How best to increase cubic inches?

[Homie]

OK, after doing some looking around the forums, and with the help from several posters, I'm pretty sure I'm gonna go with a Gen III vert and mod the hell out of it.

Here is my question. I am eventually going to pull the engine and go all forged. While I have it out, and since I'm going to put all new internals in it, I want to maximize cubic inches.

I've been doing some reading, and it seems that stroking these V-10s is kind of iffy. But I saw several people mention sleeving them.

Can anyone fill me in on what are the practical ways to increase cubic inches? I want to maximize them in any practical way, but if it is going to cost a hell of alot more $$$ for just a few cubes it probably isn't worth it.

Thanks for any help!

 

[plumcrazy]

what are you final goals for HP ?

are you going to SC or TT ?

 

[Homie]

Plumcrazy, no hard-fast final goals. My thinking was to completely forge the engine and put on the best heads available (Strikers I believe they are from my reading on the forum). Then if I still feel I want more horsepower bolt on a supercharger (no TT--I really want tons of torque at low RPM rather than hight RPM horsepower, hense the desire to maximize cubic inches).

Thanks!

 

[plumcrazy]

strikers are pretty far from practical. talk to greg good about head work and he can help with the build too. 713-290-1103

you can get 600rwhp safely without strikers, more if you wanna bump up the CR. but then adding a SC later is going to be a problem. best thing to do is figure out your HP goals and build accordingly.

to me it sounds like you want a gen2 with a roe SC on it.

how much money are you planning on for this engine build ?

PS: stroking a v10 is fine. you'd be hard pressed to find any big HP vipers that re not stroked. if you are going to stay N/A, dont do it.
adding cubic inches isnt so important, its not a chevy 350

 

[Viper X]

Hmmm, not sure why you'd want to add cubic inches as you've got 505 already.....

That said, I did exactly what you are contemplating and went 530 ci big bore, wet liner, all forged, Stryker heads, solid lifter cam, headers / exhaust, etc. My engine was built by Exotic Engine.

I'm sure there are a few guys who can do a proper "stroker" engine, but I'd be really careful here as many of these have not been well sorted out in the past.

I went with the Paxton too with 12lbs of max boost. I've been pretty happy with the engine work, just not too happy with the tune until I had DC Performance tune the OE computer. I tried the Paxton "split second" timing puller, tried the AEM piggy back set up and let several guys try to tune it and it always had drive-ability issues that AEM could not figure out.

With the current conservative DC tune on 91 octane gas in the OE computer (Kalifornia), the car makes over 900 rwhp and over 850 rwtq. The torque curve is huge and the car (now properly tuned) starts and runs like OE as long as you keep the throttle far from the carpet and it passes the sniffer.

Anybody could drive it to the grocery store.

Now, when you spin it up a bit, like over 3000 rpm (6600 rpm rev limiter - a benefit of the big bore approach), the car is scary / crazy fast. It just keeps pulling. I've won a couple of 1/2 mile drag races with it and it would likely be competitive in the mile (especially if I added a bit of boost and race gas with more timing.)

Some other things to consider. As stated above, you must determine what your final goal is before you start as a FI engine needs low compression to live and make big power while a NA engine needs higher compression to make power. You must chose this before you begin your project.

Also, you will need to upgrade the clutch, trans and diff, 1/2 shafts and rear tires so keep this in mind or you will break things.

FYI, the new Nitto NT05R's work very well at the rear of the car on stock rims.

Good luck,

Dan

 

[Homie]

Thanks a ton guys.

As far as money to spend, I haven't really thought that through. I've got plenty of money to go all out, but I definately want to plan it out.

Viper X, I've always heard just what you are saying. If you want to totally maximize power to forced induction, you have to plan ahead of time and go low compression.

But what if I didn't want the gas milege trade offs with low compression? My thoughts are that I go with medium compression (maybe stock), but maximize cubes, heads, manifold, exhaust, etc., then if I'm still not happy bolt on a supercharger to still gain a good bit more. Yes, I'd be giving up some versus if I went low compression, etc., but I'd still have like 700 rwhp or something nutty, for SURE more than I could ever want.

