Like it say's has anyone ever broken the 8 second barrier yet? I know guys are running in the 8's with small cubes with either w8's or w9 heads and r3 blocks!

Slightly off topic, but; how small in cubic inch on the W8/W9?

Hopefully I will be able to answer that soon. I have 358 R5P7.

I think with the powerglide it will be really hard. Have been comparing dyno sheets. The engine I bought was oversold a little. I am going to lose 30 lbs of torque. Gain 5 HP with Q16. That is if the extra compression does not help. I really think the extra 1.2 in compression should pick up the torque to over 600 lbs.

My old W8 421 ran 8.90 and had over 880 HP from 8,000- 9,000. On paper it should have really carried the mail. The car MPH'ed really well but would not 60 or 330 with the powerglide with any gear ratio and several converters. It was kind of nutty. It would not leave but 20 ft out tried to blow the tires off. Had to take 2-3 degrees out around the 7600-7,900 RPM range in low gear to keep things in control. For the most part just think their was a serious problem with the combination.

An engine with that power should run 8.5's in my car. So we will see what the R5P7 does. Just not extremely optimistic.

Leon

Leon,
I remember when Tim Davis built the motor for the blue barracuda that used to run NSCA "Real Street". I remember him telling me that the motor made more HP the his "Hot Street" daytona. But the barracuda would never really run the number in real street. Those guys tried gear after gear, converter after converter, cam after cam. That 360" motor would just flat out never run with the bigger inch motors.

Sounds like a lot of storys I hear with the R5/P7 motors. Just not enough cubic inch to make the torque no matter how much gear/converter you put in a middle weight car.

Has anyone put a Liberty behind one of these yet to use the powerband to its true potential, like a baby pro stock car, yet?

Guys,
Take this for what it's worth, but my experience with these motors is very similar to how high torque BB "bracket" cars (typically dragsters) are set up. I'm refering to how they tighten up the convertor to leave "soft" hence not hitting the tire too hard. Then out 30' its really digging in and and comes on like a freight train.

Now, with the 358, you need to have a loose convertor ~7500. Trust me, any tighter and the performance falls off by tenths. Been there, done it. Once figured out, the convertor only lasted ~85 passes and needed a rebuild. It also wasn't the most efficient, but made the car perform the best. Talking on the order of 10% slippage, but boy could it repeat itself. Where I'm going with this is, you can't go after the "hit" trying to get all the torque you can to move your car. Let it come to the car by 20', it will help with 60' times on a little tire and the HP will get you rolling.

Once last thing, it you have the original ring pack 1.5mm or .031" in it, with .007-8" piston to wall clearance, you gotta run it hot! I can't stress that enough. If you run it cold <180F, you'll loose a tenth again. Ask me how I know.

Good luck, they're great to race with and the technology is just cool.

Regards,
Mike

Tim didn't seem to have an issue with his Daytona running. In Hot Street there was a 2800 minimum. I just can't see 150 lbs. making that much difference. My issues were with the 60 and 330 times. Otherwise the incrementals were respectful. Bill's car was just over 3,000 and ran a torqueflite. Chris ran a similar combination with his green barracuda with a torqueflite and just could not get around these issues either. Like I say can't see 150-200 lbs making the difference. Tim had something else going on besides a sleeker lighter car. Pro Trans anyone with an A-1 converter. Palini ran great with one of these engines too with weight. Tim's brother Mike ran well with the Demon and a powerglide and had less head than any of the others mentioned, Tim's words not mine. But, he ran 8.80's with more weight, less tire and a powerglide. So it can be done. Just got to get the combination right. I suspect my 7" converter was similar to what Mike ran as Tim recommended it. My car just tore the things up.

I think the small tire is a freind to these engines in heavier cars. My problems were weight, two speed tranny, too much tire. Something has to give. Some wheel speed, more gear ratio's to stay in powerband, less weight to not bogg on the converter.

Like I posted my old W8 was making 880 HP at 7,800 and that is were the car started spinning. But, put bite in the car and it would hook too quick. This P7 only makes 850 at 7,800 and brings the power in more gently. This should allow me to take bite out of the car and still not blow the tires 30 ft out. Although the converter guys would never agree I really think a 6,500 converter will work better when running a glide. I ran one with the W8 and the car was faster in the short times. But, everyone thought that was the wrong way to go and I listened. The converter I have now stalled 7,200 with the W8 and this R5P7 engine will make far less torque at that RPM so the converter should stall less. Just how much, don't know. But, I am planning to try it first.

