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Looking for RPM suggestions

W

wadwerks

Ok here are the specs I have built a 1725 with custom I beam rods, JE pistons 13:1 comp., aluminum flywheel, chrome molly push rods, Isky S-5 cam, duel valve springs, alum. crank pulley, ARP head, rod, and main studs. What do you think would be a reasonable redline? Also is there a high volume oil pump available and if so where would it be found?

Thanks in advance for the help, the engine is almost done just trying to get an idea of a rev limit. I have run Datsuns in the past and know it will never rev like that but dont really have an idea where to start. I was running it at 6,500 before changing the rods and pistons.
 
alpine_64

alpine_64

Donation Time
You can make a high volume oil pump.. there is 1 mod that uses MGA parts.. and apparently another method. Jarrid Gross (rootes racer) and Steve Silverstein should be able to point you in the right direction for that.

Safe rev limits? Well you were doing 6,500 before.. i think you can now do 6500 safely.. but to be honest i would use 6 as a red line and have a nice engine with decent HP that will last.. Going the extra RPM may not gain you that much more power.. but might cause you to start over
 
64beam

64beam

Donation Time
Hi,

I would agree with the redline previously stated as well. If you set up your torque band correctly you should need to go higher. I would also make sure everything is balanced nicely as well which will help it rev a little easier and freer.

Regards, Robin.
 
W

wadwerks

The big problem I have found is that on many tracks the stock transmission gearing is just horrible and spread to far apart so I need a few more RPMs to get through and out of corners and help make up for the large space in the gears. I find that ai am either to low an RPM in one gear or at red line the next gear down but if i can rev a little higher it would take care of my problem. The engine is balanced, blueprinted, port and polished and all the bearings have been polished.
 
sunbeam74

sunbeam74

Silver Level Sponsor
Jarrid should be able to tell you more about a HO oil pump setup for the 1725 but it involves using a MG oil pump inners. If it were a 1592 then simply use the 1725 pump and do the alterations to the output line and pickup.

As far as RPMs I usually stick below 6k in the 1725 - that's just me... The Sesslar Alpine was setup somewhat odd and I have always left it that way. The rearend is a 4:86 (they would usually run 4:22 and sometimes a 3:89 but these ratios weren't found with the car) but it has Overdrive to compensate for longer straights. It also has a Series III box. The ratios, though not great, seem even closer with such a short rear end ratio.

I also rarely run a longer track.

The Adrian Alpine has a 4:22 and a Series V box. It is a 1592 motor and I will be using 7k as my redline.

Steve
 
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