That make any sense? In other words, can't you bolt a supercharger up to a stock gen 3 and get a pretty good boost? Seems you could do the same to a gen 3 that just has better breathing heads, exhaust, etc. and get a similar boost, but to an already higher HP engine.

Hope that made sense. Thanks again guys.

 

[plumcrazy]

nope, didnt make any sense

 

[Sneaky Pete]

Sounds ******** to me.

If you're going to build a Viper engine, decide on NA vs FI and build accordingly. Doing medium compression will lead to unimpressive results and poor satisfaction in the long run. If you're concerned with fuel economy, go buy a hybrid.

 

[1fast400]

Go to a tuner, pay them. They do this for a living, you don't. Don't blow your car up.

 

[Viper Specialty]

You absolutely need to figure out if you are going to be FI, or NA. There is a big difference in the way you will build the engine.

First of all, for NA, you can do wet sleeve big bores, strokers, major head work, etc. It is a very pricey approach, but very reliable in the long run when done correctly. Focus on a light and efficient rotating assembly, head and cam combination, and intake configuration. Oiling system and crank changes will be needed if you intend to rev higher.

For SC or TT, you should focus more on strength. Those extra cubes become irrellevent in comparison to the rigidity of the block and cylinder walls. Minimal overbores should be used, and dont bother stroking unless it is minimal and you need to clean the journals anyway. Due to the deck height of the Viper block, large strokes will result in either a short compression height on the piston, impacting ring land structure, dome thickness, etc- or your rods will be quite short, and your r/s ratio will be very poor. Overall, they dont lend themselves to long life, especially in FI cars. However, small bores and stroke changes like most tuners use are negligible, they are produced that way to account for wear of the incoming core engines. These are not the cases I am referring to. You should instead be focusing on a strong rotating assembly, stud kits, oiling, a nice set of heads [dont have to go crazy with FI heads unless you are looking for massive power where heads are going to become a restriction] drivetrain and safety changes.

You need to consider the power you will make, and the application of the car. If you are a track rat, and only want 600-700 horsepower, built NA all the way. If you want budget power, not for track use, slap on a Paxton SC onto a mildly modded engine. If you want BIG power, a fully built TT configuration is the way to go.

 

[1BADGTS]

Thanks a ton guys.

As far as money to spend, I haven't really thought that through. I've got plenty of money to go all out, but I definately want to plan it out.

Viper X, I've always heard just what you are saying. If you want to totally maximize power to forced induction, you have to plan ahead of time and go low compression.

But what if I didn't want the gas milege trade offs with low compression? My thoughts are that I go with medium compression (maybe stock), but maximize cubes, heads, manifold, exhaust, etc., then if I'm still not happy bolt on a supercharger to still gain a good bit more. Yes, I'd be giving up some versus if I went low compression, etc., but I'd still have like 700 rwhp or something nutty, for SURE more than I could ever want.

That make any sense? In other words, can't you bolt a supercharger up to a stock gen 3 and get a pretty good boost? Seems you could do the same to a gen 3 that just has better breathing heads, exhaust, etc. and get a similar boost, but to an already higher HP engine.

Hope that made sense. Thanks again guys.

The motor your talking about building- a worked stroker with a blower on it is probably in the 50 grand range (the crank ALONE is going to be close to 6k ) and you worried about gas mileage.

 

[Homie]

Haha, good point Thanks for all the replies guys.

Question: By going all-out blower mode, isn't not just gas milege affected--but also generally streetability?

Is it not the case that lowing compression ratio generally decreases low RPM (non-boosed) HP and general responsiveness?

I realize that dropping compression ratio a good bit is the only way to totally maximize boosted HP. But here is what I'm thinking.

Let's assume the Viper has 450rwhp stock.

Let's assume that bolting a Paxton on to that stock Viper adds 100rwhp.

I rebuild the motor, go all forged, ported or aftermarket heads, but keep it NA, and keep compression stock. Let's say that gets me to 550rwhp stock.

Now, 550rwhp will probably totally satisfy me. But let's say for some reason I want more. Can't I STILL bolt on a Paxton that then takes me from 550rwhp to (at least, improved heads would probably mean a bit more) 650rwhp, i.e., the same 100hp jump I would have got if I bolted the supercharger onto the stock motor?

