Hydroboost in action videos

[MylilBowTie]

I seen this in my search to edjamakate myself about hydroboost units

http://www.hydroboost.com/multimedia/index.html

I like the 88 442 olds the best

[cliffsta]

thats nuts , oh and i wouldn't mind an Olds. Speaking of Cutlassses, have you seen that Buick Grand National TT that has 1078 HP on the dyno.

[MylilBowTie]

I think so, It smokes the tires up as soon as it spools up. Had twin turbo chargers and the wastegate? came out the fenders? I think

[Grim Reaper]

Why do you need hydro boost?

The only time I can see needing hydrobost in a gas powered vehicle is if your running a ratical cam the provides piss poor vacuum. If you have over sized tires and can't get it to lock then go to a 1 ton master cylinder It will only cost $40 to do it.

All hydrobost does is replace the Vacuum booster with a hydraulic booster. It doe not make any more pressure in the master it just makes the peddle easier to push.

Brake bias has NOTHING to do with hydroboost. That info is misleading on that site. Bias is the CV job and the master cylinder. If you have a bias problem then put an adjustable proportioning valve in the rear circuit.

[Tom]

agreed. The system isen't nessacary, at least not on our trucks.

As for that GN, it was a TT v8

[1FaastC10]

Originally Posted by Grim Reaper

All hydrobost does is replace the Vacuum booster with a hydraulic booster. It doe not make any more pressure in the master it just makes the peddle easier to push.

and when you step on the brakes with the same effort as before, it creates more pressure in the master cylinder, giving you more braking power with the same effort.

[Hydratech]

MyLilBowTie - Glad you enjoyed the vids! Yes - that's my 442 getting pounded

Grim Reaper - I certainly do not wish to wee in your beer, but you might want to reconsider your thinking. The highest average line pressures that can be generated by a vac assist system on its best day cannot hold a candle to the amount of power a hydraulic brake assist unit can produce. Vac assist = 1200-1300 psi vs 1800-2000 psi capability of a hydraulic assist. That is a VERY large difference in available power, most definitely "increasing the pressures in the master cylinder". "Brake bias has nothing to do with hydroboost"? It sure does, why? When you get into potent braking territories, chassis weight shift starts coming into play, to where the weight of the vehicle starts transferring somewhat off the rear and onto the front during hard braking - actually the opposite of a drag strip type launch, where the weight shifts off the front and onto the rears. There is no misleading information on the 'site, and I am willing to back up all of the statements with bonafide facts. Quite the harsh statement you're making there bud, no?!

You state that installation of a larger bore master cylinder will make a vehicle easier to stop? This is simply not true! A larger bore mc will require less stroke to acheive the same volume / brake application, but will ALWAYS require more pedal effort to acheive the same line pressures. Given a pedal pressure of 100 lbs, you will see higher line pressures generated by a 1" bore master cylinder vs the same 100 pounds of pedal force actuating a 1 1/4 bore mc - undisputable simple hydraulic leverages in action here. Not opinions, just fact.

We have a number of very satisfied customers that tried everything to get their trucks to stop well - scads of different master cylinders, all kinds of different vac brake boosters, big brakes at the wheels from larger series trucks, higher coefficient of friction aftermarket brake pads, vac pumps / reserve canisters - all kinds of tricks = still not quite getting the brake performance they desired. After exhausting all known tips and tricks, some were brave enough to try our setups to find what they had been looking for all along. No gimicks, no rocket science, just plain and simply physics. Even the monsters running large by huge axles and brakes couldn't get their 38's or 44's to even think about howling even a little during a max effort stop. Simply toss in a hydraulic brake assist unit with no other changes = now have enough power available to lock up the huge rubber if desired. As far as the system being necessary for your trucks? I agree! For the most part, they stop quite well stock! Once a vehicle gets modified extensively with big cams / tires... things definitely change! Look at the later model one ton trucks from the seventies - somewhat larger brakes at the wheels + _______ What type of brake assist unit? Gm saw the need for a much more potent brake booster to get those whales to stop well. After all the years of piss poor braking complaints on the C/K series trucks, guess what GM has decided to do to cure the issue once and for all? Most all '05 and newer trucks (even 1500 series) will now have hydraulic brake assist units - tell you anything?

One of our satisfied customers sent me this link, I read it and felt compelled to reply. Please do not misinterpret my reply, as I'm not challenging anybody, mean no harm whatsoever, just want to present some facts...

