Hey, I am trying to get some more power out of my new truck. This is what I have in it so far:

70 F100 4x4 with 89 351W, standard bore, headers (dont know which kind), aluminum stealth intake, 600 Elderbrock 4bb, Accel ignition, Comp 33-240-4 Cam, 351 head of 91. 3in lift, 33" tires, 3.73 rear end.

I looked up the cam and it was rated 2500-6500rpm and is considered street cam.

I am want this truck to throw you back in your seat when you get on it. Right now i cant even get it to break the tires.

Would I benefit from adding roller rockers and if so what ratio would be good with this cam. Also I was thinking about upgrading to MSD - Ignition, Distributor and Coil.

Any thoughts? I appreciate any advice you might have.

Thanks

Craig

 

33" tires, and 3.73 gears....... think that might have more to do with it then anything..... 2500-6500RPM cam = High Stall Torque converter...... not what I would have picked but if done right will work ok..... but getting to 4.10 or 4.11 gears will do so much more for you........

 

I just bought the truck two weeks ago and that was the cam it had in it. Wouldn't have been my choice either. That is why I am debating weather it is worth it to keep it or exchange it. Hopefully I can get some good opinions on what to do.

I was thinking the same about changing the gears.

Thanks for the reply

 

How would the truck do with the lower gears and C6 3 speed auto trans? Would I loose all my top end speed? Mainly want to keep up with traffic on the highway.

 

I would recommend an RV cam, dual plane intake and some lower gears. You would be wasting money on roller rockers or an MSD ignition. Small primary tube headers will also help.

That truck is heavy, you're turning some big tires and it's not going to be easy to get that "thrown back in the seat feeling" unless you swap in something big with a lot of torque ala: 460

 

Thanks Area351

 

The Comp 33-240-4 is a big block FE cam which won't work in a Windsor so you were either misinformed about the cam or you don't have a Windsor under that hood. If it is a Windsor then maybe the cam is similar and based on your description of how it performs this wouldn't be an unreasonable assumption.

Anyway.. regardless what motor you have that cam has got to go... it's all wrong for a truck motor. 244 degrees duration at fifty thou!! Putting that into perspective.. it wouldn't be totally out of line to use a cam with a total advertised duration of 244 degrees. And yes those E7TE heads are too small for this motor but that cam is all wrong for a truck even if you had AFR185's on it. My suggestions are to swap in the Comp 35-234-3 and look for another set of heads, GT40s would be a good upgrade but there are lots of lightly used aftermarket heads out there too. With this displacement the motor is airflow limited above 5000rpm with anything smaller than those AFR heads mentioned above so there is no point using a cam that pushes the powerband higher, but you could still get 300-350hp and lots of tire smoking torque at these rpm levels.

 

Thanks for all of the information. So I went and looked at the block numbers : E9AE-6015-AA-13. When I looked it up, it says this is a 351C. Is that good or bad?

 

Ford casting numbers won't tell you what series of engine you got but just going by the date(E9 = '89) eliminates everything but the Windsor family since all the others had long since been discontinued by that point.

 

Awesome, as usual your a wealth of knowledge. So I need to find some gt40 and get a new cam. If you have any suggestion for other changes I am all ears. Again thanks for your help

 

Would I be able to use these heads? Craigslist: gt40 heands and intake gt40 heands and intake

 

Gt40 heads will need to be drilled for 1/2" head bolts to run on a 5.8L engine.

They are setup for 7/16" bolts and meant to run on 5.0L engines.

Btw: Unless you are swapping to EFI, that intake listed on the craigslist post will do you no good. It is worth about $100 though.

 

Area351, that is good information to know. Would my intake work with the gt40 heads? I have stealth weiand intake.

 

Yes, your intake will work.

Just take the heads to a machine shop (or do it yourself on a drill press or mill) and open the bolt holes up to .531" diameter. That'll give you clearance for a 1/2" bolt.

Lots of people have swapped the Gt40 heads on to 5.8L engines. They are cheap and good for about 25hp stock and around 40hp with some mild port work. AFR or Trick Flow heads will flow MUCH better than Gt40's and can be found used pretty cheap.

I personally would change the cam first and regear before spending time and money on a head swap. Those two will net you better acceleration for the money spent.

Change the cam first and take it from there. You might be pleasantly surprised. Borrow a set of smaller tires and see how it reacts then. It'll be similar to a gear swap as far as acceleration goes.

 

Thanks, I have to call around to some junk yards tomorrow to see if I cna find some axle's to swap.