Engine buildup - advice req'd

[GTSjbud]

I need members to advice me on how to build/modify my current Gen. II Venom 550 engine to make 700 HP/TQ (or higher) at the real wheels. I am a Viper newbie and want to make an education decision before I modify the engine...hence the reason for this thread. For your info, I have been speaking with Joe Donovan and Greg Good about the build. I appreciate their knowledge and want to hear other Viper members ideas.

I want to keep the engine Normally Aspirated running on pump gas (no race gas). I want to have the ability to kick but in street racing. I have chosen to stick with a NA car instead of going with a SC or TT car for around town driveability. I also want an engine that will have longevity and won't grenade on me.

I have listed the engine areas below. I have noted the existing data and then asked questions for members to comment on.

Block
Gen. II stock (has not been bored)

1. What is the maximum size a Gen. II engine can be bored? Is it the sleeves themselves that get bored or is it the block? If it is the block that gets bored then I assume that oversized sleeves are installed. Is this correct?

2. I've heard of Darton sleeves...are they recommended?

3. What is the largest cubic inch displacement attainable with a bored block?

4. If I was to stroke the engine what would be the recommended connecting rod ratio so that the engine will last and not grenade?

Heads
Gen. II ported by Hennessey (flow unknown)
Valve size unknown
10:1 compression

1. Should I have my existing heads sent out for porting and polishing?

2. Can Gen. III heads be installed on a Gen. II engine? I have heard that Gen. III heads are designed/engineeried a little better than Gen. II heads. Is this correct?

3. If Gen. III heads are recommended for installation, should they be ported and polished for higher flow? What is the max flow numbers for a Gen. III head?

4. If Gen. III heads are recommended, does anyone have a set to sell? Or does anyone have a set of Stryker heads (or other) to sell?

5. What valve size is recommended?

6. What compression ratio is recommended?

Cam
Hennessey cam

1. What is recommend for a cam?

2. Aftermarket recommendations?



Pistons
stock

1. Aftermarket recommendations?

2. Should the top of the pistons be coated?

3. Should the piston skirts be coated?

Rods
stock

1. Aftermarket recommendations?

Crank
stock

1. Aftermarket recommendations?

Lifters
Comp Cam roller

1. Aftermarket recommendations?

Rocker Arms
T&D 7:1

1. Aftermarket recommendations?

Intake Manifold
Extrude Honed by Hennessey

1. Should I use my Gen. II intake that is extrude honed?

2. Is a Gen. II intake recommended for better flow over my extrude honed Gen. II manifold?

3. Will a Gen. III intake mount up to Gen. II heads (only if I decided to stick with Gen. II heads)?

4. If a Gen. III intake is recommended, does anyone have one to sell?

Throttle Bodies
65mm Accufab

1. What size of throttle body is recommended?

2. Aftermarket recommendations?

Fuel Injectors
stock

1. What size is recommended?

2. Aftermarket recommendations?

Engine Controller
stock - modified by Hennessey ...I think?

1. I honestly don't understand the difference between VEC 2/3 etc. I'm all ears for educating. I want to use a controller that is easy for someone like myself to use as I am located in Canada and not convieniently located to tuners in the US. I'm therefore on my own.

2. Does Mopar make a controller that is sufficient for my application?



I am also open to any other info that you might think is pertinent to this build. So have at er! In addition, if anyone has aftermarket parts to sell for the build, just let me know.

Thanks in advance for all your comments and recommendations!!

Here is a link to my Viper build if you are interested in looking at my engine (before modifications) http://forums.viperclub.org/showthread.php?t=605759
Cheers
Jason

 

[Camfab]

Stryker Heads
Big Cubic Inches
Huge Cam
Increased Compression
Coated Pistons
Better Rods
Fuel System upgrade and I really don't see it being more reliable and streetable than a mild blown set up. I went N/A as well, but it costs way more money than a blown motor and your expectations are potentially unreasonable. A 700 rear wheel HP car is not going to have around the town drivabillity! Your talking about 800+ crank shaft HP. You might as well go Twin Turbo, because by the time your done you'll have 25 grand in the motor build. By the way, your a man cut from the same stone as I am, nice work on your build up!

