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Lunati has introduced newer hydraulic roller lifters that are similiar to their high rpm used on LS1 engines. They claim the high rpm dont pump up as much as the standards, they have the lower oil band designed for the Cleveland bores, and are tie bar drop in design. No dog bones or hold downs to install. I agree oil mods can affect hydraulics, but depends on the degree of mods, as you already know. Just thought id mention it.

 
Lunati has introduced newer hydraulic roller lifters that are similiar to their high rpm used on LS1 engines. They claim the high rpm dont pump up as much as the standards, they have the lower oil band designed for the Cleveland bores, and are tie bar drop in design. No dog bones or hold downs to install. I agree oil mods can affect hydraulics, but depends on the degree of mods, as you already know. Just thought id mention it.
I am running hydraulic roller lifters in my 408 and they are the tie bar drop in design also. No other mods were necessary to make them work. Did not have to bush the lifter bores. Cant remember what brand but im thinking they are comp.

 
I spoke to the tech at Lunati as he mentioned those lifters-just not what I want.

The oiling mods that affect the hydraulic lifters are using these

http://www.summitracing.com/parts/mor-22050?seid=srese1&gclid=CNCah_f1zbcCFZNj7Aod4H0AGg

since I have decided to build for a power level far beyond stock, I feel the need to improve oiling to the lower end. I think the explanation in the listing is a simplistic way to put it, but close enough for Government work

 
Hey Jeff, good luck with the new powerplant. The restrictor kit is all I've ever used for oiling mods and have had good luck so far. With the last two clevelands I've built (one being an iron headed 408 very similar to yours) I also put a restrictor in the #1 main above the oil crossiver passage, right below the #1 cam bearing. The moroso kit does not supply enough restrictors to put one there as well. You Without this restrictor, if the #1 cam bearing if not installed perfectlyit can bleed out a lot of oil. might want to talk with your engine builder about this.

I also know that TMyer sells special cam bearings that precludes the use of restrictors.

http://www.tmeyerinc.com/exclusiveproducts.html

 
Thanks, I'll follow up on that as that is new information to me. Since you have done a similar build, perhaps you could answer a question.

With a Holley 850 Double pumper what jet size in both the primary and secondary would you suggest I start with, will I need to upgrade to the larger accelerator pumps and which accelerator pump cam worked best for you? I realize it might not be any more than a rough starting point but I am curious. I will probably do my initial start up on my 700 CFM double pumper as it is far friendlier on cold starts

 
I ran a 750dp with out stepping up to the bigger 50cc acc pump. This was a race car mind you but never had a problem getting up on the converter. Not sure about the pump cam and squirters. I believe I used 76 jets with a 3.5 power valve in the front and 86s in the rear.

Here's a startup video.



Also here's a good thread to read about the oiling mod.

http://www.network54.com/Forum/119419/message/1207711411/Here+is+what+I+did+to+mine

 
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Thanks, I'll follow up on that as that is new information to me. Since you have done a similar build, perhaps you could answer a question.

With a Holley 850 Double pumper what jet size in both the primary and secondary would you suggest I start with, will I need to upgrade to the larger accelerator pumps and which accelerator pump cam worked best for you? I realize it might not be any more than a rough starting point but I am curious. I will probably do my initial start up on my 700 CFM double pumper as it is far friendlier on cold starts
If you are serious about getting the 850 dialed in I strongly suggest investing in a wideband O2 sensor and gauge. You will also need to have the nerve to do some judicious drilling and tapping on your carb if it is not already set up with adjustable metering orifices. I can elaborate on this if you like.

This is how I tune a double pumper:

Start with the factory Holley calibration. Get the idle and transition circuits close with IFR and IAB tuning if necessary. There is no specific AFR to target other than one which makes the car run well at idle and just off idle and does not produce sooty spark plugs. Depending on cam timing, compression etc... it can be anywhere from 12.5-14:1. Next you want to tune your cruise AFR to target the smallest possible primary jet which you can get to without surging or sputtering at cruise speed. Depending on MAB size this will probably be between 72 and 74. This AFR at cruise can be as lean as 17:1 in some cases. Again it is all about how it drives. If it doesn't surge or sneeze lean is good. With an overdrive transmission it is possible that you will be cruising on the tslot at lower cruise speeds. Make sure you are on the mains when establishing main jet AFR even if it means tuning cruise in 4th rather than 5th gear. Next disconnect the secondaries and dial in the PVCR's for 12.5-13:1 WOT on primaries only. Because you have leaned the main jet for best economy you will more than likely have to enlarge the PVCR's. Make small changes. Now it is a simple matter of tuning the secondaries for the same WOT A/F ratio with secondary jetting. As far as the pump cam and shooter go that is a matter of trial and error. If the carb has a pink cam from the factory and you are experiencing a stumble and you are sure you have the pump arm adjusted correctly an easy place to start is to flip the pink cam upside down. In this position it gives a very aggressive initial shot similar to the blue cam. The REO pump is generally only needed in extreme cases. Again it is easier to disable the secondaries and tune the primary side first.

Obviously there can be a little more to it than that but those are the basics.

EDIT: Vacuum advance is mandatory for optimum lean cruise. Power valve should open at about 70% load.

 
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Alright, it is time for my update.

My Lunati Cam and roller lifters and springs are awaiting pick up at Fed Ex

My cylinder head is repaired and machinist said it was even less damage than he thought, so no problem.

My Headers were nitroplated and I picked them up this morning.

If I can borrow a truck tomorrow morning I'll take my spare block in to have it machined so I can order my rotating assembly.

I also sold some of my gun collection and raised enough to cover the balanced forged rotating assembly, and a few more parts, so I am feeling a bit better about it all.

I don't think it will be done by the 4th of July, but hopefully not long thereafter.

 
well neither engine was dropped, so the good news is my spare block is stripped and looks really good. Hopefully the measurements and testing will reveal it to be so.

Bad news is I didn't keep the rods and caps together so the set is essentially worthless, of course I have enough to make a real crappy 14 cylinder lol

 
Block is cleaned and decked. Machinist only had to take of .005 to get it cleaned up. Bore taper is .012 and he said in his experience it takes double that to clean the bore up, so .030 overbore is going to be the order of the day. Waiting on a call back with the measurements to order my rotating assembly.

I wonder if MME racing will build my assembly with carillo rods?

 
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