If your brakes work great, there is no need for any upgrades. If you can't stop your beast and everything checks out properly, more available line pressures may be just what the doctor ordered!

Paul -

[Hydratech]

Here's a pic of our system installed - thought you might get a kick out of it

http://mywebpages.comcast.net/maxboo...erinstall2.jpg


Paul -

[Grim Reaper]

Ok Paul

Fact of the matter is apply more pressure to the brakes will make it stop harder BUT the real problem is a lack of braking potential in the first place.


I stand by my statement that "Unless your running a ratical cam this is not needed on a gas truck". I have a 75 with 35 inch tires that the stock master and stock booster with a Disc conversion rear where I modified the CV and installed a Wilwood adj prop valve and can lock the wheels no problem. ALL the Hydrobost does is replace the booster and do the same job. THe difference is it can make more pressure so it makes a softer feeling peddle. It IS NOT NEEDED.

If your having brake problems on a stock sized wheel then you have another problem. Most often that problem is glazed pads and I'll address that in a second.

The BIG problem is the rear drums on these trucks have a TON to do with peddle feel and overall braking power. When the drums are misadjusted, frozen adjusters, over turned drums they have too much peddle travel and the brakes feel like crap. Everytime my brakes feel like crap It's been problems with the drums that a little brake cleaner and adjusting clears right up. Your system is not going to correct that is it? Nope it's a different problem all together so lets not mislead your customers. Till they fix the real problem then they will still have ****ty brakes with a soft peddle. Then the second or third consecutive hard stop they will have really ****ty FADDED brakes.


Another problem Most people short cut the brake jobs and throw pads on without turning the rotors. Hell I'm guilty of that as much as anybody. So now you have a unseated pad on a polished groved rotor. Yep you apply enough pressure to the brakes and you can over come it till the pads glaze.

Most people do not know to chang brake fluid every two years or so. Brakefuild absorbs moisture and the older it is the easier it is to boil it.

The second problem with putting more pressure to the caliper is MORE HEAT. More heat means WARPED ROTORS, BOILED FLUID AND GLAZED PADS. So if you really want to improve your braking the LARGER BRAKES are needed. So your system basicly exchanged a booster that makes it easier to over use the brakes and in the end is going to cause the end user to need to do more brake maintance.

The system has it's place and I really don't have a problem with people putting it on if they want. It does give nice consistant brake feel. BUT for most people its an unneeded expense that the problem they are attempting to correct could easily be corrected by do better maintaince and using quailty parts on their existing brakes.

If they are doing a lot of hills and aggressive driving their money would be better spent on putting larger better designed rotors on that are not going to increase the chance of brake fade from overheating the brakes. Your system will get one or two real hard stops right after each other but its not goign to get 20 or 30 like a bigger rotor and better calipers from Brembo or another company specializing in racing application is going to get. It's impossible because the real problem with the brakes, or the lack of them, hasn't been addressed has it?

For those really interested in this type of conversion. Hit the Junkyard. ALL Deisel trucks in our body comes with this stock and a lot of one tons had it as well. Little shopping and chatting your junkyard down and you could probably get all you need for under $100. Throw a 1 ton master on it and you got way more then your stock half ton system can ever hope to handle.

Balls in your court to dispute those FACTS.

[Grim Reaper]

Ohh yeah.

Maximim baraking doesn not involve locking the brakes. Infact you don't want to lock the brakes. You want o be just before locking brakes to have maximim braking.

[RockHQ]

Grim i feel you're addressing a different problem there, lousy brakes due to worn parts vs. lousy brakes due to insufficient pressure. While i agree that stock vacuum assist brakes are good enough for normal driving, had i the chance to pick between two identical trucks with the only difference being in the brake assist, i would pick the hydroboost any day over conventional.

I've had the opportunity to test drive a LOT of different GM trucks from the 80's all the way up to 2004 models, and i've never found the hydroboost brakes to be "spongy" or too soft. If such problems existed the most common culprit was, exactly like you said, the rear brakes.

I've done some testing on brake fading. For example, once i rebuilt the rear brakes on a G30 van (1998 MY i think) because one rear oil seal had been leaking and the shoes were soaked in gear oil. After rebuilding both brakes i could not get even braking (brake dyno showed 25% difference between left&right, with the side which had not been soaked having lower value). The remedy was to drive around with the parking brake slightly engaged for a few miles. After that the brakes evened out, but did NOT show any fade on the dyno. The drums got hot enough that i could no longer touch the wheel hub caps.

