Is a tune a requirement going to H.S. 1.7 RR's on a 2001 GTS? ---

[alwayscode390]

I was throwing around the idea of installing some Harland Sharp 1.7 roller rockers on my 2001 GTS.

I did some searching but not many people mentioned re-tuning their cars after an install.

Is it necessary to get a re-tune, or just a suggestion ... or not even worth the time?

I know on the gen 2 you are only going from 1.6 to 1.7 , so its not as big of an increase vs the Gen 1 with the 1.5 ratio.

Thanks ---

 

[Allan]

It seems that any mechanical modification that will affect volumetric efficiency would require a change in fuel mapping. -yes, tune would be suggested. .....otherwise, why even bother with the rocker arm change.

 

[Jack B]

Gen II's respond very nicely to 1.7 rockers. For information sake, the stock rockers are stamped junk.

 

[KNG SNKE]

Short answer no a retune is not "required".
To make the most out of your rockers yes a tune would be beneficial.

 

[Allan]

Short answer no a retune is not "required".
To make the most out of your rockers yes a tune would be beneficial.

I agree, just like installing a free flowing exhaust system. You don't have to anything but bolt it on, but to take full advantage of the mod..................

 

[Jeebs]

What kind of HP numbers can one see after putting 1.7's on. With or with out tune?

 

[alwayscode390]

I think people were posting 15 rwhp increases , but the engine feels like it can rev up quicker from less friction

I like that it will make your cam sound larger too from the increased lift ---

 

[evomind]

I think people were posting 15 rwhp increases , but the engine feels like it can rev up quicker from less friction

I like that it will make your cam sound larger too from the increased lift ---

Sounds like a lot of time, money, and effort for 15hp.

 

[Jack B]

Sounds like a lot of time, money, and effort for 15hp.

It is a simple upgrade and 15 hp is not the whole story, the effective power (under the torque curve) is much better. Peak hp numbers do not tell the whole story. If most people knew what the stock rockers looked like they would change them simply for the fact of removing the junk oem hardware.

 

[alwayscode390]

Seems like most mods are expensive and a hassle ... like $2000+ headers for 35 hp .

Its up to you if its worth it or not ---

 

[uvbnbit]

I think with my 1.7 HS's and B&B's, catless, I got 40-45 rwhp gain (pre-Roe). 15 here, 15 there, it adds up
I don't think it increases cam lift, just .1 duration. (aren't stockers 1.6?) I may be wrong though(first time ). Like mentioned previously, smoother/less stress on valve train.

 

[alwayscode390]

Who is recommended if I want to purchase a SCT tuner with a preloaded tune for this mod?

I decided to go for it and just purchased the stuff lastnight.

I have heard Roe, A&C, DC Performance ... but I didnt hear if anyone thought one was better than the other.

Thanks ---

 

[KNG SNKE]

Stock are 1.6 yes.

40-45rwhp pre roe seems a bit high but you had the old manifolds right?

On a 2001 you won't gain that much, our manifolds are much better oem so upgrading them from stock is not a huge increase. With a blower 20-40whp achievable but for a stock car less than 20. But on a positive note it definitely gives the exhaust a lumpier sound and a little more depth to it.

 

[uvbnbit]

Stock are 1.6 yes.

40-45rwhp pre roe seems a bit high but you had the old manifolds right?

That was combined 1.7's and B&B headers, 3" exhaust, no cats total. 25ish+15ish= 40ish

 

[KNG SNKE]

Different year car

 

[evomind]

That was combined 1.7's and B&B headers, 3" exhaust, no cats total. 25ish+15ish= 40ish

Thats like ricer horsepower math.
lol, jk

 

[1.8t]

It is a simple upgrade and 15 hp is not the whole story, the effective power (under the torque curve) is much better. Peak hp numbers do not tell the whole story. If most people knew what the stock rockers looked like they would change them simply for the fact of removing the junk oem hardware.

You ever seen GM rockers?? The ones in the Viper are battleships compared to the flimsy LSX rockers.

 

[99 R/T 10]

I don't think it increases cam lift, just .1 duration.

It will add lift to the cam profile. Takes the lift from .542 to a .575. Not an enormous jump but makes the 708 lumpier.................

 

[uvbnbit]

It will add lift to the cam profile. Takes the lift from .542 to a .575. Not an enormous jump but makes the 708 lumpier.................

did not know that. thank you for clarifying.

 

[alwayscode390]

It will add lift to the cam profile. Takes the lift from .542 to a .575. Not an enormous jump but makes the 708 lumpier.................

What does it take the "creampuff" cam lift to? ---

 

[99 R/T 10]

What does it take the "creampuff" cam lift to? ---

The lift on the "creampuff" cam is hte same as the 708 "Lumpy" cam. it is the difference in the overlap that makes the older cars lope they way thry do. Click on the link below, scroll down to the bottom of the page to see the cam specs:

http://www.theviperregistry.com/specifications.php

 

[alwayscode390]

Thanks for that link ... surprisingly there isnt much difference in the cams, wow.

I decided to go for it today and installed them with a friend.

All I can say is SMOOOOOOOOOTH ... waiting for my SCT so I can get my mail order ROE tune , hopefully tomorrow.

So far I am pretty happy about it ---

 

[dascorcha21]

Glad you like it man... i have I've packs on my back right now lol

now somebody needs to just buy my exhaust!

 

[alwayscode390]

I took a nap and barely could get out of bed to stand up LOL ... these cars are LOW, and not having a fender to put your weight on takes a toll HAHAH.

Good work bro ---

 

[ACPERFORMANCE]

We have done many 2001 setups exactly like yours. Their is definitely room to improve on the tune amd power to be had. Plus you get top notch support with A&C. If you'd like just pm me your number and i'll give you a call. There is other benefits to the tune aside from only power numbers. Cooler rumning temps, skip shift removal, just to name a few.

Todd

 

[alwayscode390]

PM sent, thanks Todd ---

 

[alwayscode390]

Just uploaded my A&C tune ... here is a BEFORE and AFTER vid of the addition of 1.7 RR's and Tune :

BEFORE:

http://www.youtube.com/watch?v=W3SK4iWyrgA

AFTER:

http://www.youtube.com/watch?v=IlMnUHdAtDA