So, if I was 95% sure that 550rwhp would satisfy my ultimate desires, and 99.99% sure that 650rwhp would, it seems to me that this is a very good option to consider, rather than dropping compression a good bit, losing some low end, in order to potentially go all out for 800+ rwhp when there is such a slim possibility I'll ever want it.

That make any sense? Is everything I said totally wrong?

Thanks for walking this through with me

 

[plumcrazy]

makes sense.

install a paxton on a stock motor car and you have 650rwp SAFELY. no driveability issue at all

build the motor at basically stock CR (somewhere around 9:1) and you would have about 550rwhp (talk cost later) no driveability issues at all

to most, thats enough power.

same engine with a base paxton will likely be 750rwhp with no driveability issues at all. at this point to go any further you will need a REAL fuel system. the base paxton kit fuel system is junk. a real fuel system to support this correctly will run you around $2000 ~, then you can easily get 800+rwhp and again zero driveability issues.

all the driveability issues are in the quality of the parts and most importantly the tune. find a trusted tuner from this site who is close to you and let him tune it corectly.

my car makes 800+, driven 12K miles on the current setup in al kinds of conditions and have had zero issues.

trusted tuners that can be found on this site that i would personally use are DLM (doug levin in south florida), underground racing (charlotte,nc), A.R.T (buda texas), DC performance (california), viper specialty (buffalo,ny)

 

[1BADGTS]

Haha, good point Thanks for all the replies guys.

Question: By going all-out blower mode, isn't not just gas milege affected--but also generally streetability?

Is it not the case that lowing compression ratio generally decreases low RPM (non-boosed) HP and general responsiveness?

I realize that dropping compression ratio a good bit is the only way to totally maximize boosted HP. But here is what I'm thinking.

Let's assume the Viper has 450rwhp stock.

Let's assume that bolting a Paxton on to that stock Viper adds 100rwhp.

I rebuild the motor, go all forged, ported or aftermarket heads, but keep it NA, and keep compression stock. Let's say that gets me to 550rwhp stock.

Now, 550rwhp will probably totally satisfy me. But let's say for some reason I want more. Can't I STILL bolt on a Paxton that then takes me from 550rwhp to (at least, improved heads would probably mean a bit more) 650rwhp, i.e., the same 100hp jump I would have got if I bolted the supercharger onto the stock motor?

So, if I was 95% sure that 550rwhp would satisfy my ultimate desires, and 99.99% sure that 650rwhp would, it seems to me that this is a very good option to consider, rather than dropping compression a good bit, losing some low end, in order to potentially go all out for 800+ rwhp when there is such a slim possibility I'll ever want it.

That make any sense? Is everything I said totally wrong?

Thanks for walking this through with me

Its just an insane amount of money to spend (which you will absolutely NEVER EVER get back on resale ).Your better off buying a Gen 4 adding bolts ons (600rw hp )that will have a full warranty with much beter resale.Remember even if you overbuild the blower motor issues can happen (fuel pump failure ,bad load of gas ect ) and your on your own without a warranty.Just because its the best forged parts ect should something happen to cause detonation your not covered .

 

[Homie]

Thanks guys.

Plum, I guess I didn't realize you could get 650rwhp with just a blower upgrade. Is that with exhaust and blower cam too, or a totally stock Gen3 with a Paxton?

If you can get 650rwhp so easy with just a blower it seems the logical thing to do is just bolt on the Paxton, and if 650rwhp ain't enough THEN spend the crazy money to forge the engine and otherwise go all out. I'm about 99.99% sure 650rwhp would do me good for life. I just want something fast as hell on the streets--I have no intention to track it or anything.

Thanks!

 

[Kai SRT10]

Just bolt on a Paxton. If you aren't going to track the car, a naturally aspirated build doesn't make sense. A naturally aspirated build will likely cost you 5 times as much per horsepower gained compared with a bolt-on Paxton kit.

 

[plumcrazy]

650+ safely on a stock motor if done by the trusted tuners here.

Where are you from ?

