Engine/Transmission (1998.5 - 2002) RV275 injector with BOOST?

[DMcLeod]

I get to finally put the injectors in this weekend (wanting mild increase in performance/mileage for towing/camper, etc. ). I know lots of folks put the RV275's in as a stand-alone mod. Does the 24V automatically compensate for the additional fuel by adjusting the boost/air in some way?



Could an addition of a box (Smarty, Edge, etc. ) bleed a little more performance out of the RV275's by fooling boost? I know very little about boxes, and not even sure of what I'm asking. (I likely will not plump down the money for a box for awhile either... just asking). I'm basically just wondering if there's some sort of air/turbo/intake mod to go along with the additional fuel (injector). I love that 21psi boost! Is there a way to tweak that to 25 or??? without hurting something?

Thanks in advance!

BTW, I've got gauges, original style LP, SBC..... otherwise basically stock.

 

[NIsaacs]

When I did my mild upgrade, I did the Edge EZ first then the 275's. The Edge has the built in boost fooler and boost elbow. The 275's will give you a mild increase in power, however without the boost mods the ECM will not allow more than stock boost causing higher EGT's.



The one thing I don't like about the EZ is the advanced timing when the engine is cold. When the engine is cold the ECM advances the timing. This in addition to the EZ is too much and causes excessive engine rattle. I just chug around until the engine warms up then all is well. I did this mod at 36,000 miles and now have 170,000 on it.



On a local dyno, this combo is good for 335 hp and 850 trq. max boost is 32 lbs with 950 max EGT's post turbo. This is usable power as long as the rpm stays above 1800 rpm I can stand on it up hill loaded.



Nick

 

[Regcabguy]

With a stock driveline,an EZ,J-hook and the 275's will produce a great running truck. I didn't notice any increased rattle in my '98. 5 24 v with a similiar combo. EZ's can be obtained inexpensively on these forum classifieds.

 

[Bob4x4]

To run more boost on any of our vp trucks you need to have some type of boost fooling. The Ecm will derate the power when more than OEM is seen.

More boost is not needed when adding just the 275. s

 

[DMcLeod]

Thanks all. Yes, I understand additional boost is not "needed"... . but... .

It just seems like an injector/boost combo mod would be the best, but maybe I shouldn't look at it that way. Maybe they are two individual stand alone mods unrelated to each other?????? I'll get those injectors in and see how I like it first. I'm taking a long trip in a few weeks, so I'm looking for any small increase in mileage. I saw the Edge Mileage Max also, but looks like it doesn't have any boost fooler with it. I don't want any long term detrimental side effects. Interesting comment about the cold engine response to the EZ (especially coming from AZ). I live in AK (extreme cold temps in winter) and hope the 275's have no bad side effects in cold weather operation. I havn't heard of any yet.

 

[NIsaacs]

With a stock driveline,an EZ,J-hook and the 275's will produce a great running truck. I didn't notice any increased rattle in my '98. 5 24 v with a similiar combo. EZ's can be obtained inexpensively on these forum classifieds.

The rattle could be the difference between the SO and the HO. The SO has a compression ratio of 16. 3:1 and the HO is 17:1. Mine is HO as is the OP's. Also the J-hook is for the HY35 turbo used on auto's. The standard transmission uses the HX35 and needs the elbow to restrict boost to the wastegate.



Lol, Arizona is not all desert, it can get cold and snow where I live. I was born and raised in Montana so I know what cold in Alaska means



Nick

 

[bromano676]

i put the rv275 in last summer. I have a 4" banks exhaust, and Brake. BHAF.

I pulled my fifth wheel back through PA after I put the injectors in. great power, no EGT problems, actually got better mileage. the stock injectors bench tested poorly.

There is one hill upstate NY that I have to drop a gear on with the fifth wheel to keep the EGTs in check. Under 1250. I know they say thats fine for a while, but I don't see any reason to push it, I'm not in that much of a hurry.



I just put in a quadzilla boost fooler. I used to run 21 psi. I have not put in the boost elbow yet, I now run 28psi if i get on it.



I was told that the ECM defuels progressively from 16 to 21 psi boost, and that the boost fooler will stop the defuel. something must have changed, the waste gate is the same, but the boost went up.



I can't wait to get the fifth wheel hitched up again.

 

[bromano676]

NIsaacs



are you serious about the 325 set up?

how similar is your setup to mine. I was thinking about the EZ, or the juice but with out the pump tap.



I pulled 218 on the dyno when i first bought the truck, i was hoping 275 to 300 with the mods, after I put the Edge in... .

 

[NIsaacs]

NIsaacs



are you serious about the 325 set up?

how similar is your setup to mine. I was thinking about the EZ, or the juice but with out the pump tap.



I pulled 218 on the dyno when i first bought the truck, i was hoping 275 to 300 with the mods, after I put the Edge in... .

Yes, on 10/04/08 SuperFlow Dyno showed 335 hp and 852. 1 trq. I assume different operators and dyno's get different numbers. Also the time of year and climate would make a difference. I would like to try it again with summer fuel, October where I live would be winter fuel.



