[mustangboi]

Hey, i have an '86 gt thats stock. I was thinking about getting a top end kit and after reading a little bit, and recommendations from a few people i met i was thinking about getting the ford racing kit that comes with the gt40x head, cobra intake, 1.7 roller rockers and e303 cam. also thinking about 70mm throttle body, cold air intake and 24lb or 30lb injectors. the previous owner of my car had the exhaust system done. Its a 2'12 in. off road exhaust with h-pipe, 2 chamber flowmasters, and headers. Also a hi performance fueld pump and better coil have already been added. Think this would be a good kit to add on?

any suggestions are highly appreciated.:shiny:

 

[Joel5.0]

If you have the flattop pistons, typical in '86 SBF's, and don't want to upgrade them.... you're best alternative to ensure PtV clearance and performance, would be a set of TFS TW heads.

 

[bdbolling19]

the flat-top pistons in the '86 don't usually allow you to run large valves or high-lift cams without notching the pistons. you could just buy a piston notching tool, but, since the motor is an '86, a rebuild with a good set of pitons might be in order before you consider things like a new top-end kit.

that kit you mentioned should work pretty well though, but personally i would go for a trick flow or edelbrock top-end kit, unless of course you need the car to remain smog-legal.

 

[mustangboi]

no, my emissions are pretty much all together by-passed. cuz my smog pump siezed up about 2 years ago. wut about the 360hp trick flow kit. would that work?

 

[mustangboi]

i was originally looking at the Trick flow TFS-K514-360-350 top end kit. would that be a better buy? or would i have to get new pistons for that too?

 

[Joel5.0]

That kit should clear fine with the flattops, you should always check though.

 

[mustangboi]

ok, with that kit wut size fuel injectors and throttle body would you recommend?

 

[5.0Rookie]

Are you still running a speed density setup? If so, reprogramming would be required too if I'm not mistaken.

And rip that smog pump outta there. That thing weighs a ton

 

[mustangboi]

i already did, and wuts a speed desity set up?

 

[5.0Rookie]

If your '86 is stock like mine, it uses the speed density system. As I understand it, the computer has set parameters for dealing with air flow and fuel delivery. If your car has mass air, the computer has the ability to measure incoming air flow (among other things I think) thru a meter in your intake tube and adjust the amount of fuel to be delivered to suit. Mass air takes better to the big mods like what you're after. So, if your intake tube doesn't have a little box on it with wires coming out, you're speed density.

 

[EagleAutosports]

Physically, you can use the heads and intake in that kit but since that cam is included, you'll need to upgrade to mass air for that. The speed density system can't adapt enough to compensate for the change in pumping characteristics of the engine when changing the cam. Plus the cam, when used with stock 1986 pistons, wouldn't work unless they're notched.

 

[Joel5.0]

Speed density is the EEC system that does not use a MAF sensor, fuel trim function is based off the intake vacuum readings via a MAP sensor. Since the installation of an aftermarket cam will cause the vacuum readings (specially at idle) to be lower and pulsed (due to cam overlap)... speed density systems require to be upgraded to Mass Air.

The good characteristic of the relocated valves in the TFS Twisted Wedge heads design, is that they provide more room for PtV even if the flattop pistons are used with the kit's cam inclusive......

 

[Joel5.0]

Speed density is the EEC system that does not use a MAF sensor, fuel trim function is based off the intake vacuum readings via a MAP sensor. Since the installation of an aftermarket cam will cause the vacuum readings (specially at idle) to be lower and pulsed (due to cam overlap)... speed density systems require to be upgraded to Mass Air.

The good characteristic of the relocated valves in the TFS Twisted Wedge heads design, is that they provide more room for PtV even if the flattop pistons are used with the kit's cam inclusive......