jdana24

I'm embarking on the rebuild of my original numbers matching 350 engine for my 1968 Olds Cutlass S Convertible. My thought is that I want the engine to look stock on the outside, but beef up the internals so that it is closer to the Ram Rod specs for that year, and run on pump gas. Two differences will be that I will not be using the dual snorkel ram air, as I will be using the stock air cleaner, and I will be using headers (I will clean-up and keep the original exhaust manifolds in my garage, just so I have the original parts). The car will not be raced, but I want to increase the horsepower, have a nice lope and sound, and have good torque. I will want to use the stock intake manifold; #5 heads that are on the engine, 2.00 intake and 1.625 exhaust valves; Ram Rod cam with the 308° duration and .474 lift (with appropriate springs/lifters/retainers, etc. from same company I get the cam from); stock 7028250 carb; Pertronix III;

A few questions:
- Which pistons should I use?
- Do I need the larger harmonic balancer?
- Which rockers would be best? Roller or straight pivot?
- Should I use the stock oil pan, or go to a larger pan?
- Should I put in 3.42 or 3.91 gears (Currently 3.08)?
- Should I have the carb rebuilt using rods, jets, and power piston spring to make it close to W-31 specs?
- I will be putting in a new clutch...any recommendations?
- Which headers will fit without any modifications?
- Do I really need hardened seats?
- How much porting and polishing is necessary since it won't be raced?
- Do I have the exhaust port divider filled?
- Do I have the hear riser closed?
- Which oil pump do you recommend?

I want to make sure that all of the parts work well together, and that I am spending my money in the right places, so feel free to make any recommendations. I'm sure I've left a number of things out, so let me know what else I can provide, so that you can help me make the best of this build. Since this is the first time I have ever planned and had an engine built, I want to make sure I provide the shop that builds the engine with all of the right info, so I don't run into any mistakes that will cost me additional dollars. Thanks in advance.

captjim

The following is my opinion. Also, I would use a different (better) cam. Which pistons should I use?
Speed Pro or Probe, Cr with that cam needs to be around 10 to 1.
- Do I need the larger harmonic balancer?
No
- Which rockers would be best? Roller or straight pivot?
Stock are fine for that lift
- Should I use the stock oil pan, or go to a larger pan?
Stock is fine, also no need for a HV pump.
- Should I put in 3.42 or 3.91 gears (Currently 3.08)?
3.42s should be fine
- Should I have the carb rebuilt using rods, jets, and power piston spring to make it close to W-31 specs?
Every engine needs to be tuned.
- I will be putting in a new clutch...any recommendations?
No opinion.
- Which headers will fit without any modifications?
I have Sanderson Shorties, IMO a nice compromise. My understanding is the Hookers are the best cost effective headers.
- Do I really need hardened seats?
I would.
- How much porting and polishing is necessary since it won't be raced?
No polishing, a little bowl work and a quality valve job is a cost effective upgrade.
- Do I have the exhaust port divider filled?
Does it get cold in Seattle? Electric choke? Not sure you will see much on a driver, I vote no.
- Do I have the hear riser closed?
Again, cold weather driving?
- Which oil pump do you recommend?
Stock replacement Melling, get the pick-up welded after checking clearance (1/2" with gasket).

jdana24

Thanks captjim. To answer your question if it gets cold in Seattle, yes it does, but I only drive the car during the late spring to early fall when the weather is in the upper 60's to low 80's, and I only put about 200-300 miles a year on the car.

cutlassefi

X2 with most of what CaptJim says except;

I'd fill the heat risers
Weld the center divider
Both will provide better scavenging, free hp.


And yes there are better cams out there, let me know when you're ready.

gregvm

With that cam choice and a manual trans (I assumed that since you asked about a clutch) I'd lean towards a rear gear of 3.73 (if a M-20), or 3.91 (if a m-21). Course there goes the fuel mileage, but at 300 a year, who cares.
You don't get the stall advantage of an auto with the manual.

