I'm rebuilding my 351m in my high school auto class and i'm ordering a master kit from northern auto parts and they give me two cam options and just wondering what one would be better,they are:
Speed pro CS1085R 1500-4000 RPM 204/214 dur .484/.510 lift
and Speed pro # CS1021R 2000-4500 RPM 214/224 dur .510/.536 lift

in not doing a lot to the truck getting a new intake a 4brl carb this summer when i have some more free cash. I have a new timing chain (Edelbrock True Roller Timing # 7821) and another question is do i really need a high volume oil pump?

 

Do yourself a favor and stroke it with a 400 crank. Then use the 204/214 cam. You could also skip the 4 bbl intake and replace the 2 bbl with a Holley 500 cfm 2 bbl. Add long tube headers and enjoy.

 

What will the motor be used for? The first cam is more of a torquey cam, and the second one is a hp cam. If it's going in a truck, my vote goes for the first one. If it's going in a car, get the second one.

 

I used a comp cams 265DEH-good respected cam for the 400's at least-have a look at the spec sheets and see how they compare. No you dont need a HV oil pump-these can put too much load on your dizzy drive gear and strip the roll pin. Standard pump, strip and ensure there is no casting sand or machining swarf. Check tolerances between lobes and cover plate with feeler gauge and reassemble with industrial vaseline (white petoleum jelly) and any other assembly lube you prefer, (probably even a little gear oil at a pinch-heavy enough to stay there until everything going ok) and prime the oil pump once installed on the engine with a drill until you have oil coming out of the rockers before installing the dizzy and starting. Tolerances on mains, rods and cam bearings probably more important but if you are only doing a cam, if the OP is ok than no probs. TMeyer does a nice cam bearing mod but that is really only something you can do on an engine rebuild.
Another trick is to fit a HP aftermarket relief spring to the oil pump. These are done by Moroso (ala Jack Roush) and not that expensive $10-20. This will bump pressure up to 90-100psi. Spring can be a mongrel to get out of the pump or more importantly the cap holding it in, but thats another story. My 400 is running around 750kpa 100+ psi at idle cold and drops to 550-600 (80psi) when hot and thats after approx 1000km's since rebuild. In saying that I have seen reports that people are are getting around 80psi with standard spring on a good well toleranced (blueprinted ) rebuild. What is your OP now??

 

im not sure what the op was. im doing a complete rebuild in my auto class. took out the pistons friday and the bearings were wore into the copper. how would you change that spring out in the pump? and where would i get that spring? this is my first complete rebuild. im planing on getting an op gauge and others when i get it rebuilt because my truck only has the dummy lights. it would be idling and it would kick on after about 20 seconds of idling so it had to be low

 

My 400 did exactly the same thing after a cam and head change. when idling hot in gear at a stop sign or such the light would flicker. I don't like that and eventually bit the bullet and rebuilt the old girl.
If you are doing a full rebuild, check out TMeyers site about cam bearings and the oil gallery mod. piece of cake and have a chat with your tutors about it but it all makes sense to me and I believe worth the effort. I had my crank in and checked after a few dramas, otherwise I would have done the bearings and mods myself. I had an @#$ of a time with that spring. If there is a better way I truly would like to know!! lightly knock down the plug/cap that retains and covers the spring. Remove the split pin (cotter pin whatever you call it) and throw it away as you will get a new one to replace it. then using a generous size soft faced (nylon would be good)you have to hit the oil pump while holding it in your hand. Now this is a pain as I cant remember which way I hit it as I did both till I found the way that works, either straight above the cap or the complete opposite on the other side of the pump. The inertia of the blow works on the spring and it pushes on the cap. You have to hit it quite firmly and be careful as it gets close and I would use a rag so it not only doesnt bugger off accross the shop or cut your hand. Re-installation is a lot easier, press it back in with a vice and 3/8" or 1/2" socket that will fit in the bore and remember to replace that split pin. If you've done mechanical work before you can sometimes get away with a used one if it is actually ok, but for the sake of 10c another one is the way to go. They are only mild steel so anything the right diameter will work in a pinch but the split pin is easier to work with.
Try here to have a look and then summit/jegs possible for p/a:
Moroso : Category Display

 

It would be easier to just buy a high pressure oil pump, these are available for most engines. Just me, but I'd do a high volume pump instead.

 

Yes but the idea is to not have the HV pump. As written earlier the spring is probably not needed as the engine assembly and bearing clearances (ie grinding crank to suit bearings etc) are really the most important thing.

