Rock racer motor questions

jeepnchris

My name is Chris and I am building a motor to go in my rock racer. The motor is a 70s AMC 401 connected to a TF727 and a Dana 300. The 401 is at the engine builders because one of the cylinders was scarred. The engine builder has not had a chance to tear it down and tell me what need to be fixed. Our goal is to have about 550 hp plus use a 200 shot of nitrous. We need low end torque and to keep a pretty stable HP curve. Plans include new forged flat top pistons and edelbrock aluminum heads. The motor also has MSD ignition, Holley 900 cfm FI, MSD pro billet dist, Edelbrock performer intake. We are looking for suggestions from you guys on specific parts and/or configuration to achieve the stated HP numbers. Thanks! Chris

jeepsr4ever

You will need to build power with compression and you have that down. An extra capacity oil pan with road racing baffles should be used or a swinging pickup. You most likely looking at a cam with a 510-540 lift and a duration of 260 (in that area). You can check out KB silvolites dynamic compression calculator to find out where your compression will be with the cam you have chosen.

jeepnchris

How big would you bore out the block? Any specific pistons you would choose? I was planning on using your double roller setup, will that work with the electric water pump from CSR? Do you think the electric water pump is worth it? I was also wanting to use your oiling solution stuff. It looks like you have a few options - which one would you suggest for me to use? Any suggestion on what to tell the engine builder to do with enlarging any oil passages? Many Thanks! Chris

jeepsr4ever

I dont think you ened to enlarge any oil passages but I would use smaller hole cam bearings. I would also use an extra capacity oil pan. Think about a oil filter relocation system or the same system with a #534 plate this will allow you to use a Milodon swinging pickup in your oil pan (considering you buy a large capacity pan with holes for the pickup). Getting rid of the stock oil filter adaptor allows the use of higher flow filters and gets rid of many bottlenecks in the system. Use the Scorpion roller rockers they are best for AMC as far as aluminum ones go (check with Edelbrock on rocker reference). The cool thing about roller rockers is that they have a smaller oil feed hole and meter the oil slightly. I would also do a solid lifter cam but you are entering roller territory as well and there are some GREAT choices out there for rollers now. We can get you pistons for $650 a set shipped in flat top or a slight dish at zero deck ( zero deck is always preffered). I would also look to an Air Gap intake you will get a little more mid to upper end over a performer. With those Edelbrock heads and the right carb tuning you can really squeeze power out of that motor. I would go with a .030 + bore and depending on the block you can go further like .085" (always sonic check the block for thin spots, AMC V8 thin spots 1/3 way from the bottom of the cylinder on the side of the cylinder wall near the other cylinder usually towards the front) Here is what I would do if I was in your shoes and I didnt have budget concerns Bulltear parts 12.5-1 flat top pistons Double roller timing set Cam/dizzy gear set High flow aluminum water pump (non electric) Ultimate oiling kit (with Ni plated #626 or #534) Serpentine system Smaller hole cam bearings Tstat housing in Ni plate Other parts Aviad, canton or milodon road race oil pan King bearings Moly rings Edelbrock heads Scorpion roller rockers Edelbrock pushrods A very nice pair of electric fuel pumps Aluminum radiator Long tube headers Good ignition

jeepsr4ever

Before ordering pistons have your machinist check your deck height and if possible skim cut to clean it up. This can change the compression height dimension of the pistons and lead to less work at assembly time.

jeepnchris

I have (2) Barry Grant fuel pumps. How do you suggest I hook those up to the Holly Fuel Injection? I had originally ordered 2 because I wanted a spare but that can change.

For ignition I have the "MSD Programmable GAL-2 Ignition" part number 6530 http://www.msdignition.com/product.aspx?id=14276&terms=6530.

The distributor is (I saw a gear for that on your site - does it need something that is not included in the box?) MSD Part number 8519 for AMC V8 engines http://www.msdignition.com/product.aspx?id=5633&terms=8519 .

jeepsr4ever

Do the Barry Grant fuel pumps make enough pressure to run the Holley? If its the Holley 4bbl std issue 1000CFM old schoolie it should not be an issue. You should be good to go on ignition.