Oldwolf

I wonder if itīs vise to machine stock rods fore bronze bushings and full floating pins? Is that going to weaken the small end? Are there any other way to use full floating pins than with bronze bushings?

Run to Rund

People have tried running the pins on the steel of the rods after honing the rods, with limited success. The factory pressed pins are fine for street use and mild racing. Your pistons don't have provisions for pin retainers anyway, so you would have to get race pistons. At that point, you are better off bushing the rods to small block Chevy size, 0.927" and getting pistons set up for that pin size.

cutlassefi

Why not use the Olds pin if the pistons allow it? The only other way to use a floating pin in a steel rod without a bushing is to have it DLC coated, too expensive. Bush it if you want to. You can also use a Ford FE bushing, probably cheaper that an Olds. FE is .975, Olds is .980. No issue.

Run to Rund

Why bore out the rod just to bush it? You would have to do that with FE pins, BBC pins, etc. Also, the SBC has a plethora of good pistons available cheap, many set up for floating pins. With such a setup you can save 200-275g per piston/pin, get thinner rings with less tension and less flutter with rpm, get rid of the pin offset, get a better grade of aluminum and a stronger piston.

Oldwolf

OK,What I can read out of the conversation is that I can bush ah stock rod for olds pin diameter, without risk to weaken the small end. Then If I choose to, I can use the chevy bushing if I want more pistons to choose from.

Great answers, lots of options.

Run to Rund

"It depends. . ."
How far you bore out the rod; how heavy the piston and pin are; how much rpm you will take it to. . .
IMO, if your engine is moderate enough that you are happy with stock rods, the pressed pins are OK, unless you do other things too, like deck the block .055" or thereabouts and use the race Chevy pistons and pins. Even then you can probably get aftermarket rods as cheap as fuly reworked stock rods. You might have to settle for SBC rods, which are available in 6" and other lengths, so you might not have to deck the block. If so, get the crank ground to accept SBC rod bearings.

Oldwolf

I want to give more information to my question, iīm satisfied with the answer thats itīs okay to bush stock rods. I have reconditionend stock rods and iīm planning to rew the engine to 6500rpm if the the heads manage that. Im going to bye the lightest an the most religiable pistons avaigable , and I maybee bush the rods, if thats nessesary because of the pins that delivered in the deal.
thanks.

Rickman48

I don't know if you've a small or big block, but it's not advisable to rev any olds motor to that rpm without building-up the lower end!
Lighten the crank, use aluminium rods, roller cam, etc. and it might live, but you should have a pair of comparitive heads to flow well to that RPM, and I don't think even Edelbrocks are good for that high, unless ported!
You might try another forum, Real Olds Power, and check-out some of the builds there!!

cutlassefi

I totally disagree, small Block Olds will rev to 6500 with little or no problem with good parts and a flat tappet cam. And you don't need aluminum rods, they're really not for the street anyway, and if you use a Hyd Roller they're good to about 6200 or so and that's about it.
A flat tappet cammed, balanced SBO will live at 6500 if all the parts used make sense, plain and simple.

Alot of combinations available if you want to use off the shelf SBC parts.

keithnh

Putting together 2 GM 350's right now sbc and pontiac. My sbc set up for 302 and the stack is bought, L99 crank (baby LT-1 3.00 stroke, scat 6.0 sbc 4340 rod and Mahle 350 hyper pistons. 350P will stroke its crank at Ohio Crank to 3.875 have BME 500 6.635 rods SBC big end and BBC small end and want to use Mahle hyper 350 chev pistons at std. 4.00. Block will have to be bored .120 Have been told they can be bored that far, hoping for the best. The BME's will be the highlight of this combo ... to make them work I have to either bush them from .990 to .927 or ream the pistons to BBC pin. Trying to do this on a shoestring and am not a big believer in fancy-dan pistons. If the Mahle sbc's would take the larger pin I would do it. Rather bush the BME's but am not sure its a good idea. See you on a similar topic. Any input? The 302 is destined for my 84 Cutlass with a 4 or 5 spd. The poncho for my 76 Cutlass circle tracker maybe?

cutlassefi

Sorry but neither one of those combos will work very well.
The sbc;
6.00 rod + 350 piston (1.55 comp dist) and 3.00 in stroke (\2=1.5), that equals 9.05 or about .025 higher than even a new block.
Pontiac- 6.635 rod+1.937(half of the stroke) and a 350 Chevy piston(1.55) = 10.122 or about .125 less than the standard Pontiac deck height, you might want to rethink these combos.

