Has anyone tried installing 1.7 ratio roller rockers on a speed density fuel injection system? I talked to a tech. guy from Crane Cams about their camshafts and roller rockers and I was informed that my 2021 camshaft is the most aggressive flat tappet cam I can get away with for a speed density setup. So to get more lift, I was thinking about converting to 1.7 ratio rocker arms. I asked the technician if he thought there would be any potential problems and he said he wasn't sure. So I was just wondering if anyone had tried this and if they noticed any poor driveability side effects from this. Thanks!

 

TF, I think I am just going to let you do all these mods to your truck first, cause you seem to be doing almost exactly what i want to do.

 

TF,
There may be a possiblilty since you are maxing out the system with the cam that you are going to use. The system is only set for a certain amount of air that will enter the engine. If you max it out with a cam, then go even more-Well, the computer may not like it. I have been wrong in the past (did I just say that outloud?) , but this is what I think will happen. Maybe someone has done this and will prove me wrong.

 

If I am not mistaken (and I usually am wrong) a custom burned chip will solve any problem you have. So far I have no chip and I have gotten away with porting heads, crane cam, headers, FIPK, true duals, 9.5:1 badger pistons and a slew of other performance upgrades when going thru my engine and I have yet to have a problem, (still have stock upper and lower intake though) or trip a sensor other than a bad 02 sensor. I was planning on a chip one day after all the mods, so I could have one custom burned once instead of everytime I mod something, but am beginning to wonder if I will need it with all I've already done

 

ccsnseven,

What setup do you have? (ie engine, s/d or m/a?) Also, which cam do you have? I talked to Mike Troyer yesterday and I asked him if a custom chip would help with a beefy cam and higher flowing heads and he said that there was only so much a chip can do for a speed density system. Probably what I'll end up doing is swapping the heads and converting to 1.7 roller rockers, and if I have problems, I'll just do a mass air conversion. I might have to switch back to speed density though when I go in for smog checks.

 

Not sure with speed density, but with my mass air setup I have the mods listed below with no issues. I also run a 92 Mustang with a 351 and Turbo setup on the stock computer and electronics

oh and by the way I happen to have a set of 1.72 rockers for sale

 

what kind and how much???

 

Crane, 100 bones plus s/h

 

I want em I want em....Did you forget about me lol

 

email me at Kujo007@hotmail.com and we can go through the details

 

FORCEFD,

How do you like your JBA headers? I need some new ones and I was thinking of going with JBA. Any comments, good or bad?

 

no complaints. Bought mine used so I only paid half price. New these things costed like 400+. They started to rust after 2+ years just like all headers...even though they are coated

 

TF:

Sorry I didn't post sooner, outta town, I have speed density and have been contemplating whether or not to convert, I also have the 2021 cam.
Like you I am also considering swapping heads, thinking about the gt-40 heads, (not the "P" heads, already have headers) upper and lower intake, but thats a ways off for me. If I have any trouble I figured I could always go back and convert to mass air.
Sounds like we are thinking a little bit alike

 

is there any issues with the increased lift causes piston valve problems? i would think that since you already have a better cam the extra lift isnt going to do much, however the reduction in friction could be a 3 to hp gain. maybe aset of roller 1.6.