Ranger v8 swap and explorer questions

[pettyeod]

have; 94 ranger with 4cyl. A 66' 289 with great rotating assembly with flat top with double valve relief pistons, gt40p assembled heads that came right off an explorer, Cam and Lifters, Hydraulic Flat Tappet, Advertised Duration 280/289, Lift .449/.473, the stock explorer exhaust manifolds, and will get the next couple things for conversion components. Motor is halfway done and 4cyl is still in the ranger.
Questions: 1 is explorer motor a roller lifters motor and I have to convert 289 or can I just use my hydraulic lifters and the gt40p stock rockers? BTW, the explorer pushrods look to work perfectly in 289 with explorer heads on it.
2 is what I have ok with a 100 hp shot of wet nitrous "on occasion"? My pistons are cast seal power decent set (not forged), stock hipo I beam rods.

 

[Josh B]

Awesome man, welcome to TRS

 

[rubydist]

Yes, the Explorer 5.0 is a roller cam engine. No, you do not have to convert your 289 to roller cam, you can use the flat tappet cam if you desire. The heads don't care about those things. You didn't tell us the lobe separation angle on the cam, so we don't have enough information to tell you if that is or is not a good choice of cam. You can use the factory rockers on the GT40P heads, but nearly anything aftermarket will be better.

I would not use nitrous on cast pistons, but I'm fairly conservative in that area - I want the engine to last.

 

[19Walt93]

I alos wouldn't put nitrous on an engine with cast pistons. Your cam sound like one Summit sells, if so, it has 204/214 duration at .050(advertised duration is almost meaningless) on a 112 lobe separation and should make decent power from about 1500-4500 or so. The P heads should also work good in that range, they were designed for torque- not high end power. P heads need unique headers/manifolds and choices are limited. In recent years there have been a lot of flat tappet cam failures, often blamed on lifters. If you can handle the cost of a roller cam, a set of drop in roller lifters, and new pushrods it might save headaches in the future. A roller cam can have steeper ramps so it'll make a little more power and it would also have less parasitic drag.

 

[dvdswan]

Welcome to the site.

If you want the truck to connect to the ground, you'll need some suspension work as well.

 

[pettyeod]

Thanks for the help!
I kept the explorer exhaust manifolds and they cleaned up well, will do ok for now.
I have a plan for the rear-end of the truck, more rubber and tighter suspension for starters.
As for the roller, I already got a new cam and lifters and timing chain/gear set. As for nitrous, I'll get it running and driving as is for now and make sure the truck is prepared for it first. It will be a c4 transmission. It's just a project so I don't mind pulling motor down the road if it's held together and upgrading.. should be fun!

 

[19Walt93]

One of my former techs had a pretty stout 302 in his 12 second 70 Mustang. After his experiment with nitrous blew pieces of the #8 piston into all the other cylinders, he pulled the nitrous and built up the 460 from the F250 he towed with. Be careful and do not use a vacuum secondary carb with nitrous. Explosions can be fun buth they're expensive.

 

[Josh B]

I think a C6 would make a good one with that ultra low 1st gear, then 2nd might take it on through the quarter

 

[pettyeod]

One more question. Pushrod length. With the 289 with gt40p heads the pushrods will be longer since I went from a roller motor to hydraulic flat tappet. Summit recommended COMP Cams 7831-16 High Energy 6.881" Long, 5/16" Diameter Pushrod Set
I put them in and no wiggle when no load but seems like at full push it doesn't seem to really push the valves very far. I ordered a pushrod checker and will get into it. Q. How much movement do the valves really see? 1/4 inch max?

 

[pettyeod]

Also,
Gt40 heads on 289, 450cfm, 550, 600cfm 4 barrel?

 

[rubydist]

The cam you listed above has lift of .449 / .473" and the cam card should tell you but most likely with 1.6 rockers, so your valves should be opening close to 1/2"