Voodoo vs thumpr

[Idaho]

The Thumpr cams take heat for supposedly sacrificing performance for the idle quality however I do know from chatting with Brian the Thumpr is not all about idle. It makes impressive power.

What surprises me is to hear the lope of the Lunati posted by bluNblu, and the XE linked by OldmanRick. No question, a choppy idle is sweet on the ears. In fact I willl confess, I would compromise performance (just a little) to have the mean idle. But after hearing those cams, I would base my choice strictly on performance. They sound plenty mean enough.

 

[Stewie1977]

Thanks Idaho I'm pretty much with the same thoughts now. They all sound pretty impressive. I was actually surprised at the XE275 as well. I imagine that it would be a little nicer for the street for cruising around the coast too & have even more vacum. Now I'm starting to get confused again lol.

 

[FrostyMopar]

I can also vouch for the thumpr series. I've had pretty good success with the smallest hyd flat tappet thumpr (227/241 on 107) in my 318. It made 352hp (flywheel) @5700rpm and 367tq at 4400.

good torque curve too with over 350tq (95% of peak) from 2800-5100. That's a nice curve by any standard.

 

[FrostyMopar]

again regarding headers for a VC.

a nice option would be to use a pre built flange plate with stubs like this.
http://www.summitracing.com/int/parts/hed-11205/overview/

And then a "flat" collector in 1-3/4" (like the hedman tight tube ones) sold from here
http://www.coneeng.com/collectors.html
(flat collectors are at the bottom of the page on the left)

And from there it will be relatively simple to build your own 1-3/4" block huggers that will fit a VC and will still make similar horsepower to a set of long tubes.


I plan to do this very thing soon for a non A-body project of mine where clearance is tight

something to think about.

 

[OldmanRick]

Since I mentioned overlap previously, instead of using the empty space between my ears, i decided to run those 3 cams thru the Wallace calculator to try and get a apples to apples comparison...

Here's what I got...

Thumper ... 73.5*
XE275hl .... 61*
Voodoo ..... 60*

I admit, the Voodoo surprised me a little.....I actually expected more. Designed by "Harold" i suppose.....nice.

 

[Stewie1977]

Thanks OldmanRick. So correct me if I'm wrong, but that shows that the Voodoo would be slightly better than the XE275HL for the street, as far as vacum is concerned at least, & that the Thumpr would have very little vacum or fuel economy ?

 

[OldmanRick]

Hi Stewie. From my further research, i think those two are about dead even as far as drivability is concerned.

Looking at those two, it comes down to the exhaust port flow/exhaust system? Since it sounds like your heads have some work done, and if it's free flowing, both will work equally well in my opinion, but if you feel that the exhaust port work, or exhaust system is restrictive in some way, the extra duration on that side of the Voodoo will probably be a advantage.

We're kinda splittin' hair's here for a streetable build, but I'd rule out the Thumper at this point, if it was me . As far as the other two, i'd have a hard time with it myself. Maybe some more post's with info can help us both decide...

 

[FrostyMopar]

Hi Stewie. From my further research, i think those two are about dead even as far as drivability is concerned.

if you feel that the exhaust port work, or exhaust system is restrictive in some way, the extra duration on that side of the Voodoo will probably be a advantage.

We're kinda splittin' hair's here for a streetable build, but I'd rule out the Thumper at this point, if it was me .

respectfully. why would you rule out the thumpr?

If you're looking for a camshaft to help get the best out of a restrictive exhaust system
the thumpr is my pick of the 3 as it has the largest spread between intake and exhaust duration by a decent margin.

Let's just recap here.

The Lunati is 234/242 @ 50, 513/533 lift & 110lsa
The Thumpr is 235/249 @ 50 .497/483 lift & 107lsa
The XEHL is 231/237 @ 50 .525/.525 lift & 110lsa

 

[Stewie1977]

Thanks again OldmanRick. After a little more research of my own I cam to the same conclusion. I think I'll probably go with the Voodoo. Have read a lot of good things about them & UDharrold. Seems like he really knows his stuff & has set the standard for others to follow. I also figure the extra on the exh side can't hurt either. Thanks to Frosty too for the advise on the headers. I told PP&R also make a set for the R-VC model & that they are really good but as yet I'm still to talk to someone who has a set & can tell me yay or nay. My wife gives me a weekly allowance to spend on the car so everything is happening slow & the more I spend the longer before it's on the road. $75 a week doesn't go very far lol.

 

[Stewie1977]

Good point Frosty. I didn't take into consideration what effect the huggers might have on the whole. In a perfect world maybe the Voodoo with the thumpr exh duration ? Or the thumpr with 110 LSA ?

 

[FrostyMopar]

It's always difficult to work to a tight budget. is the car in running, registered and driveable condition with the 318 engine?

If not I would highly recommend a two stage build. This means you can get her on the road first and then develop your performance from there.

1st stage. Get a running V8 in there and eliminate any issues with oil leaks and possible overheating problems. the standard radiator is not going to be sufficient for a worked motor even if you don't beat on it. tricked up motors are called "hot" for a reason lol!
I wouldn't recommend an aluminium radiator as they're nearly impossible to repair while brass can be made to last 50 years pretty easily.

