r3 street usage

[dartswinger84]

Looking for 59* 9.6" R3 block and wondering is it ok to use it in street? Not sure about part number yet. How about overheating problems?? Building ~650 hp (or more) engine and block must be good.
How about P5007552AB 340 replacement block? Is it strong enough.?

 

[greymouser7]

If there was a block that would hold your power goals, the R3 is the one. The magazines, etc. claim that the 340 replacement block can only to .080 overbore. A used X block is another possibility.

The R3 should be more than enough adequate for street performance. I am not sure if all R3 blocks have motor mounts or if some require motor plates. The only functional issues that you might develop, could spawn from overheating issues if you run a Siamese bore block (up to 4.22 bores advertised) that does not possess space in between the cylinders for coolant. Chevy guys manage to deal with this issue with their 400 small blocks. W2, W5, Brodix, or Indy cylinder heads would be required for that performance level. I think a 600hp street engine might be more difficult to build than race purposed engine would. If I remember correctly, a new block often needs significant machining of the deck on the R3 engines.

Brian & Fred Hafliger at IMM engines www.immengines.com/

Mike at http://www.mrlperformance.com/

and Ryan Johnson at http://www.shadydellspeedshop.com/

all have the answers, blocks(?), & experience that you want.

I am not an experienced professional, but I hope this points you in the right direction. Research & plan it out, and good luck!

 

[dodgedude]

I have also been told that a 340 replacement block can not accept a roller camshaft of any kind. Just FYI

 

[airwoofer]

Fergit those guys... OldManMopar streeting a huge HP SB. I'd try to get the combo from him.

http://www.forabodiesonly.com/mopar/showthread.php?p=1970136870#post1970136870

OMM Quote:

My Duster has a 700 lift solid roller on the street with a bronze gear. It has 1000+ miles at consistent 8000 rpm shifts. It is due for rod bolts and a freshen. The gear will be checked and replaced if needed. So far I see no play at the distributor. Good oil is the key and least pressure from the pump. Most guys just assemble the motor and run it with what ever pressure is there. I would always drop the pan and change the relief spring to lower the pressure if it is to high from tighter clearances.

I usually found the High lift solid rollers wear the lifters before the bronze gear is bad.

But again the gear is used to protect the cam. The coated gears are junk. They are like the coated fuel pump eccentrics.

Another thing that most dont do is set the clearance on the gears. This is done when machine work is taking place After installing the bushing. Cam and drive with pump in place if there is to much or not enough clearance an offset could be reamed in the busing on a on a mill. Just some things my sons machine shop does on high dollar race motors that he does on ours.

I said this before The same parts in different motors make different numbers. It is the machine work that makes the difference. My motor made 829 @ 7900 at the crank. stroker small block. Same motor from another shop on this site. 593 @7200. You either know our your guessing. I leave it to the professionals. Lucky to have one in the family.

 

[tubtar]

R-3 blocks have both magnum and LA motor mounts unless they are the " lightened " blocks......which were all low deck 48 degree if I am not mistaken.
They can run a roller cam in a 59 degree , but you have to make sure you have the right lifters. The problems are where people try to grind the valley for tie bar clearance......you'll hit water before you get enough room if you don't have the right lifters.
I can't agree with the " ferget those guys " sentiment.
Each builder listed has had a **** ton of success with the small block MoPar and obviously knows their business.
It sounds like the shop Airwoofer mentions knows their stuff too.
I'm not sure if there is a " best " , but there are a few " very good "s out there and I wouldn't be afraid to use any of them.
As far as cooling , read the chapter in " How to Build Big Inch Small Block MoPars " that covers this. There are a few tips that really make sense.
I am using W-9 heads on my 48 degree , but I feed coolant in the center core plugs and exit it through the heads , restricting the large passages at each end of the block to force more coolant through the center where you will be more likely to have hot spots.
It is easier with a remote electric pump , but can be done with a mechanical too.