I6 vs V8 - Page 2 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

PanelDeland · 06-02-2007, 08:35 AM

If you're going to swap tranny's I would suggest you go with an AOD maybe a 700R4 or 200R4.You may as well get the advantage of the overdrive if you are going to the trouble.I think the 200R4 would do fine with the HP a 6 puts out but it may be a bit weak for the Torque.

**slomotion** · 06-02-2007, 10:53 AM

I think I'd go for the 292. You can't get the rpm up like a 350, but the torque is a fair trade-off. Headers, Offy intake, 390cfm Holley, and an HEI GM dizzy.

Even if you kept the engine bone stock you'd be amazed at what a T5 5 spd will do for the driveability!

**'68OrangeSunshine** · 06-02-2007, 08:26 PM

RUB1401-- What is your rear-end ratio? 1/2 or 3/4 ton? Wheelbase? Stance: stock, lifted or notched? Tire/wheel diameter? You can't find a more bulletproof tranny than the SM465, and since you already got one you don't need to spend dough on another trans. But that's my opinion. I have a buddy who has a T-5 in his '88 S/10. I think they're lemons, like the 700R4s. We've had it in-and-out 3 or 4 times in as many years. I don't trust a manual that uses ATF slushbox juice. But that's just my opinion.
I'm running a rebuilt 292 L6: bored.030-over, 1.84 intake valves, Rhoads lifters, Badger pistons, 260H Crane cam. Edelbrock 1404 500 CFM 4 barrel on an Offy intake over Clifford headers. SM465 4-speed, single unit propshaft, 3.73:1 12-bolt Corp rear end w/Eaton posi. Tires are 235/85/R16 Dunlops. Truck is a '68 stepside, short wheelbase, factory [raked] stance. Tall, skinny tires, I find, make a big difference on an L6-powered truck. I've tried the wider, fatter, lower tires that run good on 4x4s w/V8s, and find you have to over-rev the L6 just to keep up. Since these L22-series sixes were designed as work truck powerplants, they typically run at a lower RPM than a V8, but with much greater torque and fantastic reliability/longevity.
Slomotion-- Very nice set-up. How do you like the Langdon cast headers? I envy your cast-aluminum valve and lifter covers, nice look. Just one question -- why does your thermostat housing go to the right instead of left? Non-stock radiator?

**slomotion** · 06-03-2007, 01:10 PM

68Orange, I like the headers, they torqued up fine the first time and haven't leaked since. The pic was more or less a mock-up, you're right, the therm housing goes to the left. The rocker cover came from Jegs, and the side covers, headers, and T5 came from Langdon. He took a "World Class"T5 housing from a Camaro, put Mustang gears in it, and a Sonoma tail shaft to put the shifter in the correct position. What happened to your friends T5? I'm curious because mine goes great.

Sorry Rub1401, didn't mean to hi-jack the thread......

retodd7711 · 06-03-2007, 04:04 PM

Oh the drama!! 6 or 8 ?? Last week at our cruise in there were 5 67-72 trucks. Mine was the only 6 banger. How cool is that.

06-02-2007, 08:35 AM	#26
PanelDeland I am a Referee of life. Join Date: Jun 2000 Location: Greensboro N.C. Posts: 13,993	Re: I6 vs V8 If you're going to swap tranny's I would suggest you go with an AOD maybe a 700R4 or 200R4.You may as well get the advantage of the overdrive if you are going to the trouble.I think the 200R4 would do fine with the HP a 6 puts out but it may be a bit weak for the Torque. __________________ The 47-present Chevrolet and GMC Truck Message Board Network,it's owners,moderators,members,and associates of any type should not be held responsible for my opinion. You can't fix stupid,not even with duct tape. "My appearance is due to the fact that "GOD" does punish you for having too much fun!" Barrett-Jackson has perfected alchemy,they make rust into gold! "You can lead a horse to water but you can't saddle a duck" "Cleverly disguised as a 'Responsible Adult' "Sometimes your Knight in shining armor is just a retard in tinfoil"

06-02-2007, 10:53 AM	#27
slomotion Old Duffer Join Date: Mar 2003 Location: Maine Posts: 1,821	Re: I6 vs V8 I think I'd go for the 292. You can't get the rpm up like a 350, but the torque is a fair trade-off. Headers, Offy intake, 390cfm Holley, and an HEI GM dizzy. Even if you kept the engine bone stock you'd be amazed at what a T5 5 spd will do for the driveability! Attached Images __________________ '68 Short C20 Flatbed Dually w/ 292 4bbl, Langdon cast headers, and WC T5 trans. '81 G10 Shorty Van "Good judgement comes from experience, and a lot of that comes from bad judgement." Will Rogers "Under promise, then over achieve."

