Frankenstein Motor

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Junior Member
here we go.... im looking into building a frankenstein motor using the bottom end of a b20z motor from a 99-2001 crv (its got a higher compression ratio than the b20b block that comes in the 98 crv's and i dont plan on running a turbo) and using a grs trany. the delema that i have is that i dont know which head or throttle body to run, keeping in mind that i dont want to spend a small fortune on it . i was thinking of using the gsr heads (b18c1) and throttle body OR a type r (b18c5) head and throttle body OR a combination... will any of these combinations work well??? i also plan to add cams later and a few other bolt ons and hope to be running closer to or above 250hp if possible. also, i was in lordco the other day and i saw that Edelbrock cam out with a throttle body made for the type r... treasure or trash??
my main concern is the valve to piston clearance.... ive read that it can be pretty close and not recommended.

What's your budget? A properly built B20/VTEC engine usually does cost a small fortune. It's not a cheaper way to get more power- it's a combination to make more power than other NA B block setups. If you're wanting to make significantly more power than the ITR engine, be prepared to spend way more than the cost of the ITR engine swap itself.

If you want 250hp, it really doesn't matter which B20 block you use, since you'll be replacing the pistons no matter what. The pistons are really the only difference between the B20B and the B20Z short blocks anyway. Get the cheaper one, or the one that's in better shape.
well this is the plan... im lookin at buying a high km 96 civic hb for cheap and also buying a writen off gsr or type r (if i can get it at a good price) and then doing out the civic. my bros friend just did the same deal with a type r into a 94 hb, gutted the inside, ect.... its like a go kart on roids and im no stranger to fast cars.

ill have about $15K CAN to play with for a finished product. i was reading up on the b20b's and b20z motors and in the end of most articles, the guys were saying that you should go with a b20z if your not planing on boosting it.... its just cause the 20z has got a compression of 10.4:1 or something and the 20b has got 8.?:1. realistically, i would not want to spend more than $3000 TOPS on the motor (not inc for new exhust, header, intake).

why would i have to replace the pisions?? and whats 'ITR?

im also not really apposed to boosting any b20 motor (with gsr or type r heads) but i think that may cost more than i want to spend....
also another thing i want to know is what ECU would i use?

did you mean $15K in canadian? how much is that in american dollars? with that much money, you should be able to build the b20, no problem. I did the same thing that you did, i bought a 97 h/b really cheap and now i'm building the motor as we speak (ls/vtec btw, i didn't have enough money to buy b20 at the time, hehe) anyway, about the ecu, i believe the p28's are good because you can reprogram it??? not sure about that, please correct me if i'm wrong. keep us informed as i will keep everybody informed about my shit as soon as i'm finished with my project. waiting for tax return, muahhaha, peace!
its roughly like $10000 US that i have eventually to burn to have my daily driver.... but i only want to spend like $2000 US area on the motor. i want to be running low 13's if not in the 12's if i can. we'll see....

"calesta", why would you think that i would need to replace the pistons??
OR cause i want to buy a writen off integra gsr (or even a type r but i doubt i will find one) to switch all the better parts to the civic, should i think about turbo-ing that motor?? (would definatly save me some money from not having to buy a b20 motor and doing that out) .....hhhhhhhmmmmm. what type of work would i have to do to safely run like 10-10 psi or 250 hp (rods, pistons. cams, ???) ?? i know that i would need to get the header modified to fit the turbo setup and most of the other parts. whats the best 'bang for your buck' turbo kit or mitsubishi turbo that i should find? still keeping in mind that i dont want to go too crazy.

I think you need to replace the pistons because there's no way you're getting 250hp from a B20 with ANY head all motor unless you raise the compression. If you're going to boost or use nitrous to get there, then that's a totally different story.
no no...i would fix/mod out the gsr motor when i buy a writen off gsr (i would buy the whole car). i would use the brakes, trany, seats, lsd, and anything else i could use in a 96 civic hb (6th gen) to make a fast car. im now asking if i (a) go the b20 route with a gsr head or (B) turbo-ing a gsr motor??? and in turbo-ing the gsr motor, what kind of mods AND prices am i looking at.... ???
2 grand will not get you a cr/vtec.
2 grand will not get you a b16a2

you need a much larger budget to even consider that
I got quoted for 1000 bucks for a b16 head and to mate it to a b20 block from a good shop in Tulsa, OK awhile back. So, there is a rough estimate of what you might have to pay.
I see B16 and GSR heads on the net for around $450-$800 bucks.Look around and you'll find parts well within your budget.There are a lot of people who start projects and don't finish them and sell off the parts,or who are sick of their set up and just want to get something new.
Originally posted by Domeskilla@Feb 13 2003, 03:49 AM
I got quoted for 1000 bucks for a b16 head and to mate it to a b20 block from a good shop in Tulsa, OK awhile back. So, there is a rough estimate of what you might have to pay.

I think I know which shop you're talking about... I've heard of some pretty cheap prices up there in Oklahoma for VTEC conversions. I just wonder how good of a job they do.

Oh wait nevermind- the shop was in Lawton. They quoted a guy $3500 installed for a B20/VTEC with no internal mods.
Damn, this 1000 was from Xtreme in Tulsa, OK. I wouldnt trust anyone in Oklahoma, simply b/c this state isn't known for anyone with that much knowledge and if they do, i'd like to be proven wrong. As i have been convinced, all my shit will goto Intercrew for a lot of things and probably here for the pnp job. Now sure quite yet. :D
If you wanna get the B20Z then you will have to take out the pistons and enlarge the valve relieves to work with the VTEC valves.....B20B with PR3 head compression will come out to 9.095499790225623:1 with OEM Gasket.
B20Z with PR3 is little less then 9.960276408930555:1 with enlarged valve relieves...
..i just saw the part where you wanna make around/above 250hp..if your talkin about wheel-horsepower then Goodluck..! if you really wanna make that much power..OEM pistons shouldnt even be in your head! :wacko: