Killingsworth 73

I have a 1988 or 1989 Chevy 350 with a roller cam (no idea what cam), and I have a stock mechanical fuel pump, with the stock replacement pushrod in the pump.

I read somewhere that I should have an aftermarket fuel pump pushrod with a roller tip, to prevent damaging the cam. The car has been setup this way for over 10 years, and has never had an aftermarket pushrod, and probably been driven 15k miles.

Am I damaging the cam? Would the cam need replaced at this point, or just changing the fuel pump pushrod would be fine?

REELAV8R

I can't say for sure on your cam since we don't know what it's made of, billet or austempered iron, but on mine I got the blended polycarbonate pushrod to prevent damage to the cam lobe.
http://www.summitracing.com/parts/hrs-94475/overview/
The roller tip push rods seem a bit steep to me and potentially problematic.
Don't get a bronze tipped one. I tried that first and it immediately began to wear and eventually can mushroom making removal of the pushrod once it gets too short near impossible.
If your fuel pump is still pumping then I would say your cam is fine or at least minimally damaged and no cause for concern. The wear on the end of the push rod should tell the story when you pull it out. Should look new. If the cam did see some wear it could wear the blended polycarbonate pushrod prematurely, but that would become a real problem only when it stopped pumping fuel.

Killingsworth 73

Thanks!

bluedawg

You can use the composite, brass tip or the roller, but for a stock pump, I think you can use the stock rod, the need for alternate push rod styles and materials comes from bigger fuel pumps that have greater rates and stronger springs. In mine I ran the roller tip, expensive, but seems to work great.

ddawson

Mr Straub provided me with a new pushrod to use with his roller cam. Said some about being compatible.

gdh

After reading up on various fuel pimp push rods last year I opted for a composite one when I installed the ZZ383 last summer.

StraubTech

The pushrod fuel pump rod we make is 4130 Seamless Chrome Moly and we use an Ampco 45 material for the bronze alloy we use. This is same alloy used in the best bronze distributor gears.

If an bronze tip or gear fails, you tear the engine apart and flush it out. Pain in butt but you can clean it. If the composite stuff fails, you throw the engine apart as the fiber embeds itself into the cast iron.

REELAV8R

I remember trying to find a solution to the bronze tip issue.

In my search and talking to Howard's (take that for what it is worth, obviously they have a vested interest in this) I could find no failure's of the blended polycarbonate fuel pump pushrod.

The bronze tip push rod, if you do a search, you will find many, many failures.

bluedawg

I have had the roller tip in for about 12k miles and no issues.

68/70Vette

About mechanical fuel pumps. When I had a clone L-88 engine in my 69, I felt that top end performance was being limited. The mechanical fuel pump was the standard 400 Hp 3X2 fuel pump. At around 110 mph, the engine power just slumped, when it should not have. I've always suspected the mechanical fuel pump. My 68 has an Aeromotive Street and Strip electric fuel pump, and I'm planning on as least as much for the 70.

jb78L-82

With my Howards Roller cam, Howards told me no need to change the stock distributor gear or fuel pump rod…no issues. I think that the incompatibility issues occurred on early roller cams.

Solid LT1

I've know 3 expert builders over the years who have trashed fuel pumps running a stock push rod on them. For roller cams I use the bronze tipped push rods trying to keep things simple ( check them at about 10K mile intervals.) I built a vintage Fuely Vette motor once that regularly turned 7400RPMs at the track with its stock AC fuel pump.....definitely needed the lightweight push Rod on that build.

What are stock push rods good for? They make great punches in your tool box

StraubTech

Bronze tip or Roller can be used on any roller core.
OEM or Aftermarket light weight Chrome moly with hard tip on SADI or Austemper Cast cores.

An aftermarket lightweight fuel pump rod is a good idea for engines that will be street strip cars. The reduced mass of the lightweight fuel pump rod will reduce the chances of "floating" the fuel pump at the higher rpms.

If you "blast" off your OEM fuel pump rod you will find that the OEM rod has a hardened tip from the factory.

Killingsworth 73

Mine currently builds power at 3500+ rpm, with the Torquer 2 manifold. It pulls hard to 135ish mph - 5600 rpm. Doesn't feel it is lacking fuel up there. I'm not sure what is IN my engine or what my rev limits SHOULD be.

I might just go ahead and order a lighter polycarbonate push rod and throw it in. Not expensive and I would assume worth the risk (even though no damage that I know of so far).

Solid LT1

Think of it as installing a lightweight "Hammer" that is banging on your fuel pump lever......less damage than using a heavy weight one

If your build spends time going over 6000RPM, I think you should install the lightweight part.....not required for an Impala Station Wagon motor

Killingsworth 73

Sounds good. I need to get in your 12 sec club!

resdoggie

I'm using one from Howard's. No problem so far. Also using their composite dist'r gear. Again, no problem and I'm running their HR cam.