Considering a Roush 342R - Anybody using em or have an openion

[Treintjes]

A local Ford dealership is selling a Roush 342R turnkey for about $7K. It's not exactly what I've been looking for but am considering it due to the price. Initially I was looking at 347's but kept on hearing about oil consumption and excessive side load pressure on the pistons, since then I started looking at 351's with about 400hp instead. I have not goofed around with a car in the last 20 years but am thinking a 351w with 400hp will provide good street manners, very driveable, reliable, and maybe economical to operate if I drive conservativly. I am afraid I may be thowing all those things out the window by going with this motor. 450hp out of a 302 block seems like a lot to me.

Any insights, thoughts, or experiences are appreicated.

Thanks gang,
-Travis

[gtaroger]

I've been going in Roush's shops for years. They put together some really great motors. That said, Ford sales a 351 crate motor thats 385 HP that would make a great motor for your cobra. They also a stroker motor based on the 351W motor thats 430HP. I think one of these's two would be a better choice. Just my 2cents worth. Roger

[Luthersnake]

I have a 351 w/400hp from Engine factory..runs great. If you are looking for about 400hp I would suggest going with more cubes as it will be easier to get that from a larger motor....as Roger said, just my $.02...good luck!
gerry

[4U2NV]

I have a FPS 347 and love it

If mine wasn't bored .030" it would be a 342. As far as I know there will be as much side wall pressure on a 342 or 347. The only difference is the bore. I could be wrong. If so oh well

[1stgen]

Only difference is the 0.30" over bore. The oil consumption issues are long gone as new piston were made that moved the rod pin out of the oil ring land on the piston. As far as side thrust issues (ie rod ratios), they seem to be non issues currently. People on this forum regularly make 500+ HP with stock 302 blocks with no issues. The stock blocks can handle even more in street driven cars. Some guys run a 4.00"-4.10" stroke in stock 351w blocks to get 408-420 CI with no problems as well. The 342/347 is a well documented winning combination, whether it is a Roush or Ford. Hope this helps.

[Treintjes]

What do you guys think about the streetability and gas mileage associated with a 450hp 342? Ya I know it's a race car and gas milage should not be an issue but I want to use it all the time. This is my first Cobra and I'm excited.
-Travis

[KevinM]

If gas mileage is a big issue, use a Mass-Flo system instead of a carb.

Kevin

[ghalleck]

I have one of the early Roush 347R engines serial number 02-005 (5th one they built and the first one sold). Serial number 02-004 was in their test car, a Maverick that I believe they said ran the 1/4 in the 11's. I too was concerned about the streetability of this combination. But I've driven it two summers without any problems. It has over 400 lb-ft of torque at around 2900 rpm to about 6000 rpm so it is quick. But you can drive it easily in traffic. This fall I drove in a small parade with a couple of fair princesses sitting on the back with no problems. It idles fairly rough due to the cam Roush has installed, which I like. I have a 770 cfm Holley carb, but someday I would like one of the nice injection units.I get about 12 mpg around town and 16 mpg on the highway. At shows, the Roush name on the covers gets a lot of attention. If that engine is complete it is much less than the current price.

[Steve]

Originally posted by Growler:
Only difference is the 0.30" over bore. The oil consumption issues are long gone as new piston were made that moved the rod pin out of the oil ring land on the piston. As far as side thrust issues (ie rod ratios), they seem to be non issues currently. People on this forum regularly make 500+ HP with stock 302 blocks with no issues. The stock blocks can handle even more in street driven cars. Some guys run a 4.00"-4.10" stroke in stock 351w blocks to get 408-420 CI with no problems as well. The 342/347 is a well documented winning combination, whether it is a Roush or Ford. Hope this helps.

Pistons with the rings moved out of the connecting rod hole have a rather compressed stack of rings. There have been owners of motors with these pistons that have had sealing issues so they are not problem proof. The other way it's handled is to have the lower ring land positively locate the lower oil ring using a pin in the land. This keeps the lower oil ring from ever rotating and prevents the gap in the ring from ever getting over the gap in the ring land at the rod pin hole. I agree it's apparently a non-issue for almost any of the current stroker packages on the market today.

As for making 500hp with a stock 302 block, that's a combo living on borrowed time. How long is anyone's guess, but from what I understand, it's fairly common knowledge they eventually split in half at this level. The mains and webbing in the block are not sufficiently thick enough.

I think Roush motors are top dollar units. They use the World Products blocks, which are very heavy duty pieces. This is a block that could easily support 500hp.

I firmly believe you can build just as powerful a combo for far less money using a stock block, better heads, and similar aftermarket components.

A 351W block is what Travis has in mind. Personaly I would use recon stock rods with ARP bolts and put a 393 cast steel crank in it with some Hyper pistons. Bolt some decent aluminum heads on the block, a Performer RPM intake, the Holley Street Avenger 770, and a properly matched cam, and have a boatload of fun, streetable torque for far less money than the Roush piece.

If you really like the Roush look, Jegs sells the Roush valve covers and a Cobra Oval style air cleaner too. I'd probably want Roush heads if I had Roush valve covers, but that's your choice.

[1stgen]

I found it hard to believe myself but I witness year after year, 5.0 drag cars at New England Dragway run unbelievable stuff. These are not "R" blocks or "sportsman" blocks either. Large hits of nitrous and 12-15 PSI blowers (with o-ringed head gaskets of course). These guys are running multiple seasons before a rebuild/replacement of the short block. Put that into a lightweight street car and you have a combo that will run strong for years. Just like the T5's that won't survive behind a hopped up 347 or 351, we have loads of people on this forum that make it happen (they might baby it more than the guys with Tremecs but it does work). Realize that everyone will have an opinion. Do what you are comfortable with and what your budget will allow. Strokers are very common and if assembled by a good builder, with quality rotating assemblies, it will provide trouble free performance for years.