06-02-2007, 08:26 PM	#28
'68OrangeSunshine Senior Member Join Date: Feb 2002 Location: Tucson, AZ USA Posts: 7,283	Re: I6 vs V8 RUB1401-- What is your rear-end ratio? 1/2 or 3/4 ton? Wheelbase? Stance: stock, lifted or notched? Tire/wheel diameter? You can't find a more bulletproof tranny than the SM465, and since you already got one you don't need to spend dough on another trans. But that's my opinion. I have a buddy who has a T-5 in his '88 S/10. I think they're lemons, like the 700R4s. We've had it in-and-out 3 or 4 times in as many years. I don't trust a manual that uses ATF slushbox juice. But that's just my opinion. I'm running a rebuilt 292 L6: bored.030-over, 1.84 intake valves, Rhoads lifters, Badger pistons, 260H Crane cam. Edelbrock 1404 500 CFM 4 barrel on an Offy intake over Clifford headers. SM465 4-speed, single unit propshaft, 3.73:1 12-bolt Corp rear end w/Eaton posi. Tires are 235/85/R16 Dunlops. Truck is a '68 stepside, short wheelbase, factory [raked] stance. Tall, skinny tires, I find, make a big difference on an L6-powered truck. I've tried the wider, fatter, lower tires that run good on 4x4s w/V8s, and find you have to over-rev the L6 just to keep up. Since these L22-series sixes were designed as work truck powerplants, they typically run at a lower RPM than a V8, but with much greater torque and fantastic reliability/longevity. Slomotion-- Very nice set-up. How do you like the Langdon cast headers? I envy your cast-aluminum valve and lifter covers, nice look. Just one question -- why does your thermostat housing go to the right instead of left? Non-stock radiator? __________________ Every 25 years I like to rebuild that 292, whether it needs it or not.

06-03-2007, 01:10 PM	#29
slomotion Old Duffer Join Date: Mar 2003 Location: Maine Posts: 1,821	Re: I6 vs V8 68Orange, I like the headers, they torqued up fine the first time and haven't leaked since. The pic was more or less a mock-up, you're right, the therm housing goes to the left. The rocker cover came from Jegs, and the side covers, headers, and T5 came from Langdon. He took a "World Class"T5 housing from a Camaro, put Mustang gears in it, and a Sonoma tail shaft to put the shifter in the correct position. What happened to your friends T5? I'm curious because mine goes great. Sorry Rub1401, didn't mean to hi-jack the thread...... __________________ '68 Short C20 Flatbed Dually w/ 292 4bbl, Langdon cast headers, and WC T5 trans. '81 G10 Shorty Van "Good judgement comes from experience, and a lot of that comes from bad judgement." Will Rogers "Under promise, then over achieve." Last edited by slomotion; 06-03-2007 at 01:10 PM.

06-03-2007, 04:04 PM	#30
retodd7711 chrome makes it go FASTER! Join Date: Feb 2007 Location: Cleveland Tennessee Posts: 2,884	Re: I6 vs V8 Oh the drama!! 6 or 8 ?? Last week at our cruise in there were 5 67-72 trucks. Mine was the only 6 banger. How cool is that. __________________ She can't cook and she won't clean. But she looks good in a skirt and she brings me beer. She can stay for now. EDIT:: But she left me anyway, So forget her. 1962 GMC Stepside V6 4 speed My rolling resto thread http://67-72chevytrucks.com/vboard/s...d.php?t=324226 My old farm truck http://67-72chevytrucks.com/vboard/s...=1#post3465005



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.