Roush engine ?

[cobrarob]

Hi guys

I know the roush engines are widely discussed on this forum and I think the information I am looking for will be here

I am trying to decide which Roush engine to install in a new Superformance Mark 111

I beleive I would like to go with the 402"S"R"TW" as I have heard that the 402 is a little more streetable than the 427.

I have also heard that the "S" stands for a split plane manifold , I could be wrong on this , biut either way I would like to know the advantages and disadvantages to this engine modification

I have also heard that the "TW" stands for a twisted wedge cam and I would like to know the advantages and disadvantages of this engine modification

I am looking for the most relaiable engine combnation with a carb , I am not using the car for anything other than cruising and I really dont want to have to experience run-on

Nothing worse than pulling up to your favourite watering hole and have a crowd gather and when you shut the engine off the car runs-on , pretty embarassing by any standard

I have heard that carburator technology has come along way on modern engines and in particular on roush engines , in my experience I found engines with high horsepower and carbs had to have a constant level of attention to keep them running and avoid stalling at low idles , any comments ??

[Ron61]

Just on the split plane manifold. They are better I think for normal driving and low end power than the single plane ones. I have had both and I believe the single plane made more power but at a higher RPM. I never had any problem with either so far as engine run on. I had over 500 horse in the Cobra that I sold and it had the single plane. The 69 has 440 horse and the dual plane and I hardly ever touched or had to have any tuning done on either of them once they were ran and set.

Ron

[madmaxx]

Go with the 427sr/tw.

1) It is a 427 like you fender badges will indicate.

Completely streetable with no issues. SR stands for street rod. The only difference between the sr and sr/tw is the twisted wedge cam, intakes are both eddlebrock performer. The r has a different manifold and different cam, no quite as streetable. I was hooked on a 402 until everyone kept asking me what the heck is a 402, you are paying for the dart block you should get all the cubes you can out of it

[mln385]

I have the 427 sr/tw and it is quite street friendly so far with 750 miles on it.

[Hammer65]

I agree with madmaxx. The SR has a flatter torque curve which appeals to me for street driving.

[Got the Bug]

Originally Posted by madmaxx

Go with the 427sr/tw.

1) It is a 427 like you fender badges will indicate.

Completely streetable with no issues. SR stands for street rod. The only difference between the sr and sr/tw is the twisted wedge cam, intakes are both eddlebrock performer. The r has a different manifold and different cam, no quite as streetable. I was hooked on a 402 until everyone kept asking me what the heck is a 402, you are paying for the dart block you should get all the cubes you can out of it

Or go with the 402 SR TW and don't put any emblems on your car.

What's the price difference these days?

[vegasmike]

I am 200 miles into ownership and love the 427 sr/tw. I will say this though, the car would rather go fast/accelerate than go slow under 2000 RPM's, but I have not had any problems driving in traffic. I have yet to stall it out and have not experienced any run-on at all.

Just make sure you have a good dealer and installer. Where are you located?

[greg schroeder]

I set up my Superformance with a Roush 427R with single plane intake manifold and Pro-Systems mechanical secondary carb. Power and drivability exists at all RPM ranges, power is smooth at any throttle position or it hits like a hammer when the throttle is mashed and you can fart along in the 1600 to 1800 rpm range in 5th. It pulls like a mother from idle up to just below 7000 rpm. At the wheels it makes 475 HP and 460 TQ with a fantastic torque curve for performance. I have a dyno in my image gallery or check out the 10.7 @ 130 mph drag pass in my sig below.

Quite honestly I believe the carburetor selection and tune is more important than which engine.

[native1]

I have 427 srtw and I love it. 3700 miles no probs. I added vic jr intake and 950 cfm carb. Yesterday it made 467rwhp at local shop. Check my post from yesterday. SRTW pulls from down low all the way up to 6400+- If you do the roush I would still advise a new carb with mechanical secs. I would also advise on the 427 not the 402. For resale if anything. There are no probs with streatability. Mine has only run on a few times, just pop the clutch in second to seize engine after shutdown. A friend of mine has a bdr with the roush 402r. His only regret is that he did not go with the 427!!!!

[mln385]

Originally Posted by native1

I have 427 srtw and I love it. 3700 miles no probs. I added vic jr intake and 950 cfm carb. Yesterday it made 467rwhp at local shop. Check my post from yesterday. SRTW pulls from down low all the way up to 6400+- If you do the roush I would still advise a new carb with mechanical secs. I would also advise on the 427 not the 402. For resale if anything. There are no probs with streatability. Mine has only run on a few times, just pop the clutch in second to seize engine after shutdown. A friend of mine has a bdr with the roush 402r. His only regret is that he did not go with the 427!!!!

I had run on ......my curb idle was 1200-1300 so I turned it down to 1050 and now it idle's fine and no run on.

