cutlassefi

You're right. I said it wasn't. But like you said you're stuck with it so I guess it doesn't matter.

coppercutlass

So what you are saying is you are arguing for the sake of arguing ? Im having dejavu. I kinda skimmed through the back and forth so from what I gathered it took a few post for everyone to agree he has what he has.

rcktdoc

I NEVER said I was STUCK with it. I built a small CUIN olds engine and went faster than any one else with 400 cuin naturally asperated full body 3400 lb 10" tired car. We went just as fast and in somecases faster than guys with 480 plus inch big blocks running cars within the same perameters. Besides that I was refering to the 350 in this thread.

Greg

captjim

No, what Mark and I are both saying is that yes, CutlassFreak has this big-domed short block and is using what he has, but in both of our opinions, there are better ways to achieve a high compression, high horsepower engine without the inherint issues that come with those big domes.

coppercutlass

OK I want to see you and mr efi's big hp combo's greg has done it with domed pistons so where are yours ? This comes down to theory vs. actual experience . You can think there is a better way and there probably is but have you built an engine of that caliber ? It's like the seasoned mechanic vs the out of school tech the tech knows theory but the seasoned tech knows experience. Im not saying I will ever build an engine like greg's or even like mr freaks but to each his own.

rcktdoc

Who cares the point is moot he has what he has and he wants to use what he has.

Greg

67 Cutlass Freak

To Mark and everyone else - If you were in my shoes, and wanted to finish this engine without spending too much more money, what recommendations would you have. If I was able to go back in time, I would have done things a little different. First I would have built a stroker with Chevy rods and flat tops. The young man that I was helping build this engine, picked the pistons with our machinist's help. The short block is assembled. The cam has been degreed in. I realize that it may have to come back apart for clearencing. I really like Smitty's way of calculating the dome. I will do that. This engine kind of fell into my lap. Yeah I paid for it, but I never wanted it. I don't have a use for it. We're getting a little off the subject here of "Home porting Techniques" but it's probably OK to touch on some of this, so that guys will know what's involved with trying to fit a size 12 foot into a size 10 shoe. Maybe I should have started a different thread, but I didn't realize how adamant you guys would be over these Mt Rushmore pistons.

captjim

This is the second time recently that you jumped into a discussion for no other reason than to be argumentative, adding nothing to the thread.

captjim

I have just seen catastrophic failures with pistons hitting valves with these big domes. I see no real solution, other than removing and selling them, which might not be a viable option. Otherwise, put BBO heads on it and make it a fun street engine??

rcktdoc

Thats probably because the guy that built it didnt know what the hell he was doing.

Greg

cutlassefi

For the record, one last time. If you're looking for that high of a compression ratio, then as has been mentioned already a dozen times, you're most likely stuck with what you have. Make the best of it, plain and simple.

For the rest, please don't put words in my mouth. I'm pretty sure that if a big dome was the ticket for the best power, apples to apples, then I'd be willing to bet all the best engine builders in the world would do them that way. The fact is they don't, not unless they HAVE to, based on available heads, pistons and desired compression ratios.
Of all the most popular, highest output engines designed from a clean sheet of paper in the last 10 years, how many have this configuration? Hmmmm....check it out for yourself.

Done here.

coppercutlass

Jim I jumped in because you guys are at it again . I want to see what you have done first hand in that range of power that make your opinion come from actual first hand experience. Im questioning you not starting anything.

67 Cutlass Freak

dontthrowpoop.png


My mother taught me at a very young age if you don't have something nice to say don't say anything at all.

rcktdoc

Good go away and worry about building your own crap.

