help me figure out how to 4ag a corolla

[ranterc]

i have an 87 corolla with a 4ac engine  , which is a single cam 8 valve 74hp eninge .. its not bad as a daily driver it keeps up with the flow of traffic alot better than my previous car which was a 3e powered tercel also sohc but with 12 valves . . the 4ac feels pretty torquey for such low #'s ..the diffenece i think is that the 4ac is a 1.6 vs 1.5 and all 86lbs of torque hit at 2800 rpms comparred to the tercel which waits till almost 4000 rpms to see all of its 87.lbs of torque ...

ok side tracked a little .. the 4ac block is identical to the 4age except the 4age is giving stonger internals,many 4ac faithfuls swap blocks but keep the sohc head , supposed ot be a straight up bolt on affair with no mods ...

however i think that if i were to go that far i might as well do the whole shabang and do the dohc ... but of course that adds more complications cuz of the efi deal ..

 correct me if i'm wrong .. but in older carbed cars like mine .. isnt the sole funtion of the ecu only to control emmissions related parts?
if that is so , paradise racing sells an intake manifold for side drafts for the 4age , matcht that to some webers and as far as fueling i should be good ... proly need a fpr and a better filter but thats small stuff i guess..

then theres ignition.. thats where i get a little lost .. if i use the dist. that comes with a 4age any reason that shouldnt work ? i mean since there will be no ecu ? would some sort of msd system save me ?

yes i know , in a world where almost everything is computer controlled why do i want carbs , dont get me wrong i love tha sound of a bov just as much as any other car enthusiast .. but i've always been a fan a all motor power ... love the sound of side draft carbs

 

this is all , as you can see still in the planning stages , various ideas rolling around my head , was thinking maybe even 7age , but that would add complications .. or i may just keep the sohc 4ac and see how far that takes me

anyways any advice would be great

[laz]

No experience on this, but one thing comes up to mind. Would you not loose the flexibility of tuning the engine optimally if you went with carbs over injectors? I thought that was the main advantage of injectors, the precise delivery of fuel when needed?

GL

X

[ranterc]

well yes and no i think..

a carb can be tuned using differnet jets and whatever , but it is said to be alot more finecky ....  especially when being tuned for high performance ..  your car will run great today .. and then run like **** tommorrow cuz the humidity is a tad too high.. you would need to constatnyl tune it for optiumum performance .. or so i've been told , i personally dont have much experience with carbs...

although the same kinda holds tru for efi , no? maybe not as bad tho..
i mean an efi car taken to a dyno and tuned in lets say Boston , wont run quite the same in arizona ?

[laz]

Yes, car at different altitudes and barometic pressures will act different.

This is from back in the days, but when we use to take a trip on a carburated car going from low altitude to high altitude they use to have to tune the car (carburetor) so that it would run optimally at high altitude. So it ran like crap until it got to high altitude.

With modern eletronic controls this is all done on the fly by the ECU, and even though you may loose some HP on the high altitude, the car will still run optimally at any altitude.

This is why forced induction rocks, and why turbo/SC cars do great at whatever altitude.

I really think you should stay away from carburetors because it will limit your performance options.

GL

X

[Darkest Edge]

Turbo and superchargers will loose some power also.  Any drag event and auto racing held in high altitudes, the cars have to be retuned.