Fuel injectors/ boost manifold question
Thread Starter
Drifting
Joined: Aug 2014
Posts: 1,632
Likes: 190
From: North pole
Fuel injectors/ boost manifold question
Im looking to purchase injectors to finish my build! Looking for a good set of matched 80's. I also will be changing my fuel rails down the road not sure which brand? But i want to make sure they will work together. I will be purchasing a boost manifold for my bov,bap,mechanical boost gauge, and alky kit. My question is which boost block to get with correct sizes? Thanks
Melting Slicks
Joined: Nov 2013
Posts: 2,049
Likes: 316
From: USA
Fuel rails take your pick... Holley, racetronix both look pretty nice.
Vacuum block, not sure what size barb fitting those all around, probably 1/8". So for a vacuum block with 1/8 NPT thread that should be perfect.
I'm running Deka 80s and they idle and work great all around. I'm actually kind of looking to upgrade to 1000cc or something around 100 lb/hr. If something comes up, maybe you'd be interested in mine?
Vacuum block, not sure what size barb fitting those all around, probably 1/8". So for a vacuum block with 1/8 NPT thread that should be perfect.
I'm running Deka 80s and they idle and work great all around. I'm actually kind of looking to upgrade to 1000cc or something around 100 lb/hr. If something comes up, maybe you'd be interested in mine?
Melting Slicks
Joined: Nov 2016
Posts: 2,310
Likes: 1,583
From: East Metro (Twin Cities) Minnesota
St. Jude Donor '21
Fuel rails take your pick... Holley, racetronix both look pretty nice.
Vacuum block, not sure what size barb fitting those all around, probably 1/8". So for a vacuum block with 1/8 NPT thread that should be perfect.
I'm running Deka 80s and they idle and work great all around. I'm actually kind of looking to upgrade to 1000cc or something around 100 lb/hr. If something comes up, maybe you'd be interested in mine?
Vacuum block, not sure what size barb fitting those all around, probably 1/8". So for a vacuum block with 1/8 NPT thread that should be perfect.
I'm running Deka 80s and they idle and work great all around. I'm actually kind of looking to upgrade to 1000cc or something around 100 lb/hr. If something comes up, maybe you'd be interested in mine?
From my experience and research (Banish and Dsteck agree) Deka 80s are hard to control and tend to be highly variable at low pulse widths. Kinda like trying to put a nice precise nozzle on a fire hose vs a garden hose. Overall, for the money I would buy the Deka's again but my idle and part throttle trims are doing their job in closed loop keeping the fueling near stoich!! I have no issues at all once you get past the very low pulse widths.
Deka 60'seem to be much more tune-able if they flow enough for you. Not sure why...
Last edited by Toys4Life C5; Jan 5, 2020 at 04:45 PM. Reason: typo
Melting Slicks
Joined: Nov 2013
Posts: 2,049
Likes: 316
From: USA
Yeah I've had no issues or gripes with Deka 80s. I have a mildish 226/230 cam that I've had for a while now.... my car runs better/smoother now with Deka 80 on SD tune than it ever did on much smaller injectors and with a MAF. I did have to tweak the injector data though to get it consistent and really good though.
Melting Slicks
Joined: Nov 2016
Posts: 2,310
Likes: 1,583
From: East Metro (Twin Cities) Minnesota
St. Jude Donor '21
Yeah I've had no issues or gripes with Deka 80s. I have a mildish 226/230 cam that I've had for a while now.... my car runs better/smoother now with Deka 80 on SD tune than it ever did on much smaller injectors and with a MAF. I did have to tweak the injector data though to get it consistent and really good though.
Very interesting, I wish I lived in Florida as I would like to check out your ride. I have had SD in the back of my mind as a potential project but so far my "MAF and then fudge it" tune does everything I ask it to do. What smaller injectors were you running?
Last edited by Toys4Life C5; Jan 5, 2020 at 06:42 PM. Reason: typo
Melting Slicks
Joined: Nov 2013
Posts: 2,049
Likes: 316
From: USA
Generally the Bosch injectors are "better". FIC, and then even a step up further would be ID. IMO the bigger the injectors start to get, the more important quality/good data is since you'll be idling with very small pulsewidths.
Most people seem to have no issues with Deka 80 though...and if they do it's probably something else, or bad injector data.
