Well I decided to skip the T/A Nats this year and go to a local car show that benefited SMA which at the church that this was held at a couple had lost their child to SMA. Coming home I started to hear a random tick which sounded like an exhaust leak. The closer to home I got the worse the sound got. I knew something in the bottom end was going out and with about a 1/4 mile left to go I drove it home. Never lost oil pressure and no ignition miss but it is knocking quite loud.

I have a 350 short block sitting on an engine stand so I've decided to freshen it up and install it into my car.

Things I'll be doing to the motor:

New ARP head, rod & main bolts
New rod & main bearings
Melling oil pump, pick up & drive
Dart Aluminum heads P/N127322 (64cc, 200/75cc runners, 252/186 cfm @ 0.500, 1.43" springs, 0.610" max lift)
Fel-Pro gasket kit
New Comp Cams cam - getting their opinion on size
New Quick Fuel DP carb.

The only things from my 305 that I'll be reusing are
Edelbrock Performer RPM Air-Gap manifold
GM water pump
Holley fuel pump
Accessories
Crane Gold roller rockers
SLP Tri-Y headers and exhaust

I'll be working on this throughout the winter so I'll update as I go.

 

200 cc heads are too big, even for 500 HP. Find some 180s you like.

 

Why are 200cc heads too big? With a matching cam they'll work fine. One thing I would recommend is different pistons if your short block has the stock ones. You'll want AT LEAST 9.5:1 (or more) compression to get decent power out of this, especially depending on the cam. I personally would call Lunati about a cam. I found them WAY moer helpful as I was trying to choose a cam, which I ended up working with the tech (Steve Slavik, I'd recommend him %100) to get a nice custom grind.

Is this a roller block or not?

 

Yes this is a roller block from an 87 IROC. I know the stock spec says 9.2:1 compression ratio but when I enter the cc's of the piston (NHRA Stock replacement numbers) and with guessing what the deck height is I come up with either 9.3 to 9.4 on the compression ratio. I haven't measured the piston depth yet to know for sure. I can get a real thin head gasket too to raise the compression some as well.

I agree that 200cc is a little big but looking at Dart's 180cc (in the same product line, SHP heads) I wasn't too impressed with the flow numbers. The 200cc runners flow more like a better 180cc runner, Dart Pro 1 head. See Below

Dart SHP Head 200cc 252/186 cfm@ 0.500" lift
Dart Pro 1 180cc 257/182 cfm@ 0.500" lift
Dart SHP Head 180cc 248/170 cfm@ 0.500" lift

I wanted my exhaust numbers to be a little higher since I will be running a higher lift roler cam and the SHP heads are relatively cheap for an aluminum head as well..

I'm still in the planning stages and the heads haven't been ordered yet I still have a little more research to do on another set of heads before I make the final decision.

 

After more research and considering the cam selection I'm going with the Dart 180cc SHP heads. The cam selection is the XR282HR, 08-432-8

Specs (intake/exhaust)

Lift .510/.520
Duration @ .050 230/236
Adv. Dur 282/288
Lobe Separation 110°

 

Sounds like a big upgrade!

LT4 heads are 200cc.. Those LT4 engines made good power, GREAT power with a GM Hotcam.

AFR 195's make fine power too on a 350.

I've never seen a 180cc headed engine build personally. Either way, I'm sure we'll learn something.

Goodluck screwin it together, that cam will sound good!

 

I have the flow numbers in post #4 for the 180cc runners if you didn't see it and are curious. I'm use to building drag strip motors mostly and my alter ego was saying 200cc runners but my brain was thinking 180cc since this will be mostly street use for car shows and cruise-ins.

I've also considered a set of RHS heads as well but they are ~$200 more for each head (total $400)

I've pulled the pistons on the 350 and everything looks good for the build. You can still see hatch (hone) marks down the cylinder walls. Just need to hit it with a fine hone and brush to scuff it up a little so the rings will seat.

 

Trying to get a few more things done before I have to go under the knife for my back. I can't lift anything heavy right now so I have to rely on my son or friends to help me with the heavy stuff. I want to get the motor out of the 86 and the short block out of the 70 so I can move the 70 out of the garage so I have room to work on the 86. That will allow me to tinker with the small stuff while I recover from surgery.

 

I had a similar combo a few years ago but used the 200cc Dart Pro 1 aluminum heads. Same intake manifold, Holley 750DP, MSD ignition, flat top pistons, same exact cam too, the XR-282HR. I only ran that engine for one summer and never made it to the track, which I regret.