 

I used HV's on two 400's, I built, one I pulled to replace with the built motor, then later reinstalled in the same truck. Both benefitted from the extra volume. These motors loose too much pressure by the time the oil travels thru the cam gallery for most. I suppose if you rebuilt one and went thru the bearing tolerances(blueprinted) with a fine tooth comb, you could get by with a std volume pump. Even with an external line to supplement the rear main, the pressure drop at idle is scary enough with a HV pump.

 

As written earlier, I have a standard pump with an HP spring. My oil pressure line is at the rear of the block tee'd into the sender (theoretically) the lowest pressure in the block. very happy. When I rebuilt the block I plastigauged the crank and rods to check and they were fine (whatever they were allowed in the manual) as was the end float in the crank. Ultimately the problems I mentioned before didn't happen for you and as they didn't fail it's a hard point to argue.
I also would like a dollar for every rebuilt 351C in the aussie Street Machine mag that had an HV oil pump. I tried to get back oil pressure in a worn motor with a HV pump, but replaced the main bearings as well. Bad Idea. it was worse then when I started. I believe that it was because the old bearings were worn in and sealed better than the new bearings. I now have a HV pump with about 6 hours on it sealed up in the shed. May come in handy sometime. At the end of the day pressure isn't volume. All clearances being fine you will get the pressure that the relief valve in the pump lets you get. A HV pump does this with a larger geroter which puts more load on the drive pin but is still only pumping as much as he relief valve lets it..

 

As written earlier, I have a standard pump with an HP spring. My oil pressure line is at the rear of the block tee'd into the sender (theoretically) the lowest pressure in the block. very happy. When I rebuilt the block I plastigauged the crank and rods to check and they were fine (whatever they were allowed in the manual) as was the end float in the crank. Ultimately the problems I mentioned before didn't happen for you and as they didn't fail it's a hard point to argue.
I also would like a dollar for every rebuilt 351C in the aussie Street Machine mag that had an HV oil pump. I tried to get back oil pressure in a worn motor with a HV pump, but replaced the main bearings as well. Bad Idea. it was worse then when I started. I believe that it was because the old bearings were worn in and sealed better than the new bearings. I now have a HV pump with about 6 hours on it sealed up in the shed. May come in handy sometime. At the end of the day pressure isn't volume. All clearances being fine you will get the pressure that the relief valve in the pump lets you get. A HV pump does this with a larger geroter which puts more load on the drive pin but is still only pumping as much as he relief valve lets it..

 

X 2 that (get the 400 kit w/crank, the pistons same diameter but different wrist pin location)and a high volume oil pump on these engines is good insurance. Better would be 400 crank and a set of Tim Meyer's 400 pistons with a tad more compression.




Me personally, no headers .... PITA years and years ago, BT-DT.

 

Just found double posted?

 

Never heard of bearings "sealing". The problem with these motors is the main oil gallery is also the lifter gallery, this is where the pressure is lost on most. Your motor probably had tighter tolerances here than most, hence more pressure at the rear main. Pressure and volume are related, if you don't have enough volume, you won't have enough pressure, no matter what relief spring is in the pump. If there's not enough pressure at the rear main, then it's loosing volume somewhere, could be either the bearings or oil escaping via the lifter bores in the main gallery.

 

Bearings "sealing" is the best way to describe it, and the only way I can get my head around why brand spanker bearings had worse oil pressure than the old ones, the clearance on the bearings being the issue and an HV pump did no help what so ever. More so worn in and matching the crank journal perfectly. Agree with you completely on the clearance's, as ultimately that is the defining restriction for oil pressure in an engine and why it usually is what determines a rebuild. Really what you are using an HV pump for is to allow for tolerances on the large side. I did no extra machining other than the shop grinding the crank to suit the bearings and from what I understand that is common (best??) practice and I was probably lucky the lifter bores were fine. Everything else just fell into line with the tolerances from my rebuild manual, so nothing special done there, so I cant say why it was tighter than most. Just remember you've been using HV pumps for a while and keep using them. You haven't swapped and changed to fix a problem so as long as you arent having problems with the dizzy drive it's a no issue really. Pressure is only related to volume as the restriction and relief allow it to be. My case shows that if the clearances aren't any good, a HV pump won't necessarily help. Putting an HV pump on a rebuilt engine and saying that is the reason it has great oil pressure for it's life is flawed as it may have been fine with the standard pump.
BUT I also recognise that if you re happy with the results and you are having no problems, why would you change? At the end of the day I went off one of the guru's of the 351C's, Jack Roush who raced a bucket load of them, as well as I guy who rebuilt them for powerboat racing, after trying to fix a low oil pressure problem with an HV pump that didnt work. You are putting them on because you believe you have to and i cant dispute that as it is your opinion. By the way what is the go with the double up posts?? did it to me and Tbear.