426 HEMI Question?

[gks1964]

What 1/25th scale kit 426 HEMI would guy's rate the best to use in NASCAR builds? 

[dwc43]

The Johan Petty Superbird is the only kit that has the single carb intake that they used on the early Hemi engines. But even that's not accurate for the late 60's early 70's engine. You could take and cross ram intake and make it look something close the rat roaster single carb intakes. Other than that, most any Hemi will work. After all they were just slightly modified street engines back then. They also used a single 1050 Dominator, but not like the ones you see today. They actually had 4 small stacks on top of each bore.  Those last 5 pics of that intake is one that I actually own. Nothing will fit on it but a Dominator carb. 

 

[dwc43]

The headers on that Johan Superbird are very correct for those engines as well. I tried to fin a pic of it on the net, but no luck so far.

 

[afx]

Think these are the Johan headers.

[gks1964]

11 minutes ago, afx said:

Think these are the Johan headers.

Those are the one's Howard (Radar43) sent me a set! Soon I'm going to try to mold and cast them!! The bath tub intake I have already cast along with the dry sump oil pan and reserve tank!  

[gtx6970]

6 hours ago, afx said:

Think these are the Johan headers.

I have serious doubts this style header was used on anything after maybe 1964 or 65 .

These are a copy of the exhaust used on the factory built 1964 and 1965 Race hemi cars. By 1970 NOTHING used them as far as I know

 

 

PS, is the correct bathtub nascar intake even avail in stryene form ?

Edited August 13, 2020 by gtx6970

[gks1964]

23 minutes ago, gtx6970 said:

I have serious doubts this style header was used on anything after maybe 1964 or 65 .

These are a copy of the exhaust used on the factory built 1964 and 1965 Race hemi cars. By 1970 NOTHING used them as far as I know

 

 

PS, is the correct bathtub nascar intake even avail in stryene form ?

No but I have some nice one's in resin!!

Edited August 13, 2020 by gks1964

[gtx6970]

Just for reference.

Appears to be either 1970 or 1971 Hemi B body Plymouth. Nascar

Steel tube headers used . Not the earlier kit supplied pieces

 

 

[gtx6970]

[gks1964]

Great pix! Very similar  to the headers I used on my '69 500.

[Force]

The best kit Hemi engine to use, well I like the Revell Hemi's from recent developed mopar kits but you need some parts to make it look right as there is no kit engine that's correct from the box.

The NASCAR 426 Hemi "Bathtub" intake manifold was available with a larger depression and wider port spacing for 4500 series Holley Dominator carburetors as well as the smaller 4150 series 750-850 carburetors.

This one is for 4500 series Dominator carburetor

 

and this one for 4150 series 750-850 style carb, they were made both in magnesium and aluminum

I don't know how long they were using Holley Dominators and as I understand it the 4500 series Holley Dominators were first used in NASCAR on 1969 Ford Torino Talladega and Mercury Cyclone Spoiler with the Boss 429 so before that there were none, and after 1970 the Hemi's (and the aero wing cars) were restricted to smaller engine displacements and the Dominator was too large for those engines and I suspect they stopped using them then.
And it's a lot easier to find old "bathtub" intake manifolds for 4150 series carburetors than for 4500 series Dominator carburetors, that's why I think dominators weren't used for long.

Here is a picture of a Plymouth Superbird getting a new piece in it and you see they use more modern style headers and not the ones in the Jo-Han kits.

RIP Maurice Petty

Edited August 29, 2020 by Force

[gks1964]

Force those are great pix!!

[Force]

Yeah I know, that's why I posted them. 

[yellowsportwagon]

Those Johan headers were only used early on not by late sixties.

[Vietnam Vet67]

In the picture of the open rat roaster manifold you will see ribs on the floor of the end runners, one on each side of the manifold. The original manifold didn't have those ribs and the fuel/air ratio on those end cylinders was all over the place. So we would epoxy popsicle sticks of different heights and thicknesses between those cylinders and run the engine on the race dyno at the Chrysler Tech center and try to even out the fuel/air distribution. Those ribs on the floor are the result of that work.

