a close look. going to be able to do that later but its assumed between 472 and 500. sure, lets say it was cast iron, it might handle a bit more sluggish but if i move back the firewall and go for some stiffer struts wont that be good enough for the extra 200 pounds? its kinda set in stone that the 2 will mate, im just trying to make it so it isnt the biggest waste of time in the world. but ive never driven anything over 160hp so lets say its going to be a good starter for going fast. power to weight ratio should be great.
 

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I found the following weights listed:
BMW M20 engine: 258 pounds
Cadillac 500 cid engine: 625 pounds
YMMV

:drive:
 

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D'oh, You Kids!
1984 633CSi, 1985 635CSi, 1985 325e, 1987 325is, 1993 325is, 1995 318is, 1995 M3, 2003 F150
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Why did you title the thread "chevy big block swap" if you were planning on using a huge boat anchor like a Caddy mill?
 

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Discussion Starter #6
I've never used a forum before and I figured its probably similar to the weight of most gm engines that size unless the block was aluminum. But hey its 300 pounds too heavy, and then there's a tranny to go on it. The e30 transmission is pretty light, I can haul that around no problem. But the caddy and transmission combo could be pretty heavy all together, so let's just say the whole front suspension could be redone. Anyone got any suggestion for some coilovers that will handle that? And what should I do to the lower arms or just fabricate new ones?
 

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D'oh, You Kids!
1984 633CSi, 1985 635CSi, 1985 325e, 1987 325is, 1993 325is, 1995 318is, 1995 M3, 2003 F150
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I want you to think about something: the endearing quality of the E30 is its fantastic balance. By loading almost 400 more pounds on the front axle, that balance is gone. It's going to be nose-heavy no matter what you do with the suspension. It's going to plow in corners like a truck. And the cast iron Cadillac engines don't make a lot of horsepower for their size and weigh. Do what you want, but if you go ahead with this, I'm 90% sure you'll be disappointed, and you'll be butchering an E30.
 

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Why did you title the thread "chevy big block swap" if you were planning on using a huge boat anchor like a Caddy mill?
The Cadillac engine is heavy, but my research shows a Chevrolet 454 weighs about 590 pounds. So, the big block Chevy is lighter, but not by much. :(

:drive:
 

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..... And the cast iron Cadillac engines don't make a lot of horsepower for their size and weigh. Do what you want, but if you go ahead with this, I'm 90% sure you'll be disappointed, and you'll be butchering an E30.
The Cadillacs of those days were considered luxury cars, not performance cars. Acceleration was leisurely. Fuel economy on those engines was dire; about 10 mpg might be a reasonable estimate.

:drive:
 

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I'm going to go way off the wall here and suggest that you forget about a Detroit engine altogether.

Instead go for a Toyota Supra DOHC in-line six. It's been done before, to get a good price you'd probably have to go regular aspiration.

All that aside, putting a different motor in any car is a huge undertaking. My guess is it works about one time out of 10. The rest of the time the guy ends up struggling to sell it for parts to somebody.

Rebuilding an M20 might be the cheapest way to go.
 

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Discussion Starter #11
all good thanks everyone. you talked me out of the big engine im going back to my original plans. either an m20 2.8 turbo or s50 2.8 turbo. i was going to put the big engine in thinking it would be a great start for a large ci engine to upgrade. but the power to weight ratio would have been about the same with crappy handling... so im going to start a new threat on all the little things i need to do left on the body. its in pre-painting stages like sanding the paint and body filler but i expect to be done that in a month or so. theres a few hiccups along the way like this really tough coating on the lower half of the car about 6 inches all the way around, just gums up the sand paper and i want to re paint it... ill name the new thread "navoue's e30 turbo resto" and ill post the pictures and everything tomorrow. thanks again, i want something fun not bunk.
 

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D'oh, You Kids!
1984 633CSi, 1985 635CSi, 1985 325e, 1987 325is, 1993 325is, 1995 318is, 1995 M3, 2003 F150
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That coating is a stone guard. You'd be better off leaving it.
 

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Discussion Starter #13
no, im restoring the car. its going to come off, and be replaced. i need to check for rust. how do you remove it without some military grade paint stripper? its like rhino liner...
 

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D'oh, You Kids!
1984 633CSi, 1985 635CSi, 1985 325e, 1987 325is, 1993 325is, 1995 318is, 1995 M3, 2003 F150
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You use military grade stripper....
 

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Discussion Starter #15
I'm on like a $40 budget and the whole bottom of the car is coated in something "like" rhino liner. my guess is its some kind of rust protection. the only part of that I need to get off is some in the engine bay so I can afford that, then the rock guard you beamer experts would know something about should be removed so I can get any rust fixed up. Any ideas on how to remove it without shooting my ideas back at myself?
 

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D'oh, You Kids!
1984 633CSi, 1985 635CSi, 1985 325e, 1987 325is, 1993 325is, 1995 318is, 1995 M3, 2003 F150
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I was serious. It's going to take some really strong stripper to get it off. One that's available to the general public is "Dad's Paint Remover". Another is Strip-It Aircraft stripper, but even those will take multiple tries to get all the stone guard off.
 

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Discussion Starter #17
Thank you very much. Sorry, I didn't think I was right when I just suggest the heavy duty stripper. Thought there was an easier way. So both those are check, but the last little thing is the gas tank.. There's the door which looks rivited on, and the plastic ring that the gas cap sandwiches to the car. This come out easy? It's the last hole I'd like to clean up
 

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D'oh, You Kids!
1984 633CSi, 1985 635CSi, 1985 325e, 1987 325is, 1993 325is, 1995 318is, 1995 M3, 2003 F150
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The gas filler door bolts on from the inside. The surround at the filler neck comes out to the inside. I had the tank out anyway, so it was no big deal. I don't know if it can be removed with the tank and filler line still in place.
 

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Before I left the USA in 93 I did quite a lot of power builds with those Caddy motors.
They can make tons of Torque, so if you want to power up a Sherman tank...
There was a company in King of Prussia PA that specialised in parts for these motors and conversions.
Though the motors used to run about 50 to a 100 USD for a runner (they had excellent life expectancy) their go-fast parts were $$$. I know, since I sold them :)
I would NEVER put one into a light car. Even a NOVA with BBC performance front suspension would wallow with such a motor :(

But when I hear your budget, I'd rather forget about Turbo builds etc.
You'll be walking for a looong time due to breakages caused by underfunding.

Be realistic and plan the finances before declaring chapter 11
 
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