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10.5:1 on 92 octane ?
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Posted by: Tang

Well the stang just died, and I am coming into a little bit a of money to work on it with.

I want to do a cheap rebuild on my '69 351W I have and stick it in it. Get one of those Summit rebuild kits that has everything. I'm pretty sure it will work fine, but will I have any trouble running 92 octane with 10.5:1 compression ?

Gonna be using the stock '70 casting heads, I know that sucks, but cant buy heads for it right now. Havent decided on EFI or going carbed.

The first issue witht he car is the trans. The bell housing busted and one mounting ear broke off the trans. case.

But, if i use the 351, and go carbed, it will have either BBK 1 5/8" shorty headers or BBK 1 3/4" Long tubes, Comp 280 xtreme cam, Weiand Stealth intake and a 750 Edelbrock carb. With the 10.5:1 rebuild. I will probably just get the rebuild kit with the Hypersucky pistons because I have no plans for nitrous or a blower.

I could go EFI since I already have a 73mm air meter and a 70mm t-body, but the swap intakes are pricey and I need new fuel rails I believe.

Anyway, Grape , I think this is your area of knowlege, jump in here and give me some advice. I know it wont be no power house with the stock heads, but it will definetly have more power than my 302. With the 2 barrel the 351W was rated at 260hp at 9.5:1 and 290 with a 4 barrell. Surley with the parts I listed will get me near 375.

Posted by: LS1JAY

I would think you could get by with 93 octain, maybe not too good on hot days, then again you live in VA so you should be okay.

Posted by: RacingJason

Sorry to burst your bubble...10.5-1 with the C9 or D0 castings is like asking for spark knock, and lots of it. The chambers of those heads just plain suck, then factor in the restictive exhaust and it will sound like a diesel on hot days!

The power estimate is a bit high too, unless the heads are seriously ported. And lastly the 10.5-1...be sure about this. They love to give approx ratios using the 58cc 289 heads. And for goodness sake...PLEASE...PLEASE use forged pistons in this engine!! The cost is not much more in the whole scheme of things!

Send me a PM if you want some help...I do this stuff all day every day. (it's my job)

PS. The 69 is the best windsor block ever to leave the factory.

Posted by: 86pushrod

10.5:1 with iron heads!!!!!:roll: don't see that makin it with pump gas unless you take all the timing outta it...375 hp also seems a tad high.. more like 325-350 with a good tune. i run 10.65:1cr with aluim. heads on pump gas no prob but then again those heads you have are iron so i wouldn't run anything over 10.1 also run the forged pistons... hyper suck period. ive seen em crumble before just from a high reving solid roller n/a combo..

86~

Posted by: Tang

Well I done some thinking. My Z28 had around 350hp in a 3600lb car. It was a blast to drive. So I suspect 350hp in a 3200-3300lb car would be even more fun. So whats the quickest and easiest way to get 350hp from my 302. Intake and heads ?

For you newer guys that dont know my Mustang, its a '92 GT . It has :
73mm C&L air metere
70MM Edelbrock Throttle Body
B-303 cam
cold air kit
no cats
turbo tube cat-back
although it still has the stock shitty headers
3.73's, Hurst, blah blah blah

Is those 351W heads gonna be worth using on the 302 atleast ? If not Im gonna stick them on Ebay.

Posted by: 86pushrod

i tell you how my freinds stock bottom stock cam! factory stock 91 hatch puts out around 343 fwhp and runs 12.3's... beside him having a spool and 4.10's with descent control arms and shocks f/r... the motor has pullies,shorty headers,prochamber,1.72 rockers,gt40p heads with a competition valve job on em,cobra intake,and a accufab 70mm t/b...other than that its stock still has a/c and w/p fan on her... if money isn't a huge concern but you don't want to spend a ton get some dart or world heads w/ a valve job..run somthing along the lines of an edelbrock victor or typhoon intake and get a custom hydro cam off anderson motorsports.... im running the n-111 hydro in my 352 and i spin it up to 7300 rpm with the crane vertical linked lifters(even more when i get some titanium valvetrain gear)...

good luck with your combo.. makes sure to free up some hp off the belt drive.. (ditch the power steering + a/c + fan)

86~

ps. the best way to go about it if ya can afford it would be an aluim. head + intake combo port matched and a custom cam... that should put you right around 375+ with the right tune.