I too had originally ordered the 402 sr/tw but changed my mind an I am not sorry.
However if you want fuel economy this is not the motor to go with as at best you are 14 mpg with the tremec 600 5 speed.

Marc

[JWilly]

I have the 402R and have no 427 envy problems. It took me forever to decide between the 427 and the 402. The reasons I went with the 402: The 500+ hp it generates and the torque it produces is plenty, you'll (probably) never use all of it on the street. There does not seem to be a lot of difference otherwise between the two engines (same bore, slightly longer stroke for the 427). Both are small block engines. Even if the numbers are 427, it ain't a BB 427 FE. People are always asking some version of the "is it real?" question and I I really did not want to re-explain, time and time again...yes it has 427 cid but no, it is not a BB 427...(I realize this reason is pretty lame). I have no badges on mine but should I do that I'll use a "powered by Roush" badge. Should I decide to sell it, I hope the fact that it has a Roush engine will help it sell. However, those who say a 427 Roush may be easier to re-sell may be correct, I do not know. You do pay more up front for the 427, I do not know if you recoup more of that with a 427 than with a 402.

I do like my 402R. It is crazy fast, does not overheat, is reliable and it sounds great. What ever you choose, it is going to be a load of fun. Do what feels best for you. when people ask about my engine, I simply state it was built by Roush Racing and they always smile. I don't have to say any more.

[madmaxx]

427 is about 2K more than a 402. I guestimate 700 427's have been sold to 300 402. I drive all day long in 3rd and 4th gear around 1400-1700 rpms with no issues, never had any run on issues either.

bb or sb it is cubic inches, 427 hell pull a 502 out an old caddilac and you have a big block. your car is technologically advanced your powertrain should also, i guess we should leave out the hardnend valve seats also.

[SP01715]

You can't go wrong with Roush whatever engine you decide on, but I think all the motors make good street mills. My motor is almost identical in set-up as the 427R (heads, intake etc...) but has a more radical cam and it never gives me any problems on the street. Cruising is not a problem and it always runs cool. I would go for the 427R if it was me, but they are all good motors.

[Got the Bug]

Ditto what JWilly said. Go for the chrome "bling" as well.

Guessing there's little difference in gas mileage between the Roush 402 and 427. The best I've gotten is about 14 mpg with the 402.

[Cobra #42]

Have Roush 427-542 with 3200 miles, Pulls hard and sounds great, no overheating in Texas 100 + degree days in heavy traffic. Go for the bling, db

[vegasmike]

Yea, I am guessing I get around 14 mpg, but it really depends on how you drive it. My Roush 427 SR/TW engine is #666 (yea, nice #) and it was delivered in May, so the 700 guess should be close. Mine is polished and, like I said, I love it.

I was out driving yesterday and came up to a stop light with a few other cars including a Vette. At the next stop light I was directly behind the Vette and he tried to pull away when the light turned green. I stayed with him quite easily and he pulled into the turn lane at the next light, right next to me. He turned to me and said one thing, "you were playing with me, weren't you?" and shook his head. I have still not grounded the right foot pedal.

I also had a kid pull up next to me at a stop sign the other day and rev his engine in his 5yr old mustang (obviously with some after-market work done). Once I shook my head that I was not going to race the kid, he slowed and did a U-turn. I might have played with him a little, but I had an 85 yr old Great-grandmother in the passenger seat. She just laughed.

[BLUE427]

Go With The 427, I Dont Regret It, The Roush Name And The 427 Will Help Sell It If You Ever Need To , Or Want To. The 427 I Have Is Very Streetable And Has Alot Of Power Also, Great Sound, And FullY Polished option Is A Nice Way To Go To (imho)

http://www.clubcobra.com/photopost/s...hp?photo=58934

[ekrupa2]

402 SR/TW...not polished. No regrets. My goal in the next year is to ditch the Holley Avenger for a Pro-systems carb. If you have specific questions PM me and I'll give you a number to call.

[tomcat racing]

hi from australia, just picked up the roush debate, maybe someone can help me as you all have roush engines, i want to buy a roush billet oval air cleaner part no 401386 from j c whitney, i have emailed there international shipping sales dept several times for no answer. will they fit a barry grant 850 and where can i buy one to ship to australia to fit my ac cobra, i think they look smick but ive come to a dead end. also what type of filter do they come with. kind regards tomcat, downunder

[native1]

Originally Posted by tomcat racing

hi from australia, just picked up the roush debate, maybe someone can help me as you all have roush engines, i want to buy a roush billet oval air cleaner part no 401386 from j c whitney, i have emailed there international shipping sales dept several times for no answer. will they fit a barry grant 850 and where can i buy one to ship to australia to fit my ac cobra, i think they look smick but ive come to a dead end. also what type of filter do they come with. kind regards tomcat, downunder

Jegs has them part# 832-401387. They probably send international. Mine is about 5.25 inches diameter at the carb base. Good luck