I've used Zoom clutches for 30 years....no problems

Hope this helps


Greg
(only 300 miles a YEAR......geez, get out and drive that thing more, that's what its there for)

jdana24

Thanks Greg. Yes it is a M-21.

Rickman48

Match porting the intake, intake bowl blending, and full porting on the exhaust can make a big difference on an Olds, especially with a good 5 angle valve job!
I used to figure $10 per horsepower, before this *ing economy, and I still think it's money well spent - street or strip!
Providing you can find someone that could do the work.
Should be good for 50 - 75 HP and seat-of the-pants feel!

coppercutlass

heads are one of the best investments you can make. Pricewise i spent 1400 on my heads thats a full valve job on really worn out heads with stainless valves 2.07 in. and 1.73 ex. and with roller tip rockers, studs, new pushrods , retainers, bowl work no porting. I used a reputable olds shop and those heads just woke up the engine big time. i did not weld up the divider or get the heat riser filled imo they give some hp but cost wise id rather invest that money else where

captjim

Better, yes, but not free unless he can do it himself. Again, depending on cost, not sure it is a cost effective upgrade in this application.

captjim

I disagree with a lot of this. Most experts agree match porting shows little gain, sometimes actually hurts.

Bowl blend, yes. Good valve job, yes.

Full porting, no. Costs a lot on iron heads, #5s flow enough for this application. Not a cost effective upgrade, IMHO. Remember, he is sticking with the stock intake, that will limit overall and high rpm performance.

cutlassefi

Great points Jim.

jdana24

Thanks everyone for the input. After reading the comments, I did some online research and found that what captjim mentioned was echoed by many others who talked about this. They mentioned that match porting showed little gains, and could hurt the performance. Most of what I read said to do a bowl blend, and have a good valve job. And to respond to one of the comments, I won't be doing any of the work myself, since I have never done this type of work, I don't want to experiment on this engine. Any other comments on a good clutch to go with the M21? Also, any other thoughts on headers that will fit without any modification? Also, any other thoughts/comments on the build that I should consider, that haven't already been addressed?

Lee_A

"The car will not be raced"

With that one statement, I see no need for most of the things you are planning.

Save the money and frustrations of headers (and welding up the center divider), and use the money to convert to a hydraulic roller cam.

Have hardened seats installed, along with springs to match the cam, and maybe clean the bowls up a little. With a hydraulic roller, you'll want some sort of adjustable valvetrain, so I'd go with some decent roller rockers.

You ONLY need steep gears if you are going to race. With the added low-end performance of a properly selected hydraulic roller, I'd leave the gear alone. Steeper gears will only help if you are going to run drag radials.

Lee

jdana24

I figured I would give an update as to the status of my rebuild. After talking with numerous shops in Washington, I selected Everett ATS to do the build of my engine. I removed the engine and dropped it off to the shop in early December. While the engine is out, I will take on the task of repainting and detailing out my engine compartment as best as I can. Here are a few pictures of the original numbers matching engine that I am having rebuilt. The engine was out of the car when I purchased the car four years ago, but as far as I know the engine has been out of the car for about 15 years. I've asked the engine builder to take pictures as they are going through the build, so I will post them as I get them. Thanks to many of you for answering all of my questions as I've begun this process, and especially to Mark (Cutlassefi) as I have worn out his Inbox and cellphone with questions which he has always graciously answered.

jdana24

The current engine that is in the car is a 1970 Rocket 350 which I just pulled so I can detail and prep the engine compartment for the new engine once it is done getting rebuilt. This was not easy to get out with the engine lift which I had from Harbor Freight. The boom arm was about a foot too short, so I had to lift it from the side of the car and move it up about a foot, and then reposition the hoist to the front to finish getting it out of the car. Luckily I had a friend who was able to lend a hand. I've degreased the compartment and pressure washed it, so now I can start removing parts and taping things off. The 1970 Rocket 350 which I just pulled will be for sale, so if there is anyone in the Greater Seattle area that is interested in purchasing it, let me know. I will post it in the For Sale forum shortly.