Good luck

Posted by: Tang

I want to have 350 hp in street driving trim. I have the the air pump by passed, and im gonna take the AC off asap.

I cant find the Windsor SR heads anymore in cast iron.

Posted by: 86pushrod

for the money you can't beat ported gt40's although im not a big fan of em as they don't do what aluim. heads can for a few more bucks...

Posted by: Grape Ape

I guess I'm late on this... It's covered well though, really.

Sticking with the 302 isn't a bad idea, sicne you'd be in for a world of new things needed to do a 351W swap. If you don't have plans to sroke the engine, it's not quite, but almost pointless to do this swap in a street driver, thanks to the aftermarket available.

Making 350 reliable and daily driveable rwhp on motor alone isn't very easy without a stroker, while using a 302HO. Stick with EFI. No power adder at all? Well, okay, but you'll want nitrous later..

Here's what I'd do, considering a budget build. Well first.. Fix, replace or whatever, that T-5 and seriously look into a Tremec 3550 and think about a Pro5.0 shifter too. Substitutes are EXACTLY that...remember that. Get sub-frame connectors. You'll need them. Also get a D/S loop then, if you can...you'll need it too.
Step one: TFS Twisted Wedge heads and associated parts(roller rockers, pushrods, etc.) and a new cam. Get something with a split duration just because.. The Steeda 19 isn't a bad choice, but there are probably a couple out there that offer a bit better overall power than it usually will.
Step two: aftermarket intake of choice. Nearly any will do, as all are better than the factory unit. I like the good ole Edelbrock Performer 5.0, but I'd go with the RPM, since it's better. Of course, there's all those others to choose from, TFS standing out among the crowd(for price as much as anything), but it's large and heavy.
Step three: MSD ignition system(complete except for distributor because the factory one is excellent).
Step four: long tube headers. Heck, shorties will do, but make them 1 5/8" instead of the stock ones. And make sure you have a 2.5" exhaust system, mandrel bent.
Step five: Consider losing the CAI because it's basically useless under 85mph anyway. Drop excess weight where you can, like the 40 or so pounds of sound deadener the car was graced with from the factory. Make sure the rear tires are decent too.

These changes won't NECESSARILY net you 350rwhp, but they will probably help you see well over 300(325-335range) and once you learn how to drive with these mods, your car should EASILY run 12.70's in the 1/4 mile WITHOUT slicks.

If you can't get new heads, see about what you really havethere... Those early W heads had larger valves than the post 74's, so you may have a decent START with them. However, they'll NEVER be the best available, no matter what you do to them. Using them should also require a new set of rockers, so consider that a good reason for replacement aluminum heads. TFS are simply the least expensive and they HAPPEN to be as good as any you'd need on such an engine.

That's 2 cents worth if I ever saw it!

Posted by: Tang

Thanks for the advice. All good except the Pro-5.0 shifter. I broke the handle on one of those. Snapped it off where the threads go onto the flat stick. I replaced it with a Hurst Billet/Plus and havent regretted it.

I didnt mean 350rwhp, I meant 350 at the flywheel, 300-305 at the rear wheels.

Quote:


	Step five: Consider losing the CAI because it's basically useless under 85mph anyway. Drop excess weight where you can, like the 40 or so pounds of sound deadener the car was graced with from the factory. Make sure the rear tires are decent too.

Well, mine isnt actually a cold air kit. Its a March Ram Air kit without the bottom scoop. The bottom scoop kept cleaning up the highways for the state. I had gum wrappers, leaves and bees in my K&N.

Posted by: Tang

By the way, my motor, internally is in good shape. No knocks, rattles or smoke. But I am however gonna have to re gasket the whole thing. I might just have it bored .030 if the previous owner didnt when they rebuilt it.

Posted by: Grape Ape

Quote:


	Originally posted by Tang Thanks for the advice. All good except the Pro-5.0 shifter. I broke the handle on one of those. Snapped it off where the threads go onto the flat stick. I replaced it with a Hurst Billet/Plus and havent regretted it.

