KBRVETTE93

I'm building a 383 stroker and am wondering whether to just replace the old pump with a new stock one....or save the old stock casing and go to an electric pump.

Can an electric pump keep up the demand with high rpms?

I understand that the electric can be worth 6 h.p. is that the right direction to go?

BrianCunningham

I have one on mine now. 55gpm

I know mechanical race pumps run about 110gpm.

The electric is great for autoxing, but the out on a track I've had heat issues.

I'm putting a stock one back on for a new engine.

KBRVETTE93

Thank you so much!

RedLS1GTO

I have a 55 gpm Meziere electric on my 383 LT4 now. I have only had it out on relatively cool days ~80 degrees so far but it works great. The only reason that I have it on the car is because I broke 2 mechanical pumps in a 2 hour span and didn't want to deal with that headache any more. I do carry a spare GM HD mechanical with me just in case it isn't up to the task. I've gotten to the point now where i can change it in about 20 minutes.

EDIT: I might as well share what happened to me so I might help somebody else in the process. If you are going to stay mechanical spend the $ and buy a HD pump. I turn ~7,000 rpm and I don't think the stock pumps like that too much. The first pump that failed on me was indeed an HD that had been in the car for quite a while. I think it failed because for the majority of the life only water was run through it with nothing lubricating. When it came out the bearings were pretty tight and it was actually the drive spline gear on the pump that let loose. I replaced it with a NEW factory style Duralast pump from Autozone. After only 2 hours it came apart as well. This time the actual impeller came apart in a way that I would describe as a catastrophic failure. When I compared the internals of the 2 pumps the difference was astounding. The GM HD pump was a huge step up in terms of materials used. The impeller was amazingly cheap in the Duralast in comparison and after looking I am not shocked at all that it failed at 7,000+ RPM and 110+ gpm. There were 2 bearings for the drive shaft vice the one in the Duralast and even that one was very cheap in comparison.

Readers Digest version: GM HD pump failed because of age and lack of lubrication. Replacement (new) Duralast factory replacement broke because it was a cheap P.O.S.

Whether the electric will be enough in my case is yet to be seen, but no matter which route you choose get the best available.

Mojave

I've run a stock reman replacement pump while turning 7000 rpms with no issues. Above around 3600 rpms, the stock pump flows more than an electric pump. If your engine spends a lot of time above that RPM continuously, a mechanical pump will flow more.

ScaryFast

I would stay stock. I bought into the hype a few years back, and therefore have a Meziere HD on my 383. It struggles on hot days, I don't like my water temps - they are not unsafe, but they are borderline. I've touched 240* too many times during a race.

There are a lot of variables here, such as radiator size, HP, etc, but for a track car I like the stock pump. If it weren't for a bunch of unecessary cost and effort I'd go back.