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New motor and turbo build


questtuner82
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Ok so im building a new motor and turbo. Specs of motor... .40 over with je custom pistons 7.5:1 c/r, custom carillo h beam connecting rods, block is race prepped with webbings machined down. Race prepped crank lightened knife edged renitraded with chromed journals chamfered oil holes. Balanced rotating assy bse kit block was zero decked. Amc marnel head with 2" and 1.6" stainless valves maganese bronze valve guides heavily ported and polished chambers are smoothed and polished and cc'd custom grind turbo cam. 304 duration .530 lift 108lsa beehive springs with 110lb seat pressure custom typhoon style intake with velocity stack runners 72lb injectors and 80mm throttle body. Now for the turbo..... Garrett gt35r ball bearing turbo oil and liquid fed ext w/g. Not exactly sure of specs. I believe it is 70a/r. Its going on a custom header with dual 38 mm wastegates. 4" inlet 2.5" outlet cold side with 3" exhaust outlet. Just trying to figure out if this turbo will work good with this build or if its too small or to big. Also using a big intercooler by mishimoto with 2.5" in/out and 2.5" ic piping. Will be using ms3 and edis with cop. Id like to know what ppl are thinking on this setup and how the engine/turbo will perform. Also just curious on hp guessing? This will hopefully be installed in spring as all winter the car will be torn down and full suspension restore and body restore. Any suggestions on turbo would greatly be appreciated. Motor is already built just looking for some turbo info/suggestions for my setup
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TB is a little big. 65mm is 2.5". Having a bigger TB than the IC and turbo outlets doesn't help. It just makes throttle tip in harder to tune. I'm using a 65mm TB from a ford 4.6 on mine.

 

A GT35r can flow 60 lb/min of air. That's enough to get a 4g63 into 600+hp territory. So take that into consideration whether or not the turbo is bigger than your power goal.

 

72lb injectors will get you to around 300-350 HP on pump gas. If that's your power goal then you're set. If not go bigger. I'm running 120 lb injectors.

 

Dual 38mm WGs is a bit overkill. Only really used for split port turbos. My GT35 has a single 38mm external WG.

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Ok thanks for the input. The turbo is a twin scroll housing and the header is twin scroll flanged as well. I plan on running like 30-35 psi boost. So bigger injectors??? Not sure what i plan on putting down for hp yet but would love to get as much as possible. As tim allen on tool time says "more power" lol. As for fuel i have easy access to vp racing fuel which is 112 octane so i think ill be using that in this car. So smaller throttle body?? My intake isnt totally finished so i can still do the smaller t/b if it would help with tune and throttle response
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2.5" pipes feeding a 3.15" valve (80mm TB) means the TB can outflow the IC pipes. That means you will hit full throttle before you hit full throttle. Meaning somewhere around 1/2-3/4 throttle opening and you will be flowing all the IC pipes can feed. Pushing the throttle down farther will yield no extra power. Not to mention it will be harder to take off from a stop light without giving it too much throttle.

 

If you plan on boosting 30+ psi then 72lb injectors are gonna run out of fuel before you get there.

 

 

Have you factored in trans, driveshaft, axles into your HP goal? Stock trans will not hold up to those power levels. Neither will the stock u-joints. And if you plan on drag racing the CV axles probably wont hold up. People have broken the stock trans at around 300hp. At 30+ psi with sticky tires the only reliable parts behind the engine will be diff and wheel hubs. The rest of the stock parts will break.

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Not sure about trans yet but the rearend is going to be a ford 8.8" out of a thunderbird. The cv axles are going to be a custom made set that uses the 89 rear hubs and will work with the ford rear diff. This also allows me to get alot more options for gearing. If you are familiar with the 89-95 thunderbirds they have an independant rear suspension and the rear diff will work with some bracket mods. The driveshaft will end up being custom also.
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Forget EDIS, just go with direct coil control, easy peasy and you get all the ignition retard/cut features of the ECU at your disposal. You can run the EDIS style coil pack, CNP or COP.
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The carillo rods ill have to get exact specs. I do know the crank pin journals were machined down a decent amount and the oil holes were bored bigger then welded again at a different angle to allow more direct oil coverage. There were alot of mods done on the whole build. Ill post specs when i get home from vacation from the blueprints.
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Carillo rod specs are 6.70" center to center wrist pin diameter .987" journal size is 1.997" rod length is 1.175" at rod journal. Note the rods were a custom rod and were $1800 shipped

 

Interesting, just for comparison, stock rods center to center 6.536 with ,864 pin bore (,866 pin dia). crank rod journal dia. 2.086 with rod width of 1.178.

 

Dad

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Yes it is interesting. The pistons are custom made the rods are custom and the crank had alot of machine work done to it. The rod journals were machined down to accept the rods and all the oil holes were enlarged and cut at a different angle then they were welded up and the crank was renitrided and journals were chromed. It was lightened alot and knife edged. Im trying to load pics from photobucket but it wont let me.
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The thicker pin diameter allows more boost psi with less chance of pin breakage or piston cracking. The pin is double thickness for super heavyduty use. They are listed as severe duty pins and is a chevy sbc standard size also the rods are based on the nascar series toyota v8 engines
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Changing rod/ crank angle its used to stroke or destroke a motor a small amount to get better torque or hp depending on build. The head porting and big valves help it breathe. The custom grind cam makes it breathe and the mpi intake is designed to make the motor breathe with high boost applications.
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Dad can u elaborate the reasons why people change connecting rod length and also the benefits of changing rod angle in a engine? For instance on a sbc 383 stroker some people use 5.7" rods and others use 6.0" rods. The longer rods on a 383 create more torque and hp and give you a broader rpm curve of torque/hp gains over a 5.7" rod
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The op motor spec's keep evolving.

 

Ok so im getting ready to get all my new stuff in..... Fully built motor .60 over with je forged pistons pauter rods lightened and knife edged crank bse balanced with lightweight flywheel, ported non jet head with 2mm oversized ferrea stainless valves beehive springs crower custom roller cam with 6g72 roller lifters custom mpi intake a gt35r turbo edis ign 2.5" hardpipe 3" exhaust with apexi muffler. Just wondering what kind of intercooler i should use and can fit in there with little to no mods size or a link would be great

Motor is already done. It was built by early performance. The motor was already .40 over prior to this. The cylinders had some deep scoring so thats why its .60 over. And with the pistons i have in it and with the work done to the combustion chamber in the head ill have 8.5:1 compression ratio. The head is ported and polished to the max and has the biggest valves possible with oversized stems and bigger valve guides that were knurled. Motor should really build alot of power and flow with the head mods. The mpi intake that was built is a replica of a typhoon intake. And has velocity stacks on the runners with a 80mm throttle body. For injectors i have 680cc fast injectors but may have to go bigger or smaller but not sure yet and all the hardpipes are 2.5" all custom made a gt35r turbo .82a/r with 44 mm external wastegate. Im looking at building 30+ psi of boost on this motor

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