Streetable 304 build

[Immortality]

Does depend on who's dyno I totally agree the old 286 should do 300+ but sometimes it doesn't happen. I don't know if all the ones I've seen do 300+ are on a Disney dyno.

I've seen 355's with 286's at 2 degrees retarded with a torque power only go 270 before. Don't know if it was tired or an extremely heart breaking dyno.

What I will say is Ive seen them run 11's and who care what the print out from the rollwrs is if the slip says 11's

Lazy on the compression? Stock bananas manifold?

TP did a 304 with their intake, 10.5:1 230° cam and made 400hp on engine dyno.

The old NZV8 series ran as cast 304 heads, milled for compression only(about 10:1 iirc) 234° FT cam with Harrop DP manifold and made about 420hp.


Personally, for a fun cruiser the stroker has to win, low down torque and no need to rev it hard which means no expensive oiling mods or exotic valve train parts needed to make a 304 live at high rpm.

 

[harrop.senator]

Lazy on the compression? Stock bananas manifold?

TP did a 304 with their intake, 10.5:1 230° cam and made 400hp on engine dyno.

The old NZV8 series ran as cast 304 heads, milled for compression only(about 10:1 iirc) 234° FT cam with Harrop DP manifold and made about 420hp.


Personally, for a fun cruiser the stroker has to win, low down torque and no need to rev it hard which means no expensive oiling mods or exotic valve train parts needed to make a 304 live at high rpm.

I'm unsure man it was on club dyno day. There were a lot of dissapointed people there but I didn't have a running car at the time so I couldn't compare numbers myself.

And no it had a low rise dual plane with throttle injection on it no bananas.

Last 355 I did for someone was 10.3:1 from memory with a 286 I dialled straight up. He annoyed me being impatient and selfish after I pulled it , disassembled it , individually 2k painted everything and re assembled it for a birthday present. Unsure if final tunes complete or what it made. Felt about 250 on run in tune.

On the run in tune from Al Gibbs it went fairly well , was very punchy ran out of puff around 5200 . With my old 2.5. Stall and 3.45's it made you smile and traction was an issue with 20s and ssl's.

 

[Immortality]

That's Odd, 286 should pull to over 6000rpm, maybe a bit lower on a 355. Cam timing maybe? For a 355 I'd also drop the lsa a bit 108 instead of 110. Cubes can handle a bit more overlap.

Personally I'd Never use the old 286 grind as there are better out there now. The original Crane grinds were fairly lazy, good and gentle on the valve train but leaves hp on the table.

 

[harrop.senator]

Yeah they were decent but they also had like 4 degrees of advance ground into them.

Mines retarded 4 degrees in mine and I think max power when it ran in the old car before it span a bearing was 6100?

I rebuilt it all and installed it to find the used transmission it had a broken parking pawl. So I rebuilt my original 4hbd and licensing cancelled my rego over some fines. Told myself do it properly then and respray the car before having it engineered and licensed again.

He had bananas which really choke and then get a second wind I was probably changing in the original fat spot before the second wind.

Usually 100 rpm max power drop per 10 cubes so 500 rpm earlier ending max power would make sense. Especially with the bananas. The extra cubes and cam would take them out of there efficiency range even sooner I'd say.

 

[Immortality]

This ride thread is worth a read and exactly in The ballpark power range in the OP. Then its evolved. It does have alloy heads which are overkill but beneficial as the car does time attack and track days so the weight savings over the nose of the car are well worth it.

82-VH-SS

 

[Loomesy]

Thank you for the replies. Yes 12k is the budget for everything from the sump plug to air cleaner. I will be assembling everything myself but budget includes all parts and machining. Will be fitting 4 bolt mains as well.

Cheers

 

[shane_3800]

Thank you for the replies. Yes 12k is the budget for everything from the sump plug to air cleaner. I will be assembling everything myself but budget includes all parts and machining. Will be fitting 4 bolt mains as well.

Cheers

For a 12k engine you're not going to need 4 bolt mains so thats just an expense for no power gains.

A main girdle will help with cap walk and only costs 300 last time I checked.

 

[harrop.senator]

For a 12k engine you're not going to need 4 bolt mains so thats just an expense for no power gains.

A main girdle will help with cap walk and only costs 300 last time I checked.

I'd spend the extra $270 on the 4 bolt mains. You should be align honing even adding a girdle and the arp studs.

You can definitely make use of 4 bolt mains in a 12k motor I mean Holden did it when they added a twin throttle body manifold .

Just means you're turning it past 6.5k on a regular basis

 

[harrop.senator]

Get yourself a quote from a local machinist with a good reputation man .

Check the price on the align honing/boring for 4 bolt main caps.

Boring the block out.

Tenth gram balancing.

Crank linish.

Resizing and fitting ARP rod bolts.

Get a quote for reconditioning the heads and a bit of a port clean up plus fitting all the required springs.

Then see what's left of the budget to work with after you know there costs.

 

[shane_3800]

I'd spend the extra $270 on the 4 bolt mains. You should be align honing even adding a girdle and the arp studs.

You can definitely make use of 4 bolt mains in a 12k motor I mean Holden did it when they added a twin throttle body manifold .

Just means you're turning it past 6.5k on a regular basis

It's way more than $270 for 4 bolt mains.
You say you know lot's about engine building but you don't know how much a 4 bolt mail conversion costs.

When you do the conversion you need to mill the webbs down drill and tap the holes then you need to bore the mains not hone they need a re-bore. You can't use a hone machine to bore the main tunnel.

Here is a three part video series on the boring process.