I just bought another 93 cobra and plan on doing a na stroker motor. I am really wanting to do the 408 with the possibility of a small shot of nitrous, but I want it to fit under a stock hood. Does anyone have a big cube stroker in a 93 cobra under the stock hood?
NA 408 or NA 347?
- Thread starter boosted93cobra
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i have a 90 lx with a 351w. Your stock hood will not work. You can get lowering motor mounts but you still probably will have to get an aftermarket hood. Well atleast i did for mine. I run a trick flow r intake with lowered motor mounts and barly clears my 2.5 cowl hood, but besides that it fits right in with no probs.
That sucks. I am really wanting big cubes under the stock hood. It would be a great sleeper if I could pull it off.
It can be done, but its not easy. Look up John Hartman (11sec_LX) on Corral.net or hardcore50.com
He has a NA 427W w/ a Super Victor EFI (read tall) that runs 10s NA under a fiberglass 'stock' appearing hood. It was quite a bit of work. He's a great guy to talk to and is very helpful.
I like my 427 under a small 1.5" cowl.
Anythings possible, just not easy.
BTW, go as big as possible for NA if your starting from scratch. Torque rules and the best way NA is displacement.
Let me know your plans/goals and I can give some advice.
I'm good at spending other people's $$$
Good luck, J
He has a NA 427W w/ a Super Victor EFI (read tall) that runs 10s NA under a fiberglass 'stock' appearing hood. It was quite a bit of work. He's a great guy to talk to and is very helpful.
I like my 427 under a small 1.5" cowl.
Anythings possible, just not easy.
BTW, go as big as possible for NA if your starting from scratch. Torque rules and the best way NA is displacement.
Let me know your plans/goals and I can give some advice.
I'm good at spending other people's $$$
Good luck, J
I already have a stock 1984 351w truck block that is in good shape, so I was going to use it as the block if I done the 408. I don't really want a radical motor, the car will be on the street 99% of the time. I planned to use the retro fit lifters and run a hyd. roller cam, so lash adjustments wouldn't need to be made once I set it up. I also do not want any bucking or surging, just a smooth running big cube torque monster that is comfortable on the street. The car will also keep the ac and power steering. I done a little research and it looks like it may fit with a tubular k-member and drop mounts, but the 408 is getting considerably more expensive than the 347.
I also have a mexican block and a 289 hipo block if I do the 347.
I also have a mexican block and a 289 hipo block if I do the 347.
JMO; but for heavy street use such as you state the car will see; I would definately stay clear of a 347; the typical pin location for 347 pistons results in oil consumption. The reduced stroke of a 331 (3.250) will enable a taller piston and negate the pin problem associated with a 347. Rod ratio is typically the same 331 vs. 347 but the slight added stroke for the 347 just is not worth it to me to burn a buncha oil on the street.
Don't worry about any oil consumption with the 347, most hight performance engine builders like coast and DSS have ringed and groved their setups and those problems have been eliminated.
For reliability I would go with the 331 because usually they dont generate as much top Horsepower and cause less stress on the internals
I like the engines that FPS sells personally www.f-p-s.com
Good luck with whatever combo you choose :coolman:
For reliability I would go with the 331 because usually they dont generate as much top Horsepower and cause less stress on the internals
I like the engines that FPS sells personally www.f-p-s.com
Good luck with whatever combo you choose :coolman:
9T3SVT said:Don't worry about any oil consumption with the 347, most hight performance engine builders like coast and DSS have ringed and groved their setups and those problems have been eliminated.
For reliability I would go with the 331 because usually they dont generate as much top Horsepower and cause less stress on the internals
I like the engines that FPS sells personally www.f-p-s.com
Good luck with whatever combo you choose :coolman:
Once again JMO; DSS and many of the other top notch engine builders have taken steps to diminish the oil consumption rate the 347s are known for but have NOT eliminated it all together; also at the cost of the pistons structural integrity. I would definately go with the 331 as you say though still for the less oil consumption and added reliability due to diminished side loading of the cylinder walls from the 347s stroke. This all coming to play due to this being a 99% street motor. However if the car was going to see 99% dragstrip then I would take that mexican block and stuff it with a 347 rotating assembly.
It IS possible to fit it under the stock hood, but quite a bit of work. Most do it with relocated motor mounts (using a tubular crossmember) and lowered engine mounts.
My plans are for a 302 based stroker if my motor ever lets go - I just don't want to add the extra weight on the nose of the car from the 351, plus no one will know any different from a 302.
My plans are for a 302 based stroker if my motor ever lets go - I just don't want to add the extra weight on the nose of the car from the 351, plus no one will know any different from a 302.
If I knew I could make the 408 fit, I definately would build it. The 347 doesn't really concern me about oil usage, I will be buying quality parts, so it should be fine. If I can get 400 rwhp out of a 347, I will just build it, but it would have to be completely streetable. I know this would be a lot easier with the 408, that is why I want to build it. Another plus is the torque that a 408 will generate. I wouldn't think that an aluminum headed 408 would weigh much more than a iron headed 302.
The heads would help offset the weight gain, for sure. I want to say that the 351 block weighs about 75# more than a 302 block. Aluminum heads weigh about 25# each, while an iron head hits about 50# each.
As far as streetable - yes, the 408 would be MUCH more streetable, and HP peaks would be lower, as well as torque peaks. It would be all in the heads/cam as far as where those peaks would be. However, plan on some serious tuning with either combo, as a simple calibrated MAF and big injectors ain't gonna be enough...
As far as streetable - yes, the 408 would be MUCH more streetable, and HP peaks would be lower, as well as torque peaks. It would be all in the heads/cam as far as where those peaks would be. However, plan on some serious tuning with either combo, as a simple calibrated MAF and big injectors ain't gonna be enough...
I was planning on a tweecer rt or an anderson pms. My last 93 cobra made right at 520 rwhp with a blower and a built motor, so I know how important the tune can be. It will make or break a combo.
I really want to do the 408, but the hood clearance is the only hold up for me. It really sucks, because once you figure in the price of a tubular front end and new hood, that alone is well over a $1000 by the time the hood is painted. That $1000 could buy a tweecer and a intake. If I could only make up my mind.....
I really want to do the 408, but the hood clearance is the only hold up for me. It really sucks, because once you figure in the price of a tubular front end and new hood, that alone is well over a $1000 by the time the hood is painted. That $1000 could buy a tweecer and a intake. If I could only make up my mind.....
408 is the only way to go! :rockon:
I think I will build the 408 and hope I can make it fit under the stock hood with a tubular k-member and drop mounts. I don't think I would be happy with a n/a 347.
Boosted, being a street vehicle, your concern with streetability is understood. I wouldn't write off the 8.2 deck motor, however. I see you are shooting for 400 rwhp. I feel it can be done quite nicely with a 347. Heck, my 306 a couple years ago made 402 rwhp. My current 347 is making 547 rwhp n.a., but is far from streetable, although I am still running a hydraulic cam. With correctly chosen parts, your goal is well within reach.
If I done the 347, I probably would use victor jr heads, a victor or tfs r intake, the mexican block with some sort of custom hydraulic roller cam. (Jay Allen or Ed, etc.) I would think that would be pretty streetable.
If I done the 408, I probably would use TFS r heads, spyder or tfs r intake, and custom cam. I think this could be equally as streetable and make 450 rwhp or so.
decisions decisions.......
If I done the 408, I probably would use TFS r heads, spyder or tfs r intake, and custom cam. I think this could be equally as streetable and make 450 rwhp or so.
decisions decisions.......
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