I didn't realize that in 1970 no mavericks came from the factory with a v8. Does anyone know if this puts me at a disadvantage for doing a 351w swap. I don't want to shave shock towers and from what I understand that doesn't help with header clearance anyways. My brother had this car and was able to fit a 71 grabber 302 motor into it with about a half inch clearance between manifolds and shock towers. my goal is a 94 roller block 400 FWHP narrowed 9 inch, 4 speed toploader, power steering, 4 wheel power disc brakes, 5 bolt 15 inch wheels and tires. and a grabber hood, not sure if it will clear 351 but can customize hood if its too tall. Any suggestions on parts specific to a 70 351w swap would be appreciated, also any known serious problems with this swap. The car is in great shape a few rust spots very strait body ill be using high port aluminum heads and trying to use the hedman 88300 full length headers. im not sure on which power steering rack and will probably be motor plates or similar bracing. any feedback would be greatly appreciated, thank you very much and God bless, wade
Real bad without shock tower mods. No room. Do a stroker 302 and get the HP and still have some room to work with. It's not easy working around a 351W in one of these engine bays. Here's mine when I got it with a 351W in it. SPark
a little too late for a stroker I already have block machined pistons and overhaul kit bought and heads are more suited to a 351, or I would do a stroker with the 71 motor that is in it. It looks like it fits . kind of, thanks I believe the 2 1/4" shock tower mod is looking better all the time. I do have access to all the necessary equipment. almost looks like problems with distributor clearance more than carb? Again thank you so much for the time and insight. God bless,wade
A 70 engine bay is no diferent than any other year Maverick - the small transmission tunnel, that is only in the 1970 model, could sometimes give you problems depending on the transmission/shifter that you want to use - one other thing is, if your key is under the dash, it is an early 70 model and that will have the tiny rear end that would have to be swapped for an 8 or 9 inch version
I know you're already heavily invested in the 351 swap at this point.. but I will still throw this out there. A hi-port 347 will still EASILY hit that 400 horse mark with some cam civility to spare. Or gear it right and get a good premium fuel tune(E85 is killer good with aggressive tunes and even higher compression is its best friend).. or you could easily push towards 450 with a bit less civility. The engine will fit better and the exhaust route changes are not as tough than the taller 351 will be. Tower shaves help.. but isn't a cure all. Header fitment is not known to be spectacular on these cars but there's quite a few headers that can be "made to fit"(those hi-ports will very likely screw you out of true "bolt on") to the 302 compared to the 351 swap. Custom may be your best option if you want a hotter/stroker setup down the road. Stroker 302's are about 60 lbs lighter than a 351w. This "high and over the nose" weight differential helps offset the slight advantage the 351 will have in higher average power production. If you like to corner hard.. that 351 will set you backwards compared to the 302. It's slight.. but it's something to consider. On the other hand.. the 351 gives you more stroke potential and has a wider/longer runnered manifold to make more peak torque and with wider power spreads. Screw the corners.. just go faster in straight lines until the next one comes.
Let me start by saying there is no substitute for cubic inches period. The main issue you will have with the 351 is header clearance. Tubular Automotive headers will work with just minor adjustments with a ball peen hammer. They are available from Autokrafters and other places. The other issue will be hood clearance, but if you don't get carried away with a tall intake manifold it will clear a stock hood. I love my 421W stroker. It makes good power but is not high strung. I idle at 800 rpm's and run a 12.34 @110mph. You can have your cake and eat it too. One final thought, a roller cam, either hydraulic or solid, is the only way to fly. Good luck with your build. Lee "THE MAV" Richart
Look at my "Pro Stock" thread for some ideas on the tranny tunnel with a top loader. You might not have to do as much with a street shifter but a good shifter like a Super Shifter or Ram Rod will not fit in the tiny tunnel. SPark