 

[plumcrazy]

talk to KAI on the gen3 board about it

 

[treesnake]

Ask Joe about the engine we are building for my car. It is going to replace the cast piston engine currently in my 01 GTS. It is being built at Arrow. Balance, blueprint, Oliver rods, JE coated pistons with lowered ring land to take s/c boost (they will be good for TT next) All per Joe Donovan. Billett mains, heads etc. Set of Stryker heads w/ jesel rockers. PBJ "custom grind " Comp. cam. Roe S/C with Vec 2 (maybe AEM) Joe completely rebuilt my fuel system last year to feed the animal. Not sure what pulley yet but I will easily be at 700-800 with little or no "drivability issues due to Joe's tuning. And for when I go to the track, I will pop my Nos card in the Vec for an extra 100 h.p. Ask joe about the engine he is building for Mike with the sapphire GTS.

Is your car still there? I am going to see Joe today to order some more parts. I can take some photos of your car at the shop if your interested.

 

[Disturbed]

700rwhp N/A is going to be tough. 600-650rwhp is possible.

My car has Greg Good heads, 11.6:1 cr, 510cid, bellinger headers, HF cats, T&D RR and a cam that is too small (much like your stock cam) and a tune. I make a wimpy 555rwhp 610rwtq. I still have a stock fuel system, TB and intake system.

I would get a custom intake mani. The stock intake mani's are not too great. The runners are too long and the plenum is too short.

PM and I will tell you more. I've goto run to work now.

 

[EllowViper]

This may or may not apply to your questions at this early stage, but a build such as you are contemplating requires a holistic approach. I stumbled on the article when researching some tuning questions I had with my ROE system, so the article gets into some unrelated stuff, but its a great discussion when considering trade offs regarding Compresison Ratios, tuning, fuel requirements, etc. (especially pages 4-6 when considering your pistion and chamber designs and assumptions about compresison ratios). I'm going to post the link over on the tuning section, but at least give it a quick read and you can ask your builder about some of the issues presented. Have fun with the buld!!
http://www.streetrodstuff.com/Articles/Engine/Detonation/index.php

 

[Knight Viper]

GTSjbud, I wanted to so the same thing as you this time last year and after many hours of research and phone calls I came to the decision that a NA build on this motor would be a expensive , difficult and frustrating adventure. For a good NA a build you’re asking all the right question for what you need to make power but just simple things like the lack of cam bearing really keeps our motors from living in the high RPM range where a good NA motor should. I did a Roe blower and other mods with Joe a PBJ (AWSOEME gentleman and tuner) and will be pulling the motor this year for heads, cam and forged pistons to be able to run more boost. If I could start all over I would just go twin turbo and be done and I think you will save money and be much happier in the long run. You can have just about anything you want with a good TT build; Power levels you wont reach with a NA build and daily drivability like or better than stock. My .02 KV

 

[klamathpro]

Engine buildup is bad. Change your oil immediately!

 

[GTSjbud]

Stryker Heads
Big Cubic Inches
Huge Cam
Increased Compression
Coated Pistons
Better Rods
Fuel System upgrade and I really don't see it being more reliable and streetable than a mild blown set up. I went N/A as well, but it costs way more money than a blown motor and your expectations are potentially unreasonable. A 700 rear wheel HP car is not going to have around the town drivabillity! Your talking about 800+ crank shaft HP. You might as well go Twin Turbo, because by the time your done you'll have 25 grand in the motor build. By the way, your a man cut from the same stone as I am, nice work on your build up!

Hey Camfab, I appreciate the info and happy to hear that we are cut from the same stone! Keep watchin the build to see what I change and modify.