Well be that way! :btg: They're stronger than ever now, but OK. The size as well as design of the Hurst makes them work well. I used one for several years. All I ever broke was my transmissions.. heh

Quote:


	I didnt mean 350rwhp, I meant 350 at the flywheel, 300-305 at the rear wheels.

Then this is easy...

Quote:


	Well, mine isnt actually a cold air kit. Its a March Ram Air kit without the bottom scoop. The bottom scoop kept cleaning up the highways for the state. I had gum wrappers, leaves and bees in my K&N.

That's how most work!

You may as well remove it though. At this point all it's probably good for is making a whistling noise.

Posted by: Tang

I always figured it was the same as a cold air kit, atleast it isnt breathing under hood heat.

My 19lb injectors are only good to what ? About 325-330hp ?

Posted by: Tang

So you say the B cam aint gonna do it. Whats better, GT40X or Twisted Wedge heads ?

If I knew I'd have the cash I'd opt for some AFR 185's

Posted by: Grape Ape

I've seen a car make 320rwhp with stock 19's. Personally, I'd use 24's for your car, with the other upgrades. I even started to type that, but then got side tract last night(it was late, I was tired).

Twisted Wedge are much, much better than GT40X's. I've had each on the same short block and the car was definitely more powerful with the less expensive, TFS heads.

The B-cam isn't terrible, but it's not as good as it could be. Split durations just seem to do better.

Oh yeah, and the 185's might net you another 3hp over TFS TW's, at a cost of about $300 more. It's hardly worth it in my opinion.

Posted by: 86pushrod

i had a bcam set up once.. trw 10.1 cr 306 gasket matched e7 heads long tube 1 5/8 mac's with bullets no a/c or smog on belt w/ a t5 and a mac cai..with a good tune taylor wires and pullies the s.o.b. made 245 rwhp... not bad for 3k... with 3.7.3's

i had a buddy use a b303 in an auto and the car was a pig... lumpy idle and no low end.. my idle was terrible i have to admit with the speed density... people swore i had a super charged humongo cammed big block... i laughed when i told em it was simply a loud 306... 13's were the norm. on slicks
13.11 being the best on stock control arms!!!

on a 302 your heads will simply make or break the hp.. the stock cam is a really good peice & 1.72 rockers help it even more... but w/ better heads a custom cam will wake it up.

as far as 19lbhr inj. go ive seen 350 at the fly... no lean problems until 5700 rpm and that was fixed with a boost a pump from kenne bell... stock pump sucks ass... so do the stock lines by the way.

86~

Posted by: Tang

Ya know what, I think I'll just piece the POS back together and drive it until it finishes falling apart. I only gave $3300 for it back in '98 anyway.

It hardly seems worth all that effort.

Posted by: MikeT

what exactly went wrong?

Posted by: Tang

Bellhousing cracked where the clutch cable attaches, so the clutch wont disengage. One mounting ear broke off the transmission itself. And it had been having wiring problems.

Im just waiting for the mufflers to fall off so you can pick at me...lol

Posted by: 86pushrod

don't give up man,... unless you want to pimp an import.... cars are ment to be hard work...if they wern't everyone would have a fast one.:sad: bellhousings are cheap get one from a junkyard... as far as the tranny ear is concerned.. you could fix that with a welder and some angle iron... cheap way.. its funny i have quite a few freinds down in fl with stangs, and one in particular wants the fastest car in the world but doesnt want to work on it,... just says he does. every time he drives it he beats the dog piss outta it and when shit breaks he blames ford!.... imo don't deserve a fast car...all im sayin is i know this shit can get ya down sometimes but either your into it or your not..... trust me you'll never have what ya want if your inbetween.

Posted by: RacingJason

Get a T5 case and make yourself a whole trans. Then forget everything you have heard about GT40-X/P heads. Find some newer style TFS TW heads (used works too) and use a cartridge roll to blend them yourself, just minor work. Then score a Performer RPM rip off intake, again with the blend job, bolt it on with the stock cam and ride out.

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