viperrt96
Enthusiast
Hello fellow GenI owners
I’m offering a mod I did to my virtually stock (engine) Viper some time ago that netted me good results. I have since then modded my engine even further and of course tried different products. So I have some experience here. I sold that set to another owner that has gained him some good results and I’ve been encouraged to offer it for all GenI owners so here it is. I can not provide you with any dyno results nor will I make any promises.
Why? Because this is common sense.
Please read why?
I know what made a difference in my car and what didn’t. The ¼ mile is where I tested it. This mod could be disputed the same as saying that adding just smooth tubes (K&N filters also) will get you 10hp. I’m not here to dispute that but it never dropped anything from my ET. I know. That was the first mod I ever did to my car because it was the cheapest. It makes sense after you look and study the stock air tubes but the tubes alone who knows. If anything it takes a combination of things and this is just one of them. Here are the facts and the combination that took a ½ second off of my ¼ mile ET and added almost 10mph. My totally stock 96 RT10 with me driving it would run high 12.9’s (best) to a 13 flat and around 106-8mph (w/2.0 60ft-stock pilots). Please do not post what it should have run. The facts were the facts for me. No matter how aggressive I drove it or launched it, that’s what it would run consistently and please understand tracks do differ. I ran it at only one track. Smooth tubes added – no improvement or difference in my ET that I could tell (trap, 60ft or?). Next for me was the cats (exhaust). Two reasons: One was the ridiculous heat that was discoloring my (White) side sills, and the other was it just made sense. The 96RT10 shares the same rear exhaust set-up as the GTS but they didn’t come with the side resonators. Heck why spend $1200 for a cat-back when those stock Cats are so restrictive. So I bought a set from Sean Roe and my car ran Consistent 12.8’s and would dip in the 12.7’s and I did see a 12.69 once (trap speed was consistently over 110). Now the throttle bodies. I studied these thoroughly and noticed the following.
Facts:
Smooth tubes (2.5”) = 63.5mm (that’s what’s available)
GenI TB’s= opening is 58mm but chokes down to 56 mm WTH?
That’s a big difference between 63.5 and 56mm.
The following Mod is what I did and I have illustrated it for you.
Here is a GenI stock (56mm) throttle body compared to my 62mm
View from the rear.
When making these it was critical to make the new throttle plates the same angle as stock so the TPS sensor angle would remain the same so idle and the throttle up range would not be compromised.
Made a fixture so we could hold these and position them to their own centerline (these are cast and then machined) so we could follow the factory bore rather than make our own. You do not want binding of any kind.
Making the throttle plates. Not what people think? These were first cut out of aluminum that was the exact thickness as stock. They were then angle mill cut to size. Throttle plates are not perfectly round. You want them to seat the same as the factory ones so they don’t bind up and seal good.
Here we ran into another obstacle. The stock opening on the TPS rod that holds the Plates is only 59mm wide. We had to lengthen those as well so the 62mm would fit.
Here is the finished product. These look stock!
My final results after adding these.
I ran consistent 12.6’s and would dip into the 12.5’s
To summarize:
Smooth Tubes (K&N Filter)
Sean Roe high flo cats only (otherwise stock exhaust)
62mm throttle bodies
Made my car a ½ second faster in the ¼ and it added almost 10mph (avg) to my ET. That’s about 6 car lengths in just the quarter.
I’ve got one bit of news to share also while I’m at it. Your Stock Intake manifold opening is only 59mm. What does that mean? Buying 62mm Throttle bodies will do you no good unless you modify the intake too. Keep in mind if the opening from the manifold is only 59mm and the TB’s are 62mm. You’re only getting 59mm. I know I had to take mine off twice to do so. First was for the 62mm TB’s and then again for my Accufab 65mm’s. That’s what I’m currently running on my car now. I will tell you this. I added the 65mm with my stock set-up and it actually hurt my ET. The car never saw a 12.6 again with the Accufabs on it. I was doing a cam and head work anyway so I didn’t worry about it. I’m now pushing near 500hp (rwhp) and my car has ran a best of 11.67 (1.91 60’ w/Kumhos) @ 122mph. It’s all naturally aspirated with no power adders. Not bad for an old GenI.