Jmo

keithnh

Thank you for your opinion. I know what the deck heights are. Both engines will be setup for a zero deck. The sbc by piston adjusting. Its 100$ ... far below a set of custom pistons. The poncho by decking the block. I could have it stroked a little more to accomodate and may still but I like the 350 to (389CI) number. The 302(310 @ .060)) will most likely have Fast-burn heads and is an 89 roller cam block. Vortec 062 a second choice. This motor will be aftermarket tbi. The poncho will have a ported set of numbers matching d-ports (69 #46). It will be carb. It is a 69. Both will be approx 10.0/1 CR. The info I was hoping for was about making the BME work in the given situation. Im working the 2 motors together trying to get discounts where I can. Both cranks will be nitrided locally ... since Im changing stroke on the poncho I will be using a fluidampr.

cutlassefi

So you're going to pay someone to deck .125 off the Pontiac block? Why?

keithnh

Both these motors are experiments. Im trying different things. Ever seen "Junkyard Wars" ?? Its like that. I have a bunch of stuff on hand Id like to use up. Whats not on hand I have to be cost effective at buying. The 350P uses standard pontiac d-port heads which appear to me and others to shroud intake flow (with the 3.88 bore) on the cylinder wall side ... so I am going to try and mine the bores out .120 to 4.00 std to unshroud alittle and use a plentiful cheap strong piston. I have 2 sets of BME rods, the more pristine set of 6.66/2.1/.990 Im holding onto to see what the first ones do. Both sets went to BME in Nevada and were sent back with a green light. The 6.635/2.1/.990 BME will be a big feature of this 350P combo. Accomodating them is why the -.125 deck as I am low not high like the 302C. I believe the sbc stack and rod journal size will be plenty strong for the poncho app as well as lighter to rev better, lower cost, and giving me stroke adjustability. I have several more Poncho's to build, proof is in the pudding, I guess ... Once done im gonna thrash this baby and see
Motor is not apart yet, actual dimensions may go one way or the other. There is a little crank wiggle room at +.125 stroking, not much, ... it may trash the crank ... but I have a guy who will do his best at Ohio Crankshaft and has given me a reasonable price. Id just as soon stroke a factory crank as buy an import piece.
Im going to focus on flow with both motors and intend to try to port the poncho heads to match the flow of a factory vortec which will be a tall order. Not just throught the head but from intake through exhaust. Id like to send all 3 pieces to someone and have them flowed and corrected as an assembly but I dont think thats possible. If it is I probably cant afford it. Id like to dyno too and am hoping to garner enough curiosity to maybe get that "sponsored" by the shop(s) who help me. The 302 out of a 1st gen roller block 350 could be a timely retrofit with gas prices like they are for those people that cant afford a new vehicle or to drive their cherished Chebby pick-ups (like mine ) around anymore. The 350P may be my schizoid answer to those who say there is no performance potential with said motor. I may get more ponies in addition to better fuel economy with it than a traditional 400, better low-lift flow, lighter rotating assy possibly with the right cam choice. I may have an Elgin cam made from one of my blanks with their recommendations.
I could use a 327 std piston and will probably do so on the 350P although they may be harder to come by. You are right about questioning the decking amount. .125 does not get rave reviews from machine shops although they say it can be done ....it changes valve train geometry and requires angle correction milling. It will make machining costs unnecessarily high. 10.231-6.635-1.9375 = 1.6585. CH of 327 piston is 1.675 so I can piston adjust easily again with a 4.00 bore sbc piston. I wanted to try going both ways to see what the cost is each way if they were similiar. I guess thats not in the cards. I expect to have to refigure valve train geometry during these 2 motor completions and look forward to it actually on 2 differing motors as it will add to my knowledge and experience base.
Bushing the BME seems to be the way to go in my rod piston mismatch so I will be looking for a set of full-float 327 std pistons and the right place to do that. Ohio Crank maybe. Just talked to Bill Miller himself ( WOW .. thats customer service ).... he said can do .... they will bush the rods and pin fit, these babies will be dead nuts