[gtx6970]

original 1969 issue Nascar Daytona headers.

 

 

Also,,,,, I came  across this . The restoration of the original #88 Dodge Daytona of Charlie  Glotzbach

 

https://www.bigirongarage.com/1969-dodge-charger-daytona-dc-93

Edited September 1, 2020 by gtx6970

[gks1964]

49 minutes ago, gtx6970 said:

original 1969 issue Nascar Daytona headers.

 

 

Also,,,,, I came  across this . The restoration of the original #88 Dodge Daytona of Charlie  Glotzbach

 

https://www.bigirongarage.com/1969-dodge-charger-daytona-dc-93

The Revell 68 Charger has a set. I used them on my 69 Charger. I have another set that I may make copies for all the MOPARS that I have on my list!

Edited September 1, 2020 by gks1964

[Force]

I feel we have to put some things straight regarding the intake manifolds.

The Hemi "Rat Roaster" is a two piece bolt together aluminum short ram intake manifold made and sold by Edelbrock and was available in a couple of versions, RR-1 inline dual 4-bbl's, RR-2 cross ram dual 4-bbl's and RR-3 single 4-bbl and the "Rat Roaster" was mostly used in drag racing wich it was designed for:
This intake manifold fits easily between the heads and valve covers.

The intake manifold used on NASCAR Hemi's is also a two piece bolt together design known as "Tub" or more commonly as "Bath Tub" and is not the same as the "Rat Roaster", this intake was a single carb intake manifold used in circle track and NASCAR competition and not in drag racing, it was made of magnesium and aluminum and this intake manifold is much wider than the "Rat Roaster" as the top goes out towards the valve covers, the lid has a depression where the carburetor sits and this intake was avaliable in a couple of versions, one for the 4150 series Holley and the other for the 4500 series Holley Dominator and nothing else.

Both the "Rat Roaster" and "Bath Tub" intake manifolds were designed and developed by the Chrysler Race Group and was for racing only.

Edited September 4, 2020 by Force

[Vietnam Vet67]

6 hours ago, Force said:

I feel we have to put some things straight regarding the intake manifolds.

The Hemi "Rat Roaster" is a two piece bolt together aluminum short ram intake manifold made and sold by Edelbrock and was available in a couple of versions, RR-1 inline dual 4-bbl's, RR-2 cross ram dual 4-bbl's and RR-3 single 4-bbl and the "Rat Roaster" was mostly used in drag racing wich it was designed for:
This intake manifold fits easily between the heads and valve covers.

The intake manifold used on NASCAR Hemi's is also a two piece bolt together design known as "Tub" or more commonly as "Bath Tub" and is not the same as the "Rat Roaster", this intake was a single carb intake manifold used in circle track and NASCAR competition and not in drag racing, it was made of magnesium and aluminum and this intake manifold is much wider than the "Rat Roaster" as the top goes out towards the valve covers, the lid has a depression where the carburetor sits and this intake was avaliable in a couple of versions, one for the 4150 series Holley and the other for the 4500 series Holley Dominator and nothing else.

Both the "Rat Roaster" and "Bath Tub" intake manifolds were designed and developed by the Chrysler Race Group and was for racing only.

Here is a picture of the Chrysler Race Engine Group taken in 1978. There were 2 dyno operators, 4 engineers and 3 engine builders. I am sitting on the bench second from the right. We did all Race engine development, Hemi and non-hemi, for NASCAR and NHRA drag racing. Also, couple pictures of me running one of the Race dynos doing Pro Stock engine development for Bob Glidden when he ran a Plymouth Arrow. The engine is a 288" destroked 340" engine which we ran to 10,000 RPM doing testing. The last picture in color was the Race Engine Group in 2001 when we got back into NASCAR racing. I am on the far left.