Greg

67 Cutlass Freak

OK guys I think we can all agree that we love Oldsmobiles. There's different thoughts and opinions on how to make them go fast or last. Let's please stop bickering. I know you guys feel strongly about your own accomplishments. I think that everyone here is truly wanting to help. Noboby on this board wants to see another Olds engine fail (Except maybe Nick). You know I'm just kidding. I love you guys. Seriously though I'm very interested in what specific clearances I should be shooting for. Valve to piston, piston to head minimums. Do you guys think we should have gone bigger on the cam? Don't fault Mark at all for that. When he helped me choose the cam we had no idea what kind of car this thing was going in. Still don't know for sure so we were guesing heavy G body with a tubo 350 and 390ish gears. Jim by the way the heads I'm going to use are ported GA's. Everybody lets try to work together to keep this thread informative and not clutter it up with BS. Please post information that you think the entire Olds community would benefit from viewing. I really don't want Oldcutlass to have to come in here and start deleting posts again. I'm sure he's getting tired of that.

380 Racer

Ahhhh so that's who you are Greg, no wonder about not knowing crap. Why don't you tell them the whole story. Your vast knowledge, 9000 rpms did not pan out with piston/head clearance. Never lasted long did it?

rcktdoc

Nick GO F*** yourself you dont know what your talking about. You are the lieingest MFR I have ever known.

Greg

Smitty275

Piston to head .040 minimum for a stock steel rod engine. Piston to valve .100 min on exhaust and .080 on the intake. Your much more likely to smack an exhaust valve, especially if your bouncing it off the seat/floating it.

380 Racer

Haven't changed have you? Name calling is what you do best .

rcktdoc

Just ignore the old fool behind the curtain....... Are we in IOWA yet Toto?

Smitty275

Well I must say I'm glad to see Greg/rcktdoc back on a forum. He has a lot of good back ground and is a good guy. Hell of a body/paint guy and knows the intricacies of the Oldsmobile a bodies very well. Greg was the ORIGINAL Olds wheel stand champ.

Sorry I can't say the same for Nick/380 racer.

rcktdoc

Thanks Mark,We werent realy the champs but we did give them something to think about.

Greg

73aussie455

I've been following this thread from the start, very informative and a bit entertaining too..
There is a wealth of info here for backyard guys like me that just wanna do a bit of cleaning up so we can get that " I ported my own heads " warm fuzzy feeling when we drive our rides down the street, without going the whole max cfm flow racing job. Thanks guys.

I have a pair of '73 J heads off the car atm and a pair of '68 red 455 C heads sitting in the shed. also have the option on a pair of 425 B heads. Both B& C heads have 2.0" inlet valves.
Before I get out the dremmel, which heads would be the best to put back on. I'm confident to do a bit of cleaning up after watching this thread-nothing ott like you guys tho.

I'm thinking of a cam-a bit better than the smog one currently in there, pistons to raise the cr to about 9:1, a performer ally manifold and dual or large single exhaust. I'm keeping the Q-jet 800cfm 4v she came out with.
Just swapped the open rear out with a posi 3:23 center. Only a Saturday night street cruiser.

What would be the minimum port work I could get away with on one of the above heads?
Thanks again guys.

J-(Chicago)

The best answer that I have for you is......The ones with the best valve guides.

67 Cutlass Freak

J(Chicago) nailed it there. I would not consider doing the J's myself. The B's & C's started life with almost the same port size. I would start with the set of C's myself. The set of B's might become more valuable down the road because fewer were made. Take them to the machine shop to have them cleaned and inspected for cracks. The guides or seats are pretty expensive to replace. For example the set of #5 heads I'm doing are having bronze guides installed. Parts and labor is $270. You should tell your machinist what your intentions are. When you're all done porting you will want to spring for a good quality 3 angle valve job. If you've been following along, then you know the biggest gains come from pocket porting and a good quality valve job. By pocket porting we are refering to the bowl work. Your machinist may be able to help you out by using a bowl hog to get you started, and rough in a cut. This will save a lot of time. Other than bowl work you might want to get rid of the bumps in the intake and exhaust ports, but you probably don't need to go any further than that. I would not recomend a dremel tool. If you don't have access to a compressor and an air dye grinder, you might want to pick up something like this-
http://www.ebay.com/itm/380867230247...84.m1423.l2661

73aussie455

Thanks for that guys.
Yeah I'd figured on a 3 angle valve grind. I have an electric cable drive grinder as well with a lot more grunt behind it, I'll use that instead of the dremmel. i have access to an engineering shop so I'll make a nuisance of myself there.
cheers.