Great feedback so far, thanks I would think if a 3 speed toploader will fit with ease a 4 speed will also. I gotta say it right now, I don't plan on spending a lot of money on this project I have my engine budget at 2000.00 and so far it looks like that will happen. I do have the advantage of low machining costs due to shop foreman being a friend. I also have 4 mechanic brothers that have mig tig stick welders, lathe, small press break, tubing/exhaust bender and a lot of knowledgeable family members. I cant afford to buy a 700.00 steering box, or put 5 grand into a 347 stroker. I am by no means as knowledgeable as most on this post when it comes to mavericks and what will and wont work, and I really do appreciate all the help and suggestions and I hope they keep coming, but as far as no cutting corners and doing everything the right way with prefabbed kits and high dollar parts I just cant do it. I have to fight and cuss and learn how to fit square pegs into round holes on this project ;-). I do know that I need to get a decent steering box and probably power steering, so far I see this as my biggest obstacle, already have good front springs and I did decide to shave the shock towers down after reading the pro's of doing it. I plan on adding a quart or more to front sump oil pan. already have 8 inch rear, probably going to shorten a 9" and put current axles into it. Thanks again for all the feedback and I appreciate all the time taken to read and reply, God Bless, wade
The tranny fits in the tunnel fine. It's the shifter linkage that you have to watch out for. A Super Shifter/V-Gate/Ram Rod style shifter used a large diameter straight shift rod and there is zero left/right offset between the shifter arms and tranny arms. A street style shifter uses bent rods that follow the tranny body closer and buy you some room. Street shifter Race shifter Notice the different routing, size and shape of the shifter rods. Also notice how much higher and further back the shifter body sits on a race shifter, all to get straight throws. The narrow tunnel of the early cars don't have much room in them. SPark
wow nice pics ty yes I see the difference and I appreciate the large Hi def pics. Any suggestions on headers, the hedman 88304's look like they will work with minor mods, I don't have pwr steering yet and might just go with a manual box with better ratio, current is like 20 to 1 I believe and cant keep it on the road w 302 in it when I get on it in first, cant correct fast enough. I know a lot of ppl would suggest I keep 302 in it, but it has unknown miles and oil pressure a little low when idleing, it also took a lot of abuse at track when my brother had it. was sidestepping clutch at 6000 rpms lolz, getting under 14.1 in 1/4 with basically stock 71 302 4v. what headers are you using for your 351?
First off.. not trying to dissuade you in any way here but it surely helps to know all of the obstacles you'll face in this conversion process. The 351 is 3 inches taller(exhaust ports end up about 1.2" taller IIRC) and 2.25 inches wider than the 302. Then consider that things are already tight with a 302 in the first place due to these cars having narrower frame rail widths and tighter firewall clearance compared to Mustangs and other models of the era. Just going off what others have posted on this subject.. "minor mod'ing" another applications header is not quite what most consider to be a simple task. Of course, that depends on what you consider "minor mod's" to be. I figure more would probably do it if it was really easy to do. There are these Hooker 6208's which can be modded.. and Crites headers which supposedly bolt in to get better viewpoints as to the tighter confine's of this engine bay. I'm sure others have been made to work too as Maverick guys have a way of finding other shortcuts.. simply because they have limited parts availability.. and there are huge amounts of threads around here on this subject if you search. http://mmb.maverick.to/showthread.php?t=3049 Hooker 6901 mod here. http://maverick.to/mmb/showthread.php?t=75272&page=3 Also.. not really sure which one has what for dimensions.. but beware of 3.5 inch collectors if you're not running bigger stroker or major gear/rpm with the stock stroke. Not many combo's "NEED" a 3.5 inch collector until around 550 horses and above at this engine size/compression level. Smaller collectors help fatten up the midrange and keep the engine from being flat and hard to tune in the lower rpm ranges. A lot too small is almost always better than a little too big on any street type motor since it makes more average power. Last I heard.. Spark's car will have relocated towers similar to the old Pro-stock stuff and will have additional clearances compared to simpler tower shaves. Hope that get's you going further in this swap.
351 engine dimensions I know 351 ends up being quite a bit taller than 302 at top of intake plenum , but I thought it was only 1 inch wider at exhaust ports, I must have gotten some bad info I was going on the assumption that I would be 1/2 inch wider at exhaust ports than 302 and about 1.3 inches taller at ports also. I do plan on lowering the lower control arm and have read how to do it properly to keep proper geometry for best handling and alignment characteristics. maybe the 1 inch dimension was at top of block deck? again ty and God bless, wade
Apologies for not being more specific. That sounds about right as far as the exhaust flange location goes. My main point was that you're already space limited to begin with and this swap only makes it tighter. Shave the towers and mod a header to fit like many others around here have.. or buy the Crite's to save a little more time and headache.
