302 to 331 Engine build

[TexasEd 188]

My engine has been burning oil in at least two cylinders and misfiring in at least one so while my car is being painted I'm having the engine pulled and a local builder is going to rebuild it for me.  I think this is pretty set.  I've dreamed of doing something like this since I got the car in 85 but I have someone helping me put the parts together in a package that should work together. Before this was put together as a package I used to read comparisons between AFR and TFS or Air Gap vs Weiand Stealth

Goal is fun to drive street machine with torque and the ability to hwy drive with lower RPMs.  I want a little rumble but not a race cam that is super lopey.  I'm getting a used built T5 to replace my C4 at the same time, the original builder will go through it and inspect it.  Also new gears in the rear, probably 3.5 or 3.7.  I already have a set of JBA shorty headers and beautiful exhaust.  This kit is more expensive than I was planning but it is all top shelf stuff.

• Bore and hone my original 69 302 block
• Scat 331 rotating assembly
• Trick Flow 11r 170cc heads
• Trick Flow stage 1 cam
• Edlebrock RMP Air Gap intake
• Roller conversion
• new timing chain and cover
• Melling high volume oil pump
• Moroso baffled 7 qt pan
• probably going to replace the original distributor

Builder wanted me to do a 347 and I deferred to the 331 and he is good about listening to me and pushing where he should and going with what I am comfortable with.  Things that went through my head before were 351W vs 302 based stroker.  Sticking with the C4 and doing gear vendors vs AOD or T5 and then this built T5 was available at a good price.  T5 is supposed to go in the same spot as the C4 shifter.

Engine gets pulled out in a couple of weeks and we'll order parts after the initial tear down and inspection

A few things I have not decided on are replacing the starter, new alternator and what tachometer to put on the steering column.  Leaning towards a Pertronix distributor with a rev limiter.  

[RPM 1,190]

Sounds like a good plan. Merry Christmas brother. 

[det0326 179]

Merry Christmas Ed. The only thing I would be concerned about is some of those stroker cranks were having problems with the counter bore on the back where the convertor snout slips in. I know u said that u were going to use the T5 so there may not be any problem for your build, just mentioned it in case something changes and u use the auto, have your builder to check the dia. and depth.

[EastYorkStang 63]

Keep us posted with the progress

[smh00n 87]

My thoughts, having just built a 347 from a late roller block.

I have a MSD pro billet distributor with a 6AL CDI box. I've never had an issue with spark or ignition. Thoroughly recommend this set up or the ready-to-run option which is neater and a bit cheaper.

Hi torque starter motor with a relay. Again, throws the motor over with no hesitation. Both of these have been used on the current 302 for the past few years without fault. 

I went initially with a Lunati cam, p/n 20350711 which has reasonable duration and about .550" lift. I have now ordered a 20350712 which has slightly more duration, lift but a 110 LSA (as opposed to 112). This may be a bit over the top, but I am also using a TKO600 and 3.5 gear, so we'll see.

Dual row timing chain is a must. If you are building this yourself, I recommend the adjustable gear which allows you to easily set cam timing without pulling the gears. If you go with the dual row, they need to have counter sunk set screws on the cam retaining plate, which is not hard to do.

I have Dart Pro 1 heads which are 195cc, 2.02/1.60 valves and 58cc chambers. Looking at 10.5:1 compression. The AFR seems to be the pick of the litter at present. Look up Eric Weingartner on you tube - he has a lot of head flow comparisons so you could maybe confirm or confuse your head choice.

The RPM airgap is a good choice, they seem to have a very good rep around the streets.

I have a Holley Sniper EFI on it. Totally happy with it, love the cold starts and driveoff performance, it integrates into the MSD stuff so you can set timing, radiator fans can be turned on and off at your choice. If your financial statement can cope I would certainly put it on. They can be hidden somewhat and not look modern but there are at least 4 cables coming off the unit.

I think the 331 is a good configuration, it will rev quick but the pistons don't have rings coming through the gudgeon pin with the concerns there.

 

[det0326 179]

10 hours ago, smh00n said:

I went initially with a Lunati cam, p/n 20350711 which has reasonable duration and about .550" lift. I have now ordered a 20350712 which has slightly more duration, lift but a 110 LSA (as opposed to 112)

I used the 20350712 in a 351 bored .040 over and really loved it. Had plenty of power I think u will like it.

[TexasEd 188]

Starting to lean towards the 347.

I have a January 1969 build car so a very early 302 block which I hear is good.  I'm painting the car at the same time so I only have enough to do the engine and the T5 transmission is going to be a good deal so I'll squeeze that in too. New gears in the 8" rear is the plan instead of a new housing.   I think I'll be on the edge of the T5 and the 8" but since I am more likely to have a road race track day than a 1/4 mile I think I will be ok.  

 

[smh00n 87]

The Scat and Eagle cast cranks seem to be very strong. I have heard of a 302 dropping a a valve with major carnage, but the crank was still in the broke block in one piece. Similarly, somewhere on youtube someone has a 302 with a split in half block that the Scat cast crank is still in one piece. I don't think you need to buy a steel crank is the message here.

There's no replacement for cubic displacement which is why I went 347.