MAGNA Meet April 2022 in Delaware

PRyan

Member
Joined
Feb 24, 2020
Hi Guys,

Does anyone know where I could buy one of the Bosch 237 Fuel Pressure Regulators that came on the 89 Turbo Trans Am? I have been doing some reading and have read a few posts that said for a close to stock car that the 237 regulator would work for me to install a Turbo Tweak chip and increase my fuel pressure. I am trying to keep my car as close to stock appearing as possible for smog reasons here in California and am trying to avoid an adjustable regulator. I did find a replacement regulator for the 89 TA on Napa's website, but it wasn't Bosch and I wasn't sure about the quality of the part. Google searches for a Bosch 237 hasn't located anything so I am thinking that maybe Bosch doesn't make these anymore?
 
I have a nice used one I’ll sell. $50 PayPal, shipped if your interested.
 
GM (ACDELCO) stopped packaging the Bosch 237 fpr in January 2012. Bosch actually continued to manufacture these for a few more years, ending production of the 237 fpr in 2015. they were available in both bosch and acdelco packaging as well as privately labeled packaging from some of the aftermarket part retailers.

Being in CA presents a whole bunch of issues with the state's inspection processes - both the visual and the smog portion. Perhaps some of the CA folks can chime in to verify if the CA visual inspection will notice that a "237" marked fpr was not original on a turbo regal whereas the inspector is looking for a "233" marked fpr. I bring this up as the later produced fpr's had the BOSCH wording and part # printed on a label that is easily removed with the soft heat of a hair dryer. attached pic shows the comparison to the printed part info vs the label. CA is a struggle from what others have shared noting their trials and tribulations with the inspection process.

I have new 237 fpr's, with either the printed wording or the adhesive label version. But I can't offer one for what Thumper noted above. There are a couple of vendors who have new 237's as well but those vendors have these 237 fpr's priced at nearly 4X what Thumper is asking.

Check with other folks in CA or call turboLou to determine if the visual inspection will flag a "237" marked fpr in place of a "233" marked fpr. Comfirm with Thumper what he has and go from there. If I can help, let me know.
 

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I have a 233 adjustable that worked fine when i upgraded to a billet one pm me if you need more pics...I can text or email them
 

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GM (ACDELCO) stopped packaging the Bosch 237 fpr in January 2012. Bosch actually continued to manufacture these for a few more years, ending production of the 237 fpr in 2015. they were available in both bosch and acdelco packaging as well as privately labeled packaging from some of the aftermarket part retailers.

Being in CA presents a whole bunch of issues with the state's inspection processes - both the visual and the smog portion. Perhaps some of the CA folks can chime in to verify if the CA visual inspection will notice that a "237" marked fpr was not original on a turbo regal whereas the inspector is looking for a "233" marked fpr. I bring this up as the later produced fpr's had the BOSCH wording and part # printed on a label that is easily removed with the soft heat of a hair dryer. attached pic shows the comparison to the printed part info vs the label. CA is a struggle from what others have shared noting their trials and tribulations with the inspection process.

I have new 237 fpr's, with either the printed wording or the adhesive label version. But I can't offer one for what Thumper noted above. There are a couple of vendors who have new 237's as well but those vendors have these 237 fpr's priced at nearly 4X what Thumper is asking.

Check with other folks in CA or call turboLou to determine if the visual inspection will flag a "237" marked fpr in place of a "233" marked fpr. Comfirm with Thumper what he has and go from there. If I can help, let me know.

Anthony P, thanks for all of the good info. I figured Bosch had stopped making the 237 since I had not had any luck locating a brand new one. My experience with smogs here in CA is that unless you have an aftermarket part on your car that does not look like stock then most smog shops won't bother you too much. In the past when I have had aftermarket parts on my car that did not look anything like stock, the smog tech will check for the appropriate smog legal part number. I usually ask for a pre-test on my older cars just to ensure that they pass the tailpipe test and see if the shop will have any issues with the visual inspection and so far I have good luck with that approach over the years.

