400hp 351w

[mustangfreak88]

I am planning a 351w swap for my 88 gt this winter and i was wondering what i need to do to get 400 hp to the wheels. This will be a carb motor and n/a. I was looking for a cam with a rough idle but streetable since this will be only a street car. just looking for some input on what i should do. my budget is a couple grand so i cant go too crazy. thanks

 

[squeak93]

First off, what year block do u plan on using? Pre 94 are non roller block. 69-74 are the strongest and can save u some money as far as durability. They have the strongest factory rods and a pretty good crank. This way u can just have ur crank mic'd and turned if needed, recondition ur rods and throw in the appropriate set of forges pistons. Try not to bore the motor unless needed, the few extra cubes will not net you any noticable amount of power. Second, depending on roller or tappet cam, u will pronbally want to go custom grind. Comp now makes the Thumper series cams but they are roller only, they have a very nice healthy idle with great street manners.

You really need to invest in a good set of heads, either trick flow or afrs 180s at least. Your motor is going to want some major air, so don't forget about upgrading ur fuel system to match. If your car is efi right now ur looking at all new fuel lines, pump, regualtor, tank insert (unless ur good at fabricating). So plan on quite a bit of money just for the supporting mods it takes to have a 400 hp car.

You also need to consider your suspension. If you put 400 to ur car now w/o any other mods ur looking at one scary, dangerous and very inefficient set up. You need sub frames, upper and lower control arms, most likley different gears and a trac loc rebuild depending on the shape of ur car now.

I guess I need more info on ur car as it is now to help more. I am about 2 months a most away myself from doing this exact set up on my 92. I can tell u I have a great parts list compiled, I am planning on using my stock heads d4 casting on block and heads (1974 last year for strongest blocks) I am at about 4500 in parts so far and I am using good middle of the road parts with a nice comp flat tappet cam (pretty close specs to the trick flow 2). So u can do a 351 swap for a few grand but u will most likely not get anywhere 400 to the wheels. Use the tread at the top and look for the 351 swap. There are a ton of odds and ends to buy. Plus u have to think about ur tranny. Either auto or t-5 it will not hold up to 400 unless you have already built them.

 

[mustangfreak88]

i was planning on trying to find a junkyard engine, but i do know i want to go roller. i was planning on new gears, suspension work, tranny rebuild(have a t5), and upgrading to fuel system so im prepared to spend money there. i pretty much have a stock stang besides a exhaust setup and cobra intake

 

[PUNISHER RACING]

400 horse is real easy in a 351 based motor. First off the stock crank and even rods in a 351 can stay and be remachined they are pretty tough. You will need a cylinder head of any variety in the 185 to 200 cc range. A set of hyper flat tops will keep it quiet and durable n/a and with a 58 cc chamber head will give you about 10.1 comp. ratio. A comp cams Xtreme energy cam part # 31-254-4 on a 110 is a cam we use often and provides a good lope and a nice power range. Top it off with a Stealth intake and a 750dp and you got one nice and mean street car. This is a basic $2500.00 reliable street engine with some serious grunt

 

[squeak93]

You pretty much need a whole new tranny, gear set and such. T-5's can be made to handle that kind of power but ur looking at a ticking time bomb. I would look into a 3550 swap or t56 is money allows. Thats just me, others love the t5. I love the way the t5 shifts compared to the 3550 but they are night and day as far as quality.

Your going to need many new parts. U can source some of this from a junk yard. The thread in the "usefull thread index" at the top of the forum will tell u exactly what parts u will need. Except for the distributor, that u will have to find on your own. Depends on what year engine to what dist u get, not to mention if your goin carb you have to decide on mechanical or vacum advance.

Take you time, spend money where it needs to be, dont skimp on parts, u will hate urself in the end. I was going to try to due a budget build at first until I made a spread sheet with all the parts that are just needed, man, it was a ton of stuff. Now u can go junk yard hopping and save some money, but I want it done right the first time.

Things u will need to go carb 351
Oil pan. Swap headers, Front brackets with spacers. U will needs 28 ounce ballancer and flywheel, lower intake for 351, distributor, some type of ignition (ford duraspark from a junk yard car is more the sufficient if you get all the pigtails along with the box) u will need a new fuel pump ( dont use the efi one, even if a buddy tells u its ok to do so, it will most likely harm ur carb) You will most likely need a new clutch as ur stocker will go quickly with the new found power (might as well do it while engine and tranny are out).