[Grim Reaper]

Originally Posted by RockHQ

Grim i feel you're addressing a different problem there, lousy brakes due to worn parts vs. lousy brakes due to insufficient pressure. While i agree that stock vacuum assist brakes are good enough for normal driving, had i the chance to pick between two identical trucks with the only difference being in the brake assist, i would pick the hydroboost any day over conventional.

Would you pay $600 to have it? Is it that much better?

I am addressing what the claims are on that site and what Paul put me on the spot for. If the only change is the hydroboost being added then other then a softer peddle where is the improvement? It sure isn't bias because it's the master, CV and rear brakes that are going to control that. Till those things are fixed the brakes are still going to have the same issue except a softer peddle.

Tip if you read the web site some of the information is conflicting. In one are it says exactly what I have said and in another area it leads you to believe it will fix problems that are problems with calipers, air in lines and wore out parts.
Example off http://www.hydroboost.com/multimedia/index.html

Here is a 1977 Corvette coupe equipped with a Hydratech booster making a panic stop. Notice that with a stiffer suspension geometry we are able to perform a four-wheel lock and the car stops straight. There is no premature rear lock or strange side effects from the additional braking power

That leads you to believe it has fixed a bias problem.

Paul then posts above.

"Brake bias has nothing to do with hydroboost"? It sure does, why? When you get into potent braking territories, chassis weight shift starts coming into play, to where the weight of the vehicle starts transferring somewhat off the rear and onto the front during hard braking - actually the opposite of a drag strip type launch, where the weight shifts off the front and onto the rears. There is no misleading information on the 'site, and I am willing to back up all of the statements with bonafide facts. Quite the harsh statement you're making there bud, no?!

Yet here they saying the only thing this fixes is booster related problems.

If you are having troubles with your vacuum assist, due to a high duration cam not building enough vacuum or turbo / supercharging, then yes - this kit will really put some very strong and reliable brakes "back into the picture". If you are upgrading from manual braking to one of our conversion systems, you will be pleased with the straightforward, simple to install design, along with a tremendous improvement in braking power. Most "low pedal" and "pulling under hard braking" complaints with performance cars stem from having worn master cylinders, air in the system, ailing flex hoses and calipers, excessive play in the wheel bearings, or worn steering / suspension components. This kit will NOT remedy these types of problems.

and says exactly what I have been saying the paul called me on.

What gives and where what what I posted in the first place at all wrong? It's Identical to what it clearly states that thos problems are in other parts of the braking system according to that quote directly off Pauls site.

[Grim Reaper]

Ohh yeah one more off their site.

The muscle cars you see on these pages all run radical camshafts, and were factory equipped with vacuum powered brake assist units. This presented a substantial problem with overall braking at low engine rpm, due to inadequate vacuum supply to the brake booster.

WASN'T THAT THE VERY FIRST THING I SAID?

[RockHQ]

Grim i would pay $600 if it cured a problem with brakes. Brakes that otherwise were in perfect condition. I guess it has to do with what one has gotten used to, i've always felt more secure with hydroboost brakes but most of the vehicles i've driven had those. However i strongly agree with you that some of the "facts" presented by hydroboost.com are incorrect, brake bias having to do with hydraulic assist being one of them.

Hydroboost definately has many aplications where it can be considered a necessity, and Hydroboost.com most likely has a great product. It just needs to be marketed in a proper way to a proper audience.

[Hydratech]