Ideally you're gonna want a 727 torqueflite for a 390 stroker engine. I haven't done this conversion so I don't know exactly what's involved but i have been told that the tunnel needs massaging in a VC. There's probably a thread on this forum which is highly relevant to our Aussie cars in this regard.

A 904 can be made to take big horsepower but a stocker might let you down where as a stocker 727 is still a force to be reckoned with.

plus a tricked up auto will set you back a couple of grand and a 727 core starts from about $450.

I know someone in Victoria who specializes in 904's. he does very solid work and he is very reasonably priced but the distance might be a clincher for you.

(whatever you do, don't listen to any trans shop who says mopar transmissions are much the same as ford or chevy stuff. ask me how i know!)

once you have the "first stage" complete, the second stage can be whatever you want it to be.

 

[FrostyMopar]

Good point Frosty. I didn't take into consideration what effect the huggers might have on the whole. In a perfect world maybe the Voodoo with the thumpr exh duration ? Or the thumpr with 110 LSA ?

a cam of similar specifications to what you mention is entirely possible. but it would have to be a custom camshaft which is going to cost a little more if you get it off either one of those manufacturers.

If you're after a custom camshaft, it would definitely be worth giving all your available information about your engine/vehicle combination to your local reputable camshaft manufacturers. they will definitely want to know displacement, cylinder head flow CFM, compression ratio and vehicle weight as an absolute minimum before they can give you any recommendation at all.

A custom grind doesn't necessarily mean a better result than an off-the-shelf grind either. it's all about splitting hairs now!:burnout:

 

[OldmanRick]

Frosty, I don't have anything against the Thumper....... As you said, we are splitting hairs here . My opinion to rule out one of them is mainly because it has to be done at some point, and a final choice will have to be made.

 

[Stewie1977]

It's always difficult to work to a tight budget. is the car in running, registered and driveable condition with the 318 engine?

If not I would highly recommend a two stage build. This means you can get her on the road first and then develop your performance from there.

1st stage. Get a running V8 in there and eliminate any issues with oil leaks and possible overheating problems. the standard radiator is not going to be sufficient for a worked motor even if you don't beat on it. tricked up motors are called "hot" for a reason lol!
I wouldn't recommend an aluminium radiator as they're nearly impossible to repair while brass can be made to last 50 years pretty easily.

Ideally you're gonna want a 727 torqueflite for a 390 stroker engine. I haven't done this conversion so I don't know exactly what's involved but i have been told that the tunnel needs massaging in a VC. There's probably a thread on this forum which is highly relevant to our Aussie cars in this regard.

A 904 can be made to take big horsepower but a stocker might let you down where as a stocker 727 is still a force to be reckoned with.

plus a tricked up auto will set you back a couple of grand and a 727 core starts from about $450.

I know someone in Victoria who specializes in 904's. he does very solid work and he is very reasonably priced but the distance might be a clincher for you.

(whatever you do, don't listen to any trans shop who says mopar transmissions are much the same as ford or chevy stuff. ask me how i know!)

once you have the "first stage" complete, the second stage can be whatever you want it to be.

Sadly, I bought the car as rolling shell. I sort of bought it as rehab after I wrote my Fireblade off & the MRS had a dumby spit & said no more bikes. The car was completely stripped. So far I've got the body in primer, done a Disc brake front conversion, the BW78 is in & I'm planing a rack & pinion conversion for the steering. I should have the body painted in the next few weeks. I have a guy up here very well renowned for building race trans who is doing the 904 for me. He's had a lot of experience with them & is doing it for me for around $1000 with the manual VB, all new heavy clutch plates, bands, bushes & bearings. I was going to do it myself, but for that coin why would you bother ? I'm going for a pretty much stock look. Bench seat, white walls & hubcaps. That's part of the reason why I want it to sound a little wild, that's going to be the wow factor. Who expects a stock looking Regal to sound like a drag car ?

 

[FrostyMopar]

sounds like a really cool project. the rack and pinion should create more room for possible exhaust/header options and also eliminate the problem VC's have with the steering box being so close to the V8's cast-in oil filter boss/sandwich plate.

$1000 is crazy cheap for a reco/tricked up auto build. I hope he's as good as you say.

It's very important that whenever you farm out work on your mopar, the person you're trusting your car/parts to is familiar and experienced with mopar parts. too many reputable "chevy oriented" shops out here think they know everything but just have no idea about our old girls. It can lead to costly mistakes.

It really leaves a bitter taste in your mouth when you decide to pay a professional to have a job done then have to pay someone else 2x that much to fix it right. plus there's your own spanner time you've wasted!

The sleeper look is very cool, The fastest car i've ever been in was a gentleman's VC. it was a sleeper through and through except for the rough idle. I was up at chryslers on the murray a few years back and i asked him about his camshaft. he said he didn't remember the specs of it but he opened the bonnet. It had a set of VE-CM pacemaker extractors that were modified to fit, i was amazed. i must have sounded like a bratty kid asking him all these annoying questions but he mustn't have been bothered because he offered to take me for a spin. I didn't need to be asked twice!