I am trying to keep the car close to stock though to try and not cause myself too many smog related issues. As a newer GN owner, I have read that one of the best upgrades even for a near stock car is to remove the factory chip and replace it with a TurboTweak, but it seems that the TurboTweak chip requires an increase in fuel pressure over the stock 233 regulator. I'm guessing the TurboTweak chip probably won't work too well without the increase in fuel pressure, so maybe I will reach out to Eric at TurboTweak and pose the question. When I had emailed him previously he did recommend that I run his emissions chip at smog time. Others have mentioned TurboLou as one of the best tuners here in CA. Unfortunately I am not near him, but it may be best for me to hold off any upgrades and see if I can get my car down to Southern CA to him in the future and let him work his magic on some basic upgrades that wouldn't take me too far from stock while keeping me smog legal.
 
I have a 233 adjustable that worked fine when i upgraded to a billet one pm me if you need more pics...I can text or email them
Thanks Speed Demon, I appreciate the offer and will reach out if I decide to move forward with buying a TurboTweak chip. Kind of re-thinking things at the moment...damn CA and its smog test!
 
just use a c-clamp and a socket to squish the 233 until you get the base pressure you're after
 
Hi Guys,

I bought the used 237 regulator from Thumper. The regulator arrived and looks like it is almost brand new, thanks Thumper!
 
Glad you got one. Thumper is one of the good guys here.

You'll need to confirm your fuel pump. OE fuel pump output was about 51 psig - enough for the 34-37 psig static fuel pressure (vac line off) with the Bosch 233 and the stock 14 # boost. Now with a TT chip and the 237 fpr, you'll need to update the pump to supply static fuel pressure plus boost #.

static fuel pressure with 237 => 44 psig. 44 + 16 (or 18 # boost) => 60 - 62 psi. so you'll want one of the 255 liter/hr fuel pumps as an update. you'll need a fuel pump hot wire kit as well. new fuel pump will draw more current than stock + factory wiring is thinner gauge resulting in voltage drop (even more of a drop from 12VDC when headlights, etc are on), further drawing on the charging system. the hot wire kit solves the factory wiring limitation.

As you noted, get the emissions chip with the street chip from Eric. You should have some sort of scan tool to help you confirm sensors and operational data from the engine. whether you choose a dedicated ScanMaster device for the Buick only or a scan tool like the Bosch-Actron CP9690 that can be used on any of your vehicles is your choice.

here is link to Bosch unit at Jegs: Bosch-Actron CP9690: Elite AutoScanner Code Scanner Kit OBD-I, OBD-II and CAN | JEGS

You're well on your way to further enjoying your turbo Regal. These changes are pretty straight forward - don't know that you need someone like turboLou to do them for you. Thumper is a good guy to talk with and you are probably up to speed with all of this by now. Enjoy.
 
Glad you got one. Thumper is one of the good guys here.

You'll need to confirm your fuel pump. OE fuel pump output was about 51 psig - enough for the 34-37 psig static fuel pressure (vac line off) with the Bosch 233 and the stock 14 # boost. Now with a TT chip and the 237 fpr, you'll need to update the pump to supply static fuel pressure plus boost #.

static fuel pressure with 237 => 44 psig. 44 + 16 (or 18 # boost) => 60 - 62 psi. so you'll want one of the 255 liter/hr fuel pumps as an update. you'll need a fuel pump hot wire kit as well. new fuel pump will draw more current than stock + factory wiring is thinner gauge resulting in voltage drop (even more of a drop from 12VDC when headlights, etc are on), further drawing on the charging system. the hot wire kit solves the factory wiring limitation.

As you noted, get the emissions chip with the street chip from Eric. You should have some sort of scan tool to help you confirm sensors and operational data from the engine. whether you choose a dedicated ScanMaster device for the Buick only or a scan tool like the Bosch-Actron CP9690 that can be used on any of your vehicles is your choice.

here is link to Bosch unit at Jegs: Bosch-Actron CP9690: Elite AutoScanner Code Scanner Kit OBD-I, OBD-II and CAN | JEGS

You're well on your way to further enjoying your turbo Regal. These changes are pretty straight forward - don't know that you need someone like turboLou to do them for you. Thumper is a good guy to talk with and you are probably up to speed with all of this by now. Enjoy.
Hi Anthony P, I haven't confirmed which fuel pump I have yet, but looking thru the paperwork given to me by the previous owner it looks like he installed a Spectra fuel sender. The Spectra fuel sender mentions that it should not be used with a hot wire kit (not sure if this is just to protect Spectra or if the unit would actually catch on fire) so I was thinking about replacing both my sender and pump when I am ready to. I was going to start another post to get some suggestions for the replacement parts, but I have found a Racetronix unit on GN1's website (Link to part) for $269 that looks like it would probably meet my needs. I am definitely open to other suggestions as well so if anyone has suggestions other than the Racetronix part, please let me know. I was considering Eric's TurboTweak pump until I found the paperwork on the Spectra sender.