Grim - I certainly see your points, and even agree with some of them. I want to make sure that you know that I have all the respect in the world for what you are saying!
As far as conflicting informations? Most people want a single answer that covers all aspects, which just isn't possible in most cases. I don't want to sit here and debate about possibly "minced words" or split hairs about the what if's, maybe's and could be's, though I do want to try to clarify some of the issues to the best of my abilities.
First, let's agree that potential mechanical maintenances / repairs required to a brake system are not necessarily the topic here. If the thing is need of repair, then it is just that. IF all components are in tip top shape, and everything that can be done, has been done, to achieve "good brakes", and the vehicle in question is still suffering from less than optimum braking performance = usually means a lack of available line pressures to the brakes at the wheels due to various possible factors. Simply installing 38" plus sized tires will automatically drastically reduce the overall braking capacity, requiring a helluva lot more pedal pressure to properly stop the vehicle, which can be brought back up to snuff quite a bit by installing a much more potent hydraulic brake assist unit. This assist unit will provide the additional line pressures easily, with a much reduced pedal effort required by the driver to safely stop the vehicle. Since you don't have to sit on the brakes as long a distance to stop the vehicle, it actually will only build negligible amounts of increased heat and wear of the brakes - a shorter stopping distance with a higher co-efficient of friction induced by higher applied line pressures will create a very similar amount of heat / rotor temp, as compared to a longer stop with less available friction levels. ??? Yes - the same amount of energy is required to stop the vehicle in both cases, it just occurs at different rates. A quick stop from 45 mph using hydraulic brake assist / higher line pressures will generate suprisingly very similar rotor surface temperatures as compared to a longer stop from the same speed, as the same amount of energy is ultimately required to stop the vehicle from start to finish in both cases, only the span of time during the stop really changes in this scenario.
As far as potential bias concerns? Can you guys envision that if a vehicle performs a super ultra hard stop, that due to some chassis characteristics / dynamics you may find some premature rear lock up possibly occurring due to weight shift OFF the rear tires? What we are trying to illustrate in some of our verbages is that even though the brakes are being actuated in a much stronger fashion, that in most cases the vehicle will remain suprisingly well proportioned. Yes - there are many many caveats in these statements, and there is no "one answer fitz all" scenarios, so yes, there may be some seemingly contradictory or conflicting informations if you really split the hairs of the verbages. There is certainly no direct contradictions desired or meant in any of these informations, just shortcomings in our attempts to convey these informations.
I am curious: Grim, have you ever played with one of these things? I genuinely feel that if you had, maybe you wouldn't be debating the merits of the systems so much? I actually wish that I was in a position to send you one of these setups for you to evaluate, as it just *might* make a believer out of you. I'm certainly not sitting here trying to cram a $600 system down anybodies throats as the best damn thing since sliced bread - I'd be just as happy to hear that you scored one cheap at a local salvage yard and cobbled it into your truck! Heck, we don't even have this platform listed on the website yet. Yes - 6 bills IS expensive! But keep in mind that just a regular ol' stock replacement brand new assist unit from the GM dealer can cost upwards of $800 !!! I'm quite proud of the fact that we can produce a brand new super high quality system as a complete direct bolt in with all the ultra high quality Aeroquip lines, cnc machined billet T6061 firewall mounting... for less than what a stock new replacement would cost! Often finally producing the braking power levels that some customers have spent years and bags of cash trying to remedy to no avail...

Overall, yes - we are working on a completely revamped website with much improved informations, and we will make sure that your comments are carefully evaluated! The largest challenge of doing such is attempting to convey the informations properly, and we will do our best on the next iteration of the 'site to clear up some of the known issues.

Grim - seriously! Try one - I think you'll like it!

[Grim Reaper]

Like I said multiple times. The product has it's place and my original question to the poster is "why".

If he has a lot of cam then YES he needs the product. If he has some other issue then the product may not fix his problem so why should he buy it if it's not fixing the problem he thinks it is going to fix.

My motive was not to down the product it was to make sure this poor guy was buying it for the right reason. If he just wants a softer brake system then great! get it. If he correcting for a blown rat with a lumpy cam then get it. If he's buying it to clean up the appearence under the hood...get it.

I still stand by my statement that all the product does is make it easier to push the peddle. While this may be a benifit to my 90 lb wife I got enough leg that I can damn near break that peddle off and I have infact broken a clutch peddle off my Pontiac.

If he's buying it because he's got brake pull then he's wasting his money. If he's buying it because of a brake bias issue...he's wasting his money. If he's buying it because his bone stock truck empty cant stop...hes wasting his money. Other work needs to be done that will correct those SAFETY issues he has.

As for your offer:


I'll do you one better. YOU GIVE ME ONE and I'LL do a product review on it in exchange. If your product is all you say then your buying advertisement.

You say the word and I'll see if I can get it approved to get it posted on a high profile site that gets 2.5 million hits per month and MANY folks here are also over there.

I'll also let my Airstream buddies know about it because they might want to improve their brakes on their tow rigs and a lot of these folks use vintage tow rigs to go with their vintage campers. www.airstreamforums.com I'm 59toaster there.

I'll see if I can barrow a G meter and do an unbiased test of the product and I'll do it on a BIG HEAVY BIG 454 R20 3/4 ton suburban that just had the front brakes done including turned rotor new carbon Metalics, rears checked and fluid changed. That was less then 4,000 miles ago. PO replaced the Master about 2 years ago. Truck pulls 19HG at idle.