jdana24

I looked at some of the wiper motor detail from some of the other members, and it inspired me to clean mine up before I start to put the parts back into my car after detailing my engine compartment. Mine was quite a mess when I started, but I am pleased with how it turned out, and I didn't have to repaint any part of it.

tonycpe

Nice job so far. Your wife is gonna be pissed when she sees her towels, LOL

jdana24

Just thought I would give another update on the progress of my engine rebuild, compartment painting/detailing, and various other restoration projects I worked on while my engine was in the shop. The engine rebuild has been completed, broke in and tuned on the dyno, and is now being installed back in the car with American Racing Headers. Also, putting in a new clutch, rebuilt power steering box, new 2 1/2 stainless exhaust pipes all the way back with new mufflers, and new shocks. In addition, I'm switching from 3.08 to 3.42 gears, and we're trying to track these down since Richmond was recently bought out and isn't making new gears until May 2013, so hopefully we'll find some by early next week. After all this work is completed, the car goes directly to the paint shop to bring it back to its original Ivory color. Listed below is a link to photos of the project.

https://plus.google.com/photos/11632...71310642591938

In the upper right corner of each photo is a brief description.

captjim

Care to share the build specs and dyno results?

cutlassefi

Hey Jeff,

Thanks for the update.

Once you post your build and dyno info you'll want to compare it to this;
http://72.22.90.30/phpBB2/viewtopic.php?t=85849

I think you did o.k.

jdana24

Once I get the car back, I will have all of the exact documentation on the build, and will also scan and post the dyno results. It went on the dyno twice, but I was only there on the second day, and it had a 348.6 HP and 378 TQ. My game plan on this build was to keep it stock looking on the outside, but beef up the internals. The only place it will not look stock is that I am going to be using the American Racing Headers, however these were not on the engine when it was dyno'd since they didn't fit his setup, so I had to use an old worn out set of headers that left a lot to be desired. The car has an M-21 4 speed, and I will be switching from 3.08 to 3.42 gears, and the car has power brakes. I'm using the stock iron intake, but am jetting the 7028250 Q-jet to W-31 specs. I'm keeping the #5 heads and going with 2.000/1.625 valves, and had a 5 angle grind with light bowl work done, and went with Dave's HEI ignition. I went with a full roller setup, and Mark (cutlassefi) ground the cam for me, which I will scan and post the specs. Filled the heat riser, and welded the center divider. I'll get the compression figures, but it ended up close to 10:1. More exact updates will come shortly, along with a video I took from the day I was at the second dyno.

cutlassefi

Well done Jeff. You made just 36 hp less and 32 less lb/ft of torque than the latest HP TV build, very respectable. They had a similar cam but Edelbrock heads, RPM intake, 800 cfm carb and about the same compression.

Nice job, how did it sound?

jdana24

Thanks Mark. I'll post a video of it on the dyno, once I can edit it down to a reasonable length. I don't think anyone wants to hear 30 minutes of this engine on the dyno. The audio isn't very good, and with the exhaust fans blowing it was real loud in the room. Also, the old headers were lousy and went straight into the trash after the dyno. I wish I would have bought a cheap set from Summit and had them cut-up to fit the dyno as opposed to buying a used set, sight unseen, which ended up almost useless. With all that being said, I think it will sound real nice with the new American Racing Headers, new stainless pipe all the way back, and new mufflers. Once all of this is installed, I will shoot another video, and post it. I'll try to get the dyno video up tonight or tomorrow.

jdana24

OK, Mark, and to anyone else who wants to see it, here is the day two dyno video. As mentioned before, it is rough, but all I had was a Flip Mino camera. Sorry for the delay, but had to convert from a .avi to a .mov to make it compatible form iMovie. I'll post the dyno sheets as soon as I get them from the engine builder. Hopefully in the next week or so. Once again, there was a delay, since tracking down the Richmond 3.42 gears was quite the adventure. But finally on Monday, I was able to find from Just Differentials what must be the last set in America, and I had them overnighted to my shop for installation. Hopefully this will be the last hurdle. Below is the link to the video, which may be a little boring, but it's all I have at this point (Just click on the engine photo and it will play the video):

https://plus.google.com/photos/11632...21167123677329

RetroRanger

jeff
thanks for posting your engine details looks like it gonna be nice when you get it all back together good luck

jdana24

And just an FYI, just click on the engine photo and it will play the dyno video.