It was a 360 with J heads, a big solid cam and a 5000 stall with 4.11 gears. and when he planted the foot at launch it was like being shot out of a cannon as far as i could tell.
He told me it ran 11.6 on the strip with drag radials and said "it's pretty slow on street tires" and i just thought "slow? are you mad?" Fun times indeed!!

If you have facebook there's a few Aussie valiant groups on there that are useful for classifieds/trading, they tend to be cheaper than ebay etc because there's no fees involved. if you get stuck at some point a lot of people are very willing to offer advice/assistance to help your project along with minimal fuss too.

It's a good time to be building a mopar!

 

[fishy68]

respectfully. why would you rule out the thumpr?

If you're looking for a camshaft to help get the best out of a restrictive exhaust system
the thumpr is my pick of the 3 as it has the largest spread between intake and exhaust duration by a decent margin.

Let's just recap here.

The Lunati is 234/242 @ 50, 513/533 lift & 110lsa
The Thumpr is 235/249 @ 50 .497/483 lift & 107lsa
The XEHL is 231/237 @ 50 .525/.525 lift & 110lsa

Respectfully, that's true it has more duration on the exhaust which could help if the exhaust system was poor but it also has 13.5* more overlap which generally hurts performance. I'm with all those that agree it's a pretty close call with either but I'd give the performance edge to either the Lunati or the XE275HL. JMHO

 

[Stewie1977]

sounds like a really cool project. the rack and pinion should create more room for possible exhaust/header options and also eliminate the problem VC's have with the steering box being so close to the V8's cast-in oil filter boss/sandwich plate.

$1000 is crazy cheap for a reco/tricked up auto build. I hope he's as good as you say.

It's very important that whenever you farm out work on your mopar, the person you're trusting your car/parts to is familiar and experienced with mopar parts. too many reputable "chevy oriented" shops out here think they know everything but just have no idea about our old girls. It can lead to costly mistakes.

It really leaves a bitter taste in your mouth when you decide to pay a professional to have a job done then have to pay someone else 2x that much to fix it right. plus there's your own spanner time you've wasted!

The sleeper look is very cool, The fastest car i've ever been in was a gentleman's VC. it was a sleeper through and through except for the rough idle. I was up at chryslers on the murray a few years back and i asked him about his camshaft. he said he didn't remember the specs of it but he opened the bonnet. It had a set of VE-CM pacemaker extractors that were modified to fit, i was amazed. i must have sounded like a bratty kid asking him all these annoying questions but he mustn't have been bothered because he offered to take me for a spin. I didn't need to be asked twice!

It was a 360 with J heads, a big solid cam and a 5000 stall with 4.11 gears. and when he planted the foot at launch it was like being shot out of a cannon as far as i could tell.
He told me it ran 11.6 on the strip with drag radials and said "it's pretty slow on street tires" and i just thought "slow? are you mad?" Fun times indeed!!

If you have facebook there's a few Aussie valiant groups on there that are useful for classifieds/trading, they tend to be cheaper than ebay etc because there's no fees involved. if you get stuck at some point a lot of people are very willing to offer advice/assistance to help your project along with minimal fuss too.

It's a good time to be building a mopar!

I'm hearing you with the "it's the same as a chev or ford" rubbish here. This guy has built race trans for over 40 years & has a real good rep up here. Told me straight up what I need to buy & what the weak points are & how to fix them. I'm buying the parts & he's building it for me for $400 labour. He's retired & a real old school hot Rodder who just does a bit on the side now for beer money. I know a lot of guys in the hot rod scene up here, really good guys & they put me onto him. I think I'm onto almost all the mopar sites on Facebook & few chrysler forums too. Some of the guys are a real wealth of knowledge.
Sounds like the one you went in is pretty much what I've got planned, just not quiet that extreme. I want to be able to drive past the cops & not get a 2nd look. I've got onto a really good engineer up here, also through the hot rod guts, & I'm in consultation with him at every step. If I ever get pulled over, which is certain up here in the nanny state, I can stand back & say to dour worst lol. Everything is 100% above board. Maybe the next build will be a little more animal. A 38 dodge rat rod with a 392 hemi & mechanical injection ? Well, I need to finish this one & still be married before I think about that lol.

 

[Stewie1977]

Well I made my decision. Had to toss a coin at the end really, but I've decided to go with the lunati. Now only another 18 months or so before it's running lol. Thanks to everyone for your input. I really appreciate you guys taking the time to help me make my decision. Especially all you guys who ran the computer sims & posted the videos of the sounds. I really hadn't thought about the XE275HL till I heard that & after the thumpr didn't seem like the only angry cam that would compete with the Voodoo. I've also learnt a hell of lot more to look at when it comes to cams & everything either side of it. Thanks again everyone

 

[Idaho]

Now you owe us a burn out video.
:burnout::burnout::burnout::burnout::burnout:

 

[FrostyMopar]

good stuff mate, i'm sure it will go like a cut snake!