The best answer to what injectors you should run: ask your tuner. Tuners tend to find what they like best and it's best to stick to what they recommend. You'll have the least issues this way and it's one less variable into the equation, especially if it's an online tune where the tuner isn't physically there and troubleshooting can be tough.
80 lb/hr is equivalent to about 850cc if you're comparison shopping with FIC or ID. But IMO no need to be scared of Deka 80s.
Most people seem to have no issues with Deka 80 though...and if they do it's probably something else, or bad injector data.
The best answer to what injectors you should run: ask your tuner. Tuners tend to find what they like best and it's best to stick to what they recommend. You'll have the least issues this way and it's one less variable into the equation, especially if it's an online tune where the tuner isn't physically there and troubleshooting can be tough.
80 lb/hr is equivalent to about 850cc if you're comparison shopping with FIC or ID. But IMO no need to be scared of Deka 80s.
Melting Slicks
Joined: Nov 2013
Posts: 2,049
Likes: 316
From: USA
I think the biggest reason SD was better than MAF in my case was because of the cam. But the car really does recover from dips better, generally much smoother at low rpm/low load scenario with SD with my cam. That plus the fact I'm flowing over 67 lb/min made SD the obvious choice. Getting a great VE table is definitely a lot more work than dialing in the MAF as I'm sure you're well aware if you've done SD on your Fiero or whatever. I feel like my VE table is about 90 percent solution right now, I'd really like to get on the dyno for a couple hours and run open loop to quickly and efficiently get the last 10% polish done and get those hard to reach cells.
Past injectors I ran when NA.... Lucas 42lb/hr and GTP 36 or 39lb injectors. I originally had the lucas based on tuner recommendations, but then I started my own tuning and tried out the Bosch GTPs..... the GTPs were quite a bit better in low load/idle scenario. I read some stuff about the spray pattern was better suited for LS heads, but who knows. I guess the Deka is a "pencil" spray which also isn't supposed to be as good, but obviously it's working OK, even if not ideal.
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Melting Slicks
Joined: Nov 2016
Posts: 2,310
Likes: 1,583
From: East Metro (Twin Cities) Minnesota
St. Jude Donor '21
Generally the Bosch injectors are "better". FIC, and then even a step up further would be ID. IMO the bigger the injectors start to get, the more important quality/good data is since you'll be idling with very small pulsewidths.
Most people seem to have no issues with Deka 80 though...and if they do it's probably something else, or bad injector data.
The best answer to what injectors you should run: ask your tuner. Tuners tend to find what they like best and it's best to stick to what they recommend. You'll have the least issues this way and it's one less variable into the equation, especially if it's an online tune where the tuner isn't physically there and troubleshooting can be tough.
80 lb/hr is equivalent to about 850cc if you're comparison shopping with FIC or ID. But IMO no need to be scared of Deka 80s.
Most people seem to have no issues with Deka 80 though...and if they do it's probably something else, or bad injector data.
The best answer to what injectors you should run: ask your tuner. Tuners tend to find what they like best and it's best to stick to what they recommend. You'll have the least issues this way and it's one less variable into the equation, especially if it's an online tune where the tuner isn't physically there and troubleshooting can be tough.
80 lb/hr is equivalent to about 850cc if you're comparison shopping with FIC or ID. But IMO no need to be scared of Deka 80s.
This is a very good point - talk to you tuner and see what injectors he has worked with before and trusts the injectors and the data. This could save you a lot of headache and money and make for a happy tuner. Remember Happy tuner, happy life... Oh wait, that was happy wife, happy life.....
Cheers
Melting Slicks
Joined: Nov 2016
Posts: 2,310
Likes: 1,583
From: East Metro (Twin Cities) Minnesota
St. Jude Donor '21
Well, I live in New Mexico now, I'm sure you wouldn't wanna head out this way anyways! I should probably update that.
I think the biggest reason SD was better than MAF in my case was because of the cam. But the car really does recover from dips better, generally much smoother at low rpm/low load scenario with SD with my cam. That plus the fact I'm flowing over 67 lb/min made SD the obvious choice. Getting a great VE table is definitely a lot more work than dialing in the MAF as I'm sure you're well aware if you've done SD on your Fiero or whatever. I feel like my VE table is about 90 percent solution right now, I'd really like to get on the dyno for a couple hours and run open loop to quickly and efficiently get the last 10% polish done and get those hard to reach cells.