 

[Homie]

Houston. I suspect there is a very good tuner in Houston

 

[ViperGeorge]

My Gen 3 Paxton car just made 646 rwhp on a DynoJet. It made exactly 446 rwhp before the blower. Has forged internals, but stock compression ratio. Has Diamond Pistons with lower ring lands to protect the rings from heat. Motor was built by Arrow Racing. DC Performance flashed the stock PCM. When I get a chance I want to get a great tuner to tweak it some. Its plenty safe right now with A/F about 11.3-11.5 under boost.

 

[plumcrazy]

gbatejan. Frank smith is coming to CT very soon. Let him tune it. Not too many guys cqn tune as well as him.

 

[Green Viper]

At last year's Washington dyno day there was a Copperhead Gen 3 Viper with a Paxton supercharger, headers, throttle body and exhaust that pulled 706 at the rear wheels, he has the shirt and pictures to prove it. The pictures are in the Washington region section under dyno as an ad for the event in two weeks. There is also a video of the dyno pull on the Washington region web page.

While I went naturally aspirated, its hard to argue with a performance like that...

 

[Twister]

Thats what I was gonna say...No one has EVER dynoed 550 rwhp on a properly running gen3 with a paxton...Lowest Ive ever heard of was 605 rwhp..

615-655 seems to be the norm on stock engines with a paxton added..

i have to disagree with Plum crazy just a lil as their have been plenty of guys dyno in the 500-530 rwhp range on their gen3's with just bolt ons all the bolt ons and heads are gonna get you more than 550 rwhp

Do all the bolt ons..

kn air intake...headers...no cats...throttle body...exhaust...under drive pulley...arrow rockers...sct tune or vec3 tune ( I belieave their is one for sale in the classifieds)

and hit 500-530 rwhp SAE..


Honestly your car is probally only 440 rwhp stock...throw another 75 rwhp on her from these bolt ons and then see how you feel with 515 rwhp...The best part is your still just playing with your stock engine and dont have much to worry about...

If the 515 rwhp dosent satisfy you THEN think about FI heads or NA heads...cam ect...

These cars just arent like the others you may have played with..I added qround 100 rwhp to my 2004 vette with Heads and cam..Total cost was only around 5K includeing install...

Thought I could easily do the same with my viper till all these guys told me it would cost 15K

 

[dipapa]

keep the viper stock and go built a turbo 4 ****** and then you will have 2 cars for the same price of 1 built force induction viper.

OR

take stock viper, slap on a paxton, tune it conservatively and be done


If you ask for too much thats what you will end up paying!!!

Trust me, many of us that been through/going through that/this know that already.

 

[RTTTTed]

I have 2 supercharged Gen 2 Vipers

2000 ACR 600rwhp with Paxton and 802rwhp with the Nitrous turned on. Runs exactly the same as stock under 3,000rpm. Unitrax halfshafts.

2001 GTS with freshened engine and Ross 9-1 pistons, rockers, pushrods, Fidenza flywheel, mildly ported heads and backcut valves, Titanium rear axles, wires, 708 cam, Roe TBs, CAI, 14" lightweight brakes, etc. about 790rwtq/750rwhp. This car has a 100hp Nitrous system 80% installed that would add anther 150rwhp and more torque - if I need/want it (maybe this year?).

I think it's a mistake to concentrate on just engine, the brakes are extremely important as well. More hp means more breakage unless you buy stronger parts, fuel system, etc. I love my Roe sc. The Paxton is much easier to drive since it has traction.

Gen 3 vert means that you don't want to go to a racetrack? Road course and dragstrip don't allow fast (slower than 13sec ET at drag strip) convertibles. Roll cages are required to go as fast as a GTS or coupe. GTS and coupe are "considered safe" until 11.5 ET and can be run in higher classes for road racing and road rallies than open cockpit cars. On the road the safety issue is up to you. Only Gen 3 coupe was built in 2006.

Mileage FYI;
my 2000 Paxton 9.5-1 GTS ACR got 18.5 to 19.5 average over thousands of miles.

my 2001 Roe supercharged GTS with 9-1 compression got 19.8mpg across the continent.

other 4 Gen2s naturally aspirated usually got .2mph better mileage than my Roe car. 2008 SRT10 stock got 22mpg cross country.

Both cars are 9 second cars (Paxton on Nitrous). Paxton car for sale.

Ted