Put it in my cousin's pickup truck and it still works great, even though the cam is a little large for the weight.

Made 339rwhp/350rwtq iirc.

 

Just curious, what rocker arms did you have on there. I have Crane Gold 1.5:1 roller rockers that will also be going on this motor.

I also have SLP's Tri-Y headers and SLP 3" cat back exhaust as well.

 

I had Harland Sharp roller rockers, standard ratio.

 

Cool

 

Looks like I'll be doing most of the work next year. I've got three bulging disks in my neck pinching my spinal cord and I will be laid up till the end of the year before I can lift, push or pull anything of significant weight/force.

 

I know it's been awhile since the last post but I final got my clearance from my doctor so I can start lifting things again. Got my first order in and will be starting on the 350 block soon. I'm also helping a friend work on their 85 T/A that has a LT1 swap. They are pulling the motor because the front seal is bad and since they are doing a head cam swap, we decided it would be easier with the motor out and get in there to clean the engine bay up as well.

My short block order:

Main and rod bearings - Clevite
Piston rings - Sealed Power
Main bolts - ARP
Timing Chain - Summit
Cam locking plate - GM Perform.
Timing cover and rear main seals - Fel-Pro
Oil pump, pick-up and drive - Melling M55
Cam - CompCams 08-432-8

Now to prep and paint the block for these parts.

 

congrats on being able to start and glad to hear your ok!

 

A lot better than I use to be but not as good as I was 10 years ago

 

First parts have shown up, now to the garage to get things moved around to start working.

 

This past weekend I got the motor and pistons cleaned. Sized the piston rings and installed the main bearings and crank into my 350. The picture is before I torqued the ARP main bolts to 70 lb.ft.

Next on the to-do list is install the pistons, cam, oil pump and timing chain. Then it's time for purchase #2, the heads.

 

I await your thinking about each heads your going to get.

 

trying to keep cost in mind, original goal was under $1200. I'm not going to be running this motor at the track much, mostly street driving going to cruise ins and car shows.

After pricing aluminum heads and seeing what the cheaper ones were running I decided to spend a little more. I was thinking of the Brodix P/N 1021005, 1.47" springs for hyd. roller, 180/75cc, 64cc combustion chambers. I'm using an Edelbrock Performer RPM manifold and I'm thinking the smaller runners will help with lower end torque versus higher rpm flow.

 

Yep-Brodix does make a good head.Maybe go alittle deeper and have them CNC some minor port work.Tell them your goals and let them suggest what to do.

 

Good idea and I would have done that if I had the cash. My wife ask me "Whats wrong with the ones that came off the motor"

 

Got the pistons and cam installed this weekend plus a little bit extra. I haven't degreed the cam yet but I will before locking the bolts into place.

Now to yank the 305 out of the T/A.

 

https://www.thirdgen.org/forums/atta...50-photo-2.jpg

masterpiece, seeing that never gets old! keep on building!

 

Thank You

Got busy again this weekend. I had the A/C, carb and alternator already pulled off the 305 so I got busy and tore the rest down and pulled the motor.

 

Not much to report from this weekend. Waiting on parts form Summit and a nice day to paint my block. Finished pulling the covers off the 305. Found some metal debris in the bottom of the oil pan and the oil pump doesn't sound too good when spun.

My biggest hold up is getting the heads in. Been working on getting the money for it, its just our good friend "Murphy" has come a knocking and I had to get a new mower, washer and fix the dryer in a span of 2 months.

 

It's been awhile since I last posted and a lot has been done since then. I got the 350 all together and into the car. I ordered the heads around Labor Day and they didn't come in until near the end of October. I started to wonder if they were casting and machining these to order .

I got the heads on and I have been working on getting my header to fit properly. I'm also having problems with my header bolts. The SLP, Tri-Y headers have thick flanges. When using the 3/4" long bolts they only grab by 1-1/2 to 2 threads. I measured up the 1" long bolt that I have been using on the stock heads and it looks like it will bottom out before it will tighten properly. I guess I'll have to trim the 1" bolts by about 1/16" - 1/8".

Now to the pics. The last one I just put the covers and manifold on it to help keep the motor clean.

 

Oops forgot one

 

It's been awhile but my newest purchase came in recently. A QFT SR750 which is the last major purchase for this motor for awhile.

This will be done for spring and summer and I will be taking her to the T/A Nats this year as well. Already made my reservations at a hotel just down the street, walking distance.