Don Terrill’s Speed-Talk

In this day and age with readily available good heads and hydraulic roller cams that were typically solid roller only grinds 20 years ago as a point of reference.

What do you consider to be the max lift and duration you'd run on a street car,

For clarification here.. standard SBC core and base circle, will idle in traffic, not eat springs or lifters and actually live for 100k with nothing but regular maintenance hydraulic roller, and something you could get in and actually drive 1200 miles non stop on a trip.

Aside from maybe needing to check lash every 20k I am talking about a 10.5 to 1 350-383 with efi or carb. Rough idle wouldn't matter, but street car power range of 2500-6500. And a typical 180-195 head with modern chambers and around a 2.0 or so minimum cross section 23° deal.

How big would you pros feel comfortable going if you were handing it to the average person that knows only gas, oil changes. Mechanically challenged individuals who would flog it.

there are plenty of more knowledgable people than me on here but I don't consider link bar lifters as 100,000 mile durable, so the lift with factory type lifter retainers is all I would use-approx .550" supposedly

I pulled my distributor weekly looking at the gear wear when running a roller cam.. that roller cam made me nervous all the time.
I like my flat tappets with good oil and good lifters for my daily drivers and I do pull heavy loads 5500+ lbs sometimes in my street car not including the 3600lb car I am driving.
My favorite cam is the 280H 230@ .050 I can still tune 15 MPG from that cam with NO overdrive and a 3.70 gear.

Largest I have ran and ran it for 2 years and 35,000 miles a year was 235-245@ .050 and .500" lift 108LSA solid flat tappet.

Have also ran the 292H 244@ .050 and ran a 252@ .050 and .571" lift using 1.6 rocker flat tappet solid in a buddys truck for 3+ years ..gas sucking pigs that I would not want to take on a 1200mile trip.
But reliability was fine.
Open spring pressures under 300 on most and the high lift solid was 340 Open pressure.

We have some really good valve springs today that you can get by with a lot less open pressures.

If I am driving a long ways I draw the line at 230@ .050.
That in a 350" with ported iron heads will stick a car in the 12's in the 1/4.

All the above were shifted at 7000 rpm or more just about every day they were taken out.

100,000 miles is not that far and if you must re-lash every 20,000 then something is wearing out.
My lash never changed on my solid flat tappets.

I would think 230 @ .050 and nearly 600" lift on a roller would be very reliable today

I ask because to be honest the engine I am building is new ground for me, factory roller thrust plate, spiders and dog bones with Delphi lifters hydro roller 228-232 @50 .575/.575 lift. 110 lsa 107 icl Good manley pushrods, scorpion shaft rockers of good quality and afr 195 street eliminator heads in a 383, with 10.5 to 1 compression. C950 Efi, good headers zf 6 speed, 3.45 gears.

I am just trying to get a better understanding of how often I should be checking lash and springs for wear with regular street use. In the spring through fall months I plan to use it as my daily commuter car, about 75 miles a day round trip, I have no problem with any increased maintenance penalties, it will never see more than 6100-6200, most likely will rarely see 5500. I know the heads, springs and rockers are total overkill for the low rpm. Point was to have it be quieter and ultra reliable, with room to grow should I build a forged shortblock down the road.

I will in all likelihood put 5000 or more miles a year on this thing, and I am trying to get an idea of a typical maintenance/inspection schedule for the valve train.

I would check valve springs at the 5000 mile mark for pressure losses. And being a scared cat with rollers I would check lash every week for a month or 2 and check distributor gear wear. If nothing ever changed during that time I would not be hesitant to just drive it and check stuff on a yearly basis.
You could leave springs on the head and check them with certain tools.
You may be surprised how long they do last.
Some valve spring types last longer than others.
I do not think with a hydraulic you will ever need to re-lash it. Unless something is being beat apart.


I will say this though Run good oil and keep coolant temps in check. Those lifter roller bearings take a beating.
That scares me the most and distributor gear wear.
Others may chime in on those aspects.

Built one for my son 4 years ago almost identical. The main thing is the distributor gear. On a steel camshaft run the melonized gear. If is a cast cam core any gear will work. We set the pre-load on the lifters ran it and double checked after a week and haven't had a reason to re-check. 50+ miles a day to from his work.

I have a customer street/strip guy who has a 393 Ford small block who street drives with 1.5/1 rocker arms having around .590" valve lift but, changes rocker arms to 1.72/1, (around .680" valve lift), for those weekends at the strip.

Walter R. Malik wrote: ↑Mon May 04, 2020 11:22 am I have a customer street/strip guy who has a 393 Ford small block who street drives with 1.5/1 rocker arms having around .590" valve lift but, changes rocker arms to 1.72/1, (around .680" valve lift), for those weekends at the strip.

That's not a bad idea, I've bounced that around for myself in the past. I'd have to really trust the person I gave that advice to...to not cause a disaster. I'm still regularly amazed at people(s) that are into this hobby's ability to mess operations like that up really bad

.575" lift with AFR's listed .600" lift is too close for me, have to check the actual install distances, millions of roller cam SBC's and 4.3 v6's using the GM distributor gear-thats what I would use

i think you will be just fine. 25 some years ago i had a 327 with a solid roller, mid 230 duration @.050, .597 lift 110LSA. it idled incredibly smooth, and it drove from sandiego to minneapolis just fine. with a modern hydraulic roller, it would have really been sweet.

If I wanted a comfortable 100k I'd prob use a GM cam, small cam co's(compared to an oem) don't have the R&D budget.

I run the Chevrolet ASA Cam cut @ 113 from Howards in a 416 LS engine with Frankenstein LS3 heads, and an LSX dual plane intake with 50 lb injectors and a 1000 cfm 4 hole throttle body. I'm not sure more cam would be beneficial on the street. I run N/A and have more torque than my tire can bare. Valve springs are the tipping point. A good set is well over $500. The valve train is the weak link. Cams over 235 get into stall speeds and or rear gearing and drivability becomes an issue. I think your better off with a mild set up with a very nice 4.0 Whipple screw blower sitting on top. Cheers

It has a pressed on cast gear on the cam. It is of good quality and compatible with the factory distributor gear.

Heads have decent springs. I will definitely keep an eye on them.

Just a fair weather toy, but often I live at work. So I would like to enjoy the car as much as possible. Having a 35 minute ride to work in my hotrod has to be better than doubling down on blood pressure medication hahahaha.

Bill Chase wrote: ↑Mon May 04, 2020 6:44 pm It has a pressed on cast gear on the cam. It is of good quality and compatible with the factory distributor gear.

Heads have decent springs. I will definitely keep an eye on them.

Just a fair weather toy, but often I live at work. So I would like to enjoy the car as much as possible. Having a 35 minute ride to work in my hotrod has to be better than doubling down on blood pressure medication hahahaha.

The street cam gear thing is not been around as long as roller cams have been.
I have a 740 lift hyd. roller 117 LSA in my shop truck driven daily and in the last 5 years I have reset the valve 1 time.
Idles fine with a 2000 converter in my dually drivability is great in town and on long drives no worries. Anything with a tight LSA will be a bitch in stop and go traffic if its a std. shift I did that many years ago and hated it

Why was the mt a bitch, want to surge and jump with throttle tip in, hard to not get tickets?