Need help deciding on an engine block!!

93 Cobra needs input · 10-21-2002, 07:52 PM

Finally getting the stroker together this fall and I have ran into some block and price problems what do you guys think? First option, factory block machined locally with stud girdle, although cheap I fear the worst with a supercharger and high dollar rotating assemble. I wanna start at 9psi maybe a little more in the future. Second option Keith Craft will send me a new 302 blueprinted and bored with torque plates line honed and clearenced with arp main studs installed for around $750 I talked to them about a sportsman block thinking it sounds like a happy medium and they said the block is basically the factory 302 with a little better main caps and that I should go with the R302 block to have absolute no worries with boost and HP The problem is they want $2450 out the door for an R block ready to install with all the fancy machine work done. I'm leaning towards the new stock block with good machining. I know the block it the foundation for all the other parts but I think that R-block is a little steep. Can someone here convince me to go with the R block I don't have tons of money but I really want my car to have a ton of HP and not have a lot of worries about throwing a rod or breaking a main cap. Sorry this got so long!

302 LX Eric · 10-22-2002, 08:38 AM

My quick analysis and opinions...

1) Are you running 10:1 compression? If so, watch out throwing 9psi or even more at it...

2) A well built/machined stock 302 block with T6 6061 Girdle (like what DSS sells) with all ARP, etc. should hold up fine to 500 HP, maybe even 550 HP. Over that and you're pushing the envelope. Also, are you going to be dropping the clutch at 5500 with slicks out back and a drag suspension? If so, then look into the R-Block, over than that you should be fine.

3) DART also has some new blocks out there, but I think they require high dollar machining as well - but not sure. Just another option to consider.

4) Lastly, (and maybe this should have came first) what do you want out of the car in the end? That is the ultimate question that will determine whether you need to plunk down the big $ for the R-block or stick with the trusty stocker.

E

LX XLR8R · 10-22-2002, 11:27 AM

my opinon..grab a 351 from dss..my 408 with girdle,custom pistons, steel crank and steel h-rods and ARP'ed out will support 750hp..thats a happy median to me..total bottend end cost with low compression pistons is $3500

93 Cobra needs input · 10-22-2002, 06:15 PM

O-ya about the compression thing I have to take that out of my sig. I wanted to go N/A then switched to boost I went with dished JE pistons 8.5:1. My goal for the car is to have my Cobra run high 10's low 11's at the track and be semi streetable. I switch alot of parts on and off for race/street. Suspension shocks,springs,gears, Eric you brought up a good point If I want to dump the clutch at 5,500 with slicks I suppose the torque of the launch puts alot of extra stress on the blocks main caps and stuff. Do you think the R-block is streetable. I'm thinking of going with a blueprinted sportsman block from Keith Craft, DSS girdle and keep my boost to 9psi max. Maybe I can lighten the car for more speed!

andy669 · 10-22-2002, 09:55 PM

The Motorsport B50 block is a good happy medium. I think an R block is alttle overkill for what you want to do. A good friend of mine has a B block in his car and it is holding 18 pounds of boost and running 10.40's@132. An R block could take you near the 7's without any second guessing.

Andy

87lx58 · 10-23-2002, 01:39 PM

The R block uses same size cam bearings front to rear. most people that run R blocks use roller cam bearings. This means to run this block you need a special cam unless there is a new trick part out.. The Dart block is the better way to go if you spend that kind of money for street use because you can use factory style cams and it is just as strong. The A-4 block which is about like an R block will allow the use of factory cams if you can find one. The B-50 block is rated at 600 horse by motorsport. I would use the B block with a girdle. You have to ask yourself how many times are you going to ask your engine to sustain max power and keep it their. I have run into the same problem before when spraying nitrous. I see people all the time having $7000 in mods to a motor running a $200 block and worried about what to do. Get a good block or don't by the blower.

93 Cobra needs input · 10-23-2002, 05:29 PM

Boy the people at this message board sure have a lot of good mustang information to share. I'm glad I found Mustang Works. I think I'll try the B50 sportsman block with a DSS main girdle. If I get a good machine job done and keep my boost reasonable I think it will hold up, at least a little better than the factory 302 in my cobra. At least if the new motor blows I'll still have the factory cobra motor to put back in and it would give me a good excuse to build a big stroker out of a 351W block

Thanks

10-21-2002, 07:52 PM	#1
93 Cobra needs input Registered Member Join Date: Oct 2001 Location: Madelia,MN USA Posts: 58	Need help deciding on an engine block!! Finally getting the stroker together this fall and I have ran into some block and price problems what do you guys think? First option, factory block machined locally with stud girdle, although cheap I fear the worst with a supercharger and high dollar rotating assemble. I wanna start at 9psi maybe a little more in the future. Second option Keith Craft will send me a new 302 blueprinted and bored with torque plates line honed and clearenced with arp main studs installed for around $750 I talked to them about a sportsman block thinking it sounds like a happy medium and they said the block is basically the factory 302 with a little better main caps and that I should go with the R302 block to have absolute no worries with boost and HP The problem is they want $2450 out the door for an R block ready to install with all the fancy machine work done. I'm leaning towards the new stock block with good machining. I know the block it the foundation for all the other parts but I think that R-block is a little steep. Can someone here convince me to go with the R block I don't have tons of money but I really want my car to have a ton of HP and not have a lot of worries about throwing a rod or breaking a main cap. Sorry this got so long! __________________ 331 stroker, JE 8.5:1 pistons, H-beam rods, steel crank, main cap, msd with 3step, BBK ceramic long tubes,TKO, 4.30's, motorsport Z303, Victor Jr aluminum heads, crane gold 1.6, southside lift bars, 90/10 front, 50/50 rear, centerforce dual friction clutch, Vortech S-trim soon.

