View Full Version : Let's Talk G54B Mods
hutch
07-04-2017, 04:26 PM
Hello all again.
If things go well in California will extend it's smog exemption including 1980 vehicles.
Let's start with silent shaft delete? Is it worth it? I'm not only talking monetary. I'm more concerned with performance. How much of the smoothness would I lose?
I will be doing a complete overhaul when the time comes. Higher comp. pistons. Cam regrind. Jet valve delete head. Headers.
Maybe lightened rods. A complete balance of all the rotating parts.
I'm looking to get around 150 hp. Is that doable?
Let's discuss.
Thanks.
ragragtimetime
07-04-2017, 06:29 PM
I believe 150hp should be easily achievable with those modifications you listed. My daughters 1983 4wd has the 2.6L with Doug Thorley tri-y header, no catalytic, John Baker cam, Jet valve delete, & Mikuni 44mm PHH Type S5. I don't know what the hp output is...but if rolling at 5mph & floored the tires will consistently (& easily) spin on dry pavement. The transplant recently took place & yes I will update/post pics.
hutch
07-04-2017, 07:02 PM
Can you even get the John Baker cam?
geezer101
07-04-2017, 09:41 PM
If you're doing a shaft delete, you're getting a set of digital scales and matching all the rod & piston assemblies and balancing the crank. There's a lot of talk about how detrimental is it to remove the balance shafts from an engine but there are plenty of engines around that don't have balance shafts in them and they don't massage your legs from vibration or fly apart. You'll need an M8 head for improved flow (or similar), derestriction of the intake side of the head, a good flowing exhaust system and headers, lightened flywheel, custom ground cam and anything other than the stock inlet manifold (it is GARBAGE for performance). I think an EDIS ignition system is a worthwhile upgrade. If you have the coin for DCOE Webers or Mikuni PHH side drafts, you have the coin to buy bike carbs and get a manifold made up (you'll get change in your pocket and the bike carbs run rings around DCOE's and PHH's for fuel economy and response)
I'd weigh the cost of all those mods vs a used starion motor transplant. Can't match boosted performance
Pushes u back in the seat, while doing it quietly(as u like), plus geting decent mileage.
Folks still parting out starquests or doing LS, JZ, swaps etc
Balance shafts can wipe out a motor, but I'd never delete 'em IF the shafts & bearings look good
2nd order harmonics buzziness is annoying (to me at least)
pennyman1
07-05-2017, 03:02 AM
The combo that Ragragtimetime has in his daughter's truck is good for 160 Hp according to the John Baker catalog. The cams have not been available for years, and were Mikuni "muscle cams" developed with John Baker for his racing these trucks in the 80's at Baja. I have one of the early cams in a head unused that will be going on Geronimo shortly that I would love to profile before use to not lose the cam specs. I am worried about shipping across the country to a cam grinder for fear it will be lost or damaged. The trick to these motors is cam duration, as the cam lift is limited due to the head and valvetrain design. If I can find someone local to profile the cam I will have it done.
ragragtimetime
07-05-2017, 03:24 AM
http://www.mightyram50.net/vbulletin/attachment.php?attachmentid=9191&d=1397262738 (http://www.mightyram50.net/vbulletin/album.php?albumid=306&attachmentid=12984)
here are some performance numbers that may influence the direction of your build
geezer101
07-05-2017, 04:52 AM
Look at the prices and note that this is a really old advert. A performance head for $950 was steep. Work out what oversized valves, full ported head and decked face would cost you now - machine shop labour would be huge). The tricks to getting the 4G54 to breathe are more readily accessible and there are more options (different model heads, using V6 rockers for more lift, DIY porting etc). Going turbo makes numbers easily and using a Starion for a donor would save time and cash but there are pitfalls to going to ECU engine management and the cost of turbo maintenance. I would still prefer an old school NA build for simplicity and day to day reliability. Similar thread -
http://www.mightyram50.net/vbulletin/showthread.php/5935-Upgrading-a-2-6L-to-CFI
hutch
07-05-2017, 07:47 AM
Ok. I'm going to keep the balance shafts. Will the later heads fit the 80's block? I found a valve cover. I can find the head but I can't find the intake manifold. I would like to get a new head with jet valve delete. Does anyone have a intake manifold 1983 plus or so?
ragragtimetime
07-05-2017, 12:43 PM
I just removed an intake from a 1983 2.6L (with working original carb still bolted to it).
hutch
07-05-2017, 02:58 PM
I just removed an intake from a 1983 2.6L (with working original carb still bolted to it).
Any chance you want to sell the manifold? I really don't need the carb but maybe you can give me a price shipped?
Thank you.
The cams have not been available for years, and were Mikuni "muscle cams" developed with John Baker for his racing these trucks in the 80's at Baja. I have one of the early cams in a head unused that will be going on Geronimo shortly that I would love to profile before use to not lose the cam specs. I am worried about shipping across the country to a cam grinder for fear it will be lost or damaged. The trick to these motors is cam duration, as the cam lift is limited due to the head and valvetrain design. If I can find someone local to profile the cam I will have it done.
Cam quality definitely make or break a performance build;
DSMs had weak results with crower and web cams, trying to find a less expensive HKS equal. Deltacam.com delivered
One starquestor haggled with schnieder over his measured specs. Finally got schnieder to agree to remedy. 100hp gain!
My 1st import experience was dismal with crower & another. Advised to get an Iskenderian. Stunned by the performance
Going turbo makes numbers easily and using a Starion for a donor would save time and cash but there are pitfalls to going to ECU engine management and the cost of turbo maintenance. I would still prefer an old school NA build for simplicity and day to day reliability.