Here is what I’m offering
I will only modify your throttle bodies. I will return only your throttle bodies. It will include: Refurbishing and replacement of the bearings (if necessary), all cleaning, match machining and assembly.
Throttle bodies only
59mm $250 – (TB's only)includes gaskets and Shipping
Note: I’m offering the 59mm in case you feel uneasy about removing your intake manifold for modifying. This is the most you can get from the stock opening of your intake manifold.
62mm $300 – (TB's only)includes gaskets and Shipping
Note: I’m also offering any size you want up to 62mm. If you want 60mm, 61mm. We can do it. The price difference is the modifying of the Rod to accept 60-62mm plates
Match machine both Intake and Throttle bodies to your specified size
62mm $650 – (Intake and TB's)includes all gaskets and shipping
I will machine both intake and throttle bodies to the size specified and assemble. It will include all gaskets (Intake,TB’s, and IAC) and shipping. When sending me your Intake and TB’s only remove the Idle Air control valve (passenger side-behind just below TB), the TPS sensor and all throttle cable hardware. It will not be necessary to remove the injectors. I would prefer you not remove them.
Wondering how much it cost to convert your car to Accufab 65mm TB’s?
Accufab 65mm = $550
New 3” hoses = $80
Modified Air box = $150
Local mach shop
To open Intake ? = ? ($200-$300)
Fact is if you haven’t modified your engine internally (cam or headwork) 65mm is overkill and will gain you nothing. Most tuners will agree and in fact it will hurt the performance. I know it did mine.
This Mod worked for me. Along with the cats and smooth tubes it made my car perform. No doubt your throttle response will be quicker. No Idle hang or surging. These perform better than stock. If interested you can PM me and I will reply to all.
Thanks
I’m offering a mod I did to my virtually stock (engine) Viper some time ago that netted me good results. I have since then modded my engine even further and of course tried different products. So I have some experience here. I sold that set to another owner that has gained him some good results and I’ve been encouraged to offer it for all GenI owners so here it is. I can not provide you with any dyno results nor will I make any promises.
Why? Because this is common sense.
Please read why?
I know what made a difference in my car and what didn’t. The ¼ mile is where I tested it. This mod could be disputed the same as saying that adding just smooth tubes (K&N filters also) will get you 10hp. I’m not here to dispute that but it never dropped anything from my ET. I know. That was the first mod I ever did to my car because it was the cheapest. It makes sense after you look and study the stock air tubes but the tubes alone who knows. If anything it takes a combination of things and this is just one of them. Here are the facts and the combination that took a ½ second off of my ¼ mile ET and added almost 10mph. My totally stock 96 RT10 with me driving it would run high 12.9’s (best) to a 13 flat and around 106-8mph (w/2.0 60ft-stock pilots). Please do not post what it should have run. The facts were the facts for me. No matter how aggressive I drove it or launched it, that’s what it would run consistently and please understand tracks do differ. I ran it at only one track. Smooth tubes added – no improvement or difference in my ET that I could tell (trap, 60ft or?). Next for me was the cats (exhaust). Two reasons: One was the ridiculous heat that was discoloring my (White) side sills, and the other was it just made sense. The 96RT10 shares the same rear exhaust set-up as the GTS but they didn’t come with the side resonators. Heck why spend $1200 for a cat-back when those stock Cats are so restrictive. So I bought a set from Sean Roe and my car ran Consistent 12.8’s and would dip in the 12.7’s and I did see a 12.69 once (trap speed was consistently over 110). Now the throttle bodies. I studied these thoroughly and noticed the following.
Facts:
Smooth tubes (2.5”) = 63.5mm (that’s what’s available)
GenI TB’s= opening is 58mm but chokes down to 56 mm WTH?
