ae86 - 7age build questions

[cdixon311]

Still working on the plan for this build. I'm actually not sure if I want to build an a series block yet. Seems like I may need to swap to a stronger motor to really get the power I need. I am definitely going to finish the 7age n/a project just so I can get the car on the road and start making it to events while I build the suspension and fix other stuff, but am still undecided if I'm going to do a 7agte or not. I've seen a few a series builds and they almost seem to fall short on power, and pushing an a series around 300hp will put a lot of stress on the engine which leads to reliability issues. I could easily get ~300hp and a ton of tq out of a Chevy small block and keep it somewhat reliable since it would be pretty close to stock. I will of course beat the sh17 out of the motor, but parts are cheap and complete engines are really cheap too. The increased weight bothers me the most, but I hate to fully build the 7a and not get the results I want.

Anyways, that's much further down the road. The 7age is going in the car for now, and will make it to events soon. I have the ae86 hatch, and a 7afe block (full engine from my ae92 7afte swap). I haven't sourced a head yet, and am wondering if it's really worth putting the extra time/effort/money into getting a 20v. I'm really leaning towards a big port 16v since they're easier to source and it looks easier to put on the car. Although, if I'm not going to turbo the motor and eventually replace it, it seems that a small port would be more beneficial.

Just curious what you guys think about that. Any feedback is appreciated.

and b/c everyone loves pics, here the donor engine (r.i.p. turbo):


and the project car:

[cdixon311]

I was also reading here http://www.whyturbothat.com/project86%20.html" onclick="window.open(this.href);return false; that the Honda a20 pistons will actually fit on these rods if I were to bore the motor out. It seems like there may be compression issues from using the 7afe pistons since they're dished. I hear that it drops compression below 9:1. They say that the small port pistons are better for this application. if I were to swap pistons, I might as well use forged, but if I'm not building the motor, why bother right? Or, I could bore out the engine a bit with the honda pistons to gain that extra displacement which could lead to some bigger gains if the cars pushing 14+ psi. Again, it almost seems like that's a lot of effort and money put into it, and I hear that increasing the displacement alone isn't really much of a gain. In the long run though, the extra displacement might be worth it when I turbo the engine, *if* I decide to fully build the 7agte.

Any thoughts on that? Compression ratios on our motors are still something I'm researching, so not 100% what ratio I want yet.

[cdixon311]

looks like a 7age 20v puts down around 144rhwp. Not sure what mods are on there, but I do see itb's

[GamblerZ]

I have that "Why Turbo That" website bookmarked. Interesting information on there.

[cdixon311]

yea, this was a good read too

http://www.whyturbothat.com/corollamain.html" onclick="window.open(this.href);return false;

[dr.occa]

If you don't want the extra weight but would like a more reliable motor then a tacoma 4 banger or another 4 banger Toyota pick up motor would be a good option.

For now thought I'd just drop in a 7A motor if you already have it and just get the car going while you plan out and collect the parts for your "proper" build.

[cdixon311]

Yea for now I'm going to do a 7age build and drop it in. The build is pretty easy, I'm just waiting on a few things to settle before I go buying parts. Keep an eye out for a big port head. They seem to be somewhat hard to find. It's almost looking like I'll have to buy a long block just to get all the parts I need...