NO ABS. I would never own a GM truck with single channel abs because it's unsafe and a VERY poor deseign. When they can get their heads out of the dark place and put a true multi channel ABS on the trucks then maybe I'll buy a GM truck with ABS.

That will be the real test. Stand on it as hard as I possibly can and see if my truck stops faster with all four tires locked up with vacuum booster or Hydro booster.

Guess what...it will be a tie. You are going to stop the same weight in the same distance on the same surface no mater what system locks the tires because the friction of them sliding tires is going to be the same.

What I want to see to stand up to your claims is I want to see a G-meter show a sustained increase in deceleration. The truck already is capable of locking the wheels so it has full braking potential.

Basicly put your money where your mouth is. I'll give it a fair try and I'll get a buddy that doesn't hang on this site so will not have a jaded oppion to also give his oppion of the performance.

Hes a ASE certified mechanic. Worked Waranty parts testing for SAAB for several years and was a Service manager for a large Chevy Dealership.

I'm an above average shadetree. I do most of my own work including rebuilding my own transmissions both manual and auto.

To show you I'm not full of crap here are other product reviews and tech stuff I have wrote.

http://coloradok5.com/ctm-d44.shtml
http://coloradok5.com/atrondiskbrakes.shtml
http://www.coloradok5.com/milemarkerpt.shtml
http://www.coloradok5.com/stcreview.shtml
http://www.coloradok5.com/packitup.shtml
http://www.coloradok5.com/heatercore.shtml

[NeCrOmAnCeR]

Hydratech -- I have some questions. With the higher line pressures did GM use different flex lines on the front corners and for the rearend? Can the same combination valve be used without modification? I have been interested in these units since early 92 when I saw them on military HUMMERs', and had brake problems with my truck. Also, assuming the system is connected, how much additional P/S fluid is required? And if this fluid has to return to the resevior with the engine off (by emptying the accumulator) will it overflow? Thanks for you time.

[RockHQ]

I see Offroadunlimited.com is offering a hydroboost system too. Only $1200 at that.

[Hydratech]

QUOTE:
Like I said multiple times. The product has it's place and my original question to the poster is "why".

If he has a lot of cam then YES he needs the product. If he has some other issue then the product may not fix his problem so why should he buy it if it's not fixing the problem he thinks it is going to fix. Many reasons - more consistent braking, indifference to altitude, much more responsive pedal, immense space savings, modern components with highly refined operations, greater overall braking power... If there are mechanical problems with the brakes, this of course is not a remedy for required repairs...

My motive was not to down the product it was to make sure this poor guy was buying it for the right reason. If he just wants a softer brake system then great! get it. If he correcting for a blown rat with a lumpy cam then get it. If he's buying it to clean up the appearence under the hood...get it. Agreed - keep in mind that this product is what it is and is not for everybody.

I still stand by my statement that all the product does is make it easier to push the peddle. While this may be a benifit to my 90 lb wife I got enough leg that I can damn near break that peddle off and I have infact broken a clutch peddle off my Pontiac. Got milk or what !?

If he's buying it because he's got brake pull then he's wasting his money. If he's buying it because of a brake bias issue...he's wasting his money. If he's buying it because his bone stock truck empty cant stop...hes wasting his money. Other work needs to be done that will correct those SAFETY issues he has. I couldn't agree more!

As for your offer:


I'll do you one better. YOU GIVE ME ONE and I'LL do a product review on it in exchange. If your product is all you say then your buying advertisement. Funny guy...

You say the word and I'll see if I can get it approved to get it posted on a high profile site that gets 2.5 million hits per month and MANY folks here are also over there. That's a good sized amount of traffic!

I'll also let my Airstream buddies know about it because they might want to improve their brakes on their tow rigs and a lot of these folks use vintage tow rigs to go with their vintage campers. www.airstreamforums.com I'm 59toaster there. Potentially excellent candidates for the swap!

I'll see if I can barrow a G meter and do an unbiased test of the product and I'll do it on a BIG HEAVY BIG 454 R20 3/4 ton suburban that just had the front brakes done including turned rotor new carbon Metalics, rears checked and fluid changed. That was less then 4,000 miles ago. PO replaced the Master about 2 years ago. Truck pulls 19HG at idle. Good candidate - though you must admit that you are already seemingly quite biased in your opinions...

NO ABS. I would never own a GM truck with single channel abs because it's unsafe and a VERY poor deseign. When they can get their heads out of the dark place and put a true multi channel ABS on the trucks then maybe I'll buy a GM truck with ABS. I cannot stand the rear abs system in my wifes '02 Durango! I highly agree with you here...