That’s a big difference between 63.5 and 56mm.
The following Mod is what I did and I have illustrated it for you.
Here is a GenI stock (56mm) throttle body compared to my 62mm
View from the rear.
When making these it was critical to make the new throttle plates the same angle as stock so the TPS sensor angle would remain the same so idle and the throttle up range would not be compromised.
Made a fixture so we could hold these and position them to their own centerline (these are cast and then machined) so we could follow the factory bore rather than make our own. You do not want binding of any kind.
Making the throttle plates. Not what people think? These were first cut out of aluminum that was the exact thickness as stock. They were then angle mill cut to size. Throttle plates are not perfectly round. You want them to seat the same as the factory ones so they don’t bind up and seal good.
Here we ran into another obstacle. The stock opening on the TPS rod that holds the Plates is only 59mm wide. We had to lengthen those as well so the 62mm would fit.
Here is the finished product. These look stock!
My final results after adding these.
I ran consistent 12.6’s and would dip into the 12.5’s
To summarize:
Smooth Tubes (K&N Filter)
Sean Roe high flo cats only (otherwise stock exhaust)
62mm throttle bodies
Made my car a ½ second faster in the ¼ and it added almost 10mph (avg) to my ET. That’s about 6 car lengths in just the quarter.
I’ve got one bit of news to share also while I’m at it. Your Stock Intake manifold opening is only 59mm. What does that mean? Buying 62mm Throttle bodies will do you no good unless you modify the intake too. Keep in mind if the opening from the manifold is only 59mm and the TB’s are 62mm. You’re only getting 59mm. I know I had to take mine off twice to do so. First was for the 62mm TB’s and then again for my Accufab 65mm’s. That’s what I’m currently running on my car now. I will tell you this. I added the 65mm with my stock set-up and it actually hurt my ET. The car never saw a 12.6 again with the Accufabs on it. I was doing a cam and head work anyway so I didn’t worry about it. I’m now pushing near 500hp (rwhp) and my car has ran a best of 11.67 (1.91 60’ w/Kumhos) @ 122mph. It’s all naturally aspirated with no power adders. Not bad for an old GenI.
Here is what I’m offering
I will only modify your throttle bodies. I will return only your throttle bodies. It will include: Refurbishing and replacement of the bearings (if necessary), all cleaning, match machining and assembly.
Throttle bodies only
59mm $250 – (TB's only)includes gaskets and Shipping
Note: I’m offering the 59mm in case you feel uneasy about removing your intake manifold for modifying. This is the most you can get from the stock opening of your intake manifold.
62mm $300 – (TB's only)includes gaskets and Shipping
Note: I’m also offering any size you want up to 62mm. If you want 60mm, 61mm. We can do it. The price difference is the modifying of the Rod to accept 60-62mm plates
Match machine both Intake and Throttle bodies to your specified size
62mm $650 – (Intake and TB's)includes all gaskets and shipping
I will machine both intake and throttle bodies to the size specified and assemble. It will include all gaskets (Intake,TB’s, and IAC) and shipping. When sending me your Intake and TB’s only remove the Idle Air control valve (passenger side-behind just below TB), the TPS sensor and all throttle cable hardware. It will not be necessary to remove the injectors. I would prefer you not remove them.
Wondering how much it cost to convert your car to Accufab 65mm TB’s?
Accufab 65mm = $550
New 3” hoses = $80
Modified Air box = $150
Local mach shop
To open Intake ? = ? ($200-$300)
Fact is if you haven’t modified your engine internally (cam or headwork) 65mm is overkill and will gain you nothing. Most tuners will agree and in fact it will hurt the performance. I know it did mine.
This Mod worked for me. Along with the cats and smooth tubes it made my car perform. No doubt your throttle response will be quicker. No Idle hang or surging. These perform better than stock. If interested you can PM me and I will reply to all.
Thanks
