Would you ever use Rhoades lifters on a solid lifter cam?

[PackardV8]

All Studebaker V8s came with solid lifters. As is the case, there will always be some who think they want hydraulic lifters. There are no shelf/catalog regrinds for Studebaker V8 hydraulic lifters.

Some years back one Studebaker vendor was selling a hydraulic lifter conversion kit and was cagy about where he was getting a hydraulic grind. When I investigated, I found he was using Rhoades lifters on an Iskenderian ST5 (mild old school long ramp) solid lifter regrind. The result was maybe more even more noisy than the relatively quiet Studebaker solids and the only benefit I could possibly see is wrongly believing one would never having to adjust again.

I have never been able to bring myself to try this, but the subject has come up again in the Stude community. What would be your answer if someone asked you to build such a contraption?

{And yes, the customer is always right, but those of us who've been around know sometimes when the customer makes a mistake in what he buys, he's unlikely to admit personal stupidity and could blame the builder when someone asks why that new hydraulic cam is noisy.}

Noise aside, is there any general guideline of say 100# seat spring pressure and leakdown of the Rhoades lifters is going to end up changing the duration curve of a solid lifter cam? I'd think intensity/ramp design would also make a big difference, but again what do we know from experience, versus what we expect from theory?

[robert1]

Never used Rhodes on a solid cam. But I've used hydraulic lifters on a "solid cam" many times. Any time the rules say hydraulic lifters only.

[af2]

Never used Rhodes on a solid cam. But I've used hydraulic lifters on a "solid cam" many times. Any time the rules say hydraulic lifters only.

That is why you can.....

Regardless what 540 says the ramps on a solid lifter are way slower than a hydro............

[PackardV8]

Never used Rhodes on a solid cam. But I've used hydraulic lifters on a "solid cam" many times. Any time the rules say hydraulic lifters only.

That is why you can.....Regardless what 540 says the ramps on a solid lifter are way slower than a hydro............

My concern would be for street use the slower ramp of the solid lifter cam is slightly opening the intake way early and would increase overlap/decrease vacuum and low speed power more than it would increase top end.

So agree, for race, no problem. What is the real world street experience?

[robert1]

Then just get a stock regrind on your cores if that's a problem.

[af2]

My concern would be for street use the slower ramp of the solid lifter cam is slightly opening the intake way early

I see no way that is going to happen.

[Enigma]

Never used Rhodes on a solid cam. But I've used hydraulic lifters on a "solid cam" many times. Any time the rules say hydraulic lifters only.

That is why you can.....Regardless what 540 says the ramps on a solid lifter are way slower than a hydro............

My concern would be for street use the slower ramp of the solid lifter cam is slightly opening the intake way early and would increase overlap/decrease vacuum and low speed power more than it would increase top end.

So agree, for race, no problem. What is the real world street experience?

Lashing the hydraulic .002-.003 cold, coupled with the slight compression of the lifter as everything goes solid, won't open the valve nearly as early as a degree wheel and indicator would suggest.

[PackardV8]

I got a PM from someone with a great quote:

Their marketing copy says, " Rhoads' exclusive patented design reduces lift and duration on the low-end and restores them on the top. The unique construction reduces lift and duration at idle by approximately .010 in. to .020 in. Duration is reduced by approximately 10 to 15 degrees. Total lift and duration are restored at approximately 3,500 rpm. "

His opinion:
"Rhoads lifters should be called 'random lift and duration generators', since the manufacturer can provide no real info as to what lift and duration they're likely to produce at what RPM with a given spring pressure and cam intensity."

jack vines

[MadBill]

Beyond the already mentioned variables would be oil pressure at the lifter bores, oil viscosity and temperature, rocker ratio, valve train weight/inertia... Plus, if the lifter has leaked down on the opening side of the lobe, it will leak even more as it closes, leaving the valve to crash onto the seat from a significant height rather than being guided to a landing by the lobe...

[falcongeorge]

, leaving the valve to crash onto the seat from a significant height rather than being guided to a landing by the lobe...

I believe the technical term is "inverse lofting"...

[cv67]

Never understood wanting to do hybrids pick one or the other.
Only time I had to "check lash all the time" is using polynuts that were worn out..or adjsting them with the too many beers method.

[Walter R. Malik]

I have witnessed it with FORD factory solid lifter grinds in engines having NON-adjustable valve trains... simply worked OK.

I can't imagine building the engine that way but, it has been done.

[pdq67]

Anybody notice that the little bitty, -097 Duntov solid lifter cam is an OLD tight-lash cam lashed at .012"/.018" lash and the great -345, "30-30" solid lifter cam is recommended to lash way wide at .030"/.030"!

Ever ask yourself why Chevy made these two different designed cams?

Oh, and btw, that little old -097 Duntov was used in the 360hp/327FI engine and the 30-30 used in the 375hp, 327FI engine. And then they brought out the great old -151, 350hp/327 hi-cam....

Correct me if I am wrong, but didn't the 360hp/327 used 1.94"/1.50" valves and the 375hp engine used 2.02"/1.60" valves???

pdq67

[Walter R. Malik]

Anybody notice that the little bitty, -097 Duntov solid lifter cam is an OLD tight-lash cam lashed at .012"/.018" lash and the great -345, "30-30" solid lifter cam is recommended to lash way wide at .030"/.030"!

Ever ask yourself why Chevy made these two different designed cams?

Oh, and btw, that little old -097 Duntov was used in the 360hp/327FI engine and the 30-30 used in the 375hp, 327FI engine. And then they brought out the great old -151, 350hp/327 hi-cam....

Correct me if I am wrong, but didn't the 360hp/327 used 1.94"/1.50" valves and the 375hp engine used 2.02"/1.60" valves???

pdq67

OK, this is not really a correction but, an addition ...
The 365 hp and 375 hp engines from 1964 & 1965 were identical inside using the 30-30 cam and had 11/1 compression with 2.02" heads; one used a carb and the other had Rochester fuel injection.
The 360 hp engines in 1962 & 1963 had 11.25/1 compression both using the fuel injection.

Comparing different years is like comparing apples and oranges. Ratings were all fictitious and fudged, although 15 horsepower is quite a bit.

[PackardV8]

Anybody notice that the little bitty, -097 Duntov solid lifter cam is an OLD tight-lash cam lashed at .012"/.018" lash and the great -345, "30-30" solid lifter cam is recommended to lash way wide at .030"/.030"!

Ever ask yourself why Chevy made these two different designed cams?

Oh, and btw, that little old -097 Duntov was used in the 360hp/327FI engine and the 30-30 used in the 375hp, 327FI engine. And then they brought out the great old -151, 350hp/327 hi-cam....pdq67

Straight from Ed Iskenderian, who learned the trade from Ed Winfield, that Winfield designed the 097 for Duntov. Winfield was an old school genius from the dawn of US racing. However, the SBC valve gear was so revolutionary, more was learned as they were raced and as heads got better, so cam profiles began to be optimized for the new era. As good as it was in the day, by today's standards, the 30-30 is a quaint antique.