Hey guys looking to put together a mopar combo to run ultra/ultimate. I think my best bet would be a 540 b1 combo on nitrous. It looks like the car would have to weigh 3250. Is there any way someone could give be an idea of the horse power neaded to be competetive in this class and run 4.90 to 5.0 in the 8th mile? A all out na b1 motor can make 1100+ so I figure if it's built for a big single stage of nos if I can make 850-900 on motor than hit it with a big single stage plate kit that would put me in the ballpark to not just be a class filler but actually be able to be competetive. Anyone out there that can give some info or tips would be much appreciated thanks in advance. Combo would be going in my 67 barracuda notch back.

Does 1400hp sound about right to go 4.90 in the eighth mile? Could a 540ci B1/mc motor make 850-900 HP NA and still be able to be set up to take a 500hp hit of nitrous?

"Your Flywheel HP is 1,364
computed from your vehicle weight of 3250 pounds and ET of 4.9 seconds."

That is according to Wallace calculators.

I have a fogger with that combo. (B1 org.)
Mine made 875 on nut and I think there was a little left on the table.
I plan on shooting 5 to 600 on mine.
My car is at 3210 now.
Was thinking about going with a new intake and plate to run some ultra also.

My 588 B1 makes 1050 n/a and we race a 275 limited jet class that only allows a .036 fogger jet which is 300-350hp....With this setup we've been 4.90 @ 141mph weighing 3250# !!

Gonna have to be spot on with shocks,trans & rear gear,converter along with the tune-up !!

Went 5.20's on a plate with my lowdeck -1 and it makes 895hp and that was 6 yrs ago long before the 275 drag radial pro !!

Not to hi Jack the post but what was the low deck combo if you don't mind me asking

saw this over on YB from 2014:

"Re: MOPAR B1 COMBOS

--------------------------------------------------------------------------------

we ran a b1 original headed 540 in my leaf spring 275 dart at 3300lb and best was 5.07@140mph

I don't know of anyone else that has sprayed more on a b1 original than we did, 48 jet, reliable engine but camshaft very tricky, really didn't respond much above a 40 jet"

Thanks for the replies sound like this combo could get it done in ultra

This would be the best combo for ultra currently for a Mopar I think. But you are going to need good heads, a really good cam guy and nitrous tunes spot on.

Might want to talk w/ Tom Hemphill. He did a big B1 nitrous motor for a friend and that thing ran STRONG. Was a single carb, cast manifold deal w/ 2 stages, but even on one big gun it's doable.

My Demon ran 5.0/150 when Mike was racing it, or so I was told. It had a 4.500 bore x 3.85 stroke 499 KB/B1 with relocated 2.44 intakes, 1.90 ex and huge ports. Had a fogger and a 300 HP plate, not sure which he was hitting first but the 2nd stage came on with a timer to coincide with the wheels coming down. Adger Smith said it was making 1250 HP and the car weighed 3250 with me in it. They had the heads milled to 47cc and with flattop pistons and o-rings, it was about 16-1.

I got a 6.32 / 111 on the motor at 3250 if that gives you any idea. I need it to go 5.0 @ 150 on 315 DRs to be competitive locally here in KOS, and be able to still drive it on the backroads.

If allowed, go bigger than 540CI. In my opinion.

B1MC Heads on a 572CI and a large single hit of Nitrous would be mean.

Actually simple if Gary Robbins tells you what you need and your not cheap it can be done.
No mopar specialist needed like some will say.

Jake Gier has been very fast on his 26x8.5 tires with one stage and dinosaur Fred Brewer heads. Believe he's been 4.80's with it. I can't remember the cubic inch.
Gary's combo and his old one are really effective also, I'm tempted to bother him and learn more about his old -1 combo.

Fishy340 has a nasty 4.30 small block he won't tell us about lol hey Andy

Who could possibly be stupid enough to try run a Mopar in a heads up class. Oops I am that stupid.

As others have said, the proper cylinder head work and camshaft is a CRITICAL choice. The problem with Mopar cams is the fact that you can NOT in any way shape or form, get the numbers you NEED on available cam cores. So that means a custom billet core cam. That's a $1500 camshaft and most balk at that and then wonder why the stuff won't run or is timing sensitive with big loads of nitrous.

But you might be in luck........LOL!!! I just ground Jake Gier a new billet core 55mm cam for heavy nitrous use. Fed Ex lost the cam, so I had to get another one started.......THEN they found the cam and now obviously won't pay the insurance claim. The new cam is likely far enough along that I will be stuck with it. So I will likely have a billet core 55mm nitrous cam in stock and on the shelf. But as I said, they are not cheap

Gary, and Scott FTW...Yeah what they said lol




Ray

bumping this up for.....

last season I went 5.10 @ 140 with very little testing.

last year I was 3300, this year I can be 3050 with a single entry plate (which I am using) and the Hoosier 275.

Gary has been fast at a heavier weight than Ultra (3200+) but he has a bigger motor than allowed, ultra for mopar is limited to 540 with a power adder. As of now, I don't know of any Ultra Street legal Mopar that has been in the 4's , and by that I mean

540 or less and a plate nitrous kit. That's what got John Sears to lower the weight for this year.

Well what does an NA mopar have to weigh to run that class??

Hoosier 275……………is that making a comeback or just what you decided to use ?

Are the rules for Ultra always set up to keep the cubes at a limit for Mopars ?

Mike