Leon

I think 8's are ultra possible.
I have already seen one go 9.40 at 142+ in a 2950 pound car.
This with a tiny cam and 12 to 1 compression. By tiny cam,248@50 lol
Used a 904 tranny, reworked 8 inch convertor and was able to dip into the high 1.2xx 60 foots.Think he shifted it under 8k.
Car really seemed to get with it in second gear.Had a 950 carb on it
With the big head, i think a three speed tranny is a huge plus at 358 inches.

Gotta think bigger cam and more compression should get in 8's pretty easily with a 3 speed, based on what i have seen.

With all the new 5-8 speed auto tramsmissions out there. Why not work off on of those platforms. The the Challenger, Corvette and Mustang multi speed autos seem to be fairly durable. 6000 stall and closer gear ratios might work.

Mopartony,
When I first put the car together, I put the motor in it just as it came off the dyno at EEI. Obviously, I had to disassemble the front half of the motor and machine/make everything to fit in the frame rails, but other than that, internals remained untouched and legal for Nascar. This one is a roller combo with only .730 lift and 245 @ .050. Certainly nothing BIG in drag race terms. I also ran the cast intake and used a toilet (injection). Motor made more hp on gas, but I prefer the injection (just preference).
When I first started, it left like a beast, because it was real fat. By beast, I mean 1.05 60' @ 1650lbs and only 358in and 12:1 comp. But the car didn't mph well.....162mph. Anyway, after pulling tons and tons and tons (can't emphasize this enough) of fuel away, walla, it came to life. Same combo picked up .5sec, yes 1/2 a second in et and 9+mph in the quarter. Best investment you can make is an O2 in both sides of the motor 12" down from the head. The tune was set for 90deg weather in eastern PA (humid) and ran 7.70 all summer. When everyone else dropped off tenths in the summer heat, we didn't loose .01. These motors are super efficient, and not meant to mix and match parts. I do have the first Bullet cam made for these motors, that I may try this coming year, but if it doesn't improve performance by .2 or more, I'm going back to the smaller roundy round cam........no wear and tear....they last forever.
If you want to mix and match, I suggest you get some raw heads (they're cheap ~$300) and send them to Slawko or Patterson and build it from the ground up. If your intent is to take a nascar motor and change this and that and expect an additional 100+hp, that's wishful thinking. It may show that 100+ on the dyno, but it won't on the track. Just my $.02

Best speed secret out there: It doesn't take all that hp to win, you just need the rest of the combo to perform equally up to snuff. I'll leave with this question: When's the last time you pushed your car around? Can you push it with one hand or finger? There are tenths to be gained with rolling resistance.

Mike

Don, I hear what your saying in regards to the P7 deal you are talking about. However 9.40 is a LONG way from 8.99. Believe me. However I dont see why it could not be done.

in fact I am sure it can be done, I am sure it has already been done. In the PSCA class I run Hot Street it has a very large presence of these old nascar pieces. Unfortunately they are Ford and Chevy ones. Also most are a tad larger than 358, generally in the 390" range. Those cars are runniing 8.40's to 8.20's but are liteweights coming in at 2600-2700lbs. We have been discussing, as racers of maybe going to a cup based engine all around. Meaning everyone will ahve ti run these type of motors. Of course the Chevy guys are the ones leading that pursuit, as they are the fast cars. But I am not opposed to the idea. My problem is the lack of developement for the Moapr cup stuff in drag racing. I know the 2.2's are making 1000-1050 hp but they have reat support to make them drag rac friendly. I hear MBE is doing Mopar stuff but have never contacted them about goign this route. But I am certainly intrigued and interested.

Al

The motor I am referring to also had the liabilities of not using an electric water pump, and used straight 2 inch W2 headers that perhaps weren't optimal.. not sure what was left on the table there?
Like to see what a good dominator would have done as well on it, definitely likely some 20's in that with some tweaks.

The combo was ran with the small plenum edelbroc intake from Nascar. They tried the M&M and it did not run as well. I have a large plenum edelbroc I may try but, the powerglide will probably like the small one better.

Mike,

Thanks for the info. I will be adding this thread to my favorites so I can come back to it.

The class I am building for requires 2 4bbls. So I need to run the M&M or a sheet metal intake. I am prefering the M&M over the sheet metal for costs vs gains.

The engine builder said 100hp with upping the compression, 2 4bbls(new Holley Dominators) and a new cam. I can only hope.

The car really only needs to run in the 8.30-8.40 range as it is a 8.50 index. But if it is faster I will not complain.

As for the car rolling with one hand or one finger, no idea. The parts are being delivered to the chassis shop for the build and the body and other parts I have will be dropped in mid January.