For my scan tool, I just installed a ScanMaster G about a month ago as part of my spring cleaning, then I adjusted my TPS and IAC. I still need to clean my intercooler, replace my transmission fluid and filter, and my fuel filter when I replace the Fuel pump and sender, but I am making progress slowly but surely. I'm more of a tinkerer and not as knowledgeable about these cars as many on this site, but I have been doing a ton of reading on the site as well as others so I appreciate you giving me the tips and recommendations about the fueling system upgrade.
4CDA9BB0-7127-4791-AED1-80A3A820F460.jpeg
 
nice job protecting the driver's seat material.

spectra hanger FG156A is fine. the yellow molded block wiring connector is the weak spot on these and Racetronix hangers. However, that scenario comes to light when using larger fuel pumps or double pumper setups on a factory-like hanger. At stock-like performance level, don't know the Racetronix setup linked above is necessary. don't need to overspend and over build.

links below good reading...filter out the snipping between members results in good info to know...

Which Fuel hanger

next thread has pics illustrating the damage at the yellow molded block due to high current from larger fuel pumps (and possibly the lack of a hot wire kit). Spectra's disclaimer about not using a hot wire kit is to protect themselves. by providing a stable voltage to the fuel pump, there is no variance in current, V=I*R. remember, some folks here are all about racing results at the track. sometimes the well-intended advice from someone whose sole focus is racing is lost on someone trying to keep the car stock and factory appearing.

Fuel pump connector melted

besides deciding whether a gerotor fuel pump (Walbro) or a turbine fuel pump (DW & Racetronix (same DW factory)) is what you'd prefer, I will also highly recommend you do not oversize the fuel pump. everything on these cars is a matched system. Installing one oversized component because one day you might utilize its full potential, is a recipe for problems. with a TT street chip at 16-18 psi boost, the engine needs about 62 psi fuel pressure. One # boost equals about 10 horsepower. so, about 20 - 40 brake HP over stock engine making about 290bhp at 13.7 psi boost.

folks have run into problems getting fuel pressure down to the 42-44 psi range when installing larger pumps - DW300 (340lt/hr) vs DW200 or Walbro F20000169 (255 lt/hr) on a basically stock street car. AND when the vac line is re-attached to the fpr, there should be a drop in fuel pressure equal to half the value of the engine's vacuum level at idle. if 18 in-hg at idle, there should be a drop of about 9 psi fuel pressure when the vac line is re-attached to fpr. many are only focused on the fuel pressure setting with vac line off and don't recognize the second part of verifying pressure drop once vac line is reconnected.

Also, the Delphi fuel pump, FE0114, that was used in the GMC Typhoon and Syclone will give you 62 psi fuel pressure and the flow rate needed.

this thread below reviews the fuel pump vs fuel pressure issue:

FP Regulator bad?

if you choose a DW, confirm that is has a check valve installed before purchase. DW was making their pumps recently without a check valve. for a racer who operates the fuel pump via a manual rocker switch, who cares. but on a street car when the operator is looking for the 2 second fuel pump prime action when ignition is rotated to key ON and the fuel pressure immediately drops to zero after those two seconds there will be a thread asking for help troubleshooting. Also, fuel system should hold pressure for about 30 minutes after shutting off engine. no check valve, fuel pressure drops to zero as soon as the engine is off - again, another thread asking for help troubleshooting. DW did begin a free service to install a check valve. there is a thread on that as well.

