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Discussion Starter #1
yep it's official the little rx7 is going to be powered by chevrolet :thumbup: i sold the engine out of it this past sunday so i'm going to get started on it here soon then p/u on it again when i get back from vacation next month.

i'm going to start the journal on here in the next couple days but i just wanted post it on the board to tell EVERYBODY 1st b/c i'm pretty stoked about it. i'm also going to make a write up about it in the rx7 forum where i hang out at so others can see my beatiful work of art :D and to show em what a real engine looks like :evil:

-J
 

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jesse,

Here's the RX-7 I did some years ago with a 307 Olds/350 trans in it. I purposely tried to keep it as stock looking as possible on the outside. About the only clue you can see in picture 2 is the modified radiator/radiator position which had to stick out a little below the front air dam.

This is not too difficult as far as conversions go but I do have one word of advice. I think you'll want to make some front suspension modifications in order to retain the RX-7 ride and cornering. I didn't and I always felt the car was very front end heavy after the swap - just never handled quite the way it did before. I'm not sure what the answer is (higher rated springs possibly) but you'll want to compensate somehow for the additional weight of the engine.

Should be a fun ride when you are done.



 

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Grillin Randy
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My brother has an RX7 that he has been planning on putting a small block in.
He bought sbc mounts for it from some company in Canada, I cannot remember the name of the company. He has not worked on it in quite a while.
But now he wishes he would have bought the small block Ford mounts.

I hope you make faster progress on yours than my brothers.
 

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Lost in the 60's
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Dang Jessie! Your stoked aboput two things now at the same time...wow! I guess you are feeling so good that you don't need anymore brownies. Hear that Mikey??? No more brownies for Jessie, Lmao :D
 

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Discussion Starter #5
cboy, thats awesome to see a 1st gen. w/a V8 swap. nice job :thumbup: anymore all i see is a few FC's and tons of FD's with the V8 swaps. i guess more FD's than FC's b/c if you can afford the FD than you can afford the swap too.

you said "years ago" you did this...right? where did you get the engine cradle and mounts? i know Grannys speedshop has it now but i don't know how long they been around. as for the weight thing, i read on grannys website that the chevy V8 is only somewhere around 100-150lbs heavier (depending on the "stock" parts used). i'm going to try to keep it as light as i can in the front to stay as close to the 50/50 weight distrubition that the car originally cam equipped with. theres alot of tricks out there for that such as using alum heads, lightened flywhell, relocating the battery to the rear etc. etc... but you are still right, no matter what you put in there if it's not another rotary it's going to be heavier so i'll still have to "beef-up" the front suspension a little. or maybe i otta beef it up alot so my engine don't smack the ground when my car comes back down from doing a wheelie all the way down the road :confused: :D

crash, i only have 2 things to say about your brother.
1: he must have a 2nd gen. thats how all FC owners are haha j/k i couldn't resist.
2: does have the engine cradle? if so you should see if he wants to get rid of it.

ya H-man my winter (feels more like fall down here) is starting off pretty good and it's about time something good happend. i'm way over do for some good, i just hope it sticks around for a while ;)

-J
 

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Lost in the 60's
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Where is Titusville Jessie? You said down here....does that mean south???
 

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Lost in the 60's
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OK...I'm in north east Mississippi........Tupelo......the birthplace of Elvis. It gets very humid here in the land of cotton. :)
 

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jesse01 said:
... where did you get the engine cradle and mounts?
That's one reason I mentioned this is a pretty easy swap. I made my own mounts. In fact, they are more or less "spacers" rather than mounts. Turns out the mounts on the motor sit right over the mounting pads in the chassis and locates the engine in an ideal position so that the pan etc. do not interfere with anything. I simply used a 2x4 piece of rectangular tubing as a spacer on top of the mounting pads on each side, drilled them in the appropriate spots so everything could be bolted together. The spacer is necessary to get the carb set in a horizontal position.

As I recall (I built this back in the early 90's so my memory has faded a bit) the trans mounted right to the RX-7 cross member by using the mounting plate from the car I took the trans out of (a Buick Regal) and drilling it so it could be bolted to the Mazda cross member. I don't think I even had to do any welding.

The trans IS a tight fit but I didn't have to cut any of the tunnel to get it in. I just had to beat on it in a few spots with the Big Hammer.

As noted in the picture the radiator was a bit of a problem. I used the radiator out of the Buick Regal and had to tilt it back pretty far at the top to get it to fit...and it still stuck out the bottom by a few inches. But it did clear the hood.

If you want to use the stock hood and not chop a hole in it, you'll have a bit of a challenge to get an air cleaner to fit. I had to section one down to just a bit over 1" tall so I could get the hood closed. The better option, of course, is to just put a big 6-71 on that sucker and let it stick right up through the hood.
 

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Discussion Starter #10
oh ya homemade? thats a true rodder :thumbup: i'm gonna cheat (tee hee) i'm just gonna order the engine cradle and trans mount from grannys most likely and probably everything else too since they carry EVERYTHING you need for such a swap. or i'll just ask some of the guys in torquecentral.com since most of them are V8 rx7 owners, i'm sure some of them have some left over parts :D

the only thing i'm really worried about is smacking the oil pan on the ground, i'm not really all that worried about the hood issue (but then again i'm nowhere close to that point yet either). i plan on going w/a holley mpfi system so it should sit lower than the carb set-up but i dunno yet i'll find out when i get there i suppose.

btw, when you finished yours how fast was it? did you take it to the track?how'd it feel....besides being heavy in the front end.

-J
 

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jesse01 said:
...btw, when you finished yours how fast was it? did you take it to the track?how'd it feel....besides being heavy in the front end.
Interestingly, I made this swap as a practical matter...not to build a killer street machine. The rotary block in the Mazda had warped and was toast. At the same time my daughter went off to college leaving behind her rusted out Buick Regal/307 Olds. So I took two problem cars and combined them to make one nice running, interesting vehicle...which just happened to be able to burn down the tires. I drove the car pretty easy, however, because it still had the Mazda rear end and I didn't want to face converting over to something healthier. Never had it to the track...but then a stock 307 isn't going to provide very impressive numbers no matter how light the car is.
 
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