67 Cutlass Freak

I have a cable drive also, but it didn't work out so well. Not enough RPM and the cable limits free movement and control. Didn't work too well for me. The Dewalt that I posted a link to is kind of bulky, but if you don't have a compressor it's a good option.

380 Racer

rotflmao

J-(Chicago)

The Dremel tool will work for you in the bowls if you use cut off wheels and keep it moving. It will definitely take longer than a big ol' carbide burr, but you can get it done.

Don't bother putting those wimpy 1/8" cutters or stones in them though. You'll find out fast that they're a total waste of time.

rootney

I used a Right Angle die grinder with carbide bits to remove bulk metal.
Switching to a dremel with flex extension for finer work.
The RA grinder and flex shaft allow almost all the work to be done from a stool instead of standing. Big help with fatigue. You can go longer with more consistent quality.

George

Smitty275

A Dremmel, really. You guys are kidding right. There is no way on God's green earth I would even consider it. At least go to Harbour Freight and buy a cheap die grinder and couple of carbide burrs. Will save you thousands of hours.

73aussie455

just spoke to my mate with the workshop he laughed too, he said help yourself to the air grinders and burrs.

rootney

I agree.
I said the DG and carbide burrs for the heavy work and used the dremmel for the clean up.
The dremmel also was good for the combustion chambers, where I didn't want to remove too much.

67 Cutlass Freak

I've never tried a Dremel tool for porting. Those bits are very small, and it only has a 1/16" shank. I'm with Smitty on this one. I know Joe Mondello used to do a lot of porting with the electic type of grinder that I posted a link to. I don't own one but they look pretty big and bulky to me.
I was messing around with the GA heads that I ported. Did a trial fit on some valves. The intakes are 2.12" and the exhaust are 1.68" I may end up using 2.07" intakes, but this fit pretty good and there's .035" gap between them. Now I really have to dig out the 350 and check the valve reliefs.

119-1975_IMG.jpg

Smitty275

Use the 2.120/1.680 set up. Enlarge the intake throat accordingly.

coppercutlass

You can buy one of them grinders dave posted from harbor freight tools. Buy the warranty and it gets replaced for free no questions asked for 2 years.

Lars

don't buy the carbides at HF they suck, buy a $20 1/4 bull nose carbide, I got mine from Fastenal, I got a newer one barley used, ill ship it to ya 18 tyd

coppercutlass

Anyone wanna buy a snap on carbide set for 120 ? Never used. Also I was talking about the grinder from hbt. Not the carbides lol. I would not trust any bits from them .

67 Cutlass Freak

In the beginning of this thread I started off by discussing comfort and safety. I own a set of post type cylinder head holders. I'll be damned if I can find them. I haven't seen them for years. So yesterday I spent about 1/2 hour during my lunch break to make this head holder from some scrap steel. If anyone wants the dimensions, I will be glad to post them. I used some heater hose to protect the head. It works excellent. I used it all day today.
CIMG4531.jpg

67 Cutlass Freak

Today I spent some time going over the port work on my GA heads. If you've been following along then you know the story on these heads. I pushed the width out as far as I could on the intake ports. I was getting nervous with how close to the push rod holes I went. I didn't punch through anywhere. I also did a rough cut out to 2.07" valve size and opened up the bowl a bit more. I will probably end up going with the 2.125" valves, but I need to dig out the SB engine these are going on to, and make sure the valve reliefs are large enough. Here's some photos-
CIMG4535.jpg
CIMG4537.jpg
CIMG4538.jpg
CIMG4534.jpg
J(Chicago)'s heads are at the machine shop having the guides installed. When I get them back we will do the valve job. In the meantime I'm going to finish the port work and valve job on these GA's then we're off to the flow bench. I will post all our results here, good or bad. I am hoping for the best. I'm sure there will be some inconsistency across the ports on each head. I will most likely try to equalize the flow numbers, but I don't know if they will make it back to the bench for a second time to verify my work. The bench time costs money, and everyone involved with these heads is on a tight budget. Including myself.