Lastly, verify your fuel injectors. The OE Bosch pintle injectors don't like to sit in today's ethanol component pump gas. After only going a few hundred miles over a few years, this is how poorly brand new Bosch stock injectors flowed due to sitting. Calibration injector is at LEFT.
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Once ultrasonically cleaned, all six flowed about equal, albeit less than the calibration injector of 29.8 pph @ delta-p of 45 psig.... tolerances....
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the Lucas 30pph disc injectors (5207009) are a fine replacement for a nearly stock engine and can handle up to about 380 bhp. efficiences of stock turbo and factory intercooler max out about 360bhp. disc injectors won't foul like the old style pintle design. best pricing on these is direct from Racetronix...
Racetronix-Delphi_Injector_Sale-42s

these 30pph 009's flow perfectly like the OE Bosch 0 280 150 218 calibration injector on LEFT...
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I had stopped the flow test early as I was told these were 42pph 009's. 42pph are part# 5208009 - also with a green band.

Since you are already getting a street chip and an emissions chip from Eric, he does sell a chip and injector package. while the 42pph injectors can handle low 500 bhp range, Eric can burn a chip correctly for them for proper operation on a nearly stock performance level engine. a chip + injector package saves a little $$ vs buying separately, maybe.

the gnttype.org site is a wealth of info. fuel system tech page and the charts showing relationship of fuel injector, HP, and fuel demand help put things into perspective...

Fuel System

Performance, Horsepower, Injector, Fuel, and Turbo Guide

tech sheets for some of the fuel pumps are attached for reference. lots to review. take your time...and do the work once.
 

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I have a stock 237 regulator which was "squeezed" to increase the fuel pressure by 10 lbs... let me know if interested.

Claude.
 
Thanks Anthony P for the recommendations and for sharing all of that info. I am definitely looking to take my time and buy the right parts. I am also looking to better understand my car and the options in regards to parts prior to moving forward so I will be reading the links you provided. Are there any differences in the gerotor vs. turbine fuel pumps regarding longevity, noise, etc? I don't recall reading anything about pintle vs. disc injectors so I will need to read up on that as well.
 
longevity...a bit too open-ended of a question. any properly sized fuel pump operating under normal conditions will operate for years and years and years. of course there will be one that fails randomly on a daily driver. I had a fuel pump fail on a new car daily driver after almost 3 years and some 40K miles total.

fuel pump noise is a better focus topic. whine or whurl?

most important is to keep or re-install the foam sound deadening sleeve on to the pump shell.

gerotor pumps like the Walbro do whine. On a '99 Suburban, the OE pump (presumed Delphi) was quiet. The Walbro replacement, even after transferring the beverage can-like foam cozie sleeve sound deadener, was stupidly loud. with engine at idle, you could hear the Walbro pump whine from like 10 feet away at the rear of the truck. on a race car, who cares? on a street car, the noise sucks to hear.

on longevity - Walbro did have a manufacturing quality control issue about 10 to 12 years ago. the company that owned Walbro at the time did not handle the pump failure well, sticking responsibility to the distributors who in turn, not wanting to eat the cost of pumps, stuck it to the end user consumer. the need for original receipts and default warranty period of 1 year ( I think) was pushed on to the end user vs Walbro recognizing that a certain date range of pumps was affected. Ultimately a date range recall was enacted and many vendors extended the date range to satisfy customers. I remember reading about many a racer who detonated an engine by low fuel pressure under high boost on a pass down the track - the inherent risks of racing... the Walbro brand has been bought and sold a few times over the past years...

turbine pumps would be quieter than gerotor pumps. turbine pumps have an inherent whurl to them. again the foam or neoprene(?) sleeve should keep the whurl noise down.

Racetronix labeled fuel pumps are just private-labeled DW pumps. at one time they were made in the same factory as the DW pumps. probably still are today.

for your setup as a street car operating on pump gas only (91 octane in CA), at 16-18 (16-17) psi boost by Eric's TT chip, I'd compare the DW200 (255 lt/hr) to the Racetronix equivalent to the Delphi FE0114. to install the DW pump on the factory hanger (spectra replacement included) may require a little tweaking of how it fits in the hanger and then with the fuel sock in the dog dish in the tank. but this DW concern may be fitting the DW300 to the factory hanger - don't remember. the Delphi pump is all you need and fits fine. it's about $50 delivered to your doorstep, if you shop accordingly. Compare that to the cost of the DW200 or Racetronix pump...

if one day you change the performance level from about stock levels, you'll need changes. installing too big of a fuel pump to one day, possibly, grow into it is not a good idea.
 
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