There is some more stuff but I am drawing a blank right now. Overall, plan on 2-300 for a good block. (maybe more for a roller) about 2-300 for block work depending on shop, quality and area u live in. 500 for a forges piston rebuild kit from summit (includes bearings, gaskets, freezeplugs and something else I'm sure I'm forgetting). You need to either get a good set of older heads and spend some major money to get them ported (or do them yourself if you can, but can be costly if you mess them up) Save up for aluminums, and have them ported so u can get the power needed. You will needs some good valve train componets (springs, roller rockers, pushrods, and seals and such) plan on 4-500 here. Then you have to find ur carb, a nice holley 4150 double pump 750 can run anywhere from 350-1k depending on options. The basic one is just fine. probally want an electric choke for ease if you drive in the cold. You need a good lower intake, most of the edlebrock lowers are good, make sure u find one the pulls to 6500 if u want to go that high, alot of them only state the power range to 5k or so.

If you pm me your email address I can send you my spread sheet when i get home to give u an idea on what your looking at. Can't do it now as I am at work. Just remember to read up and ask questions.

Who is going to be assembling the engine?

 

[mustangfreak88]

this info has been a big help and gives me an idea of what im in for thanks. i will be assemblying the engine myself.

i have another question, are the 351w and 302 camshafts interchangeable if i get a roller block or convert a non roller to a roller?

 

[PUNISHER RACING]

Yes the cams are interchangable it is just the firing orders that are different. The 302 HO and 351 share the same 13726548 fire order and the older 302 flat tappets have a 15426378 order. They are the same size though. I will tell you now if assembling the engine yourself I cannot stress enough cleanliness is key and remember to check things twice or even three times if you have to. If you need any advice or tips give me a holla. Have fun and measure twice cut once and the reward will be great.

 

[85_SS_302_Coupe]

400 horse is real easy in a 351 based motor. First off the stock crank and even rods in a 351 can stay and be remachined they are pretty tough. You will need a cylinder head of any variety in the 185 to 200 cc range. A set of hyper flat tops will keep it quiet and durable n/a and with a 58 cc chamber head will give you about 10.1 comp. ratio. A comp cams Xtreme energy cam part # 31-254-4 on a 110 is a cam we use often and provides a good lope and a nice power range. Top it off with a Stealth intake and a 750dp and you got one nice and mean street car. This is a basic $2500.00 reliable street engine with some serious grunt

I like all of that except i'd go the extra distance and get forged pistons in case i wanna spray it, and i'd probably try for a custom cam if the budget could afford it.

 

[85_SS_302_Coupe]

this info has been a big help and gives me an idea of what im in for thanks. i will be assemblying the engine myself.

i have another question, are the 351w and 302 camshafts interchangeable if i get a roller block or convert a non roller to a roller?

The cams are interchangeable only if you're going from a roller 302 HO to a roller 351W. If you convert the older non-roller 351W to a roller cam you have to use the special small circle base cams because the rollers are longer and actually come down into the cam's space and necessitate a smaller lobe to make up for it. This will work of course and a lot of people do it, but you're pretty limited to cam selection. I would either find a factory roller 351W (you can find them in the early '90s F150s in junkyards) or stick with the flat tappet.

 

[squeak93]

The cams are interchangeable only if you're going from a roller 302 HO to a roller 351W. If you convert the older non-roller 351W to a roller cam you have to use the special small circle base cams because the rollers are longer and actually come down into the cam's space and necessitate a smaller lobe to make up for it. This will work of course and a lot of people do it, but you're pretty limited to cam selection. I would either find a factory roller 351W (you can find them in the early '90s F150s in junkyards) or stick with the flat tappet.

I 100% agree on the forged pistons. Its well worth the extra piece of mind for less than 200 bucks.

Second, the price of 2500 is pretty good, but remember to budget for the car upgrades as well. They can run just as much if done right, or u can do what is needed right away (tranny and fuel) and then upgrade the supsension as the money allows. Just keep you foot out of it as it can get pretty hairy skating down the lane at the track.

 

[Fox8950]

Vristang has an awsome writeup on this check out http://www.freewebs.com/vristang/fox351wswapfaq.htm ... helped me get going in the right direction, 69 and 70 blocks are the strongest as you'll see in his writeup, almost sold my 69 block till I read this and decided to build it.