My current setup is LS2 w/heads, cam, FAST102, headers, etc. Car dyno'd in the 480s previously. My current cam has 9 degrees of overlap, but I am replacing it with a Cam Motion PD (224/238-118+4) (595"/.587") which has -1 degrees of overlap - thanks @old motorhead for the Cam Motion tip. I am looking forward to losing the sewing machine action I have going on with my current valve train and having much improved street manners.

The cog overdrive can add 3.5 psi. Will my heads, headers, and cam increase efficiency enough to offset that 3.5 psi to keep me under 10 psi? I could convert e85 later on, but I want to tune on 93 for now and remain within safe limits.

Thoughts?

 

Probably need a 3.7 or 3.8 front pulley to stay under 10psi. NO WAY you'll stay under 600 rwhp though

You could do the same thing by reversing the rear pulleys you have now. They are more than likely a 3.0" driving a 3.49". Reverse the position of those pulleys and you have about the same drive ratio as the cogged o/d pulleys.

 

Need to back this up, since what TVS are you going with.
The Edelbrock does not have the best of internal passage cooling, so one of the reasons that you want to run a meth kit with from the start.
Which brings up the second part, since you are running a meth kit to keep the blower from being a heat pump, the other half of meth fluid is meth, which allows you to push the boost on stock fuel.

On a stock LS9 with meth kit, not a problem pushing the boost to over 22lbs. As for LS2, is the motor build for this kind of boost in the pistons and rods, as well as the compression lowed on the motor as well. The stock LS crank can take 1K HP thrown it without problems.

As for the heartbeat blower, would need to swap out to LS3 heads to get it to work, does have better internal cooling, but would still run a meth kit with it as well.


As for meth fluid, it just distilled water and Methamphetamine that is mixed 50/50. Walmart has distilled water on the cheap, and if you check for a local chemical supply company, can get meth in the 5 gallon containers for around $8 a gallon, If you are buying premix meth mix, its the shipping that is going to eat you alive that jacks the price up to the $50 a gallon over the standard mark up of it alone.

 

The only reason that I am cogging the rear drive is to get the classic SC whine. Silly I know, but at least I am honest

I know people change the front pulley to make up for the efficiency of the heads/headers, so I thought that doing the OD on the rears might kill two birds with one stone. I guess that isn't going to be feasible due to the amount of boost gained on the rear. For now, I will just do a 1:1 cog and change the front pulley as required. I don't want to be on the bleeding edge of safety with 93 where one bad tank of fuel could result in disaster. I figured the car will be around 630-650 rwhp, which is more than enough for my needs. With that said, I did go with a triple disc since I was potentially going to be cutting it close on the twin disc Monster organic. Monster advised to go triple "just in case". With that said, I still want to hold to my original power goals.

I purchased the standard TVS2300, not the Edelbrock Heartbeat style blower. I want to avoid meth if at all possible due to issues that I had previously. If I need more octane, I will convert the fuel system to E85. I dealt with clogged nozzles and solenoid failures years ago when I had a Toyota Supra. It was a constant headache back then. Granted things are probably better now, but I am a once bitte, twice shy guy. I think the kit I ran back then was from Snow Performance, but that was over 12+ years ago. Back in the day, running meth was dodgy at best with all the piggyback ECUs and controllers that were needed on the Supra platform.

E85 is pretty much at every other gas station in a 350-mile radius, so meth doesn't make a lot of sense in my use case. My new fuel pump is rated for E85, but I would still need to add a supplemental pump and larger injectors for the increased flow. I am trying to avoid that as one thing then leads to another which leads to another and then you have a horsepower monster that is not much fun to drive anymore. I found out the hard way that there is a fine line between a fun streetcar and a high-powered headache. I am going to avoid the later at all costs this time around. I know it's a slippery slope, so I am putting up some hard boundaries to keep myself in check. For now, that barrier is safe boost limits on 93 octane. Bottom end and compression are all stock on the LS2. If it lets go, I will do a forged short block, but I would like to forgo that for the time being. I am very hesitant to upgrade the fuel, build the rotating assembly, and start turning up the wick up on the blower. I know where that leads

 

Can't fault you for wanting to get a little whiney. Never owned that set up but have heard a few and they sound pretty bad ***.

So, a 3.2" front pulley with direct drive (1:1) cogged rears is similar to a 3.8" front pulley with overdriven cogs in the rear. Basically, same blower speed. That will get you mid 600's rwhp and probably show 9ish psi. Been there done that twice. With the bigger front pulley and o/d rears, you virtually eliminate belt slip as an issue. And you have room to spin the blower even faster should you desire to. Once you get much under 3.2" pulley size and over 10psi, you really have to fight belt slip. If you're buying cogged pulleys, the smart play to buy the o/d pulley set.....even if you never go smaller than a 3.8" pulley. If you ever tire of the whine, you can put your stock o/d pulleys back on and little will change other than it being quieter with just slighly less boost/power. The cogs are a 1.2 o/d ratio vs the pulleys you have now being 1.16 o/d ratio.

Yeah, don't fool with the methamphetamine. That **** will rot your teeth. With E, you get extra octane and a definite cooling effect. Magnuson claims you get 1% more power for every 10* you can lower intake air temps. E lowers you intake air temp as it's going into the cylinder head. No way to measure that, but it's obviously there. If you're flex fuel tuned, your tune will will give you some protection from a bad tank of fuel.

 

PD blowers love having Methanol sprayed through them. My old setup was a Maggie TVS 2300 with the 10 rib LPE front drive and 50 MM rear cogged drive. Its still sitting on a shelf in my shop. Car made 130 HP more on meth and made #'s a TVS 2300 should not make. Yes methanol like Nitrous is dangerous if you are not diligent. A great trick is to use a wideband that has a 0 to 5V output to trigger a LNC 2000 to pull timing if the the car goes lean due to a pump failure. You can also relocate the IAT sensor and use it to do the same. Meth is only bad for the lazy. Just my humble opinion.

 

Interesting. I've had meth on one TVS2300, half meth/half water on another, and no meth on a third. In my case, the straight meth was worth 22 rwhp. That was dynoed before and after meth install and tune on the same day on the same dyno. Done by one of the better tuners in the Houston area.

I wasn't spinning it real hard and that may be the difference between your experience and mine. My blower was spinning at 13,600 rpm at 6000 engine RPM on an LS3 with SBE and mild blower cam + bolt ons. 3.2" blower pulley on a Heartbeat TVS2300. About 9.5 psi and 664 rwhp on meth. 642 sans meth. Not worth the hassle to me.

Just curious what your drive setup was. Under, over, or direct on the rear pulleys? Also, what size front pulley? Not arguing with your results. Just looking to learn a little.

 

I need to check the front pulley but the rear was OD. Car made 19lbs with a 431, 270cc intake runner 72 cc combustion chamber at 9:1 It was spun hard. Meth was just to keep the IATs in check. It made 984 wheel. I'll check the front pulley when I go to the shop tomorrow. This setup was spun to 7300 rpm too. EDIT. Even with meth it went through the traps with 180+ degree IAT's.

 

HA! Spun hard is an understatement! I can see meth working better at 19psi than it would at 9psi. I saw little if any change in IAT's between meth and no meth. Find a way to introduce the meth downstream of the blower and you'd have something worthwhile on a mildly boosted TVS rig. That's essentially what E85 does and why it works so well on P/D blowers.

 

693 whp in dead of AZ summer with my setup.

https://www.corvetteforum.com/forums...p-no-meth.html