Okay, a simple question for the combined experts no this board. I need to know if the injectors I am looking at will fit our TPI and are appropriately sized.

I estimate around ~450-500rwhp with 15psi; which I hope to achieve with a rear mount Turbonetics TC-76. (if anyone wants to give advice on what turbo I should be using I won't mind!)

Thus I am looking at 60lb/hr injectors. I was looking at these siemens deka 60 lb flow matched EV1 injectors on Ebay:

http://www.ebay.com/itm/8-Siemens-Deka-60lb-injectors-Flow-Matched-EV1-Bosch-Mustang-LS1-ANSU-NEW-/281043627534?pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr&hash=item416f816e0e
Any one know if these will work, other posts seem to suggest so but I don't want to get the wrong injectors. I noticed they were 60mm (=2.36")where as our stock ones are 2.7"????


Here are my build specs:


Engine Specs:

357 (350 40 over)
edelbrock performer rpm heads
edelbrock headers
1.6 Roller Rockers
crane cams 2031 lift at cam is 292/302 (=467/482 with 1.6 rockers) with 264/270 duration and 112 lob sep (new part number here: http://www.summitracing.com/parts/crn-104225)

Transmission: PATC build 700R4

3.5" alum drive shaft

Moser M9, alum section with 3.25 gears

3" exhaust


Thanks again!

 

#1 thos einjectors are to short but i think southbay sells adapters to use those, check southbays website, they are also a good place to buy ur injectors from

#2 that cam is really wimpy

 

http://www.summitracing.com/parts/cr...make/chevrolet

get a split ratio set of rockers

 

Thanks, I checked southbay first but only green giants in 42lb were in the tpi section. I cant seem to find any spacers etc for it on there site, I'll try to drop them an email. Any 60lb injectors that are direct fit that you guys know of?

as for #2 well I live in California and smog laws, well, make me go so all I can really say is for the 2031 cam I have: C.A.R.B. E.O. D- 225- 22

Same with the heads and headers and cat's and every thing else on the car... hence rear mount turbo. I can't get to 450 - 500 rwhp with a p1sc and all carb legal components... I can with a remote turbo.

 

Siemens makes 60 lb inj that should fit fine and not be any different than stock. I ran 80's and dont recall them being short? I didnt measure but i believe they came in other heights.
Let me check. Stock injectors really 2.7" long?

Regardless, 42's will do 500 whp in boost. I ran lucas 42's on my hsr system and they were stock sized. I got them from FIC i think, or maybe racetronix? Before i knew of southbay, not sure they were on here in 07-08?

 

Injector size has everything to do with how much air the turbo literally moves at a given psi. There are formula's to determine the size of the injectors that will be needed, but again, it doesn't take into account how much air is being moved by the turbo at a given psi, it only uses a horsepower number and the quantity of injectors being used to help you select. Meaning, your estimate of 450 to 500-RWHP is just an estimate until you visually see the results at 15-psi with that particular turbo, turbo's flow differently. Boost is just a resistance measure, as is an engine dyno, so until you get that thing on the dyno, or start data logging, it isn't as easy as you think to select injectors. Most just do and go with what the next guy did who has a similar build then just dial them in...

 

True hard to say what 15 psi will produce on the given combo. Generally boosted builds run richer than same hp level in a na motor so when doing inj calcs use a higher bsfc number for boosted builds. That will account for the turbo flow and boost pressure to some degree. I have seen 42's make 521 whp n/a and seems to be approaching max cycle duty. Probably would support abit less on boosted motors than need to run richer but not all builds need to be that much richer. You can always up pressure for more flow but around 500-550 whp you start approaching single 255 fuel pump limit.

I see what you are saying tho, a motor that can make 500 hp on 6 psi may beable to get away with smaller injectors than a motor needing 18 psi to make 500, as high boost usually is hotter charge and a slightly richer mix may be needed for the given fuel to prevent detonation. My air fuel is following n/a curves through 6 psi and only then starts to richen up as boost goes up.

450 on boost for a combo like that is easily done with 42's. 500 should be doable as well but 60's would give you room to 650-700

I am just surprised tpi injectors are longer than aftermarkets. All the major brands seem to be 60mm oring to oring height.

 

Sorry there wasn't much info on the injectors. We are in the process of building a brand new website so we really haven't listed anything new in quite some time. We are hoping that it will be up and running within the next month or so. Will keep everyone posted.
Anyway, the Siemens should fit. They have the grooves on top of the injector to accomodate the clips for the rail. The reason that most of the bosch lll's do not fit is #1 they are shorter than the stock, #2 they do not have the grooves for the clips. I see that you found a set of the Siemens on ebay. We have them in stock as well for a couple of dollars more, however we can match the price. If you have any further questions feel free to contact us at any time

 

Thanks for all the input; I understand how difficult it can be to size injectors because of exactly what you are saying. From similar builds etc it seems 60-80lb are what most people are using and based upon injector calculators using I get in the 55-61lb/hr range.