I really like the simple EZ, it does as advertised. I keep it on the #3 setting which is rated for 65 hp and 180 extra trq. The 275's claim 30 hp and 90 extra trq. I think the combo makes more power total.



Like I said the only thing I dis-like about the EZ is the cold timing advance. If I was smart enough I might could rig up a switch to shut it off when cold.



Nick

 

[Regcabguy]

Good info. My '98. 5 w/auto used a boost elbow. That was a quick truck with DTT,EZ and Mach 1. 6's. Without the EZ and boost elbow,it was a hot running dog though. I miss the power and the seats in that rig.

 

[DMcLeod]

Wow, did some searching on here last night and found all kinds of info.



Bromano676 - Did you ever throw overboost codes before adding the fooler? Seems like you should have... sort of like running an elbow without a fooler. Seems like your wastegate is set at 28psi for some reason. People who add an elbow without adding a fooler will throw this code. Interesting comment on the stock injectors - I think I'll pop-test mine also.



Regcabguy - Ya, from what I read, the HY35 came in the 2001 & newer autos, so the elbow will work on the older autos. There are other options for the HY35.



NIsaacs - I stand corrected on the Arizona cold. I began life in MT also. You ought to hear this engine rattle at -55F tho!



I'm thinking I'll order up an elbow ($15) and fooler ($60) just to play with on my trip, and then maybe an EZ or Smarty later on. I know it's probably wasted money on the fooler, but that's how you learn, right? Looks like BD and Quadzilla brands are available, possibly others?



Anybody notice a drop in LP pressure (especially @WOT) when changing to RV275's? I'll be paying close attention to that since I'm at about 7psi WOT.

 

[jpickens]

Here's a dyno from ~2002ish... 275hp Rv injectors - Edge EZ

Awesome towing combination.

Truck is an 01 HO 6spd



#ad

 

[DMcLeod]

That is impressive. I'm imagining where the stock curves are in comparison. Is it possible to superimpose the stock curves onto that graph? Sure sounds to me like the 275/EZ combo is a winner (I'm not talking sled pulling here... . just mild performance gains for daily driver/ weekend tower).

 

[jpickens]

Yes it is... that Edge EZ and RV injector combo is quite a kick in the pants. Best part is you can drive it like you drove your stock truck. I had all the gauges at that point and everything stayed happily in check even when towing hard and heavy. Let me add to my last post - that included the boost fooler elbow that comes with the Edge EZ - I installed that on the HX35 etc. I believe I had already deleted the factory muffler but left the resonator in place.

I forget what a 2001 HO stock dyno graph looks like... I 'believe' they peak out somewhere below 220hp and 450ft. lbs. at the rear wheels. (They are 245/505 @ the crank from the factory)

Josh

 

[PC12Driver]

That is impressive. I'm imagining where the stock curves are in comparison. Is it possible to superimpose the stock curves onto that graph? Sure sounds to me like the 275/EZ combo is a winner (I'm not talking sled pulling here... . just mild performance gains for daily driver/ weekend tower).

That graph is a bit misleading. The peak numbers are probably accurate, but the curve is a bit off because of the type of dyno being used. These trucks will spin an acceleration dyno up faster than the turbo can keep up. The result is that there is a bunch more torque in the lower rpms that doesn't show up. That's unfortunate, because that's where this combo really shines. Run that truck on a dyno that can hold the engine back at a set rpm, and you'll see a steeper climb and maybe higher peak torque numbers at a lower rpm. And the best part is that it's all useable power.

 

[NIsaacs]

jpickens, I wish I could scan my graft somehow. It is way different then yours. The hp peaks at 2100 (335) and by 2700 it is down to 200. The torque peaks at 2000 (852) and holds above 800 to 2700 then drops.



Makes me wonder if mine is right



Nick

 

[bromano676]

I set overboost codes once before I put the fooler in. I had trouble with the APPS. I was pulling the fifth wheel through PA last summer. climbing hills on rt 80, i saw the boost go up to 25-28. i am guessing that because the APPS was acting up, the ECM didn't defuel, because it was not seeing the pedal fueling. also the injectors showed bad on that trip. mechanics all said it was because the engine was working so hard.



never happened again. 21 psi consistantly.

 

[DMcLeod]

I put the 275's in today. I like how it sort of pepped up the truck. Seems to idle/run a bit smoother as well. I was empty, but took it up a decent hill on the highway and stomped on it. A little bit of smoke at the lower boost and then the LP went to 5psi (it never went below 7psi at WOT before). I expect I'll get the new DDRP and put it back on the frame. An elbow and fooler are on their way:-laf. A little bit of fun after running it stock for 8yrs now.

 

[bromano676]

i only have the 5 psi low fuel pressure led, and it was installed with the 275's. at first it would blink when i really got on it. then it started to blink more and more. now with the fooler in it blinks around half throttle. i need to change the filter and see if it gets better. I also have an airdog waiting to go in.

 

[ALepley]

DONT CHANCE IT ON THE VP44 5spi is asking for failure. You want atleast 10psi under anyload.