Cheers
Jason

 

[GTSjbud]

Ask Joe about the engine we are building for my car. It is going to replace the cast piston engine currently in my 01 GTS. It is being built at Arrow. Balance, blueprint, Oliver rods, JE coated pistons with lowered ring land to take s/c boost (they will be good for TT next) All per Joe Donovan. Billett mains, heads etc. Set of Stryker heads w/ jesel rockers. PBJ "custom grind " Comp. cam. Roe S/C with Vec 2 (maybe AEM) Joe completely rebuilt my fuel system last year to feed the animal. Not sure what pulley yet but I will easily be at 700-800 with little or no "drivability issues due to Joe's tuning. And for when I go to the track, I will pop my Nos card in the Vec for an extra 100 h.p. Ask joe about the engine he is building for Mike with the sapphire GTS.

Is your car still there? I am going to see Joe today to order some more parts. I can take some photos of your car at the shop if your interested.

Hello Treesnake, thanks for the info. I will discuss more with Joe.

Oh, my car is with me in Canada...I am tweaking from afar.

Cheers
Jason

 

[GTSjbud]

talk to KAI on the gen3 board about it

I have just sent KAI a PM and asked him to respond to this thread.

 

[GTSjbud]

Hey Knight Viper & EllowViper...I will definitely read the engine build article that you linked and consider your advice given. I'll keep you posted as to what I learn.

Cheers
Jason

 

[Kai SRT10]

You can do it, but it will be expensive. Be prepared to spend 3 or 4 times as much for a naturally aspirated 700rwhp car than you would for a supercharged car making the same power. The reason for this is that you are going to have to replace/modify just about every piece of the engine with state of the art aftermarket parts.

I would highly recommend you call and talk to Kevin Singleton at Exotic Engine Development. He has built GTS engines making more than 700rwph and has a very good handle on what is needed. I believe that for naturally aspirated builds, there is no one with more experience and success than Kevin.

Here is his web site

http://www.exoticengine.net/


Besides Kevin, Hennessey has made some crazy n/a cars. A look at the published specs on his 800R will give you a clue to how he does it.

Basically, he bores and strokes the hell out of the engine (585 cubic inches), and combines the big cubes with good heads, high compression, and a good tune.

http://www.hennesseyperformance.com...t=wDmfkJHE&DoThis=Dodge+Viper&ActionReq=Where

Between increasing bore and stroke, you will get more power from stroking the engine, but there are some trade offs. As you know, if you go too far, you will alter the rod angle enough that you begin to add wear on your pistons/rings. I don't know what the limit is on rod ratio and angles. I stayed with the stock stroke on mine because I wanted to maximize durability and wasn't too concerned about squeezing all the available horsepower out of the engine.

Some things to consider:

You might want to build a high rpm engine. There are limits to what you can do here, but the Stryker castings will give you a leg up because they provide for greater valve train stability if you go down that path. You may have to get a custom crankshaft too, so you can play with bearing sizes and the rod/crankshaft interface. The crankshaft alone will cost about $5000 and take about 6 months to make. The good news is that it will weigh 30+ pounds less than your stock crank (that's rotating mass), which is good for both performance and durability. A custom crankshaft will also improve oiling. Again, Kevin has built some crazy high-revving engines. You should talk to him about this option.

A dry sump will probably net you about 40+ hp, and will contribute to the overall durability of your car. Certainly, if you are trying to squeeze out every last pony, it would be a good idea. With a Gen II car, you can get proven dry sump systems that allow you to keep your air conditioning (which you can't with a Gen III.)

Since you asked, Darton sleeves are highly recommended. They are strong, and the wet sleeve design provides some extra cooling. They require the use of Evans coolant, which is also a good change, as your car will run cooler. If you are going to significantly bore your engine, you will almost certainly need to get high performance sleeves of some sort. Nikasil sleeves might be another option, but to be honest, I don't know that much about them in Viper applications.

As for heads, the Strykers are the best you can buy, but they are very expensive. They provide better flow, more uniform combusion (allows for higher compression ratios) and they have larger water jackets so they run cooler. As noted above, they will also provide greater valve train stability if you decide you need to increase your redline. The only disadvantage of the Strykers is their cost. There are Strykers available for Gen II cars as well as Gen III.

I don't know anything about cams, except that the crazier you get with top end power, the more the car will buck and complain at idle and low speeds.

Coatings are good. Yes, get everything coated: Pistons, and ESPECIALLY bearings. Coatings are also (relatively) cheap.