That will be the real test. Stand on it as hard as I possibly can and see if my truck stops faster with all four tires locked up with vacuum booster or Hydro booster.

Guess what...it will be a tie. You are going to stop the same weight in the same distance on the same surface no mater what system locks the tires because the friction of them sliding tires is going to be the same. Actually, you'd be VERY suprised to find a slightly shorter stopping distance due to the faster response of the hydraulic assist units, in that they can actually respond MUCH faster than a vac booster can to the exact same inputs.

What I want to see to stand up to your claims is I want to see a G-meter show a sustained increase in deceleration. The truck already is capable of locking the wheels so it has full braking potential. Enhanced driver control of the braking events combined with a reasonably skilled driver will allow for riding the thresh hold of lockup at a much more precise level = improved sustained deceleration.

Basicly put your money where your mouth is. I'll give it a fair try and I'll get a buddy that doesn't hang on this site so will not have a jaded oppion to also give his oppion of the performance. I did! We offer a true No BS! Satisfaction guaranteed or your money back in full policy. In the three years that we have been in business, not one single person has yet to return a system!

Hes a ASE certified mechanic. Worked Waranty parts testing for SAAB for several years and was a Service manager for a large Chevy Dealership. I am also an 18 year veteran ASE Master Tech + advanced drivability + undercar specialist = high level of respect for your guy.

I'm an above average shadetree. I do most of my own work including rebuilding my own transmissions both manual and auto. Excellent, though you are not trained in the disciplines of engineering and therefore have a harder time comprehending the concept of what I'm saying to hold true, as all you can gauge with is your life experiences, however extensive they are.

To show you I'm not full of crap here are other product reviews and tech stuff I have wrote.

http://coloradok5.com/ctm-d44.shtml
http://coloradok5.com/atrondiskbrakes.shtml
http://www.coloradok5.com/milemarkerpt.shtml
http://www.coloradok5.com/stcreview.shtml
http://www.coloradok5.com/packitup.shtml
http://www.coloradok5.com/heatercore.shtml

Impressive write ups!

With all due respect, as much as I'd love to make a believer out of you, I will not take you up on your offer, as you have honestly irritated me somewhat with your dialogue / verbages. I must also highly respect the fact that these below links were generated by people that payed full price for their systems:

https://home.comcast.net/~jcmiley/hydroboost.htm
http://www.angryamerica.com/chevelles/hydroboost.html
http://corvetteforum.com/techtips/vi...=190&TopicID=3
http://www.montygwilliams.com/
http://www.hydroboost.com/article/index.html
http://www.hydroboost.com/broncodriverarticle.pdf

If I was to give you a system just because you challenged the concept, then it would disrespect the other hard working people that were classy enough to pony up their hard earned funds for there systems, even if they were initially skeptical.

In a nutshell? Many of your points are obvious, some valid, however you certainly could use some greater tact in your etiquette. Running around talking smack based only upon your strong opinions, possibly only makes you look like a classic "internet keyboard cowboy" - if this is the desired result, then great! However it does come off as somewhat crass.

I must say that I was truly impressed by your tech articles, and they actually showed me that you really truly are a sharp guy! Under different circumstances, I would have proposed that you indeed receive a system for a 30 day evaluation and have you do a tech write up. At this point, I have nothing to prove, and will politely excuse myself from any further involvement in this thread.

NeCrOmAnCeR -
QUOTE:
Hydratech -- I have some questions. With the higher line pressures did GM use different flex lines on the front corners and for the rearend? No - same flex hoses in OE applications, though we recommend you swap them out if in doubt. Can the same combination valve be used without modification? Yes I have been interested in these units since early 92 when I saw them on military HUMMERs', and had brake problems with my truck. Also, assuming the system is connected, how much additional P/S fluid is required? Suprisingly, only about 3/4 of a quart additional fluid is needed! And if this fluid has to return to the resevior with the engine off (by emptying the accumulator) will it overflow? The OE hydroboost spec pumps have a reservoir that is usually only 6 ounces larger and a second return line hose nipple. We have found that the non hydroboost spec pumps are plenty adequate 99.9% of the time, with no overflow problems, even when discharging the stored pressures in the accumulators. Thanks for you time. My pleasure!

RockHQ - isn't that nuts!? $1200? With stock type hoses to boot! Yowza!


Take care guys - over and out...

Paul -