The_Jeremiah

Nice to see another olds guy on here from Washington, Im in Ellensburg!

Thats a beautiful car you have there, I noticed you said you were switching gears but having trouble finding the gears? talk to brian trick on this website!

I think the username is 507olds? man i hope thats right.. haha

jdana24

Thanks, The Jeremiah. I communicated with Brian a few weeks back, and he was the one who told me that Richmond was not making any new gears until May 2013, and that I needed to start contacting companies to see if anyone had a set left. I found them Monda from Just Differentials which just happens to be in Cashmere, WA. They were delivered yesterday to the shop for installation.

olds 307 and 403

I bet with your ARH headers, you will be 10-20 hp/tq over the junk header numbers. Cool build. I like the stock look with a performance boost.

Indy_68_S

Not sure how I missed this thread, but Congrats, Jeff ! There's nothing like hearing it roar to life after going thru the build process !

My build and yours are almost identical with the main differences being your roller cam setup & filled x-over.

My dyno numbers were just a tick under yours and like 307-403 said, you'll prolly pick up a bit more with those gorgeous ARH headers....

oldzzy

Engine looks good, i'm sure you'll be happy with it. How do you like your American racing headers? Did you go with the 1 3/4"? I ended up going with the 1 7/8".

joesw31

I missed this thread as well! Nice build!

jdana24

Thanks Shane. I went with the 1 3/4" and I will be using new 2 1/2" stainless pipes. I don't have my car back yet, so I'll have to wait to answer your question. I'm sure (hoping) I will like them.

joesw31

What rear gear did you decide? 3.42 or 3.91?

jdana24

I went with the 3.42 gears.

lil_no

Looking really nice Jeff. Good to see things are moving along with your engine build and rearend gear replacement. Hopefully, I be at that state sometime in the forseeable future... Finally starting to get back on the Cutlass after a few months of only being able to work on it here and there. Actually got passenger side quarter tacked in tonight. Once I can get that welded and welds grinded down, hopefully things will progress at a slightly faster pace.

Again very, very nice... Also motor should sound even better with the new header and exhaust.

Noah

jdana24

Minor update. The engine is now back in the car, along with the new 3.42 gears, and many other restored parts that were put back in the car. Attached are a couple of bad cell phone pictures I took at the engine builders shop since I forgot my camera. It looks better in person than in these photos. Thanks to Dashriprock for sending me photos/specs of his vacuum pipe to spark plug bracket, we are fabricating a new one since these seem to be impossible to find. Now the last thing that needs to be done is to install the exhaust system. I'm having Nick at American Racing Headers build a stainless system for me which will bolt right up to the ARH headers. Has anyone used his ARH pure thunder series mufflers?

Indy_68_S

Yay ! Engine is back home in the car!

Here's some pics of the bracket in question for future reference....

Bracket2_zps26e94317.jpg

2013-02-05_19-22-26_49_zpsd40b591a.jpg

jdana24

Another quick update. Exhaust pipes and mufflers will ship from American Racing Headers on Monday, so should arrive by the end of the week to be installed. I ordered the valve cover to air cleaner vent tube from Inline Tube, however when it arrived it is for a 1969 and not a 1968 as was stated in their parts catalogue. Therefore, I will need to track down one of these to finish off the engine. Hopefully one of the members here has one I can purchase. I'll make a post in the Parts Wanted section. Below is a link to a short cell phone video my engine builder sent to me yesterday. It is just straight headers at this point, so it is a bit loud, but I think it will sound nice once the exhaust pipes and mufflers are installed.

Oldsragger

woow nice sound