Building a 7ac
Posted: Fri May 28, 2010 10:41 pm
I know that most of you guys are disinterested in this build because you have 16v and 20vs but I though I would post up for anyone wanting to build an interesting single cam set up. Ive been working on my 7ac for about a month now its nothing beastly but its a work in progress. I thouhght I would make a build thread for it as well as share all of the information Ive learned so far.
So the story begins with my AE86 I bought it about a year ago It was an automatic SR5 kouki coupe. I did the manual swap drove it for a few months and then my little 4ac dropped a valve . So thecar ended up sitting around untill I got some money to put her back together. Everyone and I do mean everyone told me to do a 4ag swap which cost to much, its fuel injected,making it harder to work on, and you have to buy a hard to find gts bell housing, plus I had just bought a new clutch flywheel and starter for my 4ac.I was talking to HVGuy who happend to have a 7afe and he was tellng me that he was thinking about building a 7ac it sounded like a good idea to me so I got 7a from him.
I took the 7a block to the shop and had it bored .50 over I had wanted to get forged pisotons for it but there were none what were affordable in the least bit so I had to go with cast. I thought about going with forged 4ag pistons or agze pistons but I did not want to complicate things futher. After boring it .50 over I had the shop blance the rods and put the rotating assembly together reseat the valves install double valve springs and I put my schnider racing cam in.
I put it all together I used a 4ac headgasket and a timing belt from an 85 doge colt cut the water outlet tube
because the 7a block is taller and put coolent hose over it I had to use the 7a lower timing belt sprocket set the timing marks and then put the 4ac one on I used the harmonic balancer from my 4ac because I wanted to run ac lol I also used an oil pump and belt tensoner from the 7a and I had to grind down the water pump to get the timing belt to clear. I put it in the car fired it up and everything ran pretty good.
Before I got it on the road the new thermostat failed to open so it overheated and blew the head gasket so I replaced it with the head gasket form the 7a which brought the compression up from 180 to 200. when I finally got to drive the car on the road its really good in first and second it still is far from a third gear motor which is what I wanted to see I have a really lowend cam in the car though it pulls like a single cam 240 in first and second but I plan on going turbo in the next few months im going to try and run 5-7 pounds of boost and see how it goes.
Here are some pics of the build I hope you guys enjoy it . If anyone is interested in doing this feel free to ask me questions about it
So the story begins with my AE86 I bought it about a year ago It was an automatic SR5 kouki coupe. I did the manual swap drove it for a few months and then my little 4ac dropped a valve . So thecar ended up sitting around untill I got some money to put her back together. Everyone and I do mean everyone told me to do a 4ag swap which cost to much, its fuel injected,making it harder to work on, and you have to buy a hard to find gts bell housing, plus I had just bought a new clutch flywheel and starter for my 4ac.I was talking to HVGuy who happend to have a 7afe and he was tellng me that he was thinking about building a 7ac it sounded like a good idea to me so I got 7a from him.
I took the 7a block to the shop and had it bored .50 over I had wanted to get forged pisotons for it but there were none what were affordable in the least bit so I had to go with cast. I thought about going with forged 4ag pistons or agze pistons but I did not want to complicate things futher. After boring it .50 over I had the shop blance the rods and put the rotating assembly together reseat the valves install double valve springs and I put my schnider racing cam in.
I put it all together I used a 4ac headgasket and a timing belt from an 85 doge colt cut the water outlet tube
because the 7a block is taller and put coolent hose over it I had to use the 7a lower timing belt sprocket set the timing marks and then put the 4ac one on I used the harmonic balancer from my 4ac because I wanted to run ac lol I also used an oil pump and belt tensoner from the 7a and I had to grind down the water pump to get the timing belt to clear. I put it in the car fired it up and everything ran pretty good.
Before I got it on the road the new thermostat failed to open so it overheated and blew the head gasket so I replaced it with the head gasket form the 7a which brought the compression up from 180 to 200. when I finally got to drive the car on the road its really good in first and second it still is far from a third gear motor which is what I wanted to see I have a really lowend cam in the car though it pulls like a single cam 240 in first and second but I plan on going turbo in the next few months im going to try and run 5-7 pounds of boost and see how it goes.
Here are some pics of the build I hope you guys enjoy it . If anyone is interested in doing this feel free to ask me questions about it