As for rod and piston choices, you can't really go wrong with the top of the line components from the highly respected manufacturers (Oliver, Crower, Manley, JM, etc.) Just remember that most of these companies sell components of various levels of quality. It's more important to get the top shelf components than it is to stick to any particular brand. If you decide to go the high rpm route, then you should seriously consider titanium rods. If you are not going to build a high rpm car, then billet steel is a better (more durable) choice.

I'm currently running stock lifters. This is because I could not find a strong consensus on a really good aftermarket lifter that provided better performance.

I chose Jesel rockers over T&D, but that was not based on anything other than hearsay and the preferences of a couple of builders I talked to.

I am running stock throttle bodies. I don't know if you will need something better.

You will want bigger injectors. I am running 42# injectors in my car and they are not close to being maxed out, so you won't need to go crazy with 90# injectors.

You don't need a VEC2/3. Use the new SCT box to tune the stock ECU.

You are getting to the point where you will probably need upgrades to your fuel pump etc.

Billet main caps will be important.

If you want to run pump gas, I would shoot for compression ratio between 10.5 and 11. Any higher, and you are going to have issues.

 

[plumcrazy]

and greg good said there's more HP in those stryker heads as well if ya need it.

i KNEW Kai knew a lot about this stuff...damn Kai, thats a lot of info...

 

[Disturbed]

If you want to run pump gas, I would shoot for compression ratio between 10.5 and 11. Any higher, and you are going to have issues.

Not too sure about that one. I run 11.6:1 and it works fine on 93 pump gas.

 

[GTSjbud]

Keep the awesome info coming!

Can Gen. III heads and intake be installed on a Gen. II engine? Is there any advantage to doing this?

Cheers
Jason

 

[Disturbed]

PM Sent...hope it helps

 

[kwkshift]

Disturbed has an engine similar to mine. I think mine may have a larger cam, due to similar torque, but more hp. My car makes 600/ 615 at the wheels on 91 octane. I'm going to go to DC Performance and get a custom tune because I know there is a bit more power and driveability left in my combo.

Mine is a 510, with 11.7:1 compression, ported heads, T&D rockers, 70mm tb's, headers, etc.

I think to get to the 700 rwhp mark on pump gas, you would need about 540", some Stryker heads, similar compression to our motors, maybe some more rpm, (I only rev mine to 6000 rpm because power starts falling off at around 5700). That should get you in the ballpark. If not, then you may have to add something like a dry sump oiling system.

I will tell you, though, driving around in a nasty NA car is fun! The power is instantaneous. Just snap your fingers and WHAM! the car is changing lanes. It's a blast!

 

[Disturbed]

kwkshift,


Our motors are very close. I still run the stock Intake mani, TB and airfilters (ACR came with K&N's). I feel my cam is too small for this setup, it's about the same as a 708. I made a mistake and was too conservitive. I should have used a much larger cam. But I wanted a 100% street N/A street car to put 50kmi on. So I gave up some power...what a waste...shame on me.

GTSjBud,

If I was going to build again, I wouldn't go N/A. These cars just make WAY too much power with a set of TT.

But if I was going to go N/A again, I would use a GENIII motor as a base. Offset grind cank will get you 522cid. Also the GENIII heads flow better. I would get a custom intake mani...all viper intake mani's ****. Don't forget the lightweight internals, billet main caps, dry sump and coat EVERYTHING.

 

[Martin D]

Solid cam - .758 lift. Heads that flow 330 - 700 at the Wheels FTW!!!

 

[hemibeep]

A few short notes I learned.
1. the crank does have a little flex, still a good piece. had it balanced.
2. went with ross pistons, factory pistons are about 60 grams heavier, and have offset pins to lessen piston "slap", I had the pistons made with no pin offset.
3. I have heard that there may be an AMC cam bearing that will fit, as factory cam just rides in the block.
4. I would try to use crank for displacement, not bore. I had to resleeve a cylinder with a new sleeve and the heat went up slightly, would not want to do this for all 10 holes.
5. cylinder heads can make a large difference, just a light port job and intake port matching picked up 50hp on a stock "everything" else motor for me