Here is the calculator I was using: used 600 fwhp, 43.5psi and .6/.65 BFSC for the range. ( http://www.rceng.com/technical.aspx )

I want to maintain stock fuel pressure as it is in the sweet spot for the Aeromotive Stealth fuel pump; so as long as idle isn't an issue then slightly bigger is better to maintain lower pressures:

http://realstreetperformance.com/sto...on-test-5.html


If any of you are really bored here is an excel sheet with different assumptions I made to get to the HP on the build with the turbo. There were closer NA engine builds that have dyno charts, but I found a similar enough build with 7psi boost that I thought it would be more reasonable to use that.

 

I bought my Siemens 60lb injectors through Fuel Injector Connection. They sell the 'long' style injectors here.

 

Thanks for your help, because everyone seemed to be uncertain I was hoping for some additional posts from people who know they fit etc. I also really like that you price match; I held off on purchasing the ebay injector because you mentioned this and have such a good reputation on the forum.

I was hoping that some people would be able to tell me if I seem to be in the ball park but given I haven't been flamed its probably a safe bet that 60lb injectors are reasonable. Given this I noticed that others have even used 80lb injectors which would be about spot on for running E85; given the rest of my build is E85 capable I was thinking of running 80lb injectors to allow me to use E85 later if needed or maybe just on the track etc.

In your experience do people have idle problems with that large of an injector if not running E85; it seems I am right where i want to be performance wise but if I fall a little short then switching to E85 will put me where I want to be for sure.

 

Sweet its good to know they fit in your car.

 

i run 65# injectors in my car on gas and they idle just fine , though i belive my megasquirt ecm has more fine control over the injectors then a stock ecm does, but even still i have tons of room for adjustment up or down on the pulsewidth

 

I ran 80's and now 115's with no issues on stock ecm. It is a 400" motor however with fairly large cam. Not sure how they would work in small motors tho, but i have reason to believe it will be fine. The new injectors out there are fast reacting and have good spray patterns, making tuning for small pulsewidths possible.

60's would be fine for you for gas and support decent power on e85. Could try 42's for gas and likely support your power. 60's would be a logical choice for growth. 80's will give more on e85.

 

I ran 80's and now 115's with no issues on stock ecm. It is a 400" motor however with fairly large cam. Not sure how they would work in small motors tho, but i have reason to believe it will be fine. The new injectors out there are fast reacting and have good spray patterns, making tuning for small pulsewidths possible.

60's would be fine for you for gas and support decent power on e85. Could try 42's for gas and likely support your power. 60's would be a logical choice for growth. 80's will give more on e85.

 

Sweet, I will be using EBL P4 Flash... its in the mail! Looks like the 60lb injectors will work as long as I do my part.

 

That is the combo that I am running too, you'll be fine...

 

I know I can run fuel pressure up giving me effectively larger injectors; but I really want to keep a low fuel pressure, base pressure around 40-45 psi, to keep my fuel pump from working to hard or worse yet needing a booster pump. I hear booster pumps are loud to begin with and I am in a drop top so the wine of the motor will drive me crazy.

The more I think about it the more I wan't to be able to run E85; as I said everything else is setup for it. Only draw back is the lack of fueling stations. It doesn't do me any good to run E85 if I can't use it to make more power Based on the 1.47 conversion I really need 90lb injectors if 60s are appropriately sized at 40-45 psi... so 80 lbs at 50 psi will get me to 650 fwhp or so without maxing out the fuel system using e85. All this based upon calculators. I could use a FMU and 42lb injectors but the pressures would be hard on the fuel pump and with the increased linearity and atomization with these injectors it doesn't make sense to me to over work my fuel pump as changing it is a PITA! I'll be using the EBL P4 to avoid an FMU though.

Given that the difference in price between 80s and 60s is very small where as buying a new set of injectors is $400 I am starting to lean toward the 80lb injectors so that I know I can run E85 and increase the boost pressure until I have maxed out the combination. It would just suck to buy 80lb injectors and find out they are to large to tune on pump gas and if I get 60lb injectors is seems likely to limit me to pump gas.

What do you think?

 

I was to busy writing my essay while you were posting; so 60lb are good to go... what do you think about running E85? think i'll max out the 60s? Or should I just stick with 60's and forget corn feeding the IROC?

 

I would just buy 80's, if you are looking towards future upgrades over 550 whp on e85, because a 60 should do 500 on e85 but a single pump probably wont. By the flow numbers the 340 lph stuff should but walbro 255 wont. Just dont know anyone using the 340's as a single yet and actually pushing their limits. If you were gonna go 600+ whp on e85 i would think dual 255's would be required. Not sure a 340 can do that without being pushed hard

 

I wouldn't run E85 just yet until it becomes more and more readily available, unless you have a pump near your home in which case you are very lucky. If you don't, I would just run pump gas with alky injection, as 60-lb injectors would be way more than you would ever need running methanol in the mix.

 

They are phasing out E85 so doubt its goin to be more readily available