GEARMAN69

I picked up a good running freshly built 70 350 but after pulling off mismatched heads a 6 and a 3A , I see the expected and dreaded Speed Pro 332AP30 pistons . It is tempting to use it with just some different heads and maybe a small cam but the compression ratio is still as low as 7.9:1 even with the #6 heads based on uncut block deck and minimal surfacing on heads if that sounds right. I could runs some #4 330 heads. Would that be about 8.2:1-8.4:1 actual ? If so milling to 60 cc would bring it cost to 8.9-9.0:1 ? Thoughts

80 Rocket

With pistons .055 in the hole (short on compression height), 24cc dished pistons, and 59cc heads, I come up with 8.2:1. No way to get 9:1 with those pistons unless you mill the block deck.

GEARMAN69

Dang, your saying at 59 cc it would only be 8.2 ! Or did you mean 69cc ? Wow that disappoints.. What a dog with stock heads and cam too and a 3A head 6 head combo... haha

80 Rocket

Yup, 59cc heads. That will be a .060"+ mill job to get there. Then you will be spending money getting the intake milled to match the heads. It costs a lot of money in machine work to use those pistons if you are trying to do a performance type build.

GEARMAN69

Well that pretty well keeps me from wanting to use it. I was hoping for some value as is on block but Damn I can't go there . Got to have some power.

80 Rocket

Good answer. Between the heads, intake, and block.......you might rack up over $400-$500+ in milling. All that to use a cheap, stock replacement piston with a deep dish (not good for combustion characteristics).

For a little bit more, you can get the forged speed pros, and balance the assembly. But there are much better options out there than the speed pros. Before you know it, you get better pistons. Then, you get some good rods. Might as well get the heads nicely ported. Since you have gone that far, a roller cam will definitely give it some more pep. All of the sudden you wake up penniless, but with a huge smile on your face because you have a bad *** small block Olds. You can thank me later.

GEARMAN69

Thanks yeah. Easier just to do the block prep and 're ring STD 6 cc pistons in my wagons 98k mile 310 hp 350 that had a rod bearing knock. Turn the crank may be just rings and bearings. Or 're ring the 403 STD engine I picked up and use the #6 heads on it. Could use the crank out of this 70 350 maybe. Save the fresh bore for some forged 030 better slugs.

GEARMAN69

I am not going to spend any real $ on this block as it is but I do want it to run and be a viable 87 octane mule of sorts. My buddy is bringing over some virgin 67 #4 heads and four barrel intake I am going to clean up just cost of head gaskets and stuff to make it ready to go. An option down the road would this same engine could get 030 W31 flat tops swapped in with a balance and the #4 get big valves and porting at that time with a cam swap for a little race engine ? Bottom line is if I do not put the Rallye engine in my wagon it will keep the fire on my butt to get the rallye going that much faster and I will make use of a free fresh rebuilt 87 octane AC equipped setup to get easy road time now on the wagon .. Still have a 403 I can build up for the wagon next year and or the original 310 hp 350

80 Rocket

I hear ya. I threw together an engine (350 sbo) with parts laying around my shop to race in street class this year (12.00 and slower class bracket race). It features a completely stock bottom end with 6cc factory pistons. The block was in great shape, put some new rings and bearings in it as well. Should be right around 10:1 compression.

I did up a set of #7 heads with 2.07/1.71 valves. CutlassFreak on here did some porting to them a few years ago but were never ran. I did a little more porting myself, but nothing extreme, just wanted a better transition with the bigger valves I installed. Funny thing was they flowed slightly less than a set of #7s I did about 6 months ago. The #7s I did before only had 2.00" valves and these have 2.07" valves.

I am doing some modifications to the Holley Street Dominator intake on the mill as it needs some help in the plenum. I also milled off the EGR and heat choke platforms so you could say it is kind of an air gap now. Haha! The carb pad has been milled about .500" and I am going to add an aluminum spacer which will allow me to transition the spacer into the plenum much better.

I also got a free used cam and lifters from CutlassFreak. It is the JM-25-28 cam 236/248 @ .050 with .523/.544 lift.

When its all said and done, I hope to be into the 11s on pump gas in my 80 Cutlass. Since street class is 12.00 and slower ET break, I will add some weight to the car to slow down if necessary......although the hot summer air should slow it down for me.

GEARMAN69

Nice ! That's gonna scream. I like the thought of waay down the road if this extra post body sticks around and doing a high stall 8" converter 355 olds with 4.56 or 4.88 gears with bodya very gutted out light weight.

80 Rocket

That's my 80 Cutlass. Interior is gutted with roll bar added. 4.56 gear with a 30" radial slick. I am going to try a few different converters to see which one works better for consistency. I have an 8" and 10" that are setup to properly bolt in. The car weighs 3100 with me in it.

GEARMAN69

The turd motor is ready to go in my wagon as a mule. The #4 heads had previously been redone with hardened seats on all so just clean it up , lapped , and re sealed etc.. Sexy 250 flywheel HP here I go ! LOL I hope to get it in and fired up over this holiday weekend. Then I can finally get the original 310 hp #6 head 98k mile engine on the stand and some evaluation on it. Rebuild and swap #'s back 350 together original next year. For the record the engine was free essentially as were the heads and intake so just gaskets at Rockauto cost got this together.

GEARMAN69

Its alive , so far so .. good.. this was dry fired and open pipes 67 # 4 heads and 67 intake on 70 shortblock

GEARMAN69

Running better than expected honestly. Stock converter and 3.08 mini spooled rear big station wagon can bust loose the stocker 14" tires and spin them pretty good just flooring it not power braking it.