10-22-2002, 08:38 AM	#2
302 LX Eric or '331 LX Eric' Join Date: Jan 1999 Location: Columbus, Ohio Posts: 2,142	My quick analysis and opinions... 1) Are you running 10:1 compression? If so, watch out throwing 9psi or even more at it... 2) A well built/machined stock 302 block with T6 6061 Girdle (like what DSS sells) with all ARP, etc. should hold up fine to 500 HP, maybe even 550 HP. Over that and you're pushing the envelope. Also, are you going to be dropping the clutch at 5500 with slicks out back and a drag suspension? If so, then look into the R-Block, over than that you should be fine. 3) DART also has some new blocks out there, but I think they require high dollar machining as well - but not sure. Just another option to consider. 4) Lastly, (and maybe this should have came first) what do you want out of the car in the end? That is the ultimate question that will determine whether you need to plunk down the big $ for the R-block or stick with the trusty stocker. E __________________ 1991 5.0 LX Coupe - 40,750 miles 331 cu. in. / Tremec 3550 / BFG Drag Radials 12.22 @ 114.31 mph - w/1.89 60'

10-22-2002, 11:27 AM	#3
LX XLR8R Dirk Diggler Join Date: Feb 1999 Location: SLOATSBURG, NY Posts: 1,931	my opinon..grab a 351 from dss..my 408 with girdle,custom pistons, steel crank and steel h-rods and ARP'ed out will support 750hp..thats a happy median to me..total bottend end cost with low compression pistons is $3500 __________________ 95 undecided cubes, AFR 185s,undecided cam, undecided intake, and a 150 hit 89 "turbonotch" 2.3T You might want to hold on..i saw this on a cartoon once

10-22-2002, 06:15 PM	#4
93 Cobra needs input Registered Member Join Date: Oct 2001 Location: Madelia,MN USA Posts: 58	O-ya about the compression thing I have to take that out of my sig. I wanted to go N/A then switched to boost I went with dished JE pistons 8.5:1. My goal for the car is to have my Cobra run high 10's low 11's at the track and be semi streetable. I switch alot of parts on and off for race/street. Suspension shocks,springs,gears, Eric you brought up a good point If I want to dump the clutch at 5,500 with slicks I suppose the torque of the launch puts alot of extra stress on the blocks main caps and stuff. Do you think the R-block is streetable. I'm thinking of going with a blueprinted sportsman block from Keith Craft, DSS girdle and keep my boost to 9psi max. Maybe I can lighten the car for more speed! __________________ 331 stroker, JE 8.5:1 pistons, H-beam rods, steel crank, main cap, msd with 3step, BBK ceramic long tubes,TKO, 4.30's, motorsport Z303, Victor Jr aluminum heads, crane gold 1.6, southside lift bars, 90/10 front, 50/50 rear, centerforce dual friction clutch, Vortech S-trim soon.

10-22-2002, 09:55 PM	#5
andy669 Registered Member Join Date: Jan 2001 Location: Moline Il Posts: 901	The Motorsport B50 block is a good happy medium. I think an R block is alttle overkill for what you want to do. A good friend of mine has a B block in his car and it is holding 18 pounds of boost and running 10.40's@132. An R block could take you near the 7's without any second guessing. Andy __________________ 88 coupe 91 LX NMRA Pure Street 5120

10-23-2002, 01:39 PM	#6
87lx58 Registered Member Join Date: Sep 2002 Location: pace.fl Posts: 5	The R block uses same size cam bearings front to rear. most people that run R blocks use roller cam bearings. This means to run this block you need a special cam unless there is a new trick part out.. The Dart block is the better way to go if you spend that kind of money for street use because you can use factory style cams and it is just as strong. The A-4 block which is about like an R block will allow the use of factory cams if you can find one. The B-50 block is rated at 600 horse by motorsport. I would use the B block with a girdle. You have to ask yourself how many times are you going to ask your engine to sustain max power and keep it their. I have run into the same problem before when spraying nitrous. I see people all the time having $7000 in mods to a motor running a $200 block and worried about what to do. Get a good block or don't by the blower.

10-23-2002, 05:29 PM	#7
93 Cobra needs input Registered Member Join Date: Oct 2001 Location: Madelia,MN USA Posts: 58	Boy the people at this message board sure have a lot of good mustang information to share. I'm glad I found Mustang Works. I think I'll try the B50 sportsman block with a DSS main girdle. If I get a good machine job done and keep my boost reasonable I think it will hold up, at least a little better than the factory 302 in my cobra. At least if the new motor blows I'll still have the factory cobra motor to put back in and it would give me a good excuse to build a big stroker out of a 351W block Thanks __________________ 331 stroker, JE 8.5:1 pistons, H-beam rods, steel crank, main cap, msd with 3step, BBK ceramic long tubes,TKO, 4.30's, motorsport Z303, Victor Jr aluminum heads, crane gold 1.6, southside lift bars, 90/10 front, 50/50 rear, centerforce dual friction clutch, Vortech S-trim soon.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Rare Mustangs....Got One?	1969Mach1	Blue Oval Lounge	22	09-25-2010 04:59 AM
Engine Block Casting #s	CHRIS75	Windsor Power	24	05-31-2004 04:03 PM
Engine Block	schizcat	Windsor Power	3	11-09-2003 12:38 AM
5.0 Engine Block thoughts	squid	Windsor Power	7	12-03-2002 08:05 AM
Will the 5.0 become obsolete	vetteeatr	Blue Oval Lounge	36	07-11-2002 08:39 PM