NA maybe cool for the goal, but be aware of the downsides. Carbs need constant fiddling. My 32/36 weber hardly tho
My mikuni dual sidedrafts drank fuel and had the most horrible sounding induction noise. I tried the whole jet kit too
At the track I learned why ALL the 'vets' ran webers. Lots more tuning bits, and money$$$$ to get it dialed in also
Not trying to convince, but to mention a few things. Starions require no more maintenance. ECU/wiring pretty simple
While OEM electronics r old they've proven very reliable, there r low buck options for whatever need replacing
Performance worth it? Lots of boosted truck and Raider swaps passed thru starquestclub.... like a natural
BradMph
07-06-2017, 02:45 PM
Love my schneider racing cam. They work with you as well and will regrind free if you decide it wasn't what you wanted. If your cam searching, give them a try and their cam springs are amazing as well.
hutch
07-06-2017, 04:18 PM
I have a brand new Weber sitting on the shelf. I am debating whether to put it on. Honestly my stock carb. works perfectly.
As far as cams? I just want a street cam with a little extra power. Don't want to lose the smooth idle.
hutch
07-06-2017, 05:49 PM
Oh, headers. Anything off of ebay ok? Any certain ones you guys would recommend?
hutch
07-06-2017, 06:14 PM
Oh, headers. Anything off of ebay ok? Any certain ones you guys would recommend?
pennyman1
07-07-2017, 02:45 PM
The Pacesetter header is ok but not great, and is a high rpm power header due to the design. The DG header sold on here is an improved version of the Doug Thorley header that is designed to work with the torque peak of the original cam in the midrange. I have a Doug Thorley header that is going on Geronimo when I swap the head out for the one I have with the Mikuni muscle cam from John Baker and a 38 DGES Weber carb. Oregon Cam grinders are another source of custom cams - they will grind you a cam to match your modifications.
hutch
07-07-2017, 03:21 PM
The Pacesetter header is ok but not great, and is a high rpm power header due to the design. The DG header sold on here is an improved version of the Doug Thorley header that is designed to work with the torque peak of the original cam in the midrange. I have a Doug Thorley header that is going on Geronimo when I swap the head out for the one I have with the Mikuni muscle cam from John Baker and a 38 DGES Weber carb. Oregon Cam grinders are another source of custom cams - they will grind you a cam to match your modifications.
Where here?
pennyman1
07-07-2017, 03:30 PM
http://www.mightyram50.net/vbulletin/showthread.php/1702-DGheaders-amp-custom-exhaust-New-even-port-design-tri-y
hutch
07-07-2017, 10:27 PM
http://www.mightyram50.net/vbulletin/showthread.php/1702-DGheaders-amp-custom-exhaust-New-even-port-design-tri-y
Thanks. What do you think of the quality?
pennyman1
07-08-2017, 02:47 PM
The DG headers are better than the Thorley headers they are based on. They should outlast the truck.
twocarbs
10-31-2017, 12:50 PM
Hi pennyman can you tell me the duration of a good cam and did you get the John Baker profile specs. thanks twocarbs.
ILLA NOIZ
02-14-2018, 10:23 AM
Love my schneider racing cam. They work with you as well and will regrind free if you decide it wasn't what you wanted. If your cam searching, give them a try and their cam springs are amazing as well.
What cam profile did you go with? I'm looking to order one myself.
Doug Thorley Tri-Y Headers and Weber 38
Thanks
geezer101
02-14-2018, 12:27 PM
The 38/38 might be a bit big for the 2.6. You'll likely lose low down torque and throttle response. Probably better suited for a 3.0-4.0 straight 6. If you're planning on putting it on the track and revving it hard it will be o.k.
MattHammer
02-14-2018, 01:56 PM
v-6 rockers for more lift? any specific year of rocker better than any other in terms of amount of lift/design change?
pennyman1
02-14-2018, 06:29 PM
Couple of things about the 3.0 rockers: first, you must have hydraulic lifters to use them. Second, they are a 1.6 ratio to the original 1.5 ratio, so you get better performance from the same cam due to higher lift. Third, I would install new valve springs with the rockers and new lifter - old springs could break from increased compression of the springs, and new lifters so they don't collapse with the new rockers. They also are roller tip on the cam side for less friction - this is a common mod for the starquest groups.
geezer101
02-14-2018, 10:33 PM
Whenever I see performance mods write-ups for the 2.6, duration is the key to improved power. It's generally accepted that lift doesn't help (and depending on who is writing what, extra lift allegedly kills performance) Hydraulic heads are not ideal for performance and are incapable of operating high lift cams or HD valve springs as they rely on oil pressure to operate. Once the load against them exceeds the effort the oil pressure can exert, they no longer are able to generate full lift. Mechanical head, good porting and a wider duration cam and you're on your way to making ponies.
ILLA NOIZ
02-16-2018, 01:35 PM
Can anyone chime in on a recommended cam grind for my 2.6 build?
Doug Thorley Tri-Y Headers, 38 Outlaw and full exhaust planned. Below is what schneider recommended and what I will go with unless anyone else has input based on experience.
From Schneiders: "You want a little grind like our 250-60F"
Yet the grinds listed on their site start at 260-270F
ILLA NOIZ
02-16-2018, 01:37 PM
Sorry...
They recommend 250-260F but the grinds listed on their site start at 260-270F
camoit
02-16-2018, 05:13 PM
We have headers for sale in the for sale section sticky. DG Headers makes them for us. He has the full Doug Thorley try Y and a shorty unit.
As for cams you only have 1 out there you can get and it's a regrind. So it's best to talk to your local machine shop.
ILLA NOIZ
02-17-2018, 06:04 AM
I already have the Doug Thorley Tri-Y and I know cams are all regrinds. The engine is rebuilt but plan to swap the cam out with one from schneiders.
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