351w or 4v swap...

dnkapcorydnk · Jun 9, 2007

well im approaching the 250,000 mile marker on a bone stock, non rebuilt engine... i dont know how much longer its going to last and im planning my engine swap. How difficult would it be to swap a cobra 4v 4.6 into these cars? besides motormount, tranny, computer, anything else you guys think there would be?

Paul · Jun 9, 2007

Your entire accessory system, exhaust, bellhousing, gauges, etc. etc.

Not worth it. Go Windsor or built 302.

Suspect · Jun 9, 2007

+1

i say 351 or 302.

scarface · Jun 9, 2007

by the time you finished putting a 4v in your car you could have a badass pushrod engine in there.

Trickflow.GT · Jun 9, 2007

yea if your willing to blow all that money on a terminator motor go get a boss 302 block, billet crank rods and forged pistons, and a T-trim or a turbo set up...and blow all the terminators away!!

Paul · Jun 9, 2007

Billet crankshaft is unnecessary. You can make easily 1000 horsepower with a good forged crank in a race block.

But I do agree about the turbo smallblock.

slow96mystic · Jun 9, 2007

while it may be more expensive, the 4V is way better if it's a daily driver. My 96 Mystic and 94 gt put out about the same power (about 440 RWHP) but the Cobra is way more streetable at this power level. it drives like stock til i bury the throttle. You could probably find a 96-98 powerplant relatively cheap. Everyone always says "terminator" when talking about 4V swaps, but there are other alternatives.

Paul · Jun 9, 2007

I disagree. A very mildy modded turbo 302 (I mean stock or very small cam) can easily break 400 rwhp with little or no loss of driveability. Several of my friends have big (I mean mucho) horsepower SBF turbo cars and they have excellent manners. The right combination pushrod motor can be just as powerful and streetable as an OHC, and cost much less.

Paul.

slow96mystic · Jun 10, 2007

add up all the money you'll spend for an aftermarket block, rotating assembly, machine work, heads, rockers, exhaust, injectors, turbo kit, tuning, cam, and a decent clutch/transmission to hold your new power etc. I'll bet it comes pretty close to the price of a terminator drivetrain. I've priced them at right at $10,000. The truth is, neither route is cheap and it comes down to personal preference and what your goals are.

Paul · Jun 10, 2007

At 440rwhp (for example) he could re-use some of the stuff on his existing motor, including his block. You also don't need exotic internals at that power level. In either case, he'd need to spend money on driveline parts, so you can't count that against either. He wouldn't have to swap every accessory on the car. He wouldn't have to swap ECUs. He wouldn't have to figure out dash clusters. He wouldn't have to spend money on a swap k-member, swap mounts, swap exhaust, etc. etc. A pushrod motor will always be cheaper to build than a 4V monster, especially in a pushrod car.

Paul.

scarface · Jun 10, 2007

you also need to factor in the price of a Kmember to put in a 4v...they have different motor mounts.

dnkapcorydnk · Jun 10, 2007

well here is the deal. In about a year i will be attending S.A.M. (school of automotive machinist) right here in houston. When i go there i will be taking cylinder head porting and i will get all the practice i want literally. Part of being there is building my own project engine so thats why i was leaning towards the 351w. I can have my 351w block completely machined, do all my own cylinder head porting, and get the rotating assembly perfectly balanced and everything put together all nicely for free!!!! and i was planning a turbo either way. (i used to be an import guy shh!!!!) :rice:

AaRoN · Jun 10, 2007

351w FTW!

Paul · Jun 10, 2007

dnkapcorydnk said:
well here is the deal. In about a year i will be attending S.A.M. (school of automotive machinist) right here in houston. When i go there i will be taking cylinder head porting and i will get all the practice i want literally. Part of being there is building my own project engine so thats why i was leaning towards the 351w. I can have my 351w block completely machined, do all my own cylinder head porting, and get the rotating assembly perfectly balanced and everything put together all nicely for free!!!! and i was planning a turbo either way. (i used to be an import guy shh!!!!) :rice:

I have a 422 windsor in my car - so if you need advice about options, combinations, and staying within your budget - I can help.

That's cool that you're going to learn to be a machinist. I would love to learn that trade. Maybe someday if I can retire early I will still do that.

Good luck!

AaRoN · Jun 10, 2007

a 422?? how much tq you pushing to those wheels???

Paul · Jun 11, 2007

Old motor (mild 418) made 442 rwtq naturally aspirated, and 615 rwtq on 150 shot.

The 422 hasn't been dynoed yet. It has much less compression though, so the NA numbers probably won't be as good.

slow96mystic · Jun 11, 2007

Always is such a strong word..... I was discussing if his eventual goal was over 500 rwhp then the two buildups wouldn't be that different in price. I rebuilt my 302 with dss pistons and girdle with all the supporting boltons. this was definitely cheaper than a 4v swap. BUT then i decided i needed more power..... vortech supercharger, injecters, MAF, fuel system upgrades, tuning, a new transmission (since t-5's aren't that strong) and clutch all add up to about $5500-$6000 not counting installation (did it myself).
Add that to the cost of rebuilding a 302, heads, cam, intake, and other misc. parts and you're not far off. AND the terminator motor can hold several hundred horsepower more than a stock 302. As i said before, it's personal preference, but since i have both motors and have had to pay to modify them i can say that ALWAYS is not always the case. It depends on where you're trying to go with the car.

Paul · Jun 11, 2007

Once again, you're not factoring the cost of replacing the ENTIRE accessory setup, gauge cluster, k-member, etc etc...

It will ALWAYS be cheaper to build up a pushrod motor in a pushrod car. ALWAYS. ALWAYS.

slow96mystic · Jun 11, 2007

You can buy a "Terminator" motor complete with all front accessories, T-56 Transmission, and cpu/wiring harness/gage cluster for about $10,000. How much are K-members? you can still use your springs if you buy the perches. I was trying to discuss long term and the fact that a terminator shortblock can handle tons more power than a stock 302. I've gone the 302 route and have at LEAST that much invested in it. Oh well, guess i'll just go back to corral, where I may not ALWAYS be right but at least the people aren't all closed minded. :'(

scarface · Jun 11, 2007

slow96mystic said:
You can buy a "Terminator" motor complete with all front accessories, T-56 Transmission, and cpu/wiring harness/gage cluster for about $10,000. How much are K-members? you can still use your springs if you buy the perches. I was trying to discuss long term and the fact that a terminator shortblock can handle tons more power than a stock 302. I've gone the 302 route and have at LEAST that much invested in it. Oh well, guess i'll just go back to corral, where I may not ALWAYS be right but at least the people aren't all closed minded. :'(

Im sorry you want to leave but you asked our opinion. Why ask if you dont want to hear it? You obviously have decided on the termy engine, so good luck with your build and keep us posted on how it goes.