Rockers? Cam? Springs? I am so lost...

[Woody6799]

I have done alot of reading which has only increased my confusion. Please excuse the ignorance but when it comes to engine internals I am as green as they come...

I just picked up a set of gt40's that are in pretty good shape. Before I slap them on my 94 5.0, I know I need to add springs and rockers. I have found links to the Alex Springs and the TFS springs... however I have found threads saying the Alex Kit is garbage and too soft and the TFS kit is not meant for the GT40 heads. The same thread stated there was some sort of TFS dual spring or beehive spring kit that needed to be machined in... Someone help me straighten this out so I can buy the right springs on my first shot...

Also, I need rockers. I heard factory crane's are fine but aluminum's are better. 1.6 is good, 1.7, is better but 1.7 may be too tall. Factory crane is quieter but aluminums can gain 5-10 more hp gain. So there is more confusion...

I am in no rush for this car, it is my project but I want to build it right. I chose the GT40's to maintain the original look and because I have read plenty of threads where they have proven more then capable. That is also why I picked up a 94 Cobra intake as well.

So here it is in a nutshell, those are my parts, I want to run NA 12's and have over 300hp. I am trying to plan it piece by piece but when it comes to the springs/rockers/cam I need some help figuring out what works...

 

[rz5.0]

The factory crane is fine. Ratio depend on cam and clearance.

 

[Woody6799]

what if I said TFS Stage 1?

 

[rz5.0]

I would still keep the crane if you have them.

 

[itsblue95]

im not to sure that setup will make 300whp unless you port the heads. i made 310whp and 316tq with AFR 185, holley systemax, and TFS1 cam, and all the other bolt ons. im sure it would have made more since my injectors started acting funny and was showing 100% duty cycle and they are 30lbers.

 

[rz5.0]

There some ppl that made 300 on gt40. You could of made more power with 165's.

 

[itsblue95]

There some ppl that made 300 on gt40. You could of made more power with 165's.

prolly could have but im looking at ahead since im gonna be doing a 347 this winter

 

[Raffaelli]

I have the trickflow springs on my gt40's. They work fine even if they dont fit absolutley perfect.

Dont forget to mill em 30-40 thousanths to get that compression up.

As for running 12's with those heads.... Hmmm. Kinda lofty.

 

[Woody6799]

there are plenty of guys on corral doing it... one guy is running 11.2 on ported gt40's and another is running faster without porting. it can be done and its what I am shooting for. I am not saying this set up alone is going to get me over 300 its just parts of the puzzle that will get me there.

 

[rz5.0]

prolly could have but im looking at ahead since im gonna be doing a 347 this winter

understandable thats smart

 

[fastbanshee1999]

woody,

Check out the motorsport b303 cam. I've have heard its a decent out-of-the-box cam. Pretty decent idle too As far as the springs, why dont you just put the factory ones on? I mean if its staying pretty much stock except the cam and intake, i see no reason to upgrade the springs.....

 

[rz5.0]

Stock springs are weak.

 

[fastbanshee1999]

Stock springs are weak.

So with the light mods he's wanting to do, you dont think they will hold up? How weak exactly are they? (im asking because i would like to upgrade mine in the future if i need to)

 

[rz5.0]

They come with single springs and cant really handle more than the stock cam.

 

[Musturd]

You can get in the 12's with those with a decent suspension setup nice cam and intake. I know I shouldn't have a problem seeing that I went 13.4 on street tires with bolt ons and gears. I'm using some gt40's on my new setup with a track heat intake and TFS 1 cam plus I got the sauce for added fun