[Sonic Blue 85]

From everything I have heard lately going to anything over 13 compression does not gain anything. This info is coming from some of the best engine builders around. So what size engine was it before it came apart and what numbers did you get out of it? Also what happend to it anyway? I meant to ask you about your car, I have a video of the last run at the Pinks event when we got lined up against each other. The first time I saw the video I thought that there was something wrong with my car. After watching it a few more times I concluded the exhaust noise that you can hear in the video is your car. I am gessing you do not have mufflers, my car has an X pipe and mufflers. The car that can be heard in the video sounds like it has a lot of cam and is out of tune or has something wrong with it, or the video is distorting the sound. I have been curious if the sound was distorted or if there was something wrong with your car.
From the sound of things, if we ever get lined up against each other again, I will be seeing tail lights pull away rather quickly. I don't plan on stepping my car up to that level for a while, if ever. Good luck.

[thesource]

I would also lean toward less compression and maybe more cubic inches if you plan to run low 9's NA . As said before though , its not going to be cheap . The quality of parts goes way up . The catagory of cylinder heads alone are easily $1000-$3000 over what you probably currently have . Going nitrous will be cheaper on the pocket book and easier to run the number you are looking for within reason . There are several people runnin high 8's with nothing more than a 408-427W and a 250-350 shot of nitrous . Some are doing it with less nitrous than that .

If I were going to look to running those kind of times , I would seriously consider going with a second hand turbo that came off of a big car from last year or two years ago . Angel from Auto Specialites ran 7.90's with a 302 cubic inch engine and a turbo in his red car .

[1SLO85]

Originally Posted by Sonic Blue 85

From everything I have heard lately going to anything over 13 compression does not gain anything. This info is coming from some of the best engine builders around. So what size engine was it before it came apart and what numbers did you get out of it? Also what happend to it anyway? I meant to ask you about your car, I have a video of the last run at the Pinks event when we got lined up against each other. The first time I saw the video I thought that there was something wrong with my car. After watching it a few more times I concluded the exhaust noise that you can hear in the video is your car. I am gessing you do not have mufflers, my car has an X pipe and mufflers. The car that can be heard in the video sounds like it has a lot of cam and is out of tune or has something wrong with it, or the video is distorting the sound. I have been curious if the sound was distorted or if there was something wrong with your car.
From the sound of things, if we ever get lined up against each other again, I will be seeing tail lights pull away rather quickly. I don't plan on stepping my car up to that level for a while, if ever. Good luck.

The motor was a 408 and it was running fine at Pinks. I am running 1 chamber Flows with 3.5" pipe fron the headers all the way back. As far as what let go in the motor....a bearing froze on the rod to the crank, then broke the rod. Oh and as far as numbers...the old set up made 679HP and 572tq.

[1SLO85]

Originally Posted by thesource

I would also lean toward less compression and maybe more cubic inches if you plan to run low 9's NA . As said before though , its not going to be cheap . The quality of parts goes way up . The catagory of cylinder heads alone are easily $1000-$3000 over what you probably currently have . Going nitrous will be cheaper on the pocket book and easier to run the number you are looking for within reason . There are several people runnin high 8's with nothing more than a 408-427W and a 250-350 shot of nitrous . Some are doing it with less nitrous than that .

If I were going to look to running those kind of times , I would seriously consider going with a second hand turbo that came off of a big car from last year or two years ago . Angel from Auto Specialites ran 7.90's with a 302 cubic inch engine and a turbo in his red car .

Ya think I don't have good enough heads? They are AFR 205's that have been highly ported and polished. The machinist that's doing the machine work build and machines for 4 Pro Stock teams, lots of True 10.5 teams, etc and he said the porting done on my heads was very impressive.

BTW, my heads were done by Lingenfelter.

[thesource]

I'm not saying your heads aren't good . But there is a huge difference between a ported AFR 205 and a Yates or Victor style head . An AFR 205 will not run low 9's NA unless your car is super light weight , thats a fact . If you compare your head to the heads required to run the number you were planning on running , yes you will need an additional $1000-$1500 on top of what you have invested in your AFR's .

[1SLO85]

Originally Posted by thesource

I'm not saying your heads aren't good . But there is a huge difference between a ported AFR 205 and a Yates or Victor style head . An AFR 205 will not run low 9's NA unless your car is super light weight , thats a fact . If you compare your head to the heads required to run the number you were planning on running , yes you will need an additional $1000-$1500 on top of what you have invested in your AFR's .

Gotcha

[thesource]

What do your heads flow by the way ? I didn't know Lingenfelter did anything with the AFR's .

[1SLO85]

Originally Posted by thesource

What do your heads flow by the way ? I didn't know Lingenfelter did anything with the AFR's .

It was a special favor to the engine builder. Here are the before and after flow #'s on the heads.

Intake before-200/123 Intake after-200/148
300/181 300/214
400/235 400/257
500/275 500/294
550/287 550/304
600/294 600/311
650/300 650/315
700/278 700/317.5
750/278 750/317.5

Exhaust before-200/98 Exhaust after-200/110.5
300/142 300/158
400/170 400/193
500/183 500/209
550/187 550/212
600/189 600/215
650/189 650/216
700/189 700/217
750/189 750/217

[thesource]

From what I understand , the rule of thumb is to double your max air flow number and thats a pretty close estimate of what a head will do in a NA application . In your case , the best flowed 317.5 which should have been good for about 635-640 in an ideal situation . Cubic inches are not part of the equation as they only determine how high you need to spin it to make that number . So if your old setup went 679 NA , I'd say those heads were pretty much maxed out and then some .