Past injectors I ran when NA.... Lucas 42lb/hr and GTP 36 or 39lb injectors. I originally had the lucas based on tuner recommendations, but then I started my own tuning and tried out the Bosch GTPs..... the GTPs were quite a bit better in low load/idle scenario. I read some stuff about the spray pattern was better suited for LS heads, but who knows. I guess the Deka is a "pencil" spray which also isn't supposed to be as good, but obviously it's working OK, even if not ideal.
I think the biggest reason SD was better than MAF in my case was because of the cam. But the car really does recover from dips better, generally much smoother at low rpm/low load scenario with SD with my cam. That plus the fact I'm flowing over 67 lb/min made SD the obvious choice. Getting a great VE table is definitely a lot more work than dialing in the MAF as I'm sure you're well aware if you've done SD on your Fiero or whatever. I feel like my VE table is about 90 percent solution right now, I'd really like to get on the dyno for a couple hours and run open loop to quickly and efficiently get the last 10% polish done and get those hard to reach cells.
Past injectors I ran when NA.... Lucas 42lb/hr and GTP 36 or 39lb injectors. I originally had the lucas based on tuner recommendations, but then I started my own tuning and tried out the Bosch GTPs..... the GTPs were quite a bit better in low load/idle scenario. I read some stuff about the spray pattern was better suited for LS heads, but who knows. I guess the Deka is a "pencil" spray which also isn't supposed to be as good, but obviously it's working OK, even if not ideal.
Last edited by Toys4Life C5; Jan 5, 2020 at 11:12 PM.
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check out fore fuel rails, I like those the best because they are a solid 1 piece design and can be bolted directly to the intake depending what length injectors you get... I used a cheap obx 6 port vacuum block and it works great... you can tee it into your brake booster hose to feed it and get whatever fittings you need for the block to hook up your bov, hobbs switch, etc
Thread Starter
Drifting
Joined: Aug 2014
Posts: 1,632
Likes: 190
From: North pole
check out fore fuel rails, I like those the best because they are a solid 1 piece design and can be bolted directly to the intake depending what length injectors you get... I used a cheap obx 6 port vacuum block and it works great... you can tee it into your brake booster hose to feed it and get whatever fittings you need for the block to hook up your bov, hobbs switch, etc
Last edited by 04zjimc; Jan 7, 2020 at 02:32 AM.
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2020 Corvette of the Year Finalist (performance mods)
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you can run everything you need to off the block, I believe the smaller ports are 1/8npt thread and mine came with a bunch of fittings and plugs but the barb end may not be the size you need so you can just get another 1/8npt fitting with the right barb end that you need and you're good
Thread Starter
Drifting
Joined: Aug 2014
Posts: 1,632
Likes: 190
From: North pole
you can run everything you need to off the block, I believe the smaller ports are 1/8npt thread and mine came with a bunch of fittings and plugs but the barb end may not be the size you need so you can just get another 1/8npt fitting with the right barb end that you need and you're good
Last edited by 04zjimc; Jan 8, 2020 at 11:30 AM.
Acct Suspended APR 2026 by request
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2020 Corvette of the Year Finalist (performance mods)
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https://www.corvetteforum.com/forums...injectors.html ... I used those in the past and they were great... might be a tad big for what you want to do right now but it will leave you some room to grow
Le Mans Master
Joined: Jul 2010
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Im looking to purchase injectors to finish my build! Looking for a good set of matched 80's. I also will be changing my fuel rails down the road not sure which brand? But i want to make sure they will work together. I will be purchasing a boost manifold for my bov,bap,mechanical boost gauge, and alky kit. My question is which boost block to get with correct sizes? Thanks
Last edited by helga203; Jan 11, 2020 at 12:00 PM.
Thread Starter
Drifting
Joined: Aug 2014
Posts: 1,632
Likes: 190
From: North pole
I looked at fic's flow chart 72, 650cc! It seems it would be perfect and would give me room for more power..i will also be running 100% meth i know that will help with the injectors.
Last edited by 04zjimc; Jan 11, 2020 at 01:36 PM.