i've got my 4age sitting in the engine bay all bolted down in the engine bay. im waiting on a header and a throttle cable. but im having some trouble with a few vacuum lines. heres the deal. i have a Silvertop motor, but i got Dr. Tweak to wire my harness up for a blacktop. im running the car on my stock MAP sensor in the 6th gen. now i need to figure out what vacuum lines go where. can anyone help me out?

Dr. Tweak - God of celica swaps.

Here's a good link from club4ag with multiple pictures of the vacuum rail and so forth.

http://forums.club4ag.com/zerothread?id=25025

Also, you can cap off the both powersteering vacuum hardlines and one of the brake booster hardline (by throttle body #4) from the rail as they will not be needed for the swap.

This post has been edited by netrata: Aug 20, 2008 - 12:35 AM

thanks for the help man, i really needed that.

>

oooooh, I'm intrigued! This 4age swap is the one I will do some day.

Why a blacktop wiring harness for a silvertop? What's the advantage? Naturally I'm gonna ask Doc to do some work for me when the day finally does arrive... but do tell.

Purpose for the the the blacktop wiring conversion is to allow the engine to run open ITB's. Be warned though that the silvertop will be running rich due to the factory specs of the ecu was meant to be used on the blacktop.

so if i had a blacktop ecu and ran a MAP, with the blacktop wiring setup would i still run rich or am i good to go?

Yes you would still be running rich. You do need to consider that the blacktop has a higher compression ratio then the silvertop, I believe it was 11:1 as where the ST was 10:1. You can go to club4ag to to verify this since there are multiple threads based on the topic. Personally, I was also considering the map conversion over the AFM since I already have the silvertop in my car but since i've heard a few bad things about running blacktop electronics with the silvertop I decided to keep the AFM setup with my celica.

This post has been edited by netrata: Aug 23, 2008 - 8:02 AM

which ecu version are u running? ST or BT?

You can run blacktop electronics just fine. Although my silvertop was modified, I think it ran significantly better on the blacktop electronics than the stock silvertop's. Anyway, I hooked up the MAP as in the picture. As far as the rest of the lines go under the throttle bodies are mostly evap related lines, which you can plug more of. There isn't much in terms of vaccum lines because the 20V motors use electronic idle control, so as long as that and the main vac lines to the throttles are hooked up, it should run. If you experience any sort of lag or leak, spray some carb cleaner around the throttle area and listen for where the changes are coming from.


As far as running rich goes, my silvertop did not. There are varying opinions on how much more rich the silvertop runs on the blacktop ecu, but mine did not run rich at all. It ran perfectly normal.