[1SLO85]

Originally Posted by thesource

From what I understand , the rule of thumb is to double your max air flow number and thats a pretty close estimate of what a head will do in a NA application . In your case , the best flowed 317.5 which should have been good for about 635-640 in an ideal situation . Cubic inches are not part of the equation as they only determine how high you need to spin it to make that number . So if your old setup went 679 NA , I'd say those heads were pretty much maxed out and then some .

So whatcha think...maybe start looking at some AFR 225's?

[thesource]

Originally Posted by 1SLO85

So whatcha think...maybe start looking at some AFR 225's?

I don't think 225's will get you low 9's NA either . I would look at some fully done Highports (240cc range) or even larger than that . I would think you will need a head that flows 350+ on the intake and 260+ on the exhaust to make the power NA you are looking for .

Take a look at Hamiltons combo , it runs 9.50s and has a big ass head on it . You want to run another half second faster than that . You are easily talking another 50-75 hp over what he has .

[1SLO85]

I am wanting 9.6-9.8's N/A and high 8's on the dope.

[thesource]

I know Ralphs car runs a Yates head on it and goes 9.90's all motor . Hamiltons engine runs a Yates head and runs 9.50s . I am not sure what either car weighs but I know they spin them pretty high rpms .

You should be able to run mid 9's with a big high port but it sure in the heck won't be some off the shelf job or done by a friend of a friend deal . With a high compression 408-418 cubic inch , you will still need to spin it 7000+ rpms to reach your goal NA . I would look into a custom solid roller from either F.T.I or C.I. to help you reach your target .

Check out TEA or Fox Lake to get an idea of the money you are looking at spending . Then add in shaft mount rocker arms and 3/8 custom pushrods pls a custom roller cam . Its going to get pretty expensive pretty quick .

[1SLO85]

Originally Posted by thesource

I know Ralphs car runs a Yates head on it and goes 9.90's all motor . Hamiltons engine runs a Yates head and runs 9.50s . I am not sure what either car weighs but I know they spin them pretty high rpms .

You should be able to run mid 9's with a big high port but it sure in the heck won't be some off the shelf job or done by a friend of a friend deal . With a high compression 408-418 cubic inch , you will still need to spin it 7000+ rpms to reach your goal NA . I would look into a custom solid roller from either F.T.I or C.I. to help you reach your target .

My car weighs 2740 with me in per SAR. In reference to the bolded line above...are ya talking about a solid roller cam? If so, I have a custom grind from Cam Motion.

[thesource]

Originally Posted by 1SLO85

My car weighs 2740 with me in per SAR. In reference to the bolded line above...are ya talking about a solid roller cam? If so, I have a custom grind from Cam Motion.

You have a custom grind for your old combo . Once you start changing things , the cam no longer is of much use for the new combo .

If your car weighs 2740 with you in it , then you were putting down about 540 rwhp on a 10.0 pass . You will an additional 35 rwhp to go 9.80's on a perfect pass and 72 rwhp to run 9.60's on a perfect pass . That sounds simple enough but you'd be surprised at how much you will have to change to get that power .

One thing you have going for you is your car is pretty light so it will take less power to get it down the track . I have about 240 lbs extra on my set up .

[thesource]

Also at your weight , on a perfect 8.80 pass you will need 794 rwhp .

[1SLO85]

Originally Posted by thesource

Also at your weight , on a perfect 8.80 pass you will need 794 rwhp .

I know the C4 sucks alot of my HP. The 679HP number was on a motor dyno. I plan on spraying around a 200 shot to start. So, ya think my cam is worthless just because I will be running different pistons?

[thesource]

Originally Posted by 1SLO85

I know the C4 sucks alot of my HP. The 679HP number was on a motor dyno. I plan on spraying around a 200 shot to start. So, ya think my cam is worthless just because I will be running different pistons?

No but different pistons alone will not increase your engines power enough to amount to much if anything . Another thing is unless the cam is designed for nitrous use , your gains will probably be less than the advertised shot of nitrous you are spraying . Here is some quick math for you .

679 - 540 = 139 hp (about 20% loss through the drivetrain)

35 x 1.2 = 42 fwhp increase to run 9.80's
72 x 1.2 = 86.4 fwhp increase to run 9.60's
794 x 1.2 = 952.8 fwhp to run 8.80's

[1SLO85]

Originally Posted by thesource

No but different pistons alone will not increase your engines power enough to amount to much if anything . Another thing is unless the cam is designed for nitrous use , your gains will probably be less than the advertised shot of nitrous you are spraying . Here is some quick math for you .

679 - 540 = 139 hp (about 20% loss through the drivetrain)

35 x 1.2 = 42 fwhp increase to run 9.80's
72 x 1.2 = 86.4 fwhp increase to run 9.60's
794 x 1.2 = 952.8 fwhp to run 8.80's

Good info. I didn't think about the N2O and cam. How can I tell if my existing cam would be good for the juice?

[thesource]

I am by far not a cam expert . You would need to show the actual specs to someone that is and see what they think . I'm not saying your cam will not physically work on nitrous , it just probably will not give you the results you are looking for .