Ported/Built BC filled head on 171,000 mile shortblock???? Opinions...

[91tizzy]

I have a "race" head that I purchased at an extremely good price...brian crower 280 cams, springs, retainers, and an amazing port job (as well as revised lifters)....head came off a 700hp car that slung a rod and the owner didnt feel like rebuilding it again.

My car has 171,000 miles with about 155 compression across the board on all cylinders..bottom end doesnt sound new by any means and is a little noisy on fresh synthetic oil but I am overly "anal" about noise....still stock head gasket with arp headstuds...my setup consists of 680 injectors/50 trim garret turbo/keydiver setup with all supporting mods but mainly its a stock motor....im running 24 psi and its making decent power....its a very capable high 12 second car (auto tranny with stock stall)....my main concern right now is the car will not respond to anymore boost and I feel the VE of the stock cams is what is holding me back at this point....even at 24psi the difference from 20psi is not THAT noticeable. I feel this head is exactly what it needs....this is still a daily driver.

The question is should I install this head on the original high mileage shortblock in your opinion?

 

[Mr4G]

Stop using the synthetic oil for one!! Your engine has worn itself to be use to the regular oil, if you throw synthetic in it now, it wouldnt be the best idea for it. as for the head, I had just about the same setup except 272 cams and a sleeper 16g on a bottem end that made it to 178k, tore the motor down and everything was clean except for one bearing!! it will handle it but i suggest going with 272 instead of 280s, especially if it s a daily driver!

 

[91tizzy]

I was planning on going with reground delta 272's until the opportunity to grab this head came up....and it is already purchased awaiting install...

I have used synthetic since I purchased the car 3 years ago....

It will hopefully get retired from daily use within the next year and at that point the motor will be coming out to be rebuilt.

 

[bigf4]

id pull the pan off and change the bearing.

 

[BogusSVO]

well if you plan on building the bottom in a year or so... and the head is already be bought.... bolt it on and go....

of just do a quickie inframe build, pop the pistions out and install new rings and rod bearings, and maybe roll a set of mains

but if your compression is good now, I do not see any reason why you would end up issues from a head swap.... unless you get nutty with boost or the way you drive

 

[91tizzy]

Yeah that is the plan anyway...im not tryin to go crazy with boost or anything but I would like to make a safe and legit 400hp out of the car as it sits and run some mid to low twelves....dont think the stock auto will be good for much more than that....I guess the bearings really arent picky on power levels, more on no knock and mileage....

I would do the in frame rebuild if the compression was low but this motor is quite solid for the miles.... I have been very impressed with the car since I have owned it and it has taken the mods it has very well...just tryin to get a judge on if this will be the straw that breaks the camels back so to speak.

anyone with personal experience???

 

[420a-t]

There's no reason to change anything in the bottom end if you have good compression, except mabye looking at the bearings. If you're going to be taking the motor out in a year, isnt worth the work of installing the new head now, or wait a year and do it all at once?

 

[red_devil]

Stop using the synthetic oil for one!! Your engine has worn itself to be use to the regular oil, if you throw synthetic in it now, it wouldnt be the best idea for it. as for the head, I had just about the same setup except 272 cams and a sleeper 16g on a bottem end that made it to 178k, tore the motor down and everything was clean except for one bearing!! it will handle it but i suggest going with 272 instead of 280s, especially if it s a daily driver!

If hes been using synthetic oil then why would it matter? If you have high mileage it does not matter if you use synthetic oil. I have had two cars with 200k using synthetic oil and ran great.

 

[91tizzy]

Old thread but wanted to update now that it has been a while and I have a success story with it....installed the head and car was an insane difference....beautiful lope and with open exhaust it was very intimidating....installed a t3 tdo6h 20g and sprayed the car a 75 wet shot and made a lot of money street racing between me and my buddy....motor stayed in the car because I never had a single issue....ran a 7.81 at 93mph in the 1/8th (with a shitty 2.1 60'---there was a solid 7.50 in it with better launch) with a slightly smaller shot and eventually thought the motor developed a noise in the bottom end at 192,000 miles after it knocked hard on a 150 wet shot driving home from work one day....ended up being the crank sprocket timing gear bolt had backed itself out and was making the noise....car sat for 8 months cause I wanted to make sure the crank wasnt hurt etc....

New spare low mileage stock shorty was swapped in and on the first 1-3 pull at only 21 psi (spring pressure in wastegate) it shears the center diff gear inside the transmission....currently is sitting awaiting new low mileage trans....

Head is still working great and plan on setting the awd auto 20g record in the 1/4 with it once its back together...(the 7.81 8